Persius/hicric huggingface dataset:
Group 4 element
In modern IUPAC nomenclature, Group 4 of the periodic table contains the following chemical elements:
- titanium (Ti)
- zirconium (Zr)
- hafnium (Hf)
- rutherfordium (Rf).
This group lies in the d-block of the periodic table. The group itself has not acquired a trivial name; it belongs to the broader grouping of the transition metals.
These elements are hard refractory metals. Titanium's mechanical properties make it useful in alloys. All isotopes of rutherfordium are radioactive, and have been synthesized in the laboratory, none of them have been found occurring in nature.

# Biological occurances
The group 4 elements are not known to be involved in the biological chemistry of any living systems. They are hard refractory metals with low acqueous solubility and low availability to the biosphere. Titanium is one of the few first row d-block transition metals with no known biological role. Rutherfordium's radioactivity would make it toxic to living cells.
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Group 5 element
A Group 5 element is one in the series of  elements in group 5 (IUPAC style) in the periodic table, which consists of vanadium (V), niobium (Nb), tantalum (Ta), and dubnium (Db).
All of these elements are classed in Group 5 because their valence shell holds five electrons.  Dubnium can only be produced in the laboratory, and does not exist in nature.

# Biological occurrences
Of the group 5 elements, only vanadium has been identified as playing a role in the biological chemistry of living systems: it is involved in some of the enzymes of higher organisms, and also, unusually, in the biochemistry of some marine tunicates.
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Hair prosthesis
A Hair prosthesis (or cranial prosthesis), is a custom-made wig specifically designed for patients who have lost their hair as a result of medical conditions or treatments, such as alopecia areata
, alopecia totalis, trichotillomania, chemotherapy, or any other clinical disease or treatment resulting in hair loss.. 
The terminology is used when applying for medical insurance or tax deduction status.
Doctors have been prescribing these prostheses since the 1950s.  Cranial prostheses also help to protect disease-weakened immune systems from the sun, and to regulate body temperature.
Haverhill fever
In rat-bite fever transmitted by the gram-negative rod Streptobacillus moniliformis, symptoms begin to appear two to ten days after a rat bite injury. The illness resembles a severe influenza, with a moderate fever (101-104 F), chills, joint pain, and a diffuse red rash, located mostly on the hands and feet. The causative organism can be isolated by blood culture, and penicillin is the most common treatment. Treatment is usually quite successful, although the body can clear the infection by itself in most cases. Complications are rare, but can include endocarditis and meningitis.
This form of rat-bite fever is known by the alternate names Haverhill Fever and epidemic arthritic erythema.
Despite its name, it can present without being bitten by a rat..
Hazardous drugs

# Overview
In pharmacology, hazardous drugs are drugs that are known to cause genotoxicity, which is the ability to cause a change or mutation in genetic material; carcinogenicity, the ability to cause cancer in animal models, humans or both; teratogenicity, which is the ability to cause defects on fetal development or fetal malformation; and lastly hazardous drugs are known to have the potential to cause fertility impairment, which is a major concern for most clinicians. These drugs can be classified as antineoplastics, cytotoxic agents, biologic agents, antiviral agents and immunosuppressive agents. This is why safe handling of hazardous drugs is crucial.

