A health system sometimes referred to as health care system or as healthcare system, is the organization of people and resources that deliver health care services to meet the health needs of target populations. There is a wide variety of health systems around the world, with as many histories and organizational structures as there are nations. Implicitly, nations must design and develop health systems in accordance with their needs and resources, although common elements in all health systems are primary healthcare and public health measures. In some countries, health system planning is distributed among market participants. In others, there is a concerted effort among governments, trade unions, religious organizations, or other co-ordinated bodies to deliver planned health care services targeted to the populations they serve. However, health care planning has been described as evolutionary rather than revolutionary; the World Health Organization, the directing and coordinating authority for health within the United Nations system, is promoting a goal of universal health care: to ensure that all people obtain the health services they need without suffering financial hardship when paying for them.
According to WHO, healthcare systems' goals are good health for the citizens, responsiveness to the expectations of the population, fair means of funding operations. Progress towards them depends on how systems carry out four vital functions: provision of health care services, resource generation and stewardship. Other dimensions for the evaluation of health systems include quality, efficiency and equity, they have been described in the United States as "the five C's": Cost, Consistency and Chronic Illness. Continuity of health care is a major goal. Health system has been defined with a reductionist perspective, for example reducing it to healthcare system. In many publications, for example, both expressions are used interchangeably; some authors have developed arguments to expand the concept of health systems, indicating additional dimensions that should be considered: Health systems should not be expressed in terms of their components only, but of their interrelationships. The World Health Organization defines health systems as follows: A health system consists of all organizations and actions whose primary intent is to promote, restore or maintain health.
This includes efforts to influence determinants of health as well as more direct health-improving activities. A health system is therefore more than the pyramid of publicly owned facilities that deliver personal health services, it includes, for example, a mother caring for a sick child at home. It includes inter-sectoral action by health staff, for example, encouraging the ministry of education to promote female education, a well known determinant of better health. Healthcare providers are individuals providing healthcare services. Individuals including health professionals and allied health professions can be self-employed or working as an employee in a hospital, clinic, or other health care institution, whether government operated, private for-profit, or private not-for-profit, they may work outside of direct patient care such as in a government health department or other agency, medical laboratory, or health training institution. Examples of health workers are doctors, midwives, paramedics, medical laboratory technologists, psychologists, chiropractors, community health workers, traditional medicine practitioners, others.
There are five primary methods of funding health systems: general taxation to the state, county or municipality national health insurance voluntary or private health insurance out-of-pocket payments donations to charitiesMost countries' systems feature a mix of all five models. One study based on data from the OECD concluded that all types of health care finance "are compatible with" an efficient health system; the study found no relationship between financing and cost control. The term health insurance is used to describe a form of insurance that pays for medical expenses, it is sometimes used more broadly to include insurance covering disability or long-term nursing or custodial care needs. It may be provided from private insurance companies, it may be purchased by individual consumers. In each case premiums or taxes protect the insured from unexpected health care expenses. By estimating the overall cost of health care expenses, a routine finance structure can be developed, ensuring that money is available to pay for the health care benefits specified in the insurance agreement.
The benefit is administered by a government agency, a non-profit health fund or a
Drug metabolism is the metabolic breakdown of drugs by living organisms through specialized enzymatic systems. More xenobiotic metabolism is the set of metabolic pathways that modify the chemical structure of xenobiotics, which are compounds foreign to an organism's normal biochemistry, such as any drug or poison; these pathways are a form of biotransformation present in all major groups of organisms, are considered to be of ancient origin. These reactions act to detoxify poisonous compounds; the study of drug metabolism is called pharmacokinetics. The metabolism of pharmaceutical drugs is an important aspect of medicine. For example, the rate of metabolism determines the duration and intensity of a drug's pharmacologic action. Drug metabolism affects multidrug resistance in infectious diseases and in chemotherapy for cancer, the actions of some drugs as substrates or inhibitors of enzymes involved in xenobiotic metabolism are a common reason for hazardous drug interactions; these pathways are important in environmental science, with the xenobiotic metabolism of microorganisms determining whether a pollutant will be broken down during bioremediation, or persist in the environment.
