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321.
Exercises are commonly recommended for chronic neck pain, but evidence-based guidelines do not explain what types of exercise. The aim of this randomized study was to evaluate the rate of change in neck strength following high- and low-intensity neck muscle training and their effects on pain and disability. One hundred eighty women with chronic neck pain were randomized into a high-intensity strength training group (STG), local muscle endurance training group (ETG), or control group (CG). The neck training consisted of isometric exercises in the STG and dynamic exercises in the ETG. Both groups performed dynamic exercises for the upper extremities. Strength tests, neck pain, and disability indices were evaluated at the baseline, at the follow-ups after 2 and 6 months in the training groups, and after 12 months in all groups. In both groups the greatest gains in neck strength, as well as decrease in neck pain and disability, were achieved during the first 2 months. However, the improvements continued up to 12 months. The STG achieved the greatest strength gains at all follow-ups. The CG showed only minor changes, and significant differences were found in favor of the training groups in all measures. The change in neck pain and disability indices correlated with the isometric neck strength (r = -0.22 [-0.36 to - 0.08] to -0.36 [-0.49 to -0.23]). Neck and shoulder muscle training was shown to be an effective therapy for chronic neck pain, resulting in early improvement in both the strength tests and subjective measures. The results can be maintained and even improved with long-term training.  相似文献   
322.
Elevated plasma concentration of C-reactive protein has emerged as an important predictor of future cardiovascular diseases and metabolic abnormalities in apparently healthy individuals. Obese individuals tend to have elevated C-reactive protein concentrations. Weight loss induces a change in this protein, and single nucleotide polymorphisms in regulating genes might affect this change, since C-reactive protein concentration is known to be approximately 40-50% heritable. Our aim was to study the association between the IL6 -174(G/C), IL1B +3,954(C/T) and CRP +1,059(G/C) single nucleotide polymorphisms, and CRP concentrations in obese men during a weight reduction program. We genotyped 72 obese men who had participated in a weight reduction program. Their C-reactive protein concentrations, interleukin-6 levels and fat mass were determined at two time points: at baseline and after weight reduction (after 2 months). After weight reduction, the mean weight loss was 14.3 kg. Median C-reactive protein concentrations decreased, after weight reduction, from 1.72 to 1.22 mg/l (p < 0.02). The baseline C-reactive protein concentration did not differ between the IL6-174(G/C) genotypes, but after weight loss, concentrations differed (p = 0.03 Kruskal-Wallis test); the highest concentration was found in the CC genotype (CC 1.01 versus GG 1.93 mg/l, p = 0.007 ANOVA post-hoc test). This change in concentration was associated with the IL6-174(G/C) genotype (p = 0.01, Kruskal-Wallis test), being least in the CC genotype. The other single nucleotide polymorphisms studied were not associated with CRP concentrations. Our results show that, at baseline, there is no difference in C-reactive protein concentrations among the different IL6-174(G/C) genotypes, but after weight loss the CC genotype is associated with highest C-reactive protein concentrations, resulting from the fact that C-reactive protein seems not to decrease with weight loss in this genotype.  相似文献   
323.
Four Atlantic salmon Salmo salar stocks in the Baltic Sea, varying in their breeding history, were studied for changes in life‐history traits over the years 1972–1995. Total length (LT) at age of captured (LTC) fish had increased throughout the study period, partly due to increased temperature and increased LT at release, (LTR) but also due to remaining cohort effects that could represent unaccounted environmental or genetic change. Simultaneously, maturation probabilities controlled for water temperature, LTC and LTR had increased in all stocks. The least change was observed in the River Tornionjoki S. salar that was subject only to supportive stockings originating from wild parents. These results suggest a long‐term divergence between semi‐natural and broodstock‐based S. salar stocks. Increased LT at age explained advanced maturation only marginally, and it remains an open question to what extent the generally increased probabilities to mature at early age reflected underlying genetic changes.  相似文献   
324.
325.
We developed a novel strategy based on in vitro DNA transposition of phage Mu to construct vectors for "knock-in" of the gene encoding Cre recombinase into endogenous loci in embryonic stem cells. This strategy was used to introduce Cre into the mouse Meox1 locus, which was expected to drive Cre expression in the presomitic and somitic mesoderm. In embryos heterozygous for both Meox1(Cre) and R26R or Z/AP reporter alleles, specific and efficient recombination of the reporter alleles was detected in the maturing somites and their derivatives, including developing vertebrae, skeletal muscle, back dermis, as well as endothelium of the blood vessels invading the spinal cord and developing limbs. In contrast to the somitic mesoderm, Cre activity was not observed in the cranial paraxial mesoderm. Thus, the Meox1(Cre) allele allows detailed fate-mapping of Meox1-expressing tissues, including derivatives of the somitic mesoderm. We used it to demonstrate dynamic changes in the composition of the mesenchyme surrounding the developing inner ear. Meox1(Cre) may also be used for tissue-specific mutagenesis in the somitic mesoderm and its derivatives.  相似文献   
326.
