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811.
812.
813.
Recent genome-wide association studies identified genetic variants that confer susceptibility to type 2 diabetes mellitus (T2DM). However, few longitudinal genome-wide association studies of this metabolic disorder have been reported to date. Therefore, we performed a longitudinal exome-wide association study of T2DM, using 24,579 single nucleotide polymorphisms (SNPs) and repeated measurements from 6022 Japanese individuals. The generalized estimating equation model was applied to test relations of SNPs to three T2DM-related parameters: prevalence of T2DM, fasting plasma glucose level, and blood glycosylated hemoglobin content. Three SNPs that passed quality control were significantly (P < 2.26 × 10? 7) associated with two of the three T2DM-related parameters in additive and recessive models. Of the three SNPs, rs6414624 in EVC and rs78338345 in GGA3 were novel susceptibility loci for T2DM. In the present study, the SNP of GGA3 was predicted to be a genetic variant whose minor allele frequency has recently increased in East Asia.  相似文献   
814.
A novel chiral derivatization reagent, the N‐[1‐oxo‐5‐(triphenylphosphonium)pentyl]‐ (R)‐1,3‐thiazolidinyl‐4‐N‐hydroxysuccinimide ester bromide salt (OTPTHE), was developed for the separation and selective detection of chiral DL‐amino acids by RP‐HPLC analysis. The OTPTHE reacted with DL‐amino acids at 60°C maintained for 30 minutes in the presence of 100 mM borate buffer (pH 9.5). The separability of the diastereomeric derivatives was evaluated in terms of the resolution value (Rs) using 13 kinds of DL‐amino acids, which were completely separated by reversed‐phase chromatography using C18 column at 254 nm. The Rs of the DL‐amino acids varied from 1.62 to 2.51. As for the application of the DL‐amino acids, the determination of DL‐Ser in the human plasma of healthy volunteers was performed based on our developed method. It was shown that linear calibrations were available with high coefficients of correlation (r2 > 0.9997). The limit of detection (S/N = 3) of the DL‐Ser enantiomers was 5.0 pmol; the relative standard deviations of the intraday and interday variations were below 4.56%; the accuracy ranged between 95.40%‐110.06% and 95.45%‐109.80%, respectively; the mean recoveries (%) of the DL‐Ser spiked in the human plasma were 99.49%‐103.74%. The amounts of DL‐Ser in the human plasma of healthy volunteers were determined.  相似文献   
815.
The universal role of calcium (Ca2+) as a second messenger in cells depends on a large number of Ca2+‐binding proteins (CBP), which are able to bind Ca2+ through specific domains. Many CBPs share a type of Ca2+‐binding domain known as the EF‐hand. The EF‐hand motif has been well studied and consists of a helix‐loop‐helix structural domain with specific amino acids in the loop region that interact with Ca2+. In Toxoplasma gondii a large number of genes (approximately 68) are predicted to have at least one EF‐hand motif. The majority of these genes have not been characterized. We report the characterization of two EF‐hand motif‐containing proteins, TgGT1_216620 and TgGT1_280480, which localize to the plasma membrane and to the rhoptry bulb, respectively. Genetic disruption of these genes by CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR‐associated protein 9) resulted in mutant parasite clones (Δtg216620 and Δtg280480) that grew at a slower rate than control cells. Ca2+ measurements showed that Δtg216620 cells did not respond to extracellular Ca2+ as the parental controls while Δtg280480 cells appeared to respond as the parental cells. Our hypothesis is that TgGT1_216620 is important for Ca2+ influx while TgGT1_280480 may be playing a different role in the rhoptries.  相似文献   
816.
Murine models and association studies in eating disorder (ED) patients have shown a role for the brain-derived neurotrophic factor (BDNF) in eating behavior. Some studies have shown association of BDNF -270C/T single-nucleotide polymorphism (SNP) with bulimia nervosa (BN), while BDNF Val66Met variant has been shown to be associated with both BN and anorexia nervosa (AN). To further test the role of this neurotrophin in humans, we screened 36 SNPs in the BDNF gene and tested for their association with ED and plasma BDNF levels as a quantitative trait. We performed a family-based association study in 106 ED nuclear families and analyzed BDNF blood levels in 110 ED patients and in 50 sib pairs discordant for ED. The rs7124442T/rs11030102C/rs11030119G haplotype was found associated with high BDNF levels (mean BDNF TCG haplotype carriers = 43.6 ng/ml vs. mean others 23.0 ng/ml, P = 0.016) and BN (Z = 2.64; P recessive = 0.008), and the rs7934165A/270T haplotype was associated with AN (Z =-2.64; P additive = 0.008). The comparison of BDNF levels in 50 ED discordant sib pairs showed elevated plasma BDNF levels for the ED group (mean controls = 41.0 vs. mean ED = 52.7; P = 0.004). Our data strongly suggest that altered BDNF levels modulated by BDNF gene variability are associated with the susceptibility to ED, providing physiological evidence that BDNF plays a role in the development of AN and BN, and strongly arguing for its involvement in eating behavior and body weight regulation.  相似文献   
817.
