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1.
Analyses of ITS sequences for 49 species of Olearia, including representatives from all currently recognised intergeneric sections, and 43 species from 23 other genera of Astereae,
rooted on eight sequences from Anthemideae, provide no support for the monophyly of this large and morphologically diverse
Australasian genus. Eighteen separate lineages of Olearia are recognised, including seven robust groups. Three of these groups and another eight species are placed within a primary
clade incorporating representatives of Achnophora, Aster, Brachyscome, Calotis, Camptacra, Erigeron, Felicia, Grangea, Kippistia, Lagenifera, Minuria, Oritrophium,
Peripleura, Podocoma, Remya, Solidago, Tetramolopium and Vittadinia. The remaining four groups and three individual species lie within a sister clade that also includes Celmisia, Chiliotrichum, Damnamenia, Pleurophyllum and Pachystegia. Relationships within each primary clade are poorly resolved. There is some congruence between this molecular estimate of
the phylogeny and the distribution of types of abaxial leaf-hair, which is the basis of the present sectional classification
of Olearia, but all states appear to have arisen more than once within the tribe. It is concluded that those species placed within the
second primary clade should be removed from the genus, but the extent to which species placed within the first primary clade
constitute a monophyletic group can only be resolved with further sequence data.
Received November 12, 2001; accepted April 29, 2002 Published online: November 22, 2002
Addresses of authors: Edward W. Cross, Centre for Plant Biodiversity Research, CSIRO, GPO Box 1600, Canberra, ACT 2601, Australia
(E-mail: ed.cross@csiro.au); Christopher J . Quinn, Royal Botanic Gardens, Mrs Macquaries Rd., Sydney, NSW 2000, Australia;
Steven J. Wagstaff, Landcare Research, PO Box 69, Lincoln 8152, New Zealand. 相似文献
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Familial Angelman syndrome (AS) can result from mutations in chromosome 15q11q13 that, when transmitted from father to child, result in no phenotypic abnormality but, when transmitted from mother to child, cause AS. These mutations therefore behave neither as dominant nor as recessive mutations but, rather, show an imprinted mode of inheritance. We have analyzed two sibling pairs with AS and a larger family with four AS offspring of three sisters with several recently described microsatellite polymorphisms in the AS region. AS siblings inherited the same maternal alleles at the GABRB3 and GABRA5 loci, and the unaffected siblings of AS individuals inherited the other maternal alleles at these loci. In one of the AS sibling pairs, analysis of a recombination event indicates that the mutation responsible for AS is distal to locus D15S63. This result is consistent with a previously described imprinted submicroscopic deletion causing AS, a deletion that includes loci D15S10, D15S113, and GABRB3, all distal to D15S63. The analysis of the larger AS family provides the first clear demonstration of a new mutation in nondeletion AS. Analysis of linkage of AS to GABRB3 in these three families, on the assumption of imprinted inheritance (i.e., penetrance of an AS mutation is 1 if transmitted maternally and is 0 if transmitted paternally), indicates a maximum lod score of 3.52 at theta = 0. 相似文献
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A. Gough S. Chapman K. Wagstaff P. Emery E. Elias 《BMJ (Clinical research ed.)》1996,312(7024):169-172
Monocycline is the most widely prescribed systemic antibiotic for acne largely because it needs to be given only once or twice a day and seems not to induce resistance. Up to April 1994 11 cases of minocycline induced systemic lupus erythematosus and 16 cases of hepatitis had been reported to the Committee on Safety of Medicines. An analysis of these cases together with seven other cases shows the severity of some of these reactions. Two patients died while taking the drug for acne and a further patient needed a liver transplant. Acne itself can induce arthritis and is often seen in association with autoimmine liver disease, but the clinical and biochemical resolution seen after withdrawal of the drug, despite deterioration of the acne, suggests a drug reaction. In five cases re-exposure led to recurrence. Because reactions may be severe early recognition is important to aid recovery and also to avoid invasive investigations and treatments such as corticosteroids and immunosuppresants. Safer alternatives should be considered for treating acne. 相似文献
5.
