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11.
Anti-IgE- and Con A-induced histamine release from serosal mast cells were compared to each other and to total serum levels of IgE in non-immunized, alum-injected, and Silica gel-injected rats of the BN, Fischer, PVG, and SD strains. The results indicate that the degree of anti-IgE-and Con A-induced release is strain-dependent and varies with immunization conditions. Furthermore, there is a gross but not complete correlation between the degree of serosal mast cell histamine release induced by the two secretagogues. However, Con A- or anti-IgE-induced release could significantly be correlated to serum levels of total IgE only in the Fischer strain but not in the BN or the PVG strains. In the SD strain, Con A-induced release correlated to serum IgE levels in Silica gel-injected but not in alum-injected animals.Subsidiary of AB Astra, Sweden.  相似文献   
12.
 Peptide YY (PYY) release in anaesthetized rats was studied during the 2 h following the intraduodenal administration of a semi-liquid meal of 21 kJ. Surgical and pharmacological manipulations were performed in order to analyse the mechanisms of PYY release. Postprandial PYY release was suppressed or strongly decreased by caecocolonectomy, truncal vagotomy, tetrodotoxin, hexamethonium, sensory denervation by perivagal capsaicin, and by the NO-synthase inhibitor L-N-arginine methyl ester, while atropine, adrenergic blockers, antagonists of type-A or type-B cholecystokinin (CCK) receptors or bombesin receptors had no effect. Comparing the digestive transit of the semi-liquid meal with the amount of PYY contained in the small bowel wall showed that nutrients had not reached the area rich in cells containing PYY by 30 min, the time at which there was a large PYY release in plasma. By 120 min, the meal front had travelled 72% of the small intestine length, just beginning to reach the PYY-rich part of the ileum. We conclude that the main postprandial PYY release studied in this model comes from ileal and colonic L-cells indirectly stimulated through a neural mechanism originating in the proximal gut and involving sensory vagal fibres, nicotinic synapses and NO release, while CCK and bombesin do not seem to be physiologically involved. Received: 17 July 1996 / Received after revision: 11 October 1996 / Accepted: 18 October 1996  相似文献   
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Nine healthy endurance-trained males were recruited to examine the effect of a dual dopamine/noradrenaline reuptake inhibitor on performance, thermoregulation and the hormonal responses to exercise. Subjects performed four trials, ingesting either a placebo (pla) or 2 × 300 mg bupropion (bup), prior to exercise in temperate (18°C) or warm (30°C) conditions. Trials consisted of 60 min cycle exercise at 55% W max immediately followed by a time trial (TT). TT performance in the heat was significantly improved by bupropion (pla: 39.8 ± 3.9 min, bup: 36.4 ± 5.7 min; P = 0.046), but no difference between treatments was apparent in temperate conditions (pla: 30.6 ± 2.2 min, bup: 30.6 ± 1.9 min; P = 0.954). While TT power output was consistently lower in the heat when compared to temperate conditions, this decrement was attenuated by bupropion. At the end of the TT in the heat, both core temperature (pla 39.7 ± 0.3°C, bup 40.0 ± 0.3°C; P = 0.017) and HR (pla 178 ± 7 beats min−1, bup 183 ± 12 beats min−1; P = 0.039), were higher in the bupropion trial than in the placebo. Circulating pituitary and adrenal hormone concentrations increased throughout exercise in all trials. Circulating serum prolactin was elevated above temperate levels during exercise in a warm environment ( P < 0.001). These data indicate that performance in warm conditions is enhanced by acute administration of a dual dopamine/noradrenaline reuptake inhibitor. No such effect was apparent under temperate conditions. It appears that bupropion enabled subjects to maintain a greater TT power output in the heat with the same perception of effort and thermal stress reported during the placebo trial, despite the attainment of a higher core temperature.  相似文献   
14.
BACKGROUND: Endometriosis and possible rectal involvement are difficult to assess by physical examination. Previous studies have shown the diagnostic value of magnetic resonance imaging and rectal endoscopic sonography (RES) in this setting, but not that of transvaginal sonography (TVS). The aims of this study were to compare the accuracy of TVS and RES for the diagnosis of pelvic endometriosis, and to compare the results with histological findings. PATIENTS AND METHODS: In a prospective study, 30 consecutive patients referred with clinical signs of endometriosis underwent TVS and RES; the images were interpreted blindly with regard to physical findings. RESULTS: Endometriosis was confirmed histologically in 28 (93%) of the 30 patients. Endometriomas were also present in 67% of cases. For the diagnosis of uterosacral endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 75 and 75%, 83 and 67, 95 and 90%, and 45 and 40% respectively. For the diagnosis of rectosigmoid endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 95 and 82%, 100 and 88%, 100 and 95%, and 89 and 64% respectively. CONCLUSION: Despite the large proportion of our patients who had intestinal endometriosis, representing a possible source of bias, our results suggest that TVS is as efficient as RES for detecting posterior pelvic endometriosis and should therefore be used as the first-line examination.  相似文献   
15.
