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1.
Two methods have been developed for the rapid and accurate estimation of orthophosphate in the presence of Triton X-100. The first is unaffected by up to 2.0–2.5% (v/v) of the detergent in the assay samples, while the second method is essentially unaffected by Triton X-100 and is also suitable for use in the presence of acid labile organic phosphate. Both are proportional in the range 0.05–1.0 μmole of orthophosphate in the assay.  相似文献   
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M C Wang  L C See 《Biometrics》1992,48(1):129-141
It is a common sampling scheme in retrospective studies that the data set includes only individuals who satisfy a certain sampling criterion. In this paper we consider the situation when the sampling criterion is a specified event, and assume that an earlier event can be retrospectively identified given the occurrence of the specified event. A semiparametric method, which is a compromise between nonparametric and parametric methods, is employed for the estimation of the expected number of the specified events (namely, the N-estimation) occurring in arbitrarily given intervals. A number of statistical properties of the estimates are developed. Due to the limitation of semiparametric models, our estimates should be regarded as conservative estimates since in general they underestimate the actual number of the specified events. This type of limitation, however, cannot be avoided with nonparametric or semiparametric models. Applications to acquired immunodeficiency syndrome (AIDS) cases are considered. The blood transfusion AIDS cases reported to the Centers for Disease Control are analyzed in detail.  相似文献   
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Male schizophrenia patients are known to have a heavier smoking pattern compared with the general population. However, the mechanism for this association is not known, though hypothesis that smoking could alleviate symptomatology of schizophrenia and reduce side effects of antipsychotics has been suggested. The aims of this study were to validate the heavier smoking pattern among male schizophrenia patients and to investigate the possible mechanisms for the association. To enhance the reliability of the study, we recruited two large independent samples with 604 and 535 male Chinese schizophrenia patients, and compared their smoking pattern with that of 535 healthy male controls recruited from general population. Validated multiple indicators and multiple causes structure equation model and regression models were used to investigate the association of smoking with factors of schizophrenia symptomatology and with the usage of antipsychotics and their extra-pyramidal side effects (EPS). Schizophrenia patients had significantly heavier smoking pattern compared with healthy controls in our sample (42.4% vs. 16.8%, p<0.001 for current smoking prevalence; 23.5% vs. 43.3%, p<0.001 for smoking cessation rate; 24.5% vs. 3.0%, p<0.001 for heavy smoker proportion). Their smoking status was also found to be consistently and significantly associated with reduced negative factor scores for schizophrenia symptomatology (β = −0.123, p = 0.051 for sample-A; β = −0.103, p = 0.035 for sample-B; β = −0.082, p = 0.017 for the combined sample). However, no significant association was found between smoking and antipsychotics usage or risk of EPS. These results support that smoking is associated with improved negative symptoms, which could account for the heavier smoking pattern among schizophrenia patients.  相似文献   
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CDK5RAP2 is a centrosomal protein known to be involved in the regulation of the γ-tubulin ring complex and thus the organization of microtubule arrays. However, the mechanism by which CDK5RAP2 is itself recruited to centrosomes is poorly understood. We report here that CDK5RAP2 displays highly dynamic attachment to centrosomes in a microtubule-dependent manner. CDK5RAP2 associates with the retrograde transporter dynein-dynactin and contains a sequence motif that binds to dynein light chain 8. Significantly, disruption of cellular dynein-dynactin function reduces the centrosomal level of CDK5RAP2. These results reveal a key role of the dynein-dynactin complex in the dynamic recruitment of CDK5RAP2 to centrosomes.  相似文献   
6.
As malfunction/absence of immune cells causes a variety of immunosuppressive disorders and chemical synthetic drugs for curing these diseases have many adverse effects, vigorous studies are being conducted. The Acanthopanax family has been used as traditional medicines for gastric ulcer, diabetes, etc. and culinary materials in East-South Asia. In this study, the immunostimulating properties of A. sessiliflorus were evaluated. A. sessiliflorus increased not only the splenocyte number but also immune-related cytokines such as TNF-α. However, it could not upregulate the expressions of IFN-γ and IL-2. A. sessiliflorus increased the swimming time, and comparison of organ weights relative to body weights for immune-related organs such as the spleen and thymus after a forced swim test showed that it could recover the spleen and thymus weights. It also increased the expression of TNF-α and slightly increased the concentration of IFN-γ but not IL-2. From the results, we concluded that as A. sessiliflorus has not only a host defense effect but also a stress-ameliorating property, further study it will be a promising material of immunostimulating material.  相似文献   
7.
Fine root decomposition constitutes a critical yet poorly understood flux of carbon and nutrients in terrestrial ecosystems. Here, we present the first large‐scale synthesis of species trait effects on the early stages of fine root decomposition at both global and local scales. Based on decomposition rates for 279 plant species across 105 studies and 176 sites, we found that mycorrhizal association and woodiness are the best categorical traits for predicting rates of fine root decomposition. Consistent positive effects of nitrogen and phosphorus concentrations and negative effects of lignin concentration emerged on decomposition rates within sites. Similar relationships were present across sites, along with positive effects of temperature and moisture. Calcium was not consistently related to decomposition rate at either scale. While the chemical drivers of fine root decomposition parallel those of leaf decomposition, our results indicate that the best plant functional groups for predicting fine root decomposition differ from those predicting leaf decomposition.  相似文献   
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Purpose

To estimate the rate of hospitalized eye trauma in Taiwan and investigate the role between principal and secondary diagnoses of such trauma.

Methods

Nationwide fixed cohort study of 1,000,000 beneficiaries from the Taiwan Longitudinal Health Database was used and 4819 patients who were hospitalized for eye trauma during 1996-2010 were analyzed.

Results

During 1996-2010, the incidence rates of hospitalized eye trauma (per 100 000 person-years) were 35.0 (95% confidence interval (CI), 34.0 to 36.0) for total diagnosis, 9.8 (95% CI, 9.3 to 10.3) for a principal diagnosis, and 25.3 (95% CI, 24.4 to 26.1) for a secondary diagnosis. The sex risk ratio was 3.1 for a principal diagnosis and 2.1 for a secondary diagnosis. The main causes of eye trauma were traffic accident, work accident, assault (among males <60 years of age), and falls (among elderly men and women). The proportion admitted to an ophthalmic department among those with a principal diagnosis of eye trauma (64.8%) was significantly higher than among those with a secondary diagnosis (2.3%) (p<.0001). Patients with a principal diagnosis of eye trauma had shorter hospital stays (7.1±10.2 days) and lower fatality (0.07%) than those with a secondary diagnosis of eye trauma (10.0±31.6 days and 0.3%, respectively).

Conclusion

Data only from ophthalmic admissions tends to underestimate the true incidence rate of hospitalized eye trauma. Patients with a principal diagnosis of eye trauma had less severe injuries than did those with a secondary diagnosis.  相似文献   
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