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101.
Many conditions interfere with butyrylcholinesterase (BChE) activity, e.g., pregnancy or presence of the BCHE gene variant −116A can decrease activity whereas obesity and types I and II diabetes mellitus can increase activity. In this study, we examined BChE activity, −116A and 1615A BCHE gene variants, and anthropometric and biochemical variables associated with diabetes in patients with gestational diabetes mellitus (GDM) and in healthy pregnant women. BChE activity was measured spectrophotometrically using propionylthiocholine as substrate and genotyping of the −116 and 1615 sites of the BCHE gene was done with a TaqMan SNP genotyping assay. Three groups were studied: 150 patients with GDM, 295 healthy pregnant women and 156 non-pregnant healthy women. Mean BChE activity was significantly lower in healthy pregnant women than in women from the general population and was further reduced in GDM patients. BChE activity was significantly reduced in carriers of −116A in GDM patients and healthy pregnant women. Although GDM patients had a significantly higher mean body mass index (BMI) and triglycerides than healthy pregnant women, they had lower mean BChE activity, suggesting that the lowering effect of GDM on BChE activity was stronger than the characteristic enhancing effect of increased BMI and triglycerides.  相似文献   
102.
Testicular germ cell tumors (TGCT) represent the most common malignancy among young males. To our knowledge no comprehensive Copy Number Variation (CNVs) studies of TGCT using high-resolution Single Nucleotide Polymorphism (SNP) array have been performed. By a genome-wide analysis of CNV and loss of heterozygosity (LOH) in 25 primary seminomas, we confirmed several previously reported genomic alterations and discovered eight novel genomic alterations including amplifications and homozygous deletions. Moreover, a comparison of genomic alterations of early and late stage seminoma identified CNVs that correlate with progression, which included deletions in chromosomes 4q, 5p, 9q, 13q and 20p and amplifications in chromosomes 9q and 13q. We compared previously perform Affymetrix expression analysis in a subset of samples and found robust correlation between expression and genomic alterations. Furthermore, high correlations (40-75%) were observed between CNV by SNP analysis and quantitative PCR. Our findings may lead to better understanding of TGTC's pathogenesis.  相似文献   
103.
Fidelity of individual animals to breeding sites is a primary determinant of population structure. The degree and scale of philopatry in a population reflect the fitness effects of social facilitation, ecological adaptation and optimal inbreeding. Patterns of breeding-site movement and fidelity are functions of social structure and are frequently sex biased. We report on a female humpback whale (Megaptera novaeangliae) first identified by natural markings off Brazil that subsequently was photographed off Madagascar. The minimum travel distance between these locations is greater than 9800 km, approximately 4000 km longer than any previously reported movement between breeding grounds, more than twice the species' typical seasonal migratory distance and the longest documented movement by a mammal. It is unexpected to find this exceptional long-distance movement between breeding groups by a female, as models of philopatry suggest that male mammals move more frequently or over longer distances in search of mating opportunities. While such movement may be advantageous, especially in changeable or unpredictable circumstances, it is not possible to unambiguously ascribe causality to this rare observation. This finding illustrates the behavioural flexibility in movement patterns that may be demonstrated within a typically philopatric species.  相似文献   
104.
105.
This study was conducted to evaluate the impact of a food aid program (Plan Más Vida, PMV) on the micronutrient nutritional condition of lactating mothers 1?year after its implementation. The food program provided supplementary diets (wheat- and maize-fortified flour, rice or sugar, and fortified soup) to low-income families from the province of Buenos Aires, Argentina. A prospective, non-experimental study was carried out to evaluate the micronutrient nutritional status of lactating mothers (n?=?178 at baseline and n?=?151 after 1?year). Biochemical tests (hemoglobin, ferritin, zinc, vitamin A, and folic acid), anthropometric assessments (weight and height) and dietary surveys (24-h recall) were performed. We found no significant changes in anthropometric values 1?year after the intervention. The risk for vitamin A (retinol 20?C30???g/dl) and folate deficiency significantly decreased 1?year after PMV implementation (56.3 vs. 29.9 and 50.3 vs. 3.4?%, respectively; p?<?0.001). Anemia was seen in 25.8?% of lactating mothers at baseline, without statistically significant differences 1?year after (p?=?0.439). The nutritional data obtained after assessing the early impact of PMV actions may be useful to provincial health authorities to perform periodic evaluations in the future.  相似文献   
106.
In Mycobacterium tuberculosis (MTB) infection, the complex interaction of host immune system and the mycobacteria is associated with levels of cytokines production that play a major role in determining the outcome of the disease. Several single-nucleotide polymorphisms (SNPs) in cytokine genes have been associated with tuberculosis (TB) outcome. The aim of this study was to evaluate the association between previously reported SNPs IL2–330 T>G (rs2069762); IL4–590 C>T (rs2243250); IL6–174 G>C (rs1800795); IL10–592 A>C (rs1800872); IL10–1082 G>A (rs1800896); IL17A -692 C>T (rs8193036); IL17A -197 G>A (rs2275913); TNF -238 G>A (rs361525); TNF -308 G>A (rs1800629) and IFNG +874 T>A (rs2430561) and pulmonary TB (PTB) susceptibility. We conducted a case-control study in individuals from Southern Brazil who were recruited between February 2012 and October 2013 in a high incidence TB city. We performed a multiplex genotyping assay in 191 patients with PTB and 175 healthy subjects. Our results suggest a decreased risk for PTB development associated with the IL17A -197A allele (OR = 0.29; p = 0.04), AA genotype (OR = 0.12; p = 0.04) and A carrier (AG/AA) (OR = 0.29; p = 0.004) and IL6 -174C carrier (CC/CG) (OR = 0.46; p = 0.04). We could not properly analyze IL17A -692 C>T (rs8193036) and IFNG +874T>A due to genotypic inconsistencies and found no evidence of association for the IL2, IL4, IL10 and TNF polymorphisms and PTB. In conclusion, our results show a protective effect of IL17 and IL6 polymorphisms on PTB outcome in Southern Brazilian population.  相似文献   
107.