The enzymes of xenobiotic metabolism the glutathione S-transferases are important in agriculture, since they may produce resistance to pesticides and herbicides. Drug metabolism is divided into three phases. In phase I, enzymes such as cytochrome P450 oxidases introduce reactive or polar groups into xenobiotics; these modified compounds are conjugated to polar compounds in phase II reactions. These reactions are catalysed by transferase enzymes such as glutathione S-transferases. In phase III, the conjugated xenobiotics may be further processed, before being recognised by efflux transporters and pumped out of cells. Drug metabolism converts lipophilic compounds into hydrophilic products that are more excreted; the exact compounds an organism is exposed to will be unpredictable, may differ over time. The major challenge faced by xenobiotic detoxification systems is that they must be able to remove the almost-limitless number of xenobiotic compounds from the complex mixture of chemicals involved in normal metabolism.
The solution that has evolved to address this problem is an elegant combination of physical barriers and low-specificity enzymatic systems. All organisms use cell membranes as hydrophobic permeability barriers to control access to their internal environment. Polar compounds cannot diffuse across these cell membranes, the uptake of useful molecules is mediated through transport proteins that select substrates from the extracellular mixture; this selective uptake means that most hydrophilic molecules cannot enter cells, since they are not recognised by any specific transporters. In contrast, the diffusion of hydrophobic compounds across these barriers cannot be controlled, organisms, cannot exclude lipid-soluble xenobiotics using membrane barriers. However, the existence of a permeability barrier means that organisms were able to evolve detoxification systems that exploit the hydrophobicity common to membrane-permeable xenobiotics; these systems therefore solve the specificity problem by possessing such broad substrate specificities that they metabolise any non-polar compound.
Useful metabolites are excluded since they are polar, in general contain one or more charged groups. The detoxification of the reactive by-products of normal metabolism cannot be achieved by the systems outlined above, because these species are derived from normal cellular constituents and share their polar characteristics. However, since these compounds are few in number, specific enzymes can remove them. Examples of these specific detoxification systems are the glyoxalase system, which removes the reactive aldehyde methylglyoxal, the various antioxidant systems that eliminate reactive oxygen species; the metabolism of xenobiotics is divided into three phases:- modification and excretion. These reactions act in concert to remove them from cells. In phase I, a variety of enzymes act to introduce polar groups into their substrates. One of the most common modifications is hydroxylation catalysed by the cytochrome P-450-dependent mixed-function oxidase system; these enzyme complexes act to incorporate an atom of oxygen into nonactivated hydrocarbons, which can result in either the introduction of hydroxyl groups or N-, O- and S-dealkylation of substrates.
The reaction mechanism of the P-450 oxidases proceeds through the reduction of cytochrome-bound oxygen and the generation of a highly-reactive oxyferryl species, according to the following scheme: O2 + NADPH + H+ + RH → NADP+ + H2O + ROHPhase I reactions may occur by oxidation, hydrolysis, cyclization and addition of oxygen or removal of hydrogen, carried out by mixed function oxidases in the liver. These oxidative reactions involve a cytochrome P450 monooxygenase, NADPH and oxygen; the classes of pharmaceutical drugs that utilize this method for their metabolism include phenothiazines and steroids. If the metabolites of phase I reactions are sufficiently polar, they may be excreted at this point. However, many phase I products are not eliminated and undergo a subsequent reaction in which an endogenous substrate combines with the newly incorporated functional group to
Route of administration
A route of administration in pharmacology and toxicology is the path by which a drug, poison, or other substance is taken into the body. Routes of administration are classified by the location at which the substance is applied. Common examples include intravenous administration. Routes can be classified based on where the target of action is. Action may be enteral, or parenteral. Route of administration and dosage form are aspects of drug delivery. Routes of administration are classified by application location; the route or course the active substance takes from application location to the location where it has its target effect is rather a matter of pharmacokinetics. Exceptions include the transdermal or transmucosal routes, which are still referred to as routes of administration; the location of the target effect of active substances are rather a matter of pharmacodynamics. An exception is topical administration, which means that both the application location and the effect thereof is local. Topical administration is sometimes defined as both a local application location and local pharmacodynamic effect, sometimes as a local application location regardless of location of the effects.
Administration through the gastrointestinal tract is sometimes termed enteral or enteric administration. Enteral/enteric administration includes oral and rectal administration, in the sense that these are taken up by the intestines. However, uptake of drugs administered orally may occur in the stomach, as such gastrointestinal may be a more fitting term for this route of administration. Furthermore, some application locations classified as enteral, such as sublingual and sublabial or buccal, are taken up in the proximal part of the gastrointestinal tract without reaching the intestines. Enteral administration can be used for systemic administration, as well as local, such as in a contrast enema, whereby contrast media is infused into the intestines for imaging. However, for the purposes of classification based on location of effects, the term enteral is reserved for substances with systemic effects. Many drugs as tablets, capsules, or drops are taken orally. Administration methods directly into the stomach include those by gastric feeding tube or gastrostomy.