# Safe handling
Safe handling refers to the process in which health care workers adhere to evidence-based practices (EBP) set forth by national organizations, that have been designed to eliminate or significantly reduce occupational exposure. Some of these practices include but are not limited to, donning of personal protective equipment such as a disposable gown, gloves, masks and the utilization of a closed-system drug transfer device. The key to safe handling is to protect the health care worker throughout the three phases of contact with the hazardous drugs. These phases are drug preparation, administration and disposal. Research has shown that while compounding hazardous drugs in a Class II BSC in conjunction with a closed-system drug transfer device, a  significant decrease in drug contaminants inside a Class II BSC has resulted. The Oncology Nursing Society (ONS) further elaborates on the topic of safe handling by stating that a closed-system drug transfer device is viewed as one of safest measures to prevent hazardous drug exposure from coming in contact with a clinicians working environment.
It has been determined that current personal protective equipment (PPE) does not provide adequate protection against workers handling hazardous drugs - NIOSH states that ... measurable concentrations of some hazardous drugs have been documented in the urine of health care workers who prepared or administered them  even after safety precautions had been employed. Further, NIOSH recommends that institutions should "consider using devices such as closed-system transfer devices. Closed systems limit the potential for generating aerosols and exposing workers". Other guidelines outline that "As other products become available, they should meet the definition of a closed-system drug-transfer devices established by NIOSH and should be required to demonstrate their effectiveness in independent studies".
Heartland virus
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# Overview
The Heartland virus is a novel, tick-borne Phlebovirus discovered in northwestern Missouri by Dr. Scott Folk of Heartland Regional Medical Center in St. Joseph, Missouri.
The virus first appeared in humans in June 2009 when two farmers, living apart, presented with the following symptoms: fever, fatigue, diarrhea, thrombocytopenia, and leukopenia.
It is a member of the Bhanja virus serocomplex; the recently discovered SFTS virus from China is a related species causing a similar disease.
The virus has been traced by researchers from the CDC and Missouri Western State University back to the Lone Star Tick, which transmits the virus to people when feeding on blood.

# Characteristics
The Heartland virus is part of the Bunyaviridae family of viruses which contain 3 segments of -ssRNA. The genus of the virus is Phlebovirus and the species is the Heartland virus.

# Transmission
The Heartland virus has been isolated from the Lone Star Tick (Amblyomma americanum). The phleboviruses, in general, can be transmitted by mosquitoes, ticks and sand flies. Patients in all known cases of the Heartland virus in the United States reported being bitten by ticks in the previous 14 days.

# Signs and Symptoms
Fever in excess of 100.4F (38C), lethargy (weakness), headaches, myalgia (muscle pain), loss of appetite, nausea, diarrhea, weight loss, arthralgia (joint pain), leukopenia (low white blood cells) and thrombocytopenia (low platelets). Elevated liver transaminases may also be present.

# Risk Factors
All known cases reported in the United States have been reported in three states: Missouri, Tennessee, and Oklahoma.  Patients in all currently known cases spent a fair amount of time outdoors in regions where ticks were endemic. And, of these cases, all patients were above the age of 50. All cases occurred from May - September.

# Diagnosis
Diagnosis is currently through the elimination of other causes of infectious diseases with related symptoms like Ehrlichiosis and Anaplasmosis; or if the patient fails to respond to treatment with the antibiotic doxycycline. RT-PCR may then be used to detect viral ssRNA in the blood. Antibody titers against the virus may also be used to indicate infection with the Heartland virus.

# Treatment
Treatment is non-specific. Antibiotics are not useful against viruses. IV Fluid administration and medications for the relief of pain are currently the best options.

# Prevention
Use insect repellents on yourself and your gear. Completely cover your body with long sleeves and pants. Avoid bushy and wooded areas. Perform thorough tick checks after spending time outdoors and remove any tick found immediately.
If you encounter a tick on your body or your animal, remove the tick by the head. Squeezing the abdomen of a tick while it is attached can force bacteria and viruses into the bite wound. Squishing the unattached tick to kill it can release bacteria and viruses from the abdomen of the tick which may then be able to enter a wound or burrow through skin.

# Cases
Heberden's node

# Overview
Heberden's nodes - Named for William Heberden (1710-1801) - are hard or bony swellings which can develop in the distal interphalangeal joints (the furthest joints before the tips of the fingers or toes.) They are a sign of osteoarthritis, and are caused by formation of calcific spurs of the articular (joint) cartilage.

# Epidemiology and Demographics
Heberden's nodes are more common in women than in men, and there seems to be a genetic component involved in predisposition to the condition.

# Natural History, Complications and Prognosis
Heberden's nodes typically develop in middle age, beginning either with a chronic swelling of the affected joints or the sudden painful onset of redness, numbness, and loss of manual dexterity.
This initial inflammation and pain eventually subsides, and the patient is left with a permanent bony outgrowth that often skews the fingertip sideways. Bouchard's nodes may also be present; these are similar bony growths in the middle joints of the fingers, and are also associated with osteoarthritis.

