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241.
A retrospective study was carried out on 48 patients to correlate preoperative ultrasound findings with postoperative histopathology findings and to assess the sensitivity, specificity, positive predictive values, and negative predictive values of ultrasound in the diagnosis of Morton's interdigital neuroma. All case sheets of 48 patients operated on between 1997 and 2005 were reviewed in the medical record section of Ninewells Hospital, Dundee, Scotland, so that preoperative ultrasound reports were compared with the postoperative histopathological reports. A statistical analysis of the results was performed. Ultrasonography showed 43 true-positive cases, 1 true-negative case, and 4 false-negative cases out of 48 cases. Histopathology showed 47 true-positive cases and 1 true-negative case; statistical analysis performed on the results showed a sensitivity of 91.48%, a specificity of 100%, and 100% positive and 20% negative predictive values, respectively. In our analysis, the probability that ultrasound will confirm the presence of plantar intermetatarsal neuroma is 91.67%.  相似文献   
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The applicability of a hapten-antihapten sandwich technique incorporating a monoclonal antihapten bridge antibody to localisation of tissue antigen is described. The results show that the method is both versatile and selective and has the potential of being even more sensitive than currently used immunoperoxidase methods.  相似文献   
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Activity in the mammalian thalamocortical system is often accompanied by a synchronous discharge of cortical and thalamic neurons. Although many functions have been attributed to such synchronous firing, it is not known whether or how synchrony of firing per se affects thalamocortical operations. Direct experimental tests of the consequences of neuronal synchronization in vivo are hard to carry out, whereas theoretical studies based on single-neuron models cannot reveal the effects of synchrony at the system level. To overcome these limitations, we have used a perturbational approach to test the causal efficacy of synchrony per se in large-scale simulations of the thalamocortical system. The test consists of selectively disrupting firing synchrony by 'jittering' the timing of action potentials in the simulations and determining whether firing rates are modified by this perturbation. The simulations are based in detail on the known anatomy and physiology of the thalamocortical-visual system of the cat, and have been shown in a companion paper to produce episodes of fast synchronous activity at multiple levels. By carrying out the perturbation analysis, we established that neurons can have long membrane time constants (8-16 ms) and balanced synaptic activations, and yet function collectively in such a way that synchrony within a time window of 4 ms significantly affects the rates and selectivity of the responses to visual stimuli. The simulations also revealed a complex interplay, at the network level, between synchrony of firing and rate of firing. The dynamic consequences of firing synchrony were most evident when spike jittering was applied to specific polysynaptic loops involving corticocortical and corticothalamic connections. These results support the view that firing synchrony within thalamocortical and corticocortical loops plays a causal role in the cooperative and competitive neural interactions that produce pattern-selective responses in the cortex.   相似文献   
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Of the first 350 bases upstream of the ATG signal sequences were obtained representing the following HLA-A locus alleles: A*01, A*0102, A*02, A*0202, A*0206, A*0207, A*03, A*0302, A11.2, A11.1, A*68, A*68011, A*30, A*3002, A*23, A*24, A*26, A*2602, A*25, A*29, A*2902, A*31, A*31011, A*32, A*3201, A*33, A*3301, A*3303, A*34, A*6601, A*6602 A*74, A*80. We found 21 polymorphic positions of which a surprisingly large number (altogether 9) represent allele specific exchanges. For all 35 alleles tested of the HLA-A locus we found 16 different types of promoter. While all tested A2 subtypes, A*0201, A*0202, A*0206, A*0207 share the same promoter, there were in contrast several situations in which different subtypes of the same group have different promoters. This is true for HLA A*01, A*0102; A*03, A*0302; A*30, A*3002; A*6601, A*6602; A*32, A*3201; A*29, A*2902. Looking at the binding sites for nuclear factors, we observe that TATA-box, CAT-box, Enhancer B, the interferon response sequence and the Enhancer A (except HLA-A30 has one base exchange) are conserved within the HLA-A locus. The interferon response sequence shows for all A-locus alleles a double base pair exchange (TT for AC). In comparison with the promoter polymorphism of the HLA-B locus (Yao et al., 1995) we find a surprising diversity of the promoters in the HLA-A locus. While for the B-locus promoters large groups of sometimes strongly different alleles share the same promoter, in the HLA-A locus there is a private promoter for almost each allele and sometimes even each subtype. This lead to the conclusion that the promoter polymorphisms of the HLA-A and the HLA-B locus have been subjected to different selection pressure in evolution.  相似文献   
248.
