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AMR's answer is excellent and deserves praise. I only want to add that, scientifically (NOT therapeutically) there may be other ways to prevent infection. A Nature letter from 2012 examined the role migratory T-cells play in HIV infection. They used a drug, FTY720, also known as fingolimod, which essentially kept lymphocytes from moving out of lymph nodes. ...


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Seminal fluid dries out very quickly when it's outside the body - and once it's dried, the sperm die almost at once. How quickly it dries depends a lot on what the surface is. On a human hand, the drying/survival time would be very short.


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The female body responds to an orgasm by the contracting/pulsating of the vaginal walls. If the g-spot of the female's vagina is stimulated correctly, she can emit a clear fluid which is known as "squirting" but not every woman can do it as there are different ways some must be stimulated, but it's possible for her to do it if she is able to get the correct ...


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The standard protocol for treating a healthcare worker that accidentally comes in contact with HIV infected body fluid is to receive HAART treatment. HAART is an acronym that stands for Highly Active AntiRetroviral Therapy, and is a multi-drug cocktail that acts on a number of pathways to block the HIV virus from replicating. There are early inhibitors ...


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I think your supervisor wants to see if there is inter-cellular variation in the repeat length and if so, calculate the variation. This may be compared with inter-tissue or inter-individual variation. Usually when you take a pool of cells for any assay, you would average out the properties of individual cells. Using sequencing you may actually be able to ...


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Electricity directly stimulate neurons. You have to understand that neurons basically work via electric currents , which occur due to a difference in membrane charge. So when you give electricity to a neuron, you basically give electrons to the extracellular membrane, which makes it much more negative compared to the intracellular or the stuff that is inside ...


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I don't think this is a complete answer, but I know that historically hair, like horse tail has been used as a part of armor, because it is flexible and difficult to cut through (see dragoon helmet picture). Protection could be one of the primary purposes of facial hair in human males, who are more likely to experience aggression or be hunters.


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Electrical currents stimulate neurons aspecifically. For example, the BrainPort artificial vision device conveys information through electrical stimuluation of the tongue. Similarly, cochlear implants and retinal implants convey information through electrical stimulation of the inner ear and retina, respectively. The list goes on. Bottom line is, none of ...


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Simply, it's because of the mucous layer around the stomach, that prevents the strong acid, Hcl to hurt our stomach. Not only this, if there were no mucous, the Hcl would digest the protein present in the epithelial cells, so the stomach itself would get digested. So the main protagonist here is the mucous layer.


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If you are performing the fast for ritualistic or spiritual purposes, then that mental state likely overcomes the feeling of thirst or hunger, especially if you are an otherwise healthy person. As for the physiological aspects. The Human Body is made up of 2/3 water, and as your kidneys are still functional, they are constantly filtering, and creating ...


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The human body can last several days without food and (to a lesser degree) water, and often had to. I myself and certainly many others have not had to experience that tho, as modern Western society has pretty good countermeasures against this. After 24 hours, your body has still sufficient amounts of water, unless it was dehydrated earlier already. Contrary ...


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Our stomachs are lined with a special mucal layer which protects the organ from its own secretions. People with stomach ulcers have a hole in this layer, allowing the acid to get to the skin underneath. HCl is present in our stomach to aid digestion - especially with dismantaling the bolus (food) coming from the oesophagus. The HCl separates the larger bolus ...


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Goblet cells. These are specialized epithelial cells whose job it is to produce mucins. Mucous role is not only important in protecting the epithelium of the digestive tract from HCl, it is also a very important substance in the innate immune system, acting as a barrier defense to trap pathogens and/or prevent them from breaching the epithelium and gaining ...


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As a preface, this isn't a comprehensive answer for everything. As MattDMo points out, some of the original answer was poor in it's presentation. In my update there's some supporting information to some expert testimonial, but this is mainly targeted at adult cases rather than pediatric cases, i.e. why would cardiac cancer be rare in an adult with no prior ...


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From jzx's answer, I thought of a possible answer to my own question. Maybe not producing identical twins all the time is a paradoxical evolutionary stable strategy for the following reason: Until recently in evolutionary history, the population remained constant when parents only had enough food to feed 2 children. Siblings didn't evolve to be fully ...


