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741.

Objective

HIV/HCV co-infection is characterised by accelerated progression of liver disease. Recently, the rsl2979860 C/T polymorphism in the IL28B gene has been linked to progression towards cirrhosis in HCV mono-infected patients and to treatment response of HCV-infection in HIV/HCV co-infected patients. Our aim was to clarify by non-invasive techniques if this polymorphism affects fibrosis progression in HIV/HCV co-infection.

Methods

In a cross-sectional design, liver stiffness (transient elastography), surrogate markers of liver fibrosis (APRI and FIB-4 scores) and rsl2979860 genotypes were analysed in 84 HCV/H1V co-infected patients. IL28B genotypes were determined by real-time PCR using a light cycler. In 56 HIV/HCV co-infected patients we also studied progression of fibrosis in relation to rsl2979860 C/T genotypes over two years.

Results

82% of the patients were on HAART (74% without detectable HI viremia) and 67% were haemophiliacs, respectively. HCV genotype 1 was present in 62%. Cross-sectional median liver stiffness was 7.4 kPa and correlated with APRI and FIB-4 scores (r = 0.6 each, p < 0.001). Frequencies of IL28B genotypes were: CC 50%, CT 43% and TT 7%. In the cross-sectional analysis liver stiffness values were not different between the various IL28B-genotypes. Upon follow-up under HAART carriers of a C allele did not show further progression, while liver stiffness significantly increased in HIV/HCV co-infected patients with the T allele (p = 0.047).

Conclusion

Although progression of liver fibrosis was low under HAART in our cohort, progression was more pronounced in HIV/HCV genotype 1 co-infected patients with the T allele.  相似文献   
742.
743.
Disparities in access to healthy foods have been identified particularly in the United States. Fewer studies have measured the effects these disparities have on diet-related health outcomes. This study measured the association between the presence of food establishments and obesity among 1295 adults living in the southern region of the United States. The prevalence of obesity was lower in areas that had supermarkets and higher in area with small grocery stores or fast food restaurants. Our findings are consistent with other studies showing that types of food stores and restaurants influence food choices and, subsequently, diet-related health outcomes.  相似文献   
744.

