Persius/hicric huggingface dataset:
Nasal bone

# Overview
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their junction, "the bridge" of the nose.
Each has two surfaces and four borders.

# Surfaces
The outer surface is concavoconvex from above downward, convex from side to side; it is covered by the Procerus and Compressor naris, and perforated about its center by a foramen, for the transmission of a small vein.
The inner surface is concave from side to side, and is traversed from above downward, by a groove for the passage of a branch of the nasociliary nerve.

# Articulations
The nasal articulates with four bones: two of the cranium, the frontal and ethmoid, and two of the face, the opposite nasal and the maxilla.

# Additional images
- Orbital bones
- Lateral wall of nasal cavity, showing ethmoid bone in position.
- Articulation of nasal and lacrimal bones with maxilla.
- Right nasal bone. Outer surface.
- Right nasal bone. Inner surface.
- Sphenoid bone visible center right.
- Side view of the skull.
- The skull from the front.
- Horizontal section of nasal and orbital cavities.
- Medial wall of left orbit.
- Sagittal section of skull.
- Roof, floor, and lateral wall of left nasal cavity.
Nasal hair

# Overview
Nasal hair, or Nose hair is the hair in the nose. Adult humans have hairs in the anterior nasal passage. These hairs act as a fibrous filter for inhaled particles. Diffusion of ultra fine particles to the nasal hair occurs mostly for particles < 5 nm. Nasal hair has important implications for the health of the human body because a lack of nasal hair could invite the transport of potentially harmful particles into the respiratory system.
Nasal hair should not be confused with cilia of the nasal cavity, which are the microscopic cellular strands that, unlike macroscopic nasal hair, draw mucus up toward the oropharynx via their coordinated, back-and-forth beating.

# Nasal Hair and Attraction
In some cultures, nose hair protruding from the nostrils may be thought of as unattractive, as is hair protruding from one's ears. A number of devices have been sold to trim the nose hair, including miniature rotary clippers and attachments for electric shavers. However, given the function of nasal hairs, many physicians recommend trimming them lightly, if at all.

# Footnotes
Navel lint
Navel lint, or more commonly belly button lint or navel fluff, is an accumulation of fluffy fibres in one's navel.
Many people find that, at the beginning and end of the day, a small lump of fluff has appeared in the navel cavity. The reasons for this have been the subject of idle speculation for many years but in 2001, Dr. Karl Kruszelnicki of the University of Sydney, Australia, undertook a systematic survey to determine the ins and outs of navel lint. His primary findings were as follows:
- Navel lint consists primarily of stray fibers from one's clothing, mixed with some dead skin cells and strands of body hair.
- Contrary to expectations, navel lint appears to migrate upwards from underwear rather than downwards from shirts or tops. The migration process is the result of the frictional drag of body hair on underwear, which drags stray fibers up into the navel.
- Women experience less navel lint because of their finer and shorter body hairs. Conversely, older men experience it more because of their coarser and more numerous hairs.
- Navel lint's characteristic blue-gray tint is likely the averaging of the colors of fibers present in clothing; the same color as clothes dryer lint.
- The existence of navel lint is entirely harmless, and requires no corrective action.
Dr. Kruszelnicki was awarded the Ig Nobel Prize for Interdisciplinary Research in 2002.
David Hamilton, a Toronto native, has been an avid belly button lint enthusiast for years. Travelling to many different conferences and conventions worldwide, David has become the world's foremost expert and now holds the largest private collection of Human Navel Lint. He is currently working on developing his thesis on the nutritional benefits of ingesting navel lint.
Graham Barker of Perth, Western Australia, is in the Guinness Book of Records as the record holder for collecting navel lint. He has been collecting navel lint almost every day for over 20 years since 17th January 1984. He collects about 3.03 mg per day. Contrary to the research of Dr. Kruszelnicki, his lint is in a particular shade of red, even though he rarely wears red clothes.
Necrophagy