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What you describe could have happened under the right conditions. However, there are a few things you haven't considered. Because humans are especially altricial, always having twins would double the cost of children on parents. The benefit of sexual reproduction is immune diversity. So a population like this could be far more vulnerable to disease. So ...


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If we produced identical twins all the time then we'd completely lose genetic diversity which would, I assume, overwhelmingly compromise our adaptive capabilities. Don't forget, those identical twins then need to reproduce with other identical twins of others families. Moreover, and this is the more obvious explanation, as a consequence deleterious recessive ...


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A good book to learn as background is called 'Why We Get Sick: The New Science of Darwinian Medicine'. In a sense you can consider us vectors for some microorganisms. When you cough you spread germs to other individuals (other vectors). Thus, it would be evolutionarily advantageous for a microorganism's genes if they were to infect more vectors. How many ...


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You have made an incorrect assumption-- that all the genes on both chromosomes necessarily remain intact. It's possible that they do, and the the translocation is harmless. But the transition point could be within a gene. This would usually lead to that copy of the gene becoming inactive, which can cause diseases just like any other loss-of-function ...


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In the Down syndrom typically, the translocation does not induce (usually; see later) any disease. We call someone carrying the translocation a "balanced carrier". The problem arises after, at the moment of segregation. When balanced carriers reproduce Consider someone who has a translocation as you showed. You showed only one chromosome of each types ...


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In order to keep the hair from decomposing, my first assumption is you'd need it in an environment that inhibits decomposers, e.g. dry. We can see in the mummification process that hair may be preserved for hundreds of years. Hair is also composed largely of keratin, however, and in my own search of the literature: (1) we need microbial (bacteria, fungi) ...


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As is stated in this article by Hiller-Sturmhöfel and Swartzwelder from the National Institute on Alcohol Abuse and Alcoholism, there are ethical issues surrounding research on human subjects that preclude direct testing, however studies in model mammals and observational studies do find that "adolescence is a unique stage of brain development which is ...


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How long human egg cell grow up until sperm fuse it? Ovules are made while the female is still in the uterus of her mother. The ovules (in the form of ovarian follicles) are kept in the ovaries for a long time, and just a month before leaving the ovary (ovulation), the ovarian follicle (and the future ovule) gain in size. In other words, the ovules are ...


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Answer While itching and pain are related, research indicates that these sensations are caused by distinct nociceptors. Essentially, wounds itch because histamine is released as part of the wound healing process, and histamine activates those itch nociceptors. So perhaps the more apt question is just "why does histamine cause itching?" (See also answer to ...


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Just to make this post a tiny bit more useful, I must add that there are several additional sources I've found: UniProt has an open dataset called humsavar ClinVar database HGMD database OMIM A paper with a manually collected database based on recent publications in Nature Genetics. Different datasets intersect to some extent, but all in all you get ...


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Yes, people can definitely grow taller than their parents. Height is a polygenic quantitative trait (so affected by many genes), that is also strongly affected by environmental factors. You are also forgetting that there is a sex difference in height (~14 cm, Wright & Cheetham, 1999), so the height of the mother does for instance not set an absolute cap ...


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The most accurate method known so far may be Horvath's methylation dating algorithm, which uses 353 CpG sites (Genome Biology research article, Nature news article). From the Nature article, this method was validated with at least one population. [After the publication in Genome Biology] Marco Boks at the University Medical Centre Utrecht in the ...


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The excellent answers from Chris and One Face have already written about why the claim is wrong, so I'm going to add a hypothesis for how this sort of nonsense could even originate in the first place. The reason why lemons are acidic is because they contain a lot of citric acid, so in a solution part of this citric acid ionizes to citrate which increases ...


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Sugar (be it sucrose, glucose, fructose or honey) does not have emetic properties in any concentration, unless there is a personal (and highly individual) psychological adverse reaction to sweet substances. Sugar is not a local gastric irritant (like dishwashing detergent, or syrup of ipecac, copper sulphate, zinc sulphate; yellow mercuric sulphate, ...


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The phenomenon you described as "my eyes seem to adjust" is a particular case of accommodation - adjustment of the dioptric power of the crystalline lens to the object's distance. When you place a lens before your eye, any object seen through this lens will initially appear at a different distance (and of different size of course) and will be blurred at ...



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