Substances may be placed into the small intestines, as with a duodenal feeding tube and enteral nutrition. Enteric coated tablets are designed to dissolve in the intestine, not the stomach, because the drug present in the tablet causes irritation in the stomach; the rectal route is an effective route of administration for many medications those used at the end of life. The walls of the rectum absorb many medications and effectively. Medications delivered to the distal one-third of the rectum at least avoid the "first pass effect" through the liver, which allows for greater bio-availability of many medications than that of the oral route. Rectal mucosa is vascularized tissue that allows for rapid and effective absorption of medications. A suppository is a solid dosage form. In hospice care, a specialized rectal catheter, designed to provide comfortable and discreet administration of ongoing medications provides a practical way to deliver and retain liquid formulations in the distal rectum, giving health practitioners a way to leverage the established benefits of rectal administration.
The parenteral route is any route, not enteral. Parenteral administration can be performed by injection, that is, using a needle and a syringe, or by the insertion of an indwelling catheter. Locations of application of parenteral administration include: central nervous systemepidural, e.g. epidural anesthesia intracerebral direct injection into the brain. Used in experimental research of chemicals and as a treatment for malignancies of the brain; the intracerebral route can interrupt the blood brain barrier from holding up against subsequent routes. Intracerebroventricular administration into the ventricular system of the brain. One use is as a last line of opioid treatment for terminal cancer patients with intractable cancer pain. Epicutaneous, it can be used both for local effect as in allergy testing and typical local anesthesia, as well as systemic effects when the active substance diffuses through skin in a transdermal route. Sublingual and buccal medication administration is a way of giving someone medicine orally.
Sublingual administration is. The word "sublingual" means "under the tongue." Buccal administration involves placement of the drug between the cheek. These medications can come in the form of films, or sprays. Many drugs are designed for sublingual administration, including cardiovascular drugs, barbiturates, opioid analgesics with poor gastrointestinal bioavailability and vitamins and minerals. Extra-amniotic administration, between the endometrium and fetal membranes nasal administration (th
European Chemicals Agency
The European Chemicals Agency is an agency of the European Union which manages the technical and administrative aspects of the implementation of the European Union regulation called Registration, Evaluation and Restriction of Chemicals. ECHA is the driving force among regulatory authorities in implementing the EU's chemicals legislation. ECHA helps companies to comply with the legislation, advances the safe use of chemicals, provides information on chemicals and addresses chemicals of concern, it is located in Finland. The agency headed by Executive Director Bjorn Hansen, started working on 1 June 2007; the REACH Regulation requires companies to provide information on the hazards and safe use of chemical substances that they manufacture or import. Companies register this information with ECHA and it is freely available on their website. So far, thousands of the most hazardous and the most used substances have been registered; the information is technical but gives detail on the impact of each chemical on people and the environment.
This gives European consumers the right to ask retailers whether the goods they buy contain dangerous substances. The Classification and Packaging Regulation introduces a globally harmonised system for classifying and labelling chemicals into the EU; this worldwide system makes it easier for workers and consumers to know the effects of chemicals and how to use products safely because the labels on products are now the same throughout the world. Companies need to notify ECHA of the labelling of their chemicals. So far, ECHA has received over 5 million notifications for more than 100 000 substances; the information is available on their website. Consumers can check chemicals in the products. Biocidal products include, for example, insect disinfectants used in hospitals; the Biocidal Products Regulation ensures that there is enough information about these products so that consumers can use them safely. ECHA is responsible for implementing the regulation; the law on Prior Informed Consent sets guidelines for the import of hazardous chemicals.
Through this mechanism, countries due to receive hazardous chemicals are informed in advance and have the possibility of rejecting their import. Substances that may have serious effects on human health and the environment are identified as Substances of Very High Concern 1; these are substances which cause cancer, mutation or are toxic to reproduction as well as substances which persist in the body or the environment and do not break down. Other substances considered. Companies manufacturing or importing articles containing these substances in a concentration above 0,1% weight of the article, have legal obligations, they are required to inform users about the presence of the substance and therefore how to use it safely. Consumers have the right to ask the retailer whether these substances are present in the products they buy. Once a substance has been identified in the EU as being of high concern, it will be added to a list; this list is available on ECHA's website and shows consumers and industry which chemicals are identified as SVHCs.