# Physical Examination

## Extremities
- Heberden's nodes: Bony prominences at distal interphalangeal joints, seen  in some patients with osteoarthritis.
Hemiazygos vein
The hemiazygos vein (vena azygos minor inferior) is a vein running superiorly in the lower thoracic region, just to the left side of the vertebral column.

# Structure
The hemiazygos vein and the accessory hemiazygos vein, when taken together, essentially serve as the left-sided equivalent of the azygos vein.  That is, the azygos vein serves to drain most of the posterior intercostal veins on the right side of the body, and the hemiazygos vein and the accessory hemiazygos vein drain most of the posterior intercostal veins on the left side of the body.  Specifically, the hemiazygos vein mirrors the bottom part of the azygos vein.
The structure of the hemiazygos vein is often variable.  It usually begins in the left ascending lumbar vein or renal vein, and passes upward through the left crus of the diaphragm to enter the thorax.  It continues ascending on the left side of the vertebral column, and around the level of the ninth thoracic vertebra, it passes rightward across the column, behind the aorta, esophagus, and thoracic duct, to end in the azygos vein.
The hemiazygos may or may not be continuous superiorly with the accessory hemiazygos vein.
It receives the 9th, 10th, and 11th posterior intercostal veins and the subcostal vein of the left side, and some esophageal and mediastinal veins.

# Etymology
The name for this vein is derived from that of the azygos vein.  Azygos means 'unpaired', and hemi means half.  This vein mirrors the bottom half the azygos vein.
Hemihypertrophy

# Overview
Hemihypertrophy is a disease in which one side of the body or a part of one side is larger than the other. Isolated hemihypertrophy, now called isolated hemihyperplasia, is a congenital overgrowth disorder associated with an increased risk for embryonal tumors, mainly Wilms tumor and hepatoblastoma.   Children with hemihypertrophy may also develop scoliosis, a curvature of the spine.
There are two main surgical options for the treatment of hemihypertrophy, shortening and lengthening. Epiphysiodesis, which involves removing part of the growth plate of the longer leg, allowing the shorter leg to "catch up", is performed on patients still able to grow. Bone resection is performed on patients who have no growth left and involves removing part of the bone. Leg lengthening procedures are more painful, involving the insertion of pins to be turned, moving parts of the bone apart. This process is reserved mainly for patients with a discrepancy greater than 4 cm, although some leg lengthening procedures are now done cosmetically.
Non-surgical options include attachment of a lift to the shoe, allowing the patient to walk normally.
Hemifacial hyperplasia is believed to be a minor form of hemihypertrophy.
Hemispherectomy
Hemispherectomy is a surgical procedure where one cerebral hemisphere (half of the brain) is removed or disabled. This procedure is used to treat a variety of seizure disorders where the source of the epilepsy is localized to a broad area of a single hemisphere of the brain.  It is solely reserved for extreme cases in which the seizures have not responded to medications and other less invasive surgeries.

# History and changes
Hemispherectomy was first tried on a dog in 1888 by Friedrich Goltz. The first such operation on humans was done by Walter Dandy in 1923. In the 1960s and early 1970s, hemispherectomy involved removing half of the brain, but this resulted in unacceptable complications and side effects in many cases, like filling of excessive body fluids in the skull and pressuring the remaining lobe (known as hydrocephalus). Today, the functional hemispherectomy has largely replaced this procedure, in which only the temporal lobe is removed; a procedure known as corpus callosotomy is performed; and the frontal and occipital lobes disconnected.

