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41.
Cocultures of fibroblasts and keratinocytes, physically separated by a membrane, were carried out for 48 h, and large-scale gene expression in the fibroblasts was analyzed by Affymetrix microarrays of expressed mRNAs. Two independent experiments were performed with cells from different individuals. A total of 243 genes were upregulated twofold or more and 100 genes were negatively regulated (reduction by half or more) in both experiments. A total of 69 of these 343 genes coded for growth factors, cytokines, chemokines, or their receptors; extracellular matrix molecules or enzymes involved in their synthesis; adhesion receptors; proteinases/proteinase inhibitors or their receptors; cell cycle regulators; apoptosis-regulating factors; prostaglandin-related factors; or growth-factor-binding proteins. Most of the remaining genes coded for proteins involved in signal transduction or general metabolism. Sixteen genes selected from these groups were further analyzed by northern blot analysis to confirm the array data. Finally, experiments with interleukin-1 alpha (IL-1 alpha)-blocking antibodies or IL-1 receptor antagonists demonstrate that IL-1 alpha is one important factor involved in keratinocyte-mediated regulation of gene expression in fibroblasts. Taken together, the results suggest that keratinocytes regulate fibroblast gene expression with implications for the wound healing process during reepithelialization.  相似文献   
42.
A novel presenilin-1 (PS1) mutation (P117S) in an American pedigree is described. We compare clinical, neuropathological and cell culture phenotypes produced by this mutation with another codon 117 mutation that was earlier discovered by our group in a Polish kindred. Both mutations are associated with an unusually severe Alzheimer disease (AD) phenotype, with the onset starting before the third decade of life, rapid disease progression and acute presentation of clinical symptoms. The severity of clinical phenotype was closely correlated with the abundance of pathology: massive deposition of Abeta42 in plaques, severe neurofibrillary degeneration and neuronal loss. When overexpressed in mouse neuroblastoma N2a cells, both mutations caused loss of an ability to promote neurite outgrowth and produced an increase in the ratio of secreted Abeta42/40 amyloid peptides. In stably transfected N2a cell lines only mutant proteins were endoproteolytically cleaved indicating some dependability of this process on the presence of mutation. Taken together, our results show that clinical and cell culture phenotypes produced by these 2 codon 117 mutations are closely related suggesting that the pathogenic action of PS1 may involve effect on neurite outgrowth and endoproteolytic cleavage of the full-length protein. Given the high potency in vivo and in vitro of both codon 117 mutations, this site of PS1 must be particularly important for its normal/pathogenic function.  相似文献   
43.
A probabilistic functional atlas of the human subthalamic nucleus   总被引:1,自引:0,他引:1  
This paper introduces a method for generation and validation of a probabilistic functional brain atlas of subcortical structures from electrophysiological and neuroimaging data. The method contains three major steps: (1) acquisition of pre, intra, and postoperative multimodal data; (2) selection of an accurate data set for atlas generation; and (3) generation of the atlas from the selected data set. The method is applied to construct the probabilistic functional atlas of the human subthalamic nucleus (STN). The STN atlas has been built from data collected during surgical treatment of 184 patients with Parkinson’s disease. It is based on preoperative X-ray ventriculography imaging, intraoperative electrophysiological measurements and X-ray imaging, and postoperative neurological assessment. The atlas features a high resolution of 0.25 mm3 and a high accuracy of 0.25 mm. It is dynamic and can be rapidly recalculated for arbitrary resolution and extended by adding new patient data. The atlas can easily be reformatted and warped to match patient-specific data. Its applications include planning of subthalamic stimulations and neuroscience research to study functional properties of the STN. The presented method is general and can be applied for constructing human and animal probabilistic brain atlases.  相似文献   
44.
The aim of this paper is to present a case of a 59-year old patient diagnosed with a pituitary gland tumour. The psychiatric examination at the day of admission to the clinic suggested the manic episode was based upon the disseminated organic brain lesion. The patient presented mood elevation, carefree joviality, excitement, loss of social inhibition, inability to sustain attention. In course of the clinical observation and diagnostic progress the pituitary gland tumour was revealed and neurosurgical treatment was applied. The psychopathological course of the disorder was not typical for the established location. The psychopathological syndrome that was presented by the patient gave the global clinical impression of frontal and temporal lobes' dysfunction. This case report supports the present neurobiological opinions criticizing the direct relation of the location to the function within the central nervous system.  相似文献   
45.