Substances placed on the Candidate List can move to another list. This means that, after a given date, companies will not be allowed to place the substance on the market or to use it, unless they have been given prior authorisation to do so by ECHA. One of the main aims of this listing process is to phase out SVHCs where possible. In its 2018 substance evaluation progress report, ECHA said chemical companies failed to provide “important safety information” in nearly three quarters of cases checked that year. "The numbers show a similar picture to previous years" the report said. The agency noted that member states need to develop risk management measures to control unsafe commercial use of chemicals in 71% of the substances checked. Executive Director Bjorn Hansen called non-compliance with REACH a "worry". Industry group CEFIC acknowledged the problem; the European Environmental Bureau called for faster enforcement to minimise chemical exposure. European Chemicals Bureau Official website
The Jmol applet, among other abilities, offers an alternative to the Chime plug-in, no longer under active development. While Jmol has many features that Chime lacks, it does not claim to reproduce all Chime functions, most notably, the Sculpt mode. Chime requires plug-in installation and Internet Explorer 6.0 or Firefox 2.0 on Microsoft Windows, or Netscape Communicator 4.8 on Mac OS 9. Jmol operates on a wide variety of platforms. For example, Jmol is functional in Mozilla Firefox, Internet Explorer, Google Chrome, Safari. Chemistry Development Kit Comparison of software for molecular mechanics modeling Jmol extension for MediaWiki List of molecular graphics systems Molecular graphics Molecule editor Proteopedia PyMOL SAMSON Official website Wiki with listings of websites and moodles Willighagen, Egon. "Fast and Scriptable Molecular Graphics in Web Browsers without Java3D". Doi:10.1038/npre.2007.50.1
National Health Service
The NHS in England, NHS Scotland, NHS Wales, the affiliated Health and Social Care in Northern Ireland were established together in 1948 as one of the major social reforms following the Second World War. The founding principles were that services should be comprehensive and free at the point of delivery; each service provides a comprehensive range of health services, free at the point of use for people ordinarily resident in the United Kingdom, apart from dental treatment and optical care. Dr Somerville Hastings, President of the Socialist Medical Association proposed a resolution at the 1934 Labour Party Conference that the party should be committed to the establishment of a State Health Service. Conservative MP and Health Minister, Henry Willink, first proposed the National Health Service in 1944 with the publication of a White Paper "A National Health Service", distributed in full and short versions as well as in newsreel by Henry Willink himself. Henry Willink's National Health Service received cross party support and became Westminster legislation for England and Wales from 1946 and Scotland from 1947, the Northern Ireland Parliament's Public Health Services Act 1947.
NHS Wales was split from NHS in 1969 when control was passed to the Secretary of State for Wales before transferring to the Welsh Executive and Assembly under devolution in 1999. Calls for a "unified medical service" can be dated back to the Minority Report of the Royal Commission on the Poor Law in 1909, but it was following the 1942 Beveridge Report's recommendation to create "comprehensive health and rehabilitation services for prevention and cure of disease" that cross-party consensus emerged on introducing a National Health Service of some description; when Clement Attlee's Labour Party won the 1945 election he appointed Aneurin Bevan as Health Minister. Bevan embarked upon what the official historian of the NHS, Charles Webster, called an "audacious campaign" to take charge of the form the NHS took; the NHS was born out of the ideal that good healthcare should be available to all, regardless of wealth. Although being accessible regardless of wealth maintained Henry Willink's principle of free healthcare for all, Conservative MPs were in favour of maintaining local administration of the NHS through existing arrangements with local authorities fearing that an NHS which owned hospitals on a national scale would lose the personal relationship between doctor and patient.
Conservative MPs voted in favour of their amendment to Bevan's Bill to maintain local control and ownership of hospitals and against Bevan's plan for national ownership of all hospitals. The Labour government defeated Conservative amendments and went ahead with the NHS as it remains today. Bevan's principle of ownership with no private sector involvement has since been diluted, with Labour governments implementing large scale financing arrangements with private builders in private finance initiatives and joint ventures. At its launch by Bevan on 5 July 1948 it had at its heart three core principles: That it meet the needs of everyone, that it be free at the point of delivery, that it be based on clinical need, not ability to pay. Three years after the founding of the NHS, Bevan resigned from the Labour government in opposition to the introduction of charges for the provision of dentures and glasses; the following year, Winston Churchill's Conservative government introduced prescription charges.
