# hypothesis

- A conjecture advanced for heuristic purposes,
*cast*in a*form*that is amenable to confirmation or refutation by the*conductance*of definable experiments and the*critical*assembly of*empiric**data*; not to be confused with*assumption*, postulation, or unfocused speculation. SEE ALSO:*postulate*,*theory*. [G.*foundation*,*assumption*fr. hypotithenai, to lay down]-**adaptor h.**a h., proposed by F.H.C.*Crick*, that an adaptor*molecule**must*be*present*between the information-containing DNA and the*protein*being synthesized.-**alternative h.**in Neyman-Pearson*testing*of a h., the h. or*family*of hypotheses about the numerical*value*of a*parameter*if and only if the null h. is rejected as untenable.-that*autocrine*h.*tumor*cells containing*viral*oncogenes may have encoded a*growth**factor*, normally produced by other*cell*types, and thereby produce the*factor*autonomously, leading to uncontrolled*proliferation*.-**Bayesian h.**an array of surmised values of a*parameter*to be severally explored in the*light*of a*current*set of*data*, with logical*symmetry*being preserved among all. The merits of each h. entertained are based on quantity, the prior*probability*. The*probability*of the*data*conditional on the h. is computed as the conditional*probability*for each; the*product*of the two for each h. is the*joint**probability*, and the*ratio*of each*joint**probability*to the sum of all the*joint*probabilities is the*posterior**probability*for that h.. Unlike the Neyman-Pearson*test*of hypotheses, the answer is a statement about the h., not about the*sample*conditional on the h.. No h. is preferred or prevails by default. The*procedure*may be applied recursively any*number*of times, as the*data*becomes available.-**frustration-**the*aggression*h.*theory*that*frustration*may*lead*to*aggression*, but that*aggression*is always the result of some*form*of*frustration*.-**Goldie-Coldman h.**a mathematic*model*that predicts that*tumor*cells mutate to a resistant*phenotype*at a*rate*dependent on their*intrinsic**genetic**instability*. The*probability*that a*cancer*would contain drug-resistant clones depends on the*mutation**rate*and the size of the*tumor*. According to this h., even the smallest detectable cancers would contain at least 1 drug-resistant*clone*; therefore, the best chance of*cure*would be to use all effective*chemotherapy*drugs; in*practice*, this has meant using 2 different non–cross-resistant*chemotherapy*regimens in alternating cycles.-a*Gompertz*h.*theory*that the*force*of*mortality*increases in geometrical progression, being based on the*assumption*that the*average**exhaustion*of an individual's*power*to avoid*death*is such that at the end of equal infinitely small intervals of*time*the individual loses equal proportions of the*power*to oppose destruction that were available at the commencement of each of these intervals.-obsolete*insular*h.*theory*of the*origin*of*diabetes*mellitus from destruction or loss of*function*of the islets of*Langerhans*in the*pancreas*.-**Knudsen h.**an explanation for the*bilateral*(and earlier) occurrence of*hereditary**retinoblastoma*; if one*tumor**suppressor**gene*is mutated by*inheritance*, only one*somatic**mutation*is needed*inactivate*the other*allele*. In the*sporadic**form*, 2 mutations, which*inactivate*each*allele*, are necessary.-SYN:*Lyon*h.*lyonization*.-a*Makeham*h.*development*of*Gompertz*h. as to the*force*of*mortality*following some mathematical law.*Makeham*assumed that*death*was the consequence of two generally coexisting causes: 1) chance; 2) a*deterioration*or increased inability to withstand destruction. The first of these is*constant*, the second is an increasing geometrical progression.-**Michaelis-**a h. that a*Menten*h.*complex*is formed between an*enzyme*and its*substrate*(also known as the O'Sullivan-Tompson h.), which*complex*then decomposes to*yield*free*enzyme*and the*reaction*products (also referred to as the*Brown*h.), the latter*step*being the rate-determining*step*for the overall*rate*of substrate-product*conversion*. SEE ALSO: Michaelis-*Menten*constant, Michaelis-*Menten*equation.-**mnemic h.**the*theory*that stimuli or irritants leave definite traces (engrams) on the*protoplasm*of the*animal*, and when these stimuli are regularly repeated they*induce*a*habit*which persists after the stimuli cease. SYN: mnemic theory,*mnemism*, Semon-*Hering*theory.-the classical*monoamine*h.*theory*of the neurochemical*basis*of*depression*linking it to a*deficiency*of at least one of three*monoamine*neurotransmitters,*norepinephrine*,*serotonin*, or*dopamine*.-**Neyman-**a formal conjecture about the numerical*Pearson*statistical h.*value*of a*parameter*to be tested exclusively in the*light*of an immediate set of*data*without attention to prior knowledge or convictions and ignoring other sets of evidence treated in a similar fashion. The answer is a statement not about whether the h. is true but whether it is an acceptable explanation of the*data*or should be rejected in favor of another h..-**Norton-Simon h.**h. that a*tumor*is composed of populations of faster-growing cells, which are*sensitive*to*therapy*, and slower-growing, more resistant cells. Since only*therapy*that completely eradicates all*tumor*cells will be*curative*, this is most likely to occur with*sequential*, non–cross-resistant regimens. The initial*regimen**must*be effective enough to result in a low*residual**tumor**burden*and is followed by one or more non–cross-resistant treatments to eradicate the remainder of the*cancer*.-**null h.**the statistical h. that one*variable*has no*association*with another*variable*or set of variables, or that two or more populations do not differ from each other; the statement that results do not differ from those that might be*expected*by the*operation*of chance alone; if rejected, it increases confidence in the h..-that the*sequence*h.*amino acid**sequence*of a*protein*is determined by a particular*sequence*of nucleotides (the*cistron*) in the DNA of the*organism*producing the*protein*.-**sliding**the*filament*h.*theory*that the contracting*muscle*shortens because two sets of filaments*slide*past each other.-the*Starling*h.*principle*that net*filtration*through*capillary*membranes is proportional to the*transmembrane**hydrostatic**pressure**difference*minus the*transmembrane**oncotic**pressure**difference*; although well established, it is called*Starling*h. to distinguish it from*Starling*law of the*heart*.-**upregulation/downregulation h.**a*theory*of the neurochemical*basis*of*depression*(an*elaboration*of the*monoamine*h.) linking it to an*increase*in*number*(upregulation) of*postsynaptic**monoamine*receptors, which are then effectively decreased in*number*(downregulation) as a result of*antidepressant**activity*. SEE ALSO:*monoamine*h..-**zwitter h.**that an*amphoteric**molecule*( e.g., an*amino acid*) has, at its*isoelectric**point*, equal numbers of*positive*and*negative*charges,*thus*becoming a zwitterion.* * *