OBJECTIVE: To identify potential geographic and temporal clustering of folate-sensitive fetal malformations as a prelude to a targeted preconception curriculum in folic acid supplementation. METHODS: Our comprehensive prenatal anomaly database was queried to select fetal malformations presumed to be sensitive to preconception folate insufficiency. Evidence of geographic clustering was evaluated by distribution of individual cases using zip codes of maternal residence. Potential temporal clustering of anomalies was sought by tabulating the frequency of each anomaly category during 5 consecutive 2-year intervals between 1992 and 2001. RESULTS: Over a 10-year period, approximately 2000 fetal anomalies were identified, of which 400 (20%) were considered potentially folate sensitive. We found geographic clustering of ventral wall defects as well as obstructive uropathy by zip code analysis. Significant increases in the frequencies of cardiac defects (P <.001) and obstructive uropathy (P <.001) were noted during the epoch of this study. A moderate increase in anomaly frequency was also seen in the diagnostic subcategory of gastroschisis, in which 15 of 27 total gastroschisis cases occurred in 2000-2001. CONCLUSIONS: Geographic clustering and temporal trends in anomaly rates were noted in certain folate-sensitive malformation categories. Identification of specific, high-incidence regions may provide an opportunity for targeted interventions designed to supplement the national folic acid campaign.  相似文献   
46.
Transcriptional profiling of medulloblastoma in children   总被引:3,自引:0,他引:3  
OBJECT: Although medulloblastoma is the most common malignant brain tumor found in children, little is known about its molecular pathogenesis. The authors have attempted to compare patterns of gene expression in medulloblastoma samples with those in the healthy cerebellum. METHODS: The authors used complementary (c)DNA microarray analysis to compare the expression of genes in samples of medulloblastoma and normal cerebellum. The expression levels of a subset of genes were then verified by immunohistochemical analysis. Six genes were identified that were expressed at a much higher level in at least five of six medulloblastomas: ezrin, cyclin D2, high mobility group protein 2, MAPRE1, histone deacetylase 2, and ornithine decarboxylase 1. A number of potentially important genes whose expression was much lower in medulloblastomas than in control cerebellum were also identified: tenascin R, TRK-B, FGF receptor, and death receptor 3. The expression levels of a subset of the identified genes were confirmed by immunohistochemical analysis, which was performed on fetal cerebellum and medulloblastoma samples. CONCLUSIONS: The authors demonstrate that cDNA microarray analysis is an effective method of increasing understanding of the molecular biology of medulloblastomas found in children. A comparison between gene expression patterns in medulloblastoma and those observed in healthy cerebellum may provide clues as to the origin of these tumors and may lead to the identification of new genes or pathways to be targeted for future therapies.  相似文献   
47.
INTRODUCTION AND OBJECTIVE: In 1983, the launch of cyclosporin was a significant clinical advance for organ transplant recipients. Subsequent drug research led to further advances with the introduction of cyclosporin microemulsion (cyclosporin ME) and tacrolimus. This paper presents the results from a long-term model comparing the clinical and economic outcomes associated with cyclosporin ME and tacrolimus immunosuppression for the prevention of graft rejection following renal transplantation. STUDY DESIGN: A model was developed to project the costs and outcomes over a 10-year period following transplantation. The model was based on the results of a prospective, randomised study of 179 renal transplantation recipients receiving either cyclosporin ME or tacrolimus, which was conducted by the Welsh Transplantation Research Group (median follow-up: 2.7 years). METHODS: The short-term costs and outcomes were the averages from the actual head-to-head trial data. From this, the long-term costs and outcomes were extrapolated based on the rate of change in patient and graft survival at 3, 5 and 10 years post transplant, as reported in the 1995 United Kingdom Transplant Support Service Authority Renal Transplant Audit. PERSPECTIVE AND YEAR OF COST DATA: The analysis was conducted from the perspective of a UK transplant unit. Costs were at 1999 prices (pounds sterling 1 = dollars US 1.42 = Euro 1.5) and costs and outcomes were discounted at 6% and 1.5%, respectively. RESULTS: The model estimated that 10 years after transplantation, the proportion of patients surviving was 56% of the cyclosporin ME cohort and 64% of the tacrolimus cohort. The cumulative cost of maintenance therapy at 10 years was pounds sterling 23204 per patient maintained on cyclosporin ME versus pounds sterling 23803 per patient on tacrolimus. The cost per survivor at 10 years was pounds sterling 37000 (tacrolimus) versus pounds sterling 41000 (cyclosporin ME) and the cost per patient with a functioning graft was pounds sterling 39000 versus pounds sterling 45000. A Monte Carlo simulation of the model (10000 simulations) gave an average cost at 10 years of pounds sterling 23279 (SD pounds sterling 3457) for cyclosporin ME and pounds sterling 22841 (SD pounds sterling 3590) for tacrolimus. A (second order) probabilistic sensitivity analysis was also performed. The average cost at 10 years from a simulated cohort of 1000 was pounds sterling 23473 (SD pounds sterling 2154) for cyclosporin ME and pounds sterling 24087 (SD pounds sterling 2025) for tacrolimus. CONCLUSION: Renal transplant recipients maintained on tacrolimus have better short- and long-term outcomes than patients maintained on cyclosporin ME. The long-term use of tacrolimus is a more cost-effective solution in terms of the number of survivors, patients with a functioning graft and rejection-free patients.  相似文献   
48.