# Results
All hemispherectomy patients suffer at least partial hemiplegia on the side of the body opposite the removed or disabled portion, and may suffer problems with their vision as well.
This procedure is almost exclusively performed in children, since their brains generally display more neuroplasticity, allowing neurons from the remaining hemisphere to take over the tasks from the lost hemisphere. This likely occurs by strengthening neural connections which already exist on the unaffected side but which would have otherwise remained small in a normally functioning, uninjured brain. One case, demonstrated by Smith & Sugar, 1975; A. Smith 1987, showed that one patient with this procedure had completed college, had attended graduate school and scored above average on intelligence tests. Studies have found no significant long-term effects on memory, personality, or humour after the procedure, and minimal changes in cognitive function overall. Generally, the greater the intellectual capacity of the patient prior to surgery; the greater the decline. Most patients end up with a mild to severe mental retardation, although this usually constitutes no change to intellectual function before surgery. When resection of the left hemisphere, there is some evidence indicating that some advanced language functions (i.e. higher order grammar) cannot be entirely assumed by the right side. The extent of this however being somewhat dependant of age at surgery.

# In the Media
A hemispherectomy is performed on a patient played by Dave Matthews in the Season 3 episode of House, M.D., "Half Wit." His right hemisphere was severely damaged in a car accident when he was 10 years old.
In the Season 1 episode called "The Self-Destruct Button" on Grey's Anatomy, Dr. Shepherd performs a hemispherectomy on a 2 year old girl with a seizure disorder.
Hemopericardium

# Overview
Hemopericardium refers to blood in the pericardial sac of the heart. It is a cause of pericardial effusion, and can also cause cardiac tamponade.
The condition can be caused by trauma, but it has also been observed in patients on anticoagulant therapy.

# Pathological Findings
Images courtesy of Professor Peter Anderson DVM PhD and published with permission  PEIR, University of Alabama at Birmingham, Department of Pathology
Hernia overview
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# Overview
A hernia is a protrusion of a tissue, structure, or part of an organ through the muscular tissue or the membrane by which it is normally contained. The hernia has 3 parts: the orifice through which it herniates, the hernial sac, and its contents. The contents, usually portions of intestine or abdominal fatty tissue, are enclosed in the thin membrane that naturally lines the inside of the cavity. a Hernia has a potential risk of having its blood supply cut off (becoming strangulated), and the contents may become necrotic due to the lack of oxygen supply.
A hernia may be likened to a failure in the sidewall of a pneumatic tire. The tire's inner tube behaves like the organ and the side wall like the body cavity wall providing the restraint. A weakness in the sidewall allows a bulge to develop, which can become a split, allowing the inner tube to protrude, and leading to the eventual failure of the tire.
Heroic medicine
Heroic medicine is a term for aggressive medical practices or methods of treatment, and usually refers to those which were later superseded by scientific advances.
It is not known who first used the pejorative term heroic medicine; but it is most likely that it was first used by US or British scholars of the history of medicine in the early years of the twentieth century.
Heroic medicine, in which the patient, rather than the physician (or the therapy) was heroic, flourished between the 1780s and 1850s. 
Benjamin Rush (17451813), who signed the American Declaration of Independence, and is considered to be one of the fathers" of American medicine, and who had trained in medicine at Edinburgh University (17661768), was a strong advocate of heroic medicine.
During the Age of Heroic Medicine (17801850), educated professional physicians aggressively practiced "heroic medicine," including bloodletting (venesection), intestinal purging (calomel), vomiting (tartar emetic), profuse sweating (diaphoretics) and blistering. Physicians originally treated diseases like syphilis with salves made from mercury. These medical treatments were well-intentioned, and often well-accepted by the medical community, but were actually harmful to the patient.
Heteropodatoxin

# Overview
Heteropodatoxins are peptide toxins from the venom of the giant crab spider Heteropoda venatoria, which block Kv4.2 voltage-gated potassium channels.

# Source
Heteropodatoxins are purified from the venom of the giant crab spider, Heteropoda venatoria Template:Harv.

# Chemistry
Heteropodatoxins contain an Inhibitory Cystin Knot (ICK) motif, which consist of a compact disulfide-bonded core, from which four loops emerge Template:Harv. There are three different heteropodatoxins Template:Harv:
- heteropodatoxin-1, also known as Toxin AU3/KJ5 or HpTx1
- heteropodatoxin-2, also known as Toxin KJ6 or HpTx2
- heteropodatoxin-3, also known as Toxin AU5C/KJ7 or HpTx3
These three toxins are structurally similar peptides of 29-32 amino acids Template:Harv. They show sequence similarity to Hanatoxins, which can be isolated from the venom of the Chilean rose tarantula Grammostola rosea Template:Harv.