These charges were the first of many controversies over reforms to the NHS throughout its history. From its earliest days, the cultural history of the NHS has shown its place in British society reflected and debated in film, TV, cartoons and literature; the NHS had a prominent slot during the 2012 London Summer Olympics opening ceremony directed by Danny Boyle, being described as "the institution which more than any other unites our nation". Each of the UK's health service systems operates independently, is politically accountable to the relevant government: the Scottish Government. NHS Wales was part of the same structure as that of England until powers over the NHS in Wales were firstly transferred to the Secretary of State for Wales in 1969 and thereafter, in 1999, to the Welsh Assembly as part of Welsh devolution; some functions may be performed by one health service on behalf of another. For example, Northern Ireland has no high-security psychiatric hospitals and depends on hospitals in Great Britain at Carstairs hospital in Scotland for male patients and Rampton Secure Hospital in England for female patients.
Patients in North Wales use specialist facilities in Manchester and Liverpool which are much closer than facilities in Cardiff, more routine services at the Countess of Chester Hospital. There have been issues about cross-border payments. Taken together, the four National Health Services in 2015–16 employed around 1.6 million people with a combined budget of £136.7 billion. In 2014 the total health sector workforce across the UK was 2,165,043; this broke down into 1,789,586 in England, 198,368 in Scotland, 110,292 in Wales and 66,797 in Northern Ireland. In 2017, there were 691,000 nurses registered in the UK, down 1,783 from the previous year. However, this is the first time nursing numbers have fallen since 2008. Although there has been increasing policy divergence between the four National Health Services in the UK, it can b
Excretion is a process by which metabolic waste is eliminated from an organism. In vertebrates this is carried out by the lungs and skin; this is in contrast with secretion, where the substance may have specific tasks after leaving the cell. Excretion is an essential process in all forms of life. For example, in mammals urine is expelled through the urethra, part of the excretory system. In unicellular organisms, waste products are discharged directly through the surface of the cell. During life activities such as cellular respiration, several chemical reactions take place in the body; these are known as metabolism. These chemical reactions produce waste products such as carbon dioxide, salts and uric acid. Accumulation of these wastes beyond a level inside the body is harmful to the body; the excretory organs remove these wastes. This process of removal of metabolic waste from the body is known as excretion. Green plants produce carbon water as respiratory products. In green plants, the carbon dioxide released during respiration gets utilized during photosynthesis.
Oxygen is a by product generated during photosynthesis, exits through stomata, root cell walls, other routes. Plants can get rid of excess water by guttation, it has been shown that the leaf acts as an'excretophore' and, in addition to being a primary organ of photosynthesis, is used as a method of excreting toxic wastes via diffusion. Other waste materials that are exuded by some plants — resin, latex, etc. are forced from the interior of the plant by hydrostatic pressures inside the plant and by absorptive forces of plant cells. These latter processes do not need added energy, they act passively. However, during the pre-abscission phase, the metabolic levels of a leaf are high. Plants excrete some waste substances into the soil around them. In animals, the main excretory products are carbon dioxide, urea, uric acid and creatine; the liver and kidneys clear many substances from the blood, the cleared substances are excreted from the body in the urine and feces. Aquatic animals excrete ammonia directly into the external environment, as this compound has high solubility and there is ample water available for dilution.
In terrestrial animals ammonia-like compounds are converted into other nitrogenous materials as there is less water in the environment and ammonia itself is toxic. Birds excrete their nitrogenous wastes as uric acid in the form of a paste. Although this process is metabolically more expensive, it allows more efficient water retention and it can be stored more in the egg. Many avian species seabirds, can excrete salt via specialized nasal salt glands, the saline solution leaving through nostrils in the beak. In insects, a system involving Malpighian tubules is utilized to excrete metabolic waste. Metabolic waste diffuses or is transported into the tubule, which transports the wastes to the intestines; the metabolic waste is released from the body along with fecal matter. The excreted material may be called ejecta. In pathology the word ejecta is more used. UAlberta.ca, Animation of excretion Brian J Ford on leaf fall in Nature