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161.
In the present study, we examined the ability of immature germinal vesicle (GV) and subjected to in vitro matured (MII) yak oocytes to survive after cryopreservation as well as their subsequent development following in vitro maturation and fertilization. Both GV and MII oocytes were cryopreserved by using two different vitrification solutions (VS); VS-I contained 10% ethylene glycol (EG) and 10% dimethylsulfoxide (DMSO) in TCM-199 + 20% (v/v) fetal calf serum (FCS) whereas VS-II contained 40% EG + 18% Ficoll + 0.5 M sucrose in TCM-199 + 20% FCS. The percentage of oocytes found to be morphologically normal was greater (P < 0.01) in VS-I group than in VS-II group. Rates of cleavage (30.6–42.2%) and blastocyst formation (2.9–8.9%) did not differ among groups, but were lower than in unfrozen control (55.7% and 25.4%, P < 0.01). These results show that a combination of EG and DMSO or EG, Ficoll and sucrose can be used to cryopreserve yak oocytes in French straws.  相似文献   
162.
Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70 kDa heat shock protein (hsp70) and 60 kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois’ leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis.  相似文献   
163.
The chemical uncoupler 2,4-dinitrophenol (DNP) was an effective and widely used weight loss drug in the early 1930s. However, the physiology of DNP has not been studied in detail because toxicity, including hyperthermia and death, reduced interest in the clinical use of chemical uncouplers. To investigate DNP action, mice fed a high fat diet and housed at 30 °C (to minimize facultative thermogenesis) were treated with 800 mg/liter DNP in drinking water. DNP treatment increased energy expenditure by ∼17%, but did not change food intake. DNP-treated mice weighed 26% less than controls after 2 months of treatment due to decreased fat mass, without a change in lean mass. DNP improved glucose tolerance and reduced hepatic steatosis without observed toxicity. DNP treatment also reduced circulating T3 and T4 levels, Ucp1 expression, and brown adipose tissue activity, demonstrating that DNP-mediated heat generation substituted for brown adipose tissue thermogenesis. At 22 °C, a typical vivarium temperature that is below thermoneutrality, DNP treatment had no effect on body weight, adiposity, or glucose homeostasis. Thus, environmental temperature should be considered when assessing an anti-obesity drug in mice, particularly agents acting on energy expenditure. Furthermore, the beneficial effects of DNP suggest that chemical uncouplers deserve further investigation for the treatment of obesity and its comorbidities.  相似文献   
164.
Anoxybacillus flavithermus subsp. yunnanensis is the only strictly thermophilic bacterium that is able to tolerate a broad range of toxic solvents at its optimal temperature of 55-60°C. The type strain E13T was isolated from water-sediment slurries collected from a hot spring. This study presents the draft genome sequence of A. flavithermus subsp. yunnanensis E13T and its annotation. The 2,838,393bp long genome (67 contigs) contains 3,035 protein-coding genes and 85 RNA genes, including 10 rRNA genes, and no plasmids. The genome information has been used to compare with the genomes from A. flavithermus subsp. flavithermus strains.  相似文献   
165.
近年广西银杏病虫害发生及防治对策   总被引:4,自引:0,他引:4  
梁惠凌  唐辉  韦霄  李锋   《广西植物》2000,20(3):264-268
近年来 ,银杏病虫害在广西各栽培地区普遍发生。主要报导了在广西危害比较严重 ,造成较大经济损失的病虫害及其危害症状、形态特征、发生规律和防治措施。这些病虫害在广西多属首次发现报导。  相似文献   
166.

Objective

To investigate the roles of miR-145 in lung adenocarcinoma (LAC) and to clarify the regulation of N-cadherin by miR-145.

Results

In 57 paired clinical LAC tissues, diminished miR-145 was significantly correlated with the lymph node metastasis and was negatively correlated with N-cadherin mRNA level expression. Wound healing and transwell assays revealed a reduced capability of tumor metastasis induced by miR-145 in LAC. miR-145 negatively regulated the invasion of cell lines through targeting N-cadherin by directly binding to its 3′-untranslated region. Silencing of N-cadherin inhibited invasion and migration of LAC cell lines similar to miR-145 overexpression.