大鼠胼胝体内神经肽Y免疫反应阳性纤维的发育 总被引:1,自引:0,他引:1
本实验用免疫组织化学ABC法研究了大鼠胼胝体内神经肽Y免疫反应阳性(NPY-IR)纤维的生后发育。结果发现,许多NPY-IR纤维在大鼠出生时便存在于胼胝体内。NPY-IR胼胝体纤维的密度在生后1周内继续逐渐增高,在第2周内达到最高峰。之后,NPY-IR胼胝体纤维的密度逐渐下降,至第3周末时接近成年时的水平,即仅有少量NPY-IR纤维存在于胼胝体内。这些结果提示在大鼠早期生后发育过程中许多NPY-IR胼胝体纤维是暂时性的,其作用可能与大脑皮质的机能发育有关。 相似文献
6.
Chemical reaction of coenzyme M, sodium 2-mercaptoethanesulphonate (HS-CoM, Na+), and formaldehyde formed sodium 2-(hydroxymethylthio)ethanesulphonate (HOCH2-S-CoM), whereas reaction with the ammonium salt of HS-CoM yielded iminobis-[2-(methylthio)ethanesulphonate], monoammonium salt [NH = (CH2 - S - CoM)2]. In water, NH = (CH2 - S - CoM)2 decomposed to 2-(aminomethylthio)ethanesulphonate (NH2CH2 - S - CoM) and HOCH2-S-CoM. NH-2-CH2 - CoM was degraded further to form more HOCH2-S-CoM. The structures of these coenzyme M derivatives were confirmed by i.r. and n.m.r. spectroscopy and by elemental analysis. When added to cell extracts of Methanobacterium thermoautotrophicum, methane was formed from either HOCH2 - S - CoM or NH = (CH2 - S - CoM)2 at rates comparable with the rate of methane formation from the methanogenic precursor 2-(methylthio)-ethanesulphonate (CH3 - S - CoM). Formaldehyde was reduced to methane at similar rates. In addition, certain hemimercaptals, including thiazolidine and thiazolidine-4-carboxylate, were reduced, although at slower rates. The reduction of formaldehyde, thiazolidine, or thiazolidine-4-carboxylate required catalytic amounts of HS-CoM. ATP was required by cells extracts for reduction of each of these methane precursors. 相似文献
7.
Peptide YY (PYY) and ghrelin (GHR) may modulate one another's actions within the hypothalamus. Peripheral infusion of PYY in humans acutely suppresses circulating concentrations of GHR. Whether an association between PYY and GHR exists in the peripheral circulation of humans over 24 h is unknown. The purpose of this study was to determine if circulating concentrations of PYY and GHR were significantly associated over 24 h in humans. Participants (n = 13) were normal weight, moderately active, women ages 18–24 yr. Blood samples were obtained q10 min for 24 h and assayed using RIA for total PYY and total GHR hourly from 0800 to 1000 h and 2000 to 0800 h and q20 min from 1000 to 2000 h. Dietary intake during the 24 h procedure was comprised of 55% carbohydrates, 30% fat, and 15% protein (three meals and a snack). Statistical analyses included linear mixed-effects modeling to test whether PYY predicted GHR concentrations over 24 h. Participants weighed 57.0 ± 1.5 kg and had 26.1 ± 1.5% body fat (15.0 ± 1.1 kg), 42.1 ± 1.1 kg fat free mass, a BMI of 21.3 ± 0.5 kg/m2 and RMR of 1072 ± 28 kcal/24 h. Visually, PYY and GHR exhibited an inverse association over nearly the entire 24 h period. Statistically, circulating concentrations of 24 h PYY predicted 24 h GHR (ghrelin = 1860.51–2.14*PYY; p = 0.04). Circulating concentrations of PYY are inversely associated with GHR over 24 h. These data provide evidence that PYY may contribute to the modulation of the secretion of GHR in normal weight, premenopausal women over a 24 h period and supports similar inferences from experimental studies in animals and humans. 相似文献
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