Conflict between the sexes over mating decision may result in antagonistic coevolution in structures that increase control over copulation. In Aquarius paludum both females and males have long abdominal spines. We tested the hypothesis that abdominal spines increase female ability to resist male mating attempts and reduce the costs of mating in A. paludum. We manipulated female spine length and observed female mating and egg-production rate in two different studies. We found that females with intact spines succeeded to reject male mating attempt more often than females with removed spines. Intact females also mated less often than females with removed or shortened spines. Male presence and mating rate increased female egg number. Our results thus support the hypothesis that abdominal spines help female to reject male mating attempts but contrary to predictions, we found that A. paludum females somehow benefit from multiple matings in spite of the sexual conflict.  相似文献   
327.
Lifestyle modification to decrease cardiovascular disease (CVD) risk has recently been reaffirmed by both the National Cholesterol Education Program and American Heart Association (AHA). Using a randomized crossover design, the Therapeutic Lifestyle Change (TLC)/Step 2 diet relative to a typical Western diet was assessed in 36 moderately hypercholesterolemic subjects in a clinical setting under isoweight conditions. Mean lipoprotein and apolipoprotein levels (fasting and non-fasting), fatty acid profiles, parameters of HDL metabolism, and glucose homeostasis were determined. Relative to the Western diet, the TLC/Step 2 diet resulted in 11% and 7% lower LDL cholesterol (LDL-C) and HDL cholesterol (HDL-C), respectively, with no significant change in TG levels or total cholesterol-HDL-C ratio. Similar responses were observed in the non-fasting state. Linoleic (18:2n-6c) and alpha-linolenic (18:3n-3) acids increased at the expense of oleic acid (18:1n-9c) in the cholesteryl ester, TG, and phospholipid subfractions. The dietary changes had no significant effect on fractional esterification rate of HDL, phospholipid transfer protein (PLTP), or cholesterol ester transfer protein activities, or glucose and insulin levels. Female and male subjects responded similarly. The TLC/Step 2 diet resulted in a decrease in some CVD risk factors and no apparent adverse effects in others.  相似文献   
328.
Escherichia coli MG1655 cells expressing novel bacterial hemoglobin and flavohemoglobin genes from a medium-copy-number plasmid were grown in shake flask cultures under nitrosative and oxidative stress. E. coli cells expressing these proteins display enhanced resistance against the NO(.) releaser sodium nitroprusside (SNP) relative to that of the control strain bearing the parental plasmid. Expression of bacterial hemoglobins originating from Campylobacter jejuni (CHb) and Vitreoscilla sp. (VHb) conferred resistance on SNP-challenged cells. In addition, it has been shown that NO(.) detoxification is also a common feature of flavohemoglobins originating from different taxonomic groups and can be transferred to a heterologous host. These observations have been confirmed in a specific in vitro NO(.) consumption assay. Protein extracts isolated from E. coli strains overexpressing flavohemoglobins consumed authentic NO(.) more readily than protein extracts from the wild-type strain. Oxidative challenge to the cells evoked nonuniform responses from the various cell cultures. Improved oxidative-stress-sustaining properties had also been observed when the flavohemoglobins from E. coli, Klebsiella pneumoniae, Deinococcus radiodurans, and Pseudomonas aeruginosa were expressed in E. coli.  相似文献   
329.
Ionotropic glutamate receptor (iGluR) subunits contain a approximately 400-residue extracellular N-terminal domain ("X domain"), which is sequence-related to bacterial amino acid-binding proteins and to class C G-protein-coupled receptors. The X domain has been implicated in the assembly, transport to the cell surface, allosteric ligand binding, and desensitization in various members of the iGluR family, but its actual role in these events is poorly characterized. We have studied the properties of homomeric alpha-amino-3-hydroxy-5-methylisoxazolepropionate (AMPA)-selective GluR-D glutamate receptors carrying N-terminal deletions. Our analysis indicates that, surprisingly, transport to the cell surface, ligand binding properties, agonist-triggered channel activation, rapid desensitization, and allosteric potentiation by cyclothiazide can occur normally in the complete absence of the X domain (residues 22-402). The relatively intact ligand-gated channel function of a homomeric AMPA receptor in the absence of the X domain indirectly suggests more subtle roles for this domain in AMPA receptors, e.g. in the assembly of heteromeric receptors and in synaptic protein interactions.  相似文献   
330.
Infusions of boronophenylalanine-fructose complex (BPA-F), at doses up to 900 mg/kg of BPA and 860 mg/kg of fructose, have been used to deliver boron to cancer tissue for boron neutron capture therapy (BNCT). In patients with phenylketonuria (PKU), phenylalanine accumulates, which is harmful in the long run. PKU has been an exclusion criterion for BPA-F-mediated BNCT. Fructose is harmful to individuals with hereditary fructose intolerance (HFI) in amounts currently used in BNCT. The harmful effects are mediated through induction of hypoglycemia and acidosis, which may lead to irreversible organ damage or even death. Consequently, HFI should be added as an exclusion criterion for BNCT if fructose-containing solutions are used in boron carriers. Non-HFI subjects may also develop symptoms, such as gastrointestinal pain, if the fructose infusion rate is high. We therefore recommend monitoring of glucose levels and correcting possible hypoglycemia promptly. Except for some populations with extremely low PKU prevalence, HFI and PKU prevalences are similar, approximately 1 or 2 per 20,000.  相似文献   
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