# Overview
Necrophagy is the act of feeding on corpses or carrion that were not killed to be eaten by the predator or others of its species. The word is derived from Ancient Greek "nekros" meaning corpse or dead and "phagos" meaning to eat.
Animals who partially or completely feed on dead animals that they have not predated are usually called scavengers, most familiar examples being hyenas and vultures. Also many insects use decayed matter as a protein source, e.g. some bee species or dung beetles.
With regard to carrion from the same species, the behavior is also referred to as anthropophagy, in the case of humans, or cannibalism, in the case of other non-human animals.
In humans, necrophagy is a taboo in most societies. In the Qur'an slanderers are stigmatized as those who eat the flesh of the dead body of the person they slander. The Aghori, a Hindu sect known to live in graveyards, according to a Persian source and nineteenth century British accounts, were necrophagous. There have been many instances in history, especially in war times, where necrophagy was a survival behavior.
de:Nekrophagie
Nerve root
A nerve root is the initial segment of a nerve leaving the central nervous system. It can refer to:
- A cranial nerve root, the beginning of one of the eleven pairs leaving the central nervous system from the brain stem or the highest levels of the spinal cord;
- A spinal nerve root, the beginning of one of the thirty-one pairs oleaving the central nervous system from the spinal cord. Each spinal nerve root consists of the union of a sensory dorsal root and a motor ventral root.
NeuroNames
NeuroNames is a system of nomenclature for the human and/or macaque brain.
It is maintained by the University of Washington and is a part of a tool called "BrainInfo".  BrainInfo helps one identify structures in the brain.  One can either search by a structure name or locate a structure in the brain atlas and get information such as its location in the classical brain hierarchy, other names used for the structure, the name in several languages, images of the structure, what cells it has, connectivity information and genes expressed there.
Currently, NeuroNames contains more than 15,000 neuroanatomical terms(and the number keeps increasing).  In addition, it defines more than 1,500 other neuroanatomical entities.
It is a component of the Metathesaurus of the Unified Medical Language System.
Neurotoxin

# Overview
A neurotoxin is a toxin that acts specifically on nerve cells  neurons  usually by interacting with membrane proteins such as  ion channels. Many of the venoms and other toxins that organisms use in defense against vertebrates are neurotoxins. A common effect is paralysis, which sets in very rapidly. The venom of bees, scorpions, pufferfish, spiders and snakes can contain many different toxins. Many neurotoxins act by affecting voltage-dependent ion channels. For example, tetrodotoxin and batrachotoxin affect sodium channels, maurotoxin, agitoxin, charybdotoxin, margatoxin, slotoxin, scyllatoxin and hefutoxin act on potassium channels, and calciseptine, taicatoxin and calcicludine act on calcium channels.
Toxins ingested from the environment are described as exogenous and include gases (such as carbon monoxide), metals (such as mercury), liquids (ethanol) and an endless list of solids.
When exogenous toxins are ingested, the effect on neurons is largely dependent on dosage. Thus, ethanol (alcohol) is inebriating in low doses, only producing mild neurotoxicity. Prolonged exposure to "safe" alcohol levels slowly weakens and kills neurons.
Neurotoxicity also occurs from substances produced within the body - endogenous neurotoxins. A prime example of a neurotoxin in the brain is glutamate, which is paradoxically also a primary neurotransmitter. When the glutamate concentration around a neuron reaches a critical point the neuron kills itself by a process called apoptosis. This whole process is called excitotoxicity, so named because glutamate normally acts as an excitatory neurotransmitter at lower levels.
A potent neurotoxin such as batrachotoxin affects the nervous system by causing depolarization of nerve and muscle fibres due to increased sodium ion permeability of the excitable cell membrane.
A number of artificial neurotoxins, known as nerve agents, have been developed for use as chemical weapons.
A very potent neurotoxin is tetrodotoxin.  This chemical acts to block sodium channels in neurons, preventing action potentials.  This leads to paralysis and eventually death (Wski)
Neutrospec
NeutroSpec (Technetium fanolesomab) is a monoclonal antibody manufactured by Palatin Technologies and used in radiological imaging.

# History and Use
NeutroSpec was approved by the FDA in June 2004 for imaging of patients with symptoms of appendicitis.  It consisted of a monoclonal antibody against CD15.  The antibody was labeled with technetium-99 so as to be visible on a gamma camera.  Since anti-CD15 antibodies bind selectively to Neutrophils it could be used to localize the site of an infection.