# Target
Heteropodatoxins block A-type, transient voltage-gated potassium channels. All three toxins have been shown to block the potassium channel Kv4.2 Template:Harv. Recombinant heteropodatoxin-2 blocks the potassium channels Kv4.1, Kv4.2 and Kv4.3, but not Kv1.4, Kv2.1, or Kv3.4 Template:Harv.

# Mode of action
Heterpodatoxin-2 most likely acts as a gating modifier of the Kv4.2 channels Template:Harv.  It shifts the voltage dependence of the activation and the inactivation of the Kv4.3 potassium channel to more positive values. As a result, in the presence of the toxin this channel has a higher probability of being inactivated and a larger depolarization is needed to open the channel. However, heterpodatoxin-2 did not affect the voltage dependence of the Kv4.1 channel, suggesting that the precise mechanism of block remains to be elucidated Template:Harv and a role as a pore blocker cannot be excluded Template:Harv. The voltage dependence of Kv4.2 block varies among the three different heteropodatoxins. It is less voltage dependent for HpTx1 than for HpTx2 or HpTx3 Template:Harv.

# Toxicity
The giant crab spider can cause a locally painful bite .
Heteropoly acid
A heteropoly acid is a class of acid made up of a particular combination of hydrogen and oxygen with certain metals and non-metals.  This type of acid is frequently used as a re-usable acid catalyst in chemical reactions.
To qualify as a heteropoly acid, the compound must contain:
- a metal such as tungsten, molybdenum or vanadium, termed the addenda atom;
- oxygen;
- an element generally from the p-block of the periodic table, such as silicon, phosphorus or arsenic   termed the hetero atom;
- acidic hydrogen atoms.
The metal addenda atoms linked by oxygen atoms form a cluster with the hetero-atom inside bonded via oxygen atoms. Examples with more than one type of metal addenda atom in the cluster are well known. The conjugate anion of a heteropoly acid is known as a polyoxometalate.
Due to the possibilities of there being different combinations of addenda atoms and different types of hetero atoms there are a lot of heteropolyacids. Two of the better known groups of these are based on the Keggin, HnXM12O40, and Dawson, HnX2M18O62, structures.
Some examples are:
- H4Xn+M12O40, X = Si, Ge; M = Mo, W
- H3Xn+M12O40, X = P, As; M = Mo, W
- H6X2M18O62, X=P, As;M = Mo, W
The heteropolyacids are widely used as homogeneous and heterogeneous catalysts, particularly those based on the Keggin structure as they can possess qualities such as good thermal stability, high acidity and high oxidising ability. Some examples of catalysis are:
- Homogeneous acid catalysis
hydrolysis of propene to give propan-2-ol by H3PMo12O40 and H3PW12O40
Prins reaction by H3PW12O40
polymerisation of THF by H3PW12O40
- hydrolysis of propene to give propan-2-ol by H3PMo12O40 and H3PW12O40
- Prins reaction by H3PW12O40
- polymerisation of THF by H3PW12O40
- Heterogeneous acid catalysis
dehydration of propan-2-ol to propene and methanol to hydrocarbons by H3PW12O40
reformation of hexane to 2-methylpentane (isohexane) by  H3PW12O40 on SiO2
- dehydration of propan-2-ol to propene and methanol to hydrocarbons by H3PW12O40
- reformation of hexane to 2-methylpentane (isohexane) by  H3PW12O40 on SiO2
- Homogeneous oxidation
cyclohexene + H2O2 to adipic acid by the mixed addenda H3PMo6V6O40
ketone by O2 to acid and aldehyde by mixed addenda H5PMo10V2O40
- cyclohexene + H2O2 to adipic acid by the mixed addenda H3PMo6V6O40
- ketone by O2 to acid and aldehyde by mixed addenda H5PMo10V2O40
Heteropolyacids have long been used in analysis and histology and are a component of many reagents e.g. the Folin-Ciocalteu reagent, folins phenol reagent used in the Lowry protein assay and EPTA, ethanolic phosphotungstic acid.