Identification and characterization of human pulmonary dendritic cells   总被引:9,自引:0,他引:9  
Dendritic cells (DC) are specialized antigen-presenting cells, linking innate and adaptive immune responses, and thus play an important role in immunologically mediated diseases, including pulmonary diseases such as asthma and respiratory viral infections. Although much is known about the characteristics of lung DC in animal models, very few data concerning human lung DC are available. The goal of our study was to identify and characterize dendritic cells in human lung by preparing single-cell suspensions from surgical resection specimens and subsequent labeling with the recently developed blood dendritic cell antigen (BDCA) markers. A straightforward isolation procedure was developed to avoid phenotypical and functional changes induced by extensive purification methods. In this way, human lung DC were directly identified without the need for an additional adherence step for further purification. For the first time, we demonstrate the presence of three previously unidentified DC subsets in human lung digests: myeloid DC type 1 (BDCA1+/HLA-DR+), myeloid DC type 2 (BDCA3+/HLA-DR+), and plasmacytoid DC (BDCA2+/CD123+). The presence of CD1a+ DC in the human lung was confirmed. The identification and characterization of different human pulmonary DC subtypes is of great importance for the future development of DC-based immunotherapies.  相似文献   
16.
BackgroundDiffuse large B-cell lymphoma (DLBCL) is the most common subtype of non–Hodgkin lymphoma in the posttransplant setting. Treatment is based on chemotherapy; surgery is still debated and should be performed in very select cases.MethodsWe observed 2 patients out of 300 who underwent lung transplantation in the Nouvel Hopital Civil between 2013 and 2019 with primary hepatic lymphoma. Chemotherapy with a rituximab-cyclophosphamide, hydroxydaunorubicin, vincristine, prednisone protocol was performed in all patients. Mycophenolate mofetil was interrupted before treatment, and everolimus was introduced after chemotherapy by associating tacrolimus withdrawal.ResultsOne patient showed complete remission; after 7 years, no recurrence has been noticed. The second is still undergoing chemotherapy with no signs of disease progression.ConclusionsDLBCL risk is higher in solid organ transplant recipients than in the general population. Primary hepatic lymphoma diagnosis is often difficult and based on histologic findings after initial clinical and radiological suspicion of primary or secondary liver neoplasia. Diagnosis is challenging because no clinical, radiological, or biological features exist. Biopsy is always indicated for histologic confirmation. Chemotherapy is the mainstay of therapy, but surgery may be indicated in very select patients.  相似文献   
17.
BACKGROUND: An array of biological features related to tumor cell differentiation status, growth rate, and invasive potential have been identified as potential prognostic factors in breast cancer. We were interested in determining their relative importance in predicting patient survival. PURPOSE: We evaluated the relative weight of the following four biological factors in predicting survival of patients with breast cancer: tumor cell DNA content (determined by flow cytometry), tumor cell proliferation rate (determined by thymidine kinase activity), expression levels of cathepsin D and urokinase plasminogen activator, and several "classical" clinical and histological factors. METHODS: Selected from a prospectively updated database, the study population consisted of 319 primary breast cancer patients who received treatment and follow-up care (median, 6 years) in the Centre René Huguenin. To determine the profile of biological factors for each patient, we used frozen tumor specimens and (except for the flow cytometric DNA content assay) commercially available assay kits. We determined by Cox multivariate analysis the relationships of the biological factors to each other, to classical prognostic factors, and to disease-free and metastasis-free survival. RESULTS: In the overall population, disease-free survival was best predicted by node status (P = .004), clinical tumor size (P = .02), and cathepsin D expression (P = .01), whereas metastasis-free survival was best predicted by node status (P = .0004), clinical tumor size (P = .009), and urokinase plasminogen activator expression (P = .04). In node-negative patients, thymidine kinase activity was the only factor selected for disease-free (P = .04) and metastasis-free (P = .05) survival. In node-positive patients, the number of positive axillary lymph nodes was the only factor selected for disease-free (P = .0008) and metastasis-free (P = .00017) survival. CONCLUSIONS: Our retrospective analysis has identified protease expression and tumor cell proliferation rate as important biological prognostic factors in breast cancer. Prospective clinical trials should be undertaken to confirm these results.  相似文献   
18.
OBJECTIVE: Fever is a common cause of children visits to emergency units. Clinical evaluation does not always eliminate a bacterial infection. Among blood markers, several publications showed the interest of CRP. This study was undertaken to evaluate correlation between two techniques of CRP, one by usual technique at the laboratory and the other by a rapid test, and to evaluate the impact of this rapid test for febrile children at the emergency room, when a hospitalization was not immediately decided. MATERIAL AND METHODS: The study was undertaken in 2004-2005 in eight emergency paediatric units in Ile-de-France concerning febrile children during two periods. In period A, children had at the same time a CRP dosage through two methods, whereas in period B, only a rapid CRP test was first managed. The test used was NycoCard CRP Single test (Progen Biotechnique). RESULTS: Between September 2004 and June 2005, 572 children were included, 268 in period A and 304 in period B. Comparison of CRP results by the two methods showed for 247 children (93%) a fairly good linear correlation (r: 0.929). Blood cell count was the most often prescribed test (99.4 vs 10.5%). Conversely to chest radiography, blood culture, fibrinogen and urinary test were significantly most frequent in period A. The average cost of the additional examinations was 2.6 times more important during the first period. Duration of children management in the units was approximately two times shorter when rapid CRP test was used (199.7+/-92.8 vs 103.5+/-98.6 min). CONCLUSION: This study shows the interest of rapid CRP test for febrile children in the emergency units, and has to be confirmed in ambulatory paediatric practice.  相似文献   
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