# Deaths and Associated Recall
The FDA received reports from Palatin Technologies of 2 deaths and 15 additional life-threatening adverse events in patients receiving NeutroSpec.  These events occurred within minutes of administration of NeutroSpec and included shortness of breath, low blood pressure, and cardiopulmonary arrest. Affected patients required resuscitation with intravenous fluids, blood pressure support, and oxygen. Most, but not all, of the patients who experienced these events had existing cardiac and/or pulmonary conditions that may have placed them at higher risk for these adverse events. A review of all post-marketing reports showed an additional 46 patients who experienced adverse events that were similar but less severe. All of the reactions occurred immediately after NeutroSpec was administered.
Marketing of the product was suspended in December of 2005.
Niaprazine

# Overview
Niaprazine (Nopron) is a sedative-hypnotic drug of the phenylpiperazine class. It has been used in the treatment of sleep disturbances since the early 1970s in several European countries, including France, Italy, and Luxembourg. It is commonly used with children and adolescents on account of its favorable safety and tolerability profile and lack of abuse potential.
Originally believed to act as an antihistamine and anticholinergic, niaprazine was later discovered to have no significant binding affinity for either the H1 or the mACh receptors (Ki = > 1 M), and was instead found to act as a potent and selective 5-HT2A and 1-adrenergic receptor antagonist (Ki = 75 nM and 86 nM, respectively). It is virtually inactive at 5-HT1A, 5-HT2B, D2, and -adrenergic, as well as at SERT and VMAT (Ki = all > 1 M), but it does have some weak affinity for the 2-adrenergic receptor (Ki = 730 nM), likely acting as an antagonist there as well.
Niaprazine has been shown to metabolize to the compound pFPP in a similar manner to how trazodone and nefazodone metabolize to mCPP. It is unclear what role, if any, pFPP plays in the clinical effects of niaprazine. However, from animal studies it is known that pFPP, unlike niaprazine, does not produce sedative effects, and instead exerts a behavioral profile indicative of serotonergic activation.
Nicorandil

# Overview
Nicorandil is a drug used to treat angina. It is marketed under the trade names Ikorel (in the United Kingdom, Australia and most of Europe), Zynicor (in India) and Sigmart (in Japan, South Korea and Taiwan). Nicorandil is not available in the United States.

# Mechanism of Action
Nicorandil acts by relaxing the smooth muscle of the blood vessels, especially those of the venous system. It does this through two methods. Firstly, by activating  potassium channels, and secondly by donating nitric oxide to activate the enzyme guanylate cyclase. Guanylate cyclase causes activation of GMP leading to both arterial and venous vasodilatation. As it is selective for vascular potassium channels, it has no significant action on cardiac contractility and conduction.
Although it can dilate the coronary vessels of a healthy individual, its effects on the coronary vessels of someone with ischaemic heart disease will be little as they will already be completely dilated. Instead, it dilates the venous system, reducing preload and the work of the heart.

# Side Effects
Common side effects include flushing, palpitation, weakness, headache, mouth ulcers, nausea and vomiting. More recently peri-anal, ileal and peri-stomal ulceration has been reported as a side effect. Anal ulceration is now included in the British National Formulary as a recognised side effect.
Nifurtimox

# Overview
Nifurtimox is a 5-nitrofuran and is used to treat diseases caused by trypanosomes (Chagas disease and sleeping sickness).  It is given by mouth and not by injection.

# Uses
Nifurtimox has been used to treat Chagas disease, when it is given for 30 to 60 days, but gastrointestinal and neurological side effects have meant that benznidazole is now preferred for that indication.
Nifurtimox has also been used to treat African sleeping sickness and is active in the second stage of African sleeping sickness (CNS disease).  Unfortunately, when nifurtimox is given on its own, about half of all patients will relapse, but the combination of melarsoprol with nifurtimox appears to be efficacious.  Trials are awaited comparing melarsoprol/nifurtimox against melarsoprol alone for African sleeping sickness.

# Dosing
Nifurtimox is dosed as 15 mg/kg/day in two to three divided doses.  It is given by mouth.  Refer to the articles on Chagas disease and sleeping sickness for more detailed information on dosing for these diseases.

# Manufacturing and availability
Nifurtimox is sold as Lampit by Bayer.  It was previously known as Bayer 2502.
Nifurtimox is only licensed for use in Argentina and Germany, where it is sold as 120 mg tablets.
Nociceptor

# Overview
A nociceptor is a sensory receptor that sends signals that cause the perception of pain in response to potentially damaging stimulus. Nociceptors are the nerve endings responsible for nociception, one of the two types of persistent pain (the other, neuropathic pain, occurs when nerves in the central or peripheral nervous system are not functioning properly). When they are activated, nociceptors can trigger a reflex.