This work shows, for the first time, a properly metabolically regulated squid nerve Na+/Ca2+ exchanger (NCXSQ1) heterologous expressed in Saccharomyces cerevisiae. The exchanger was fused to the enhanced green fluorescence protein (eGFP) on its C-terminus and had two tags, a Strep-tag II and 6 histidines, added to the N-terminal region (ST–6HB–NCXSQ1–eGFP). The eGFP fluorescence signal co-localized with that of the plasma membrane marker FM1-43 in whole cells that displayed an uptake of Ca2+ with the expected characteristics of the reverse Na+/Ca2+ exchange mode. Similar to squid nerve membrane vesicles, inside-out yeast plasma membrane vesicles (ISOV) showed a Ca2+i regulation of the forward mode that was modulated by previously phosphorylated regulatory cytosolic protein (ReP1–NCXSQ). On the other hand, a close association between NCXSQ1 and ReP1–NCXSQ, estimated by co-immunoprecipitation, was independent of ReP1–NCXSQ phosphorylation. An additional crucial observation was that in proteoliposomes containing only the ST–6HB–NCXSQ1–eGFP protein, Na+/Ca2+ exchange was stimulated by phosphorylated ReP1–NCXSQ; i.e., this up-regulation needs no other requirement besides the lipid membrane and the exchanger protein. Finally, this work provides a potential approach to obtain enough purified NCXSQ1 for structural and biochemical studies which have been delayed due to the lack of sufficient material.  相似文献   
108.
Alouatta guariba clamitans (brown howler monkey) is an endemic primate from the southeastern Brazil tropical forests, classified as near threatened by the IUCN Red List 2007. The genus Alouatta is one of the most difficult New World monkeys to breed and rear in captivity. In this study we examined the macroscopic and histological aspects of the female genital tract of wild brown howler monkeys to provide baseline information for future reproduction research. The anatomical relationship between the vagina, uterus, broad ligament, oviducts and ovaries are those of a typical primate reproductive tract. The fundic portion of the uterus is globoid, the cervix is well developed, which confers to the uterus an elongated shape, and the vagina is a long flattened channel. Histological analysis conducted in females in the follicular phase revealed large quantities of interstitial luteinized tissue in the ovaries, a stratified nonkeratinized vaginal epithelium, lack of glands in the vaginal mucosa and simple tubular endometrial glands. The observed anatomical features should be considered in the adaptation and application of assisted reproductive techniques aimed at improving captive reproduction for species conservation. Am. J. Primatol. 71:145–152, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
109.
A biometrical analysis of the dinoflagellate cyst Lingulodinium machaerophorum [Deflandre, G., Cookson, I.C., 1955. Fossil microplankton from Australia late Mesozoic and Tertiary sediments. Australian journal of Marine and Freshwater Research 6: 242–313.] Wall, 1967 in 144 globally distributed surface sediment samples revealed that the average process length is related to summer salinity and temperature at a water depth of 30 m by the equation (salinity/temperature) = (0.078?average process length + 0.534) with R2 = 0.69. This relationship can be used to reconstruct palaeosalinities, albeit with caution. The particular ecological window can be associated with known distributions of the corresponding motile stage Lingulodinium polyedrum (Stein) Dodge, 1989. Confocal laser microscopy showed that the average process length is positively related to the average distance between process bases (R2 = 0.78), and negatively related to the number of processes (R2 = 0.65). These results document the existence of two end members in cyst formation: one with many short, densely distributed processes and one with a few, long, widely spaced processes, which can be respectively related to low and high salinity/temperature ratios. Obstruction during formation of the cysts causes anomalous distributions of the processes. From a biological perspective, processes function to facilitate sinking of the cysts through clustering.  相似文献   
110.
l -Cysteine and methionine are unique amino acids that act as sulfur donors in all organisms. In the specific case of Trypanosomatids, l -cysteine is particularly relevant as a substrate in the synthesis of trypanothione. Although it can be synthesized de novo , l -cysteine is actively transported in Trypanosoma cruzi epimastigote cells. l -Cysteine uptake is highly specific; none of the amino acids assayed yield significant differences in terms of transport rates. l -Cysteine is transported by epimastigote cells with a calculated apparent K m of 49.5 μM and a V max of about 13 pmol min−1 per 107 cells. This transport is finely regulated by amino acid starvation, extracellular pH, and between the parasite growth phases. In addition, l -cysteine is incorporated post-translationally into proteins, suggesting its role in iron–sulfur core formation. Finally, the metabolic fates of l -cysteine were predicted in silico .  相似文献   
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