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91.
Pulmonary inflammatory pseudotumor is rare. A 34-year-old woman visited our hospital due to an abnormal chest shadow. Computed tomograhy showed a nodule in the right upper lobe. Bronchoscopy showed a polypoid endobronchial nodule obstructing most of the orifice of B2a. The nodule was white, glossy, and smooth, and it seemed to be covered with bronchial mucosa. However, transbronchial biopsy could not facilitate a diagnosis. To obtain a definitive diagnosis, we performed lobectomy of the right upper lobe using video-assisted thoracic surgery and removed the nodule completely. The pathologic diagnosis made during surgery was inflammatory pseudotumor. Immunohistochemical examination showed proliferating spindle cells were positive for vimentin and smooth muscle actin, but negative for epithelial markers. These findings were consistent with the staining pattern of inflammatory pseudotumor previously reported. Careful follow-up is necessary to detect any sign of local recurrence and distant metastases.  相似文献   
92.
Background and Aim: Little is known about the efficacy and safety of infliximab for ulcerative colitis refractory to tacrolimus. The aim of this study was to evaluate the efficacy and safety of infliximab in the induction of remission in ulcerative colitis patients with persistent symptoms despite tacrolimus therapy. Methods: We report a retrospective, observational, single‐center case series of 12 consecutively enrolled patients with ulcerative colitis refractory to tacrolimus that received infliximab therapy for the induction of remission. Eight patients received a single infusion of infliximab, and four received two or more infusions. Median follow‐up duration was 16.0 months (range, 1.6–41.4 months). The clinical response was evaluated based on a modified Truelove‐Witts severity index. Results: Six patients (50.0%) achieved clinical remission within 30 days. Overall cumulative colectomy‐free survival was estimated to be 58.3% at 41.4 months. Adverse events included an elevation of liver enzymes (1/12; 8.3%) and a mild infusion reaction (1/12; 8.3%). No mortality occurred. Conclusions: Infliximab can induce remission in patients with ulcerative colitis who do not tolerate or respond to tacrolimus therapy.  相似文献   
93.

Background  

This study investigated issues related to initial stability after stem fixation. Finite element models of the AI-Hip cementless stem were constructed for computer simulation.  相似文献   
94.
Prostaglandins and thromboxanes are important modulators of airway physiology. The synthesis of these mediators depends on two isoforms of cyclooxygenase (COX), constitutive COX-1 and inducible COX-2. COX-2 expression has been observed in various inflammatory diseases, but not all aspects of the expression and the role of COX-2 in conditions of allergic inflammation such as asthma are clear. In the present study, we examined the 72-h kinetics of the expression of COX-isoform mRNA in ovalbumin-sensitized and -challenged guinea-pig lungs. The sensitized animals showed a robust and transient induction of COX-2 mRNA expression within 1 h after ovalbumin challenge, whereas their COX-1 mRNA levels remained unchanged. Upregulation of the level and activity of COX-2 protein followed the induction of COX-2 mRNA. Lung slices harvested from ovalbumin-challenged animals released more prostaglandin D(2) and prostaglandin E(2) spontaneously or in response to A23187 (10 microM) ex vivo than did those from unchallenged animals. This response was significantly blocked by the COX-2 selective inhibitors, NS-398 and JTE-522. In vivo administration of NS-398 significantly inhibited the accumulation of eosinophils and neutrophils in the lungs. In conclusion, de novo COX-2 expression during allergic inflammation modifies prostanoid synthesis in the lung and airway pathophysiology.  相似文献   
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Background: The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments.

Methods: This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension.

Results: Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = ?0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p < 0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022).

Conclusion: Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.  相似文献   

98.
Primary lymphoma of the gallbladder is an exceedingly rare disease. We experienced an asymptomatic case of primary non-Hodgkin’s lymphoma of the gallbladder in a 55-year-old woman in whom laparoscopic cholecystectomy made a definite diagnosis. Abdominal computed tomography revealed a 4-cm gallbladder tumor with markedly enlarged lymph nodes in the retropancreatic area. Despite the marked involvement of lymph nodes, serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 were not elevated. The discrepancy between the imaging findings and the patient’s mild clinical presentation led us to suspect that the tumor was a lymphoma. We examined serum markers of lymphoma, revealing slight elevations of interleukin (IL)-2 receptor and thymidine kinase. Laparoscopic cholecystectomy for a total biopsy was performed successfully, and the results of intraoperative frozen-section examination led us to have a high suspicion of malignant lymphoma. The final diagnosis was large diffuse B-cell lymphoma of the gallbladder with a positive CD20 antibody reaction. The patient received postoperative chemotherapy with R-CHOP (rituximab, 500 mg; cyclophosphamide, 1000 mg; adriamycin, 68 mg; vincristine, 1.9 mg; and prednisone, 80 mg) starting on postoperative day 12. She achieved complete remission and is still in complete remission 3 years and 2 months after the cholecystectomy. In conclusion, gallbladder lymphoma should be added to the differential diagnosis of gallbladder tumors, especially when the imaging findings and clinical presentation are not consistent with typical signs of gallbladder carcinoma, and laparoscopic cholecystectomy is helpful for the confirmation of suspicious cases.  相似文献   
99.
Background: We assessed the efficacy and anticarcinogenic effects of interferon (IFN) therapy in patients with hepatitis C virus (HCV)-related cirrhosis. Methods: The study subjects were 123 Japanese patients with HCV-related cirrhosis with genotype 1b low viral load or genotype 2 who received IFN from 1989 to 2005 (18 patients continue to receive IFN therapy). They included 81 men and 42 women aged 29-74 years (median, 56 years). Results: Univariate analysis identified four parameters that significantly influenced SVR; viral load (low HCV concentration, P < 0.001), duration of IFN therapy (>/= 52 weeks, P = 0.029), daily dose of IFN (>/= 6 million units, P = 0.018), induction therapy (presence, P = 0.010) and choline esterase (> 1.0 DeltapH, P = 0.037). Multivariate analysis identified viral load (risk ratio = 6.329, P < 0.001) and daily dose of IFN (risk ratio = 2.62, P = 0.042) as two independent parameters thatinfluenced SVR. During the observation period, newly developed hepatocellular carcinoma (HCC) was detected in 22 patients. The rates of development of HCC in patients with SVR were 5.8% at the fifth year and 10.3% at the 10th year, compared with 25.8% at the fifth year and 42.5% at the 10th year in non-SVR patients. Multivariate analysis showed that IFN efficacy (SVR) was the only independent factor of hepatocarcinogenesis (hazard ratio: 0.185, 95% confidence interval: 0.042-0.810, P = 0.025) Conclusion: Among patients with HCV-related cirrhosis, the rate of development of HCC is significantly less in patients with SVR.  相似文献   
100.
The Wnt signaling pathway has recently been demonstrated to play an important role in regulation of bone formation. LRP5 is thought to signal through the canonical Wnt pathway. In humans, LRP5 loss-of-function mutations lead to low bone mass with fractures, while LRP5 gain-of-function mutations lead to high bone mass, thus identifying LRP5 as an important regulator of bone mass. Patients with sclerosteosis have a severe skeletal disorder with progressive bone overgrowth due to a loss of function of the SOST gene, which implicates its role as a suppressor of bone formation. Recent study revealed that SOST is a BMP antagonist with unique ligand specificity, negatively regulating bone formation by repressing BMP-induced osteoblast differentiation or function or both.  相似文献   
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