# Location
Nociceptors are sensory neurons that are found in external tissues such as skin, cornea and mucosa as well as in internal organs, such as the muscle, joint, bladder and gut. The cell bodies of these neurons are located in either the dorsal root ganglia or the trigeminal ganglia.

# Types and functions
There are several types of nociceptors and they are classified according to the stimulus modalities to which they respond: i.e. thermal, mechanical or chemical. Some nociceptors respond to more than one of these modalities and are consequently designated polymodal. Other nociceptors respond to none of these modalities (although they may respond to stimulation under conditions of inflammation) and have thereby earned the more poetic title of sleeping or silent nociceptors (Kandel et al, 2000). Thermal nociceptors are activated by noxious heat or cold, temperatures above 45C and below 5C (Kandel et al, 2000). Mechanical nociceptors respond to excess pressure or mechanical deformation. Polymodal nociceptors respond to damaging stimuli of a chemical, thermal, or mechanical nature (Kandel et al, 2000). Nociceptors may have either A fiber axons or more slowly conducting C fiber axons. Thus, pain often comes in two phases, the first mediated by the fast-conducting A fibers and the second part due to C fibers. Silent nociceptors do not usually fire action potentials, though they are much more likely to do so in the presence of inflammation or damaging chemicals (Kandel et al, 2000). Together these nociceptors allow the organism to feel pain in response to damaging pressure, excessive heat, excessive cold and a range of chemicals, the majority of which are damaging to the tissue surrounding the nociceptor.

# Pathway
Afferent nociceptive fibers (those that send information to, rather than from the brain) travel back to the spinal cord where they form synapses in its dorsal horn. The cells in the dorsal horn are divided into physiologically distinct layers called laminae. Different fiber types form synapses in different layers. A fibers form synapses in laminae I and V, C fibers connect with neurons in lamina II, A fibers connect with lamina I, III, & V. Information is then sent from the spinal cord to the thalamus and the cerebral cortex in the brain.
Nucleobase
Nucleobases (or Nucleotide bases) are the parts of RNA and DNA that may be involved in pairing (see also base pairs). These include cytosine, guanine, adenine, thymine (DNA) and uracil (RNA). These are abbreviated as C, G, A, T, and U, respectively. They are usually simply called bases in genetics. Because A, G, C, and T appear in the DNA, these molecules are called DNA-bases; A, G, C, and U are called RNA-bases, respectively.
Uracil replaces thymine in RNA. These two bases are identical except that uracil lacks the 5' methyl group. Adenine and guanine belong to the double-ringed class of molecules called purines (abbreviated as R). Cytosine, thymine, and uracil are all pyrimidines (abbreviated as Y).
A base covalently bound to the 1' carbon of a ribose or deoxyribose is called a nucleoside, and a nucleoside with one or more phosphate groups attached at the 5' carbon is called a nucleotide.
Apart from adenosine (A), cytidine (C), guanosine (G), thymidine (T) and uridine (U), DNA and RNA also contain bases that have been modified after the nucleic acid chain has been formed. In DNA, the only modified base is 5-methylcytidine (m5C). In RNA, there are many modified bases, including pseudouridine (), dihydrouridine (D), inosine (I), ribothymidine (rT) and 7-methylguanosine (m7G).
Hypoxanthine and xanthine are two of the many bases created through mutagen presence, both of them through deamination (replacement of the amine-group with a hydroxyl-group). Hypoxanthine is produced from adenine, xanthine from guanine. Similarly, deamination of cytosine results in uracil.

# Structure
- The "skeleton" of adenine and guanin is purine, hence the name purine-bases.
- The "skeleton" of cytosine, uracil and thymine is pyrimidine, hence pyrimidine-bases.