The large abundance of free-ranging wild boars (Sus scrofa) and a trend towards animal friendly outdoor management of domestic pigs lead to an increasing probability of disease transmission between those animal populations. In 2001, an active monitoring was started for classical swine fever (CSF), Aujeszky’s disease (AD) and porcine brucellosis (PB) in wild boars in Switzerland. The objective of this programme was to document the serological status of wild boars regarding the selected pathogens. To continue this serosurveillance, 1,060 wild boar samples were collected during two regular hunting seasons in 2004–2005. Furthermore, in a pilot study, 61 outdoor pigs from 14 farms located in areas with high wild boar densities were sampled in 2004 and serologically tested for AD and PB. All wild boar samples were negative for CSF. Seroprevalence for AD was 2.83% (95% CI 1.91–4.02%). Seroprevalence for PB was 13.5% (95% CI 10.7–16.7%) for the Rose Bengal test and 11.05% (95% CI 8.82–13.61%) for the indirect ELISA. There was no serological evidence for AD in domestic pigs. All tested animals from 13 piggeries were seronegative for PB, but three pigs from the same farm showed doubtful results. Further investigations on the farm did not indicate the presence of PB in the herd. These findings urge the need for better diagnostic tools to obtain reliable results concerning PB prevalence. Since contact and following transmission of infectious agents between infected wild boars and outdoor pigs might occur in the future, it is advisable to include outdoor pigs in areas at risk in routine surveillance programmes.  相似文献   
818.
Boar taint is a major meat-quality defect in pigs and is due to excessive accumulation of skatole and androstenone in adipose tissue. The present work investigated the relationship between carcass weight, levels of skatole and androstenone in adipose tissue, and expression of the hepatic androstenone-metabolising enzyme 3β-hydroxysteroid dehydrogenase (3β-HSD), in 22 entire male and 22 entire female crossbred pigs (Large White (40%) × Landrace (40%) × Duroc (20%)). Animals of each gender were divided into two subgroups (11 pigs in each subgroup): (i) conventional weight (carcass weight 59 to 77 kg) and (ii) heavy weight (carcass weight 84 to 95 kg). No relationship between carcass weight and adipose tissue skatole level was found for entire male pigs (r2 = 0.013, P > 0.05). There was a significant negative relationship between carcass weight and expression of the hepatic 3β-HSD protein (r2 = 0.502, P < 0.001) and a significant negative relationship between 3β-HSD protein expression and androstenone level in adipose tissue (r2 = 0.24, P < 0.05) in entire males. No relationship was found between carcass weight and 3β-HSD protein expression in female pigs (r2 = 0.001, P > 0.05). 3β-HSD expression was 59% higher in conventional-weight male pigs when compared with heavy-weight animals (P < 0.05) and 36% higher in heavy-weight females when compared with heavy-weight males (P < 0.05). It is concluded that an increase in slaughter weight of entire commercial crossbred Large White pigs is accompanied by inhibition of expression of the hepatic 3β-HSD protein, which might result in a reduced rate of hepatic androstenone clearance with its subsequent accumulation in adipose tissue. It is suggested that regulation of pig hepatic 3β-HSD expression is under the control of sex hormones.  相似文献   
819.
Pentazocine (PZ) in rat hair and plasma was determined by HPLC-fluorescence detection with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) as a labelling reagent and cyclazocine (CZ) as an internal standard (IS). PZ and IS extracted from hair or plasma sample were derivatized with DIB-Cl and the resulted solution was cleaned up with solid phase extraction. The isocratic separation of DIB-PZ and -CZ within 20 min could be achieved by a Wakopak Handy-ODS column (250 x 4.6 mm i.d.) using a mobile phase composed of 0.1 mol/L acetate buffer (pH 6.2):acetonitrile (25:75, v/v). The detection limits of PZ at a signal-to-noise ratio of 3 for rat hair and plasma were 0.18 ng/mg and 0.57 ng/mL, respectively. Reproducible and precise results could be obtained by an IS method with RSD values less than 6.6% for within- and between-day measurements. The method was successfully applied for the monitoring of PZ levels in Zucker rat hair and plasma samples after a single administration of 25 mg/kg PZ. Moreover, incorporation rates of PZ into black and white hair of Zucker rat were evaluated.  相似文献   
820.
AIMS: To investigate the microbial inactivation efficiency of a newly developed cascaded dielectric barrier discharge (CDBD) set-up against various micro-organisms on polyethylene terephthalate (PET) foils. METHODS AND RESULTS: Inactivation kinetics in dependency of time were produced with air as process gas and test strains like Salmonella serotype Mons, Staphylococcus aureus and Escherichia coli and spores of Bacillus atrophaeus, Aspergillus niger and Clostridium botulinum, which were homogeneously distributed on the sample surface by a spray method. Highest count reduction was observed for the vegetative cells with at least 6.6 log(10) within 1 s. Aspergillus niger was the most resistant test strain with an inactivation rate of about 5 log(10) in 5 s. CONCLUSIONS: For industrial applications it is necessary to evaluate new sterilization methods against a broad range of different micro-organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: CDBD plasma is a fast and effective technology for decontamination of heat sensitive materials in few seconds.  相似文献   
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