Epididymal sperm aspiration and in-vitro fertilization (IVF) with intracytoplasmic sperm injection is an established treatment for obstructive azoospermia. Sperm aspiration is performed with either an incision or percutaneously. To control costs, minimize morbidity and retain the advantages of both approaches, we developed a mini-incision technique for epididymal aspiration and here report sperm retrieval and procedure-related outcomes. Twenty-six consecutive patients with obstructive azoospermia underwent epididymal sperm retrieval through a 1 cm incision with local anaesthesia to provide spermatozoa for concurrent IVF cycles. The quality of retrieved spermatozoa, the quantity of spermatozoa cryopreserved as well as anaesthetic requirement, recovery time and patient satisfaction were evaluated. Fresh epididymal spermatozoa were retrieved in 25 of 26 (96%) patients. In one patient, testicular sperm extraction was necessary. Excess motile spermatozoa were cryopreserved in 24 of 26 (92%) patients; a mean total motile count of 4.8x10(6) motile spermatozoa were banked. The procedure was performed with 62% of patients receiving minimal i.v. sedation. Post-procedure recovery was rapid, with a median time to return to work of 2.0 days with a median of 2.0 pain pills taken. Procedure-related satisfaction was high. The mini-micro-epididymal sperm aspiration achieves the goals of reliable retrieval of abundant epididymal spermatozoa with a single, minimally morbid procedure. It appears to combine the advantages of the incision and percutaneous approaches.   相似文献   
249.
BACKGROUND: For the diagnosis of asthma in young children, GPs have to rely on history taking and physical examination, as spirometry is not possible. The additional diagnostic value of specific immunoglobulin E (IgE) to inhalent allergens remains unclear. AIM: To assess the predictive accuracy of specific IgE to cat, dog, and/or house dust mites in young children for the subsequent development of asthma at the age of 6 years. DESIGN OF STUDY: Prospective follow-up study. SETTING: Seventy-two general practices. METHOD: A total of 654 children, aged 1-4 years, visiting their GPs for persistent coughing (>/= 5 days), were tested for IgE antibodies by radio allergosorbent testing (RAST). Parents completed a questionnaire on potential risk indicators. Those children who showed an IgE-positive status (12.7%) and a random sample of those with an IgE-negative status (<0.5 U/ml) were followed up to the age of 6 years when the asthma status was established. The main outcome measure was asthma at the age of 6 years (combination of both symptoms and/or use of asthma medication, and impaired lung function). RESULTS: Addition of RAST results to a prediction model based on age, wheeze, and family history of pollen allergy increased the area under the receiver operating characteristic (ROC) curve from 0.76 to 0.87. Furthermore, RAST improved patient differentiation as indicated by a change in the range of asthma probabilities from 6-75% before the IgE test, to 1-95% after the IgE-test. CONCLUSION: Sensitisation to inhalant allergens in 1-4-year-olds, as shown by RAST, is a useful diagnostic indicator for the presence of asthma at the age of 6 years, even after a clinical history has been obtained. This model should preferably be validated in a new population before it can be applied in practice.  相似文献   
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PURPOSE: The cellular and molecular mechanisms that regulate the organization of bladder urothelium into basal, intermediate and superficial cell layers remain poorly understood. We tested the hypothesis that fibroblast growth factor (FGF)-7 is essential for generating a multilayered stratified bladder epithelium. MATERIALS AND METHODS: The morphological and molecular characteristics of bladder urothelium in age and sex matched FGF-7 +/+ wild-type and -/- null mice were evaluated. In addition, the effect of exogenous FGF-7 on the growth and differentiation of primary murine urothelial cells was assessed. RESULTS: Morphometric analyses demonstrate that FGF-7 null urothelium is markedly thinned compared with wild-type urothelium. Electron microscopy revealed that null urothelium lacks the intermediate cell layers and molecular marker analyses confirmed this observation. In vitro cell culture experiments indicated that FGF-7 regulates urothelial cell growth, differentiation and stratification. Primary urothelial cultures maintained without FGF-7 ceased to divide and expressed proteins characteristic of terminally differentiated umbrella cells. In contrast, cultures maintained with exogenous FGF-7 contained proliferating epithelial cells with protein expression patterns consistent with those of intermediate cells in addition to terminally differentiated, post-mitotic umbrella cells. Importantly, isolated urothelial cells maintained with exogenous FGF-7 formed a multilayered epithelium in vitro. CONCLUSIONS: Collectively these data indicate that FGF-7 is essential for normal bladder urothelial stratification, specifically the formation of the intermediate cell layers. Fibroblast growth factor-7 stimulates urothelial proliferation and delays the differentiation of these cells into post-mitotic umbrella cells.  相似文献   
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