Between 1999-2001 there were 6 patients with acute hepatitis B, previously vaccinated according to the recommended schedule of anti-hepatitis B immunization for adults, hospitalized in the Department of Infectious Diseases (Bytom, Silesian University Medical School). The study presents epidemiological and clinical analysis of these cases. Special attention is paid to possibility of immune response failure in spite of anti-hepatitis B vaccination. It is emphasized, that efficiency of active hepatitis B prophylaxis should be verified by estimation of serum anti-HBs antibodies, especially in patients with planned surgery.  相似文献   
49.
Ototoxicity of styrene and the synergistic action of styrene and noise have been shown in rats. The respective data in humans are scarce and equivocal. This study evaluated the effects of occupational exposure to styrene and combined exposures to styrene and noise on hearing. The study group, comprised of 290-yacht yard and plastic factory workers, was exposed to a mixture of organic solvents, having styrene as its main compound. The reference group, totaling 223 subjects, included (1) white-collar workers, exposed neither to solvents nor noise and (2) metal factory workers, exposed exclusively to noise. All subjects were assessed by means of a detailed questionnaire and underwent otorhinolaryngological and audiometric examinations. Multiple logistic regression analysis revealed almost a 4-fold (or 3.9; 95% CI = 2.4-6.2) increase in the odds of developing hearing loss related to styrene exposure. The factors adjusted for were: age, gender, current occupational exposure to noise, and exposure to noise in the past. In cases of the combined exposures to styrene and noise, the odds ratios were two to three times higher than the respective values for styrene-only and noise-only exposed subjects. The mean hearing thresholds--adjusted for age, gender, and exposure to noise--were significantly higher in the solvent-exposed group than in the unexposed reference group at all frequencies tested. A positive linear relationship existed between an averaged working life exposure to styrene concentration and a hearing threshold at the frequencies of 6 and 8 kHz. This study provides the epidemiological evidence that occupational exposure to styrene is related to an increased risk of hearing loss. Combined exposures to noise and styrene seem to be more ototoxic than exposure to noise alone.  相似文献   
50.
Quercetin is a naturally occurring flavonoid that exerts multiple pharmacological effects. In our previous study, we showed that quercetin greatly affects the lipid membrane. In this report, a study of quercetin on human erythrocyte membrane has been performed to determine the influence of this flavonoid on the fluidity and the conformational changes of membrane proteins. An additional aim of the study was to find how quercetin presence affects the resistance of membrane to haemolytic agents. The results showed that incorporation of quercetin into the erythrocyte membranes caused the changes of the partition coefficient of the Tempo spin label between the water and polar head group phases. In the studies, the W/S ratio has been used as a monitor of changes in protein conformation and in the environment within the membrane. It was observed that quercetin caused an increase in protein-protein interactions in human erythrocyte membranes. Haemolytic action of quercetin in the dark was also investigated. This compound showed protective effect against hypotonic haemolysis. However, in the heat-induced haemolysis quercetin caused acceleration of haemolysis. Dark reaction of erythrocyte with quercetin resulted in a shrinkage of the cells and alteration of their shapes. From the results we have concluded that modification of erythrocyte membrane by quercetin proceeds via reaction with membrane lipids and proteins.  相似文献   
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