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241.
HIV-1 infection in India has been increasing steadily over the last decade. In the absence of potent antiviral therapy, estimates of HIV infection are needed to monitor the epidemic, institute prevention strategies in target populations and determine the suitable populations for vaccine studies. In this report we present the HIV-1 seroprevalence and annual estimates of seroincidence in a high risk population from Calcutta, the most populous city in the eastern part of India. In 1206 high risk subjects tested over two years between February of 1999 and December 2000, we have determined an overall seroprevalence of 40.1% using enzyme-linked immunosorbent assay followed by a confirmatory Western blot testing. Furthermore, using a newly described Standardized Testing Algorithm for Recent HIV-1 Seroconversion (STARHS), we have estimated an annual seroincidence rate of about 7% in this population during this two-year study. Such a high annual seroincidence rate makes this population well suited for studies of HIV-1 prevention, including vaccine trials.  相似文献   
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A case of atypical dengue haemorrhagic fever is being described in a 30 years old male along with a short discussion on the subject.  相似文献   
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We have developed an enzyme-linked immunosorbent assay for quantitating human immunoglobulin A in human secretions and serum. The procedure uses Immunobeads as the solid phase, has a sensitivity of 10 ng/ml, and can be completed in 1 day. Since there is no diffusion through agar, the assay does not require a correction factor when measuring secretory immunoglobulin A. This method should be useful in studies of local mucosal immunity in humans, especially when a very sensitive assay is needed.  相似文献   
245.

Introduction

HIV-1 near full-length genome (HIV-NFLG) sequencing from plasma is an attractive multidimensional tool to apply in large-scale population-based molecular epidemiological studies. It also enables genotypic resistance testing (GRT) for all drug target sites allowing effective intervention strategies for control and prevention in high-risk population groups. Thus, the main objective of this study was to develop a simplified subtype-independent, cost- and labour-efficient HIV-NFLG protocol that can be used in clinical management as well as in molecular epidemiological studies.

Methods

Plasma samples (n=30) were obtained from HIV-1B (n=10), HIV-1C (n=10), CRF01_AE (n=5) and CRF01_AG (n=5) infected individuals with minimum viral load >1120 copies/ml. The amplification was performed with two large amplicons of 5.5 kb and 3.7 kb, sequenced with 17 primers to obtain HIV-NFLG. GRT was validated against ViroSeq™ HIV-1 Genotyping System.

Results

After excluding four plasma samples with low-quality RNA, a total of 26 samples were attempted. Among them, NFLG was obtained from 24 (92%) samples with the lowest viral load being 3000 copies/ml. High (>99%) concordance was observed between HIV-NFLG and ViroSeq™ when determining the drug resistance mutations (DRMs). The N384I connection mutation was additionally detected by NFLG in two samples.

Conclusions

Our high efficiency subtype-independent HIV-NFLG is a simple and promising approach to be used in large-scale molecular epidemiological studies. It will facilitate the understanding of the HIV-1 pandemic population dynamics and outline effective intervention strategies. Furthermore, it can potentially be applicable in clinical management of drug resistance by evaluating DRMs against all available antiretrovirals in a single assay.  相似文献   
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Summary

Association between warfarin use and fracture risk is unclear. We examined the association between long-term warfarin use and fracture risk at the hip, spine, and wrist in elders. No significant association was found between long-term warfarin use and fracture risk, despite biological plausibility.

Introduction

Prior studies examining the association of warfarin use and osteoporotic fractures have been conflicting, potentially related to methodological limitations. Thus, we examined the association of long-term warfarin use with risk of hip, spine, and wrist fractures among older adults with atrial fibrillation, attempting to address prior methodologic challenges.

Methods

We included men and women ≥65 years of age with incident atrial fibrillation and without prior history of fractures from The Health Improvement Network followed between 2000 and 2010. Long-term warfarin use was defined in two ways: (1) warfarin use ≥1 year; (2) warfarin use ≥3 years. Propensity-score matched cohorts of warfarin users and nonusers were created to evaluate the association between long-term warfarin use and risk of hip, spine, and wrist fractures separately as well as combined, using Cox-proportional hazards regression models.

Results

Among >20,000 participants with incident atrial fibrillation, the hazard ratios (HR) for hip fracture with warfarin use ≥1 and ≥3 years, respectively, were 1.08 (95%CI 0.87, 1.35) and 1.13 (95 % CI 0.84, 1.50). Similarly, no significant associations were observed between long-term warfarin use and risk of spine or wrist fracture. When risk of any fracture was assessed with warfarin use, no association was found [HR for warfarin use ≥1 year 0.92 (95%CI 0.77, 1.10); HR for warfarin use ≥3 years 1.12 (95%CI 0.88, 1.43)].

Conclusions

Long-term warfarin use among elders with atrial fibrillation was not associated with increased risk of osteoporotic fractures and therefore does not appear to necessitate additional surveillance or prophylaxis.  相似文献   
248.

Objective

To examine whether giant cell arteritis (GCA) is associated with increased all‐cause mortality and whether mortality differs according to age, sex, and calendar year of cohort entry.

Methods

Using the UK‐based Clinical Practice Research Datalink, we identified 9,778 newly diagnosed GCA patients from 1990–2014, and up to 10 nonvasculitis patients randomly matched to each case on age, sex, practice, and years of history before cohort entry. We used Cox regression to estimate adjusted hazard ratios (HRs) for mortality of GCA patients in comparison to nonvasculitis patients, then stratified by age, sex, and calendar year of cohort entry.

Results

Compared with nonvasculitis patients, GCA patients had increased mortality during the first year following diagnosis (adjusted HR 1.51, 95% confidence interval [95% CI] 1.40–1.64), and marginally increased mortality between 1 and 5 years after the diagnosis (adjusted HR 1.16, 95% CI 1.09–1.23), but not >5 years after the diagnosis (adjusted HR 1.06, 95% CI 1.00–1.12). GCA patients diagnosed before age 65 years had the highest mortality risk during the first year following diagnosis (adjusted HR 2.32, 95% CI 1.60–3.35). The mortality risk did not differ substantially by sex or calendar year of cohort entry.

Conclusion

GCA patients had an increased risk of mortality during the period shortly after the GCA diagnosis, in particular during the first year, but no increased risk after 5 years postdiagnosis. The mortality risk differed by age with an even greater increased 1‐year mortality in those age <65 years at diagnosis, but not by sex or calendar year of cohort entry.
  相似文献   
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