Background  

Measures to assess neighborhood environments are needed to better understand the salient features that may enhance outdoor physical activities, such as walking and bicycling for transport or leisure. The purpose of this study was to derive constructs to describe neighborhoods using both primary (neighborhood audit) and secondary (geographic information systems) data.  相似文献   
745.
ObjectivePhysical activity is recommended for pregnant women without medical or obstetric complications. This study described the prevalence and correlates of objectively-measured physical activity and sedentary behavior among United States pregnant women.MethodsUsing cross-sectional data collected from the 2003 to 2006 National Health and Nutrition Examination Survey (NHANES), 359 pregnant women ≥16 years wore an accelerometer for 1 week.ResultsWomen participated in a mean of 12.0 minutes/day (standard error (SE) 0.86) of moderate activity and 0.3 minutes/day (SE 0.08) of vigorous activity. Mean moderate to vigorous physical activity varied by trimester: 11.5 minutes/day in first trimester, 14.3 minutes/day in second trimester, and 7.6 minutes/day in third trimester. On average, women spent 57.1% of their monitored time in sedentary behaviors. In multivariable adjusted models, moderate to vigorous physical activity was higher in the first (p = 0.02) and second (p < 0.001) trimesters compared to the third trimester, and among women with higher household income (p = 0.03) compared to lower household income. In multivariable adjusted models, average counts/minute was higher in the second compared to the third trimester (p = 0.04).ConclusionMost pregnant women spent more than half of the monitored day in sedentary behaviors and did not meet recommendations for physical activity.  相似文献   
746.
This study compares the relative effects of advancing male age on multiple genomic defects in human sperm [DNA fragmentation index (DFI), chromatin integrity, gene mutations, and numerical chromosomal abnormalities], characterizes the relationships among these defects and with semen quality, and estimates the incidence of susceptible individuals for a well characterized nonclinical nonsmoking group of 97 men (22-80 years). Adjusting for confounders, we found major associations between age and the frequencies of sperm with DFI and fibroblast growth factor receptor 3 gene (FGFR3) mutations associated with achondroplasia (P < 0.01) with no evidence for age thresholds. However, we found no associations between age and the frequencies of sperm with immature chromatin, aneuploidies/diploidies, FGFR2 mutations (Apert syndrome), or sex ratio in this cohort. There were also no consistent correlations among genomic and semen-quality endpoints, except between DFI and sperm motility (r = -0.65, P < 0.001). These findings suggest there are multiple spermatogenic targets for genomically defective sperm with substantially variable susceptibilities to age. Our findings predict that as healthy males age, they have decreased pregnancy success with trends beginning in their early reproductive years, increased risk for producing offspring with achondroplasia mutations, and risk of fathering offspring with Apert syndrome that may vary across cohorts, but with no increased risk for fathering aneuploid offspring (Down, Klinefelter, Turner, triple X, and XYY syndromes) or triploid embryos. Our findings also suggest that the burden of genomic damage in sperm cannot be inferred from semen quality, and that a small fraction of men are at increased risk for transmitting multiple genetic and chromosomal defects.  相似文献   
747.
In complex partial epilepsy and in animal models of epilepsy, hippocampal mossy fibers appear to develop recurrent collaterals, that invade the dentate molecular layer. Mossy fiber collaterals have been proposed to subserve recurrent excitation by forming granule cell-granule cell synapses. This hypothesis was tested by visualizing dentate granule cells and their mossy fibers after terminal uptake and retrograde transport of biocytin. Labeling studies were performed with transverse slices of the caudal rat hippocampal formation prepared 2.6–l70.0 weeks after pilocarpine-induced or kainic acid-induced status epilepticus. Light microscopy demonstrated the progressive growth of recurrent mossy fibers into the molecular layer; the densest innervation was observed in slices from pilocarpine-treated rats that had survived 10 weeks or longer after status epilepticus. Thin mossy fiber collaterals originated predominantly from deep within the hilar region, crossed the granule cell body layer, and formed an axonal plexus oriented parallel to the cell body layer within the inner one-third of the molecular layer. When sprouting was most robust, some recurrent mossy fibers at the apex of the dentate gyrus reached the outer two-thirds of the molecular layer. The distribution and density of mossy fiber-like Timm staining correlated with the biocytin labeling. When viewed with the electron microscope, the inner one-third of the dentate molecular layer contained numerous mossy fiber boutons. In some instances, biocytin-labeled mossy fiber boutons were engaged in synaptic contact with biocytin-labeled granule cell dendrites. Granule cell dendrites did not develop large complex spines (“thorny excrescences”) at the site of synapse formation, and they did not appear to have been permanently damaged by seizure activity. These results establish the validity of Timm staining as a marker for mossy fiber sprouting and support the view that status epilepticus provokes the formation of a novel recurrent excitatory circuit in the dentate gyrus. Retrograde labeling with biocytin showed that the recurrent mossy fiber projection often occupies a considerably greater fraction of the dendritic region than previous studies had suggested. © 1995 Wiley-Liss, Inc.  相似文献   
748.
BACKGROUND: Hyalinizing trabecular adenoma (HTA) is an uncommon benign thyroid tumor that can present as a solitary thyroid nodule, a prominent nodule in a multinodular goiter, or as an incidental finding in a thyroidectomy specimen. The clinical significance of the lesion is that it is frequently misdiagnosed as papillary carcinoma on fine-needle aspiration cytology or as papillary or medullary carcinoma on histopathological section. We reviewed our recent experience with 7 patients diagnosed with HTA. METHODS: Fine-needle aspiration biopsy was performed in 7 patients presenting with a solitary thyroid nodule (n = 4) or a multinodular goiter (n = 3). The patients underwent total thyroidectomy (n = 6) or hemithyroidectomy (n = 1). RESULTS: In 4 patients, the preoperative cytology was suggestive of papillary carcinoma, in 2 patients suspicious, and in 1 patient positive for papillary carcinoma. On histopathological section, 2 patients had a microscopic HTA, 2 patients had HTA in 1 or 2 nodules of a multinodular goiter, and 3 patients had HTA in a solitary nodule. Except in 1 patient, who had a microscopic focus (3.2 mm) of papillary carcinoma, there was no evidence of malignancy in the surgical specimens on permanent histopathological section. CONCLUSIONS: Although HTA is a rare condition of the thyroid, the surgeon needs to be aware of this entity to be able to better discuss the pathological findings with the patient, particularly since some pathologists and endocrinologists believe that HTA may represent a malignant neoplasm of low metastatic potential.  相似文献   
749.
Arteriovenous malformations (AVMs) are vascular lesions in which an overgrowth of blood vessels of varying sizes develops with one or more direct connections between the arterial and venous circulation. We performed a retrospective review of a cohort of 54 patients with AVMs referred to our clinical genomic laboratory for high-depth next-generation sequencing (NGS) panel of Disorders of Somatic Mosaicism (DoSM). Thirty-seven of 54 patients were female (68.5%). Among the 54 cases, 37 (68.5%) cases had pathogenic and/or likely pathogenic (P/LP) variants identified, two cases (3.7%) had variants of uncertain clinical significance, and the remaining 15 cases (27.8%) had negative results. MAP2K1 variants were found in 12 cases, followed by eight cases with KRAS variants and seven with TEK variants, and the remainder being identified in several other genes on the panel. Among the 37 positive cases, 32 cases had somatic alterations only; the remaining five cases had at least one germline P/LP variant, including four cases with PTEN and one with RASA1. Of note, two cases had the unexpected co-existence of two P/LP variants. In summary, this study illustrated the molecular diagnostic yield (68.5%) of this cohort of patients with a clinical indication of AVMs by our high-depth DoSM NGS panel.  相似文献   
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