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61.
Immunoprevention is a fresh approach to cancer prevention based on the stimulation of the immune system before tumor onset. Immunoprevention was effective in various models of carcinogen-induced or autochthonous tumor progression. Vaccines made of cells or DNA plasmids combined with appropriate adjuvants completely blocked mammary carcinogenesis in HER-2/neu transgenic mice. At variance with cancer immunotherapy, the mediators of immunoprevention are antibodies and T-cell-derived cytokines, rather than cytotoxic T-cells. Immunopreventive approaches and chemoprevention with tamoxifen or cyclooxygenase-2 inhibitors can be combined advantageously. The success obtained in preclinical studies suggests that cancer immunoprevention should progress to clinical testing.  相似文献   
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OBJECTIVES: This study investigated the relationship between traffic air pollution and asthma, using a case-control design applied to routinely collected data. METHODS: Subjects resident in Turin during the period 1997-1999 and admitted for asthma were defined as cases; patients admitted for causes other than respiratory diseases or heart diseases were defined as controls. Nitrogen dioxide and total suspended particulate were considered as indicators of traffic air pollution. Statistical analysis were performed, separately for young (0-14 years), adult (15-64 years) and elderly (>64 years) patients, with a logistic regression model; results are expressed as percentage of risk modification for a 10 g/m(3) increase in exposure to pollutants. RESULTS: The risk of emergency admissions for asthma rose significantly with increased exposure to nitrogen dioxide [2.4%, 95% Confidence Interval: 0.5%; 4.3%], and total suspended particulate [2.3%, 95% Confidence Interval: 1.1%-3.6%]. The significant association was evident, in particular, among young and elderly patients for both pollutants. CONCLUSION: Using a case-control design both easy to use and manage, the study confirms the significant association between hospital emergency admissions for asthma and exposure to nitrogen dioxide and total suspended particulate pollutants.  相似文献   
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Intracranial schwannomas, accounting for 8 to 10 % of all primary brain neoplasms, are relatively frequent intracranial tumors, but a "pure" intrasellar localization is exceptional. We report the case of an intra-suprasellar schwannoma mimicking a non-functioning pituitary macroadenoma both radiographically and clinically. A 73-year-old man presented with an episode of lipothymia followed by episodes of mental confusion. The neurological investigations revealed a bitemporal hemianopia and a hypopituitaric status. The neuroradiological investigations showed an intra-suprasellar mass resembling a pituitary adenoma. The patient underwent surgery performed by means of an endoscopic endonasal transsphenoidal approach, with a subtotal excision of the tumor. The histopathological studies revealed a cellular schwannoma. The review of the literature disclosed another 8 cases of intrasellar schwannomas. The possibility of an intrasellar schwannoma has to be considered in the differential diagnoses of neoplastic and non-neoplastic lesions of the sellar area.  相似文献   
65.
Role of cytokines in gonarthrosis and knee prosthesis aseptic loosening   总被引:4,自引:0,他引:4  
Cytokines, which have been demonstrated in synovial fluids during various joint diseases, play an important role in mediating synovial inflammation and in regulating the immune response of many inflammatory processes. We studied synovial fluid, serum, and synovial fragments obtained from 33 patients—10 affected by serious gonarthrosis re-quiring a prosthetic implant, 8 with knee prosthesis aseptic loosening, and (as controls) 15 affected by degenerative meniscopathies—to evaluate the degree of inflammation and level of interleukins (IL-2, IL-4, IL-6, IL-10) and interferon secretion. Histological analysis revealed slightly more infiltration by inflammatory cells in the synovial tissue of patients with gonarthrosis and knee prosthesis aseptic loosening than in that of the control group, with a high prevalence of macrophages. Moreover, we observed enhanced production of the studied cytokines, especially in synovial fluid as compared to serum, indicating that in the pathological conditions examined the inflammatory events are mainly localized. Because the role of these cytokines is to modulate inflammation, better knowledge of the involvement of cells and their soluble mediators in articular damage could guide immunomodulating treatment.  相似文献   
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BACKGROUND: A systemic reaction to mycobacteria biases the balance of T helper cell types 1 and 2 toward T helper cell type 1. BCG vaccination mimics some characteristics of mycobacterial infection. Children who have undergone tuberculin conversion after BCG vaccination seem to be more likely to lose their atopic symptoms. Inhibition of both allergic response and airway hyperreactivity after vaccination for mycobacteria has been observed in animal experiments. OBJECTIVE: To evaluate the effects that BCG vaccination has on the serological status of allergic people. PARTICIPANTS AND METHODS: This study included 20 volunteers with a history of allergic rhinitis who were required to undergo BCG vaccination by Italian law. Epicutaneous allergy testing with a panel of common seasonal and perennial inhalational allergens and 2 blood withdrawals were performed. The serum total IgE levels and the serum allergen-specific IgE levels of each individual were measured just before BCG vaccination and again 4 months later. Total IgE levels were determined using the paper radioimmunosorbent test, and allergen-specific IgE levels were determined using the radioallergosorbent test. RESULTS: Total IgE and allergen-specific IgE levels were significantly decreased after BCG vaccination (P =.004 and P<.001, respectively). CONCLUSION: BCG, an effective stimulus for cell-mediated immunity, deserves further study to evaluate its ability to modulate the immune response associated with allergic rhinitis.  相似文献   
69.
Many options of varying complexity are available for the management of congenital short digits resulting from aphalangia in symbrachydactyly and constriction ring syndrome. We have used non-vascularized free toe phalanx transfers for these children when a vascularized toe transfer has been contraindicated. We describe our technique and experience with 22 children who underwent a total of 64 transfers of the proximal (35) or middle (29) toe phalanges (average 3 per child). The mean age at initial surgery was 15 months, and the mean follow-up was 5 years. Duration of time until epiphyseal closure could not be determined accurately, but total digital elongation averaged 6mm. Complications of this technique include joint instability, premature epiphyseal closure and, in one patient, infection and graft loss. Donor site deformity was determined according to measured growth deficit and toe function. This technique is a simple option for digital elongation and, if performed in the appropriate age group in short fingered and monodactylous subtypes of symbrachydactyly, has the potential to allow growth and function with minimal donor site deficit.  相似文献   
70.
Background: Deaths due to alcohol consumption are an important component of all-cause mortality, particularly premature mortality. However, there are considerable regional variations, the reasons for which are unclear. Methods: Estimates were made as reliably as possibly using vital statistics and best estimates of risk of the alcohol-attributable mortality, by age, sex and cause for four European countries (England and Wales, Germany, Denmark and Italy). Twenty-seven alcohol-related conditions were considered including the possible cardio-protective effects of alcohol. Results: It was estimated that there are approximately 2% fewer deaths annually in England and Wales than would be expected in a non-drinking population and 0.3% fewer deaths among East German females. In West Germany, Denmark, Italy and among East German males there are more deaths caused by alcohol than are prevented (between 0.7 and 2.6% of all deaths). The highest age-specific proportion of alcohol-attributable deaths is found in East Germany where around 30% of deaths among males aged 25–44 years are due to drinking. Among young men in all four countries the largest contributor to alcohol-related deaths is road traffic accidents involving alcohol. Conclusions: Possible explanations for the variation in alcohol-attributable deaths between countries include different underlying heart disease rates, different patterns of alcohol consumption and beverage preferences, and different use of mortality classification. Differences in the reported alcohol consumption levels explain little of the variation in alcohol-attributable deaths. Estimating alcohol-attributable mortality by age and sex across countries may be a useful indicator for developing alcohol strategies and exploring ways of preventing premature mortality.  相似文献   
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