## Main bases
These are incorporated into the growing chain during RNA and/or DNA synthesis.

## Modified purine bases
These are examples of modified adenosine or guanosine.

## Modified pyrimidine bases
These are examples of modified cytidine, thymidine or uridine.

# Novel Bases
A vast number of nucleobases analogues exist.
The most common application are used as fluorescent probes, either directly or indirectly, such as Aminoallyl nucleotide which are used to label cRNA or cDNA in microarrays.
Several groups are working on alternative "extra" base pairs to extend the genetic code, such as isoguanine and isocytosine or the fluorescent 2-amino-6-(2-thienyl)purine and pyrrole-2-carbaldehyde.
In medicine, several nucleoside analogues are used as anticancer and antiviral agents. The viral polymerase incorporates these compounds with non-canon bases. These compounds are activated in the cells by being converted into nucleotides, they are adminisered as nuclosides as charged nucleotides cannot easily cross cell membranes.
Nucleoside

# Overview
Nucleosides are glycosylamines made by attaching a nucleobase (often referred to simply as base) to a ribose or deoxyribose ring. Examples of these include cytidine, uridine, adenosine, guanosine, thymidine and inosine. In short, a nucleoside is a base linked to sugar.
Nucleosides can be phosphorylated by specific kinases in the cell, producing nucleotides, which are the molecular building blocks of DNA and RNA.
Nucleosides are produced as the second step in nucleic acid digestion, whereby nucleotidases break down nucleotides (such as the thymine nucleotide) into nucleosides (such as thymidine) and phosphate. The nucleosides, in turn, are subsequently broken down
- in the lumen of the digestive system by nucleosidases into nitrogenous bases and ribose (or deoxyribose), and
- inside the cell by nucleoside phosphorylases into nitrogenous bases, and ribose-1-phosphate (or deoxyribose-1-phosphate).
Nucleosides can be produced by combining nucleobases with deoxyribose rings as well.
Nucleosides differ from nucleotides by having a hydroxyl group attached to carbon number 5 (the one that isn't in the ring) of the ribose, rather than one or more phosphate groups.
In medicine several nucleoside analogues are used as antiviral or anticancer agents. The viral polymerase incorporates these compounds with non-canon bases. These compounds are activated in the cells by being converted into nucleotides, they are administered as nuclosides since charged nucleotides cannot easily cross cell membranes.
In molecular biology several analogues of the sugar back bone exist. Due to the low stability of RNA, which is prone to hydrolysis, several more stable alternative nucleoside/nucleotide analogues are used which correctly bind to RNA. This is achieved by using a different backbone sugar. These analogues includ LNA, morpholino, PNA.
In sequencing dideoxynucleotides are used. These nucleotides posses a non-canon sugar, dideoxyribose which lacks 3' hydroxyl group (which accepts the phosphate) and therefore cannot bond with the next base, terminating the chain as DNA polymerases mistake it for a regular deoxyribonucleotide.
Nutmeg oil
Nutmeg oil is a volatile oil containing borneol and eugenol.

# General uses
The essential oil is obtained by the steam distillation of ground nutmeg and is used heavily in the perfumery and pharmaceutical industries.
The oil is colorless or light yellow and smells and tastes of nutmeg. It contains numerous components of interest to the oleochemical industry, and is used as a natural food flavouring in baked goods, syrups (e.g. Coca Cola), beverages, sweets etc. It replaces ground nutmeg as it leaves no particles in the food. The essential oil is also used in the cosmetic and pharmaceutical industries for instance in tooth paste and as a major ingredient in some cough syrups. In traditional medicine nutmeg and nutmeg oil were used for illnesses related to the nervous and digestive systems. Myristicin in the essential oil is probably the agent responsible for the hallucinogenic properties of nutmeg oil.

# External uses
Externally, the oil is used for rheumatic pain and, like clove oil, can be applied as an emergency treatment to dull toothache. In France, it is given in drop doses in honey for digestive upsets and used for bad breath. 
Put 1-2 drops on a cotton swab, and apply to the gums around an aching tooth until dental treatment can be obtained. Use 3-5 drops on a sugar lump or in a teaspoon of honey for nausea, gastroenteritis, chronic diarrhea, and indigestion.
Alternatively a massage oil can be created by diluting 10 drops in 10 ml almond oil. This can be used for muscular pains associated with rheumatism or overexertion. It can also be combined with thyme or rosemary essential oils. To prepare for childbirth, massage the abdomen daily in the three weeks before the baby is due with a mixture of 5 drops nutmeg oil and no more than 5 drops sage oil in 25 ml almond oil.