Conclusions

MiR-145 could inhibit invasion and migration of lung adenocarcinoma cell lines by directly targeting N-cadherin.
  相似文献   
167.
S,N co‐doped carbon quantum dots (N,S‐CQDs) with super high quantum yield (79%) were prepared by the hydrothermal method and characterized by transmission electron microscopy, photoluminescence, UV–Vis spectroscopy and Fourier transformed infrared spectroscopy. N,S‐CQDs can enhance the chemiluminescence intensity of a luminol–H2O2 system. The possible mechanism of the luminol–H2O2–(N,S‐CQDs) was illustrated by using chemiluminescence, photoluminescence and ultraviolet analysis. Ranitidine can quench the chemiluminescence intensity of a luminol–H2O2–N,S‐CQDs system. So, a novel flow‐injection chemiluminescence method was designed to determine ranitidine within a linear range of 0.5–50 μg ml?1 and a detection limit of 0.12 μg ml?1. The method shows promising application prospects.  相似文献   
168.
The oral microbiota influences health and disease states. Some gram‐negative anaerobic bacteria play important roles in tissue destruction associated with periodontal disease. Lactoferrin (LF) and lactoperoxidase (LPO) are antimicrobial proteins found in saliva; however, their influence on the whole oral microbiota currently remains unknown. In this randomized, double‐blinded, placebo‐controlled study, the effects of long‐term ingestion of LF and LPO‐containing tablets on the microbiota of supragingival plaque and tongue coating were assessed. Forty‐six older individuals ingested placebo or test tablets after every meal for 8 weeks. The relative abundance of bacterial species was assessed by 16S rRNA gene high‐throughput sequencing. Most of the bacterial species in supragingival plaque and tongue coating that exhibited significant decreases in the test group were gram‐negative bacteria, including periodontal pathogens. Decreases in the total relative abundance of gram‐negative organisms in supragingival plaque and tongue coating correlated with improvements in assessed variables related to oral health, such as oral malodor and plaque accumulation. Furthermore, there was significantly less microbiota diversity in supragingival plaque at 8 weeks in the test group than in the placebo group and low microbiota diversity correlated with improvements in assessed variables related to oral health. These results suggest that LF and LPO‐containing tablets promote a shift from a highly diverse and gram‐negative‐dominated to a gram‐positive‐dominated community in the microbiota of supragingival plaque and tongue coating. This microbial shift may contribute to improvements in oral health, including oral malodor and state of the gingiva.
  相似文献   
169.
170.

Objective

Recent studies suggested that secreted protein acidic and rich in cysteine (SPARC), a novel adipokine, is a key player in the pathology of obesity and type 2 diabetes. We aimed to determine whether concentrations of SPARC were altered in patients with gestational diabetes mellitus (GDM) compared to normal glucose tolerance (NGT) controls and to investigate the relationships between SPARC and metabolic parameters in pregnant women.

Design/Methods

Cross-sectional study of 120 pregnant women with GDM and 60 controls with NGT, in a university hospital setting. Plasma levels of SPARC, adiponectin, fibroblast growth factor 21 (FGF21), insulin and proinsulin were determined by ELISA.

Results

GDM women had higher SPARC and lower adiponectin than NGT subjects; no difference was found in FGF21. SPARC levels were the lowest in subjects in the third tertile of insulin sensitivity index (ISIOGTT) and correlated positively with pre-pregnant BMI, insulin and 3 h glucose during 100-g OGTT, HOMA-IR, fasting proinsulin, hsCRP and white blood cells count, and negatively with ISIOGTT, when adjusting for gestational age. Triglyceride (TG), Apolipoprotein A1, apolipoprotein B and lipoprotein (a) correlated with SPARC in partial Pearson correlation. Correlations between SPARC with adiponectin, systolic blood pressure and TG were marginally significant in partial Spearman correlation analysis. In multivariate regression analysis, SPARC was an independent negative indicator of ISIOGTT.

Conclusions

SPARC levels are correlated significantly with inflammation and may also be correlated with dyslipidemia and represent an independent determinant of insulin resistance in late pregnancy, indicating a potential role of SPARC in the pathophysiology of GDM.  相似文献   
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