**hy·poth·e·sis hī-'päth-ə-səs***n*,*pl***-e·ses -.sēz**a proposition tentatively assumed in order to draw out its logical or empirical consequences and test its consistency with facts that are known or may be determined*<it appears, then, to be a condition of the most genuinely scientific \hypothesis that it be...of such a nature as to be either proved or disproved by comparison with observed facts*(J. S. Mill)*>** * *

hy·poth·e·sis (hi-pothґə-sis) a supposition that appears to explain a group of phenomena and is advanced as a basis for further investigation; a proposition that is subject to proof or to an experimental or statistical test. See also*theory.*

*Medical dictionary.
2011.*

**Synonyms**:

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**hypothesis**— hypothesis, theory, law are often interchangeable in general use. In their technical senses they are usually discriminated by the scientists and philosophers who employ them. In general the terms denote an inference from data that is offered as a … New Dictionary of Synonyms**hypothesis**— hy‧poth‧e‧sis [haɪˈpɒθss ǁ ˈpɑː ] noun hypotheses PLURALFORM [ siːz] [countable] STATISTICS an idea that can be tested to see if it is true or not: • These results support the hypothesis that individuals are willing to pay more in order to live … Financial and business terms**hypothesis**— hypothesis, hypothesis testing A hypothesis is an untested statement about the relationship (usually of association or causation) between concepts within a given theory . Hypothesis testing involves the testing of a hypothesis in a scientific… … Dictionary of sociology**Hypothesis**— Hy*poth e*sis, n.; pl. {Hypotheses}. [NL., fr. Gr. ? foundation, supposition, fr. ? to place under, ? under + ? to put. See {Hypo }, {Thesis}.] 1. A supposition; a proposition or principle which is supposed or taken for granted, in order to draw… … The Collaborative International Dictionary of English**hypothesis**— I noun assertion, assignment of cause, assumption, conclusion drawn from accepted truths, coniectura, conjecture, deduction, guess, inference, postulate, postulation, speculation, suggestion, supposal, supposition, surmise, tentative explanation … Law dictionary**hypothesis**— 1590s, from M.Fr. hypothese and directly from L.L. hypothesis, from Gk. hypothesis base, basis of an argument, supposition, lit. a placing under, from hypo under (see SUB (Cf. sub )) + thesis a placing, proposition (see THESIS (Cf. thesis)) … Etymology dictionary**hypothesis**— [hī päth′ə sis, hipäth′ə sis] n. pl. hypotheses [hī päth′əsēz΄, hi päth′əsēz΄] [Gr, groundwork, foundation, supposition < hypotithenai, to place under < hypo , under + tithenai, to place: see HYPO & DO1] an unproved theory, proposition,… … English World dictionary**hypothesis**— hypothesis. См. теория попаданий. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.**hypothesis**— hypothesis. См. теория онкогенов. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.**hypothesis**— meaning ‘something proposed as a basis for reasoning’, has the plural form hypotheses, pronounced seez … Modern English usage**hypothesis**— [n] theory antecedent, apriority, assignment, assumption, attribution, axiom, basis, belief, conclusion, condition, conjecture, data, deduction, demonstration, derivation, explanation, foundation, ground, guess, inference, interpretation, layout … New thesaurus