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Start time has been shown to be a significant predictor of overall performance in the sport of luge. The starting motion in luge has been described as an explosive upper-body movement that requires significant technique and skill to perfect. This study aims to investigate upper-body factors that may relate to start time in luge. Twenty-two subjects participated in the study as part of their normal off-season training. Each subject had a minimum of 3 years' experience in the sport of luge, and at the time was a member of a U.S. Luge National Team. Subjects completed a 1 repetition maximum (1RM) in the bench press (BP), prone row (PR), and weighted pull-up (WP). Anthropometric distances were taken measuring finger-tip span (FS), biacromial breadth (BB), acromio-radial length, acromio-olecranon length (AO), hand length, and sitting cervical height. Subjects were divided into 2 groups based on which U.S. Luge National team they were currently a member of, Senior National (SN, n = 13) and Junior National (JN, n = 9). A Pearson product-moment correlation coefficient showed several significant (p ≤ 0.05) relationships between upper-body variables and start time among the groups. The BP and PR 1RM were shown to have a significant relationship in both groups. Among the anthropometric variables, AO was also significant in both groups. The WP, FS, BB, and height were all shown to have a significant relationship with start time in the SN group, but not in the JN group. These results suggest that as luge athletes become more efficient in the starting technique, outside factors such as upper-body strength and anthropometric measures play a larger role in performance.  相似文献   
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Elevated levels of interleukin-1 (IL-1) have been shown to amplify the inflammatory response against periodontopathogenic bacteria. In humans, polymorphisms in the IL1A and IL1B genes are the most well-studied genetic polymorphisms associated with periodontal disease (PD). In contrast to human, there is a lack of knowledge on the genetic basis of canine PD. A case–control study was conducted in which a molecular analysis of dog IL1A and IL1B genes was performed. Of the eight genetic variants identified, seven in IL1A gene and one in IL1B gene, IL1A/1_g.388A >C and IL1A/1_g.521T >A showed statistically significant differences between groups (adjusted OR (95% CI): 0.15 (0.03–0.76), P= 0.022; 5.76 (1.03–32.1), P= 0.046, respectively). It suggests that in the studied population the IL1A/1_g.388C allele is associated with a decreased PD risk, whereas the IL1A/1_g.521A allele can confer an increased risk. Additionally, the IL1A/2_g.515G >T variation resulted in a change of amino acid, i.e. glycine to valine. In silico analysis suggests that this change can alter protein structure and function, predicting it to be deleterious or damaging. This work suggests that IL1 genetic variants may be important in PD susceptibility in canines.  相似文献   
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Background

Pandemic influenza poses a serious threat to global health and the world economy. While vaccines are currently under development, passive immunization could offer an alternative strategy to prevent and treat influenza virus infection. Attempts to develop monoclonal antibodies (mAbs) have been made. However, passive immunization based on mAbs may require a cocktail of mAbs with broader specificity in order to provide full protection since mAbs are generally specific for single epitopes. Chicken immunoglobulins (IgY) found in egg yolk have been used mainly for treatment of infectious diseases of the gastrointestinal tract. Because the recent epidemic of highly pathogenic avian influenza virus (HPAIV) strain H5N1 has resulted in serious economic losses to the poultry industry, many countries including Vietnam have introduced mass vaccination of poultry with H5N1 virus vaccines. We reasoned that IgY from consumable eggs available in supermarkets in Vietnam could provide protection against infections with HPAIV H5N1.

Methods and Findings

We found that H5N1-specific IgY that are prepared from eggs available in supermarkets in Vietnam by a rapid and simple water dilution method cross-protect against infections with HPAIV H5N1 and related H5N2 strains in mice. When administered intranasally before or after lethal infection, the IgY prevent the infection or significantly reduce viral replication resulting in complete recovery from the disease, respectively. We further generated H1N1 virus-specific IgY by immunization of hens with inactivated H1N1 A/PR/8/34 as a model virus for the current pandemic H1N1/09 and found that such H1N1-specific IgY protect mice from lethal influenza virus infection.

Conclusions

The findings suggest that readily available H5N1-specific IgY offer an enormous source of valuable biological material to combat a potential H5N1 pandemic. In addition, our study provides a proof-of-concept for the approach using virus-specific IgY as affordable, safe, and effective alternative for the control of influenza outbreaks, including the current H1N1 pandemic.  相似文献   
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Two 1-thia-DCK analogues (9a and 9b) were synthesized and evaluated for inhibition of HIV-1 replication in H9 lymphocytes. Compound 9a showed excellent anti-HIV activity with an EC(50) value of 0.00012 microM and therapeutic index of 1408000. Compound 9b was less active with EC(50) and TI values of 3.11 microM and 62.3, respectively. The bioassay results indicated that thia-DCK analogues merit attention as potential HIV-1 inhibitors.  相似文献   
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The nucleic acid synthesis in normal viable housefly eggs and non-viable housefly eggs deposited by flies chemosterilized by apholate and thiotepa has been studied. During normal embryonic development, there is a rapid many-fold increase in DNA after an initial lag period. In the chemosterilized eggs there is almost no increase in DNA, but some accumulation of the deoxyribosidic components of the acid-soluble extract. The effect on the levels of RNA and ribosidic components of the acid-soluble extract is less apparent.The nucleotide ratios of normal housefly eggs has been determined to be similar to that reported for other insect eggs. Apholate-sterilized eggs were significantly lower in adenylic acid than normal fly-egg RNA. The RNA of the thiotepa sterilized eggs was a little lower in guanylic acid and contained an unidentified compound not present in normal egg RNA.When thiotepa P32 was the chemosterilant, all components of the isolated sodium RNA were labelled. This suggests that thiotepa may have been degraded and the resulting inorganic phosphate reincorporated into the RNA. There was no evidence of alkylated guanine in the RNA.  相似文献   
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