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11.
Medpor implants were placed on the periosteum of the mandible in infant rabbits to study their effects on growth. Three months later radiological and histopathological studies were performed in situ and after removal of the mandible. The authors demonstrate that implants did not affect normal development of the mandible; however, there was a decrease in bone thickness and a mononuclear cell reaction was caused where the implant came in contact with the bone.  相似文献   
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Objectives: To investigate the correlation of nuclear p53 accumulation with disease outcome in a cohort of patients with transitional cell carcinoma of the bladder. Methods: A total of 90 patients (11 female, 79 male) with transitional cell carcinoma of the bladder were included in this study. Tumour samples from the primary tumour were analysed by immunohistochemistry for nuclear accumulation of p53 protein. Outcome of each patient was recorded and investigated for a possible relation with p53 status. Results: Nuclear p53 deposition was determined in 22 specimens. The nuclear p53 deposition was seen in less than 20% of the nuclei examined in 13 and more than 20% in 9 cases. No stromal staining was observed. Nuclear p53 deposition was present in 15.2% (7/46) of grade 2 tumours, and 34% (15/44) of grade 3 tumours (p=0.037). Stage distribution revealed 15.5% (5/33) positivity in stage pTa, 25.8% (8/31) in pT1 and 34% (9/26) in stage pT2–3 tumours. Tumours with p53 nuclear accumulation had a higher rate of recurrence and progression and shorter survival. Conclusion: Results of the current study indicate p53 as an important factor in determination of biological behaviour of bladder cancer.  相似文献   
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Purpose: Our purpose was to determine the feasibility and efficacy of performing testicular or epididymal sperm retrieval prior to the injection of human chorionic gonadotropin (hCG). Methods: This report deals with 87 sperm-positive percutaneous epididymal sperm aspiration (PESA), percutaneous testicular sperm aspiration (PTSA), or testicular sperm extraction (TESE) cycles. All sperm retrieval procedures were performed prior to administration of hCG to the women. Retrieved spermatozoa were cultured in vitro in simple medium for approximately 40 hr prior to intracyto-plasmic sperm injection. Results: In all but one cycle in which TESE was performed for nonobstructive azoospermia, motile sperm were available for ICSI. The overall fertilization rate was 53%. Pregnancy rate per transfer and implantation rate per embryo were 41.2 and 15.7%, respectively. Conclusions: Satisfactory fertilization and pregnancy rates can be achieved when PESA, PTSA, or TESE is performed prior to the injection of hCG followed by in vitro culture of spermatozoa approximately 40 hr before ICSI. Scheduling of testicular or epididymal sperm retrieval cases in this way appears to ease the workload on laboratory and operating room personnel. Furthermore, withholding hCG when sperm is absent may obviate the unnecessary risk of ovarian hyperstimulation when spermatozoa cannot be retrieved.  相似文献   
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Thirty-five patients with unilateral or bilateral neglected congenital dislocation of the hip (CDH) were treated with subtrochanteric valgus-extension osteotomy between 1975 and 1992. There were 29 females and 6 males in the group. A total of 50 osteotomies was performed. The mean age of the patients was 22 years; the mean follow-up was 7 years. Before operation, the main complaints were pain and gait abnormalities. Leg-length discrepancy was another problem, especially for unilateral cases. The main indication for the operation was pain. This pelvic support osteotomy was performed to correct the instability of the hip and as a result of this to relieve pain. Patients were retrospectively evaluated based upon Harris Hip Score and self-evaluation. The mean Harris Hip Score was 49 before operation and improved to 72 after the operation. Alleviation of the pain was the most significant functional outcome of the treatment. It was also noted that limping could be improved if an adequate rehabilitation program was followed. We conclude that in neglected CDH cases with pain, limping and lumbar hyperlordosis in the young adult, a subtrochanteric valgus-extension osteotomy can give satisfactory results.  相似文献   
15.
PURPOSE: Accurately estimating transition zone volume is important for the medical or surgical management of symptomatic benign prostatic hyperplasia and determination of prostate specific antigen density of the transition zone. We evaluated whether preoperative transrectal ultrasound measurements of the transition zone predict enucleated adenoma weight. MATERIALS AND METHODS: We measured transition zone volume preoperatively using transrectal ultrasound and the prolate ellipsoid method in 50 patients with presumed benign prostatic hyperplasia who underwent suprapubic prostatectomy. Transition zone volume corresponds to the adenoma. Enucleated adenoma weight was then correlated with preoperatively determined transition zone volume. RESULTS: As measured by transrectal ultrasound, mean transition zone volume plus or minus standard deviation was 80.88 +/- 37.42 cc (range 31 to 200). Mean enucleated adenoma weight was 68.70 +/- 36.26 gm. (range 18 to 180). There was a statistically significant correlation of estimated transrectal ultrasound volume of the transition zone with enucleated prostate adenoma weight (r = 0.95, p <0.001). However, when prostate adenoma weight was determined using the formula, prostate adenoma weight = -6.00 + 0.92 x transition zone volume, we noted a significant difference in mean prostate adenoma weight and mean transition zone volume (p <0.001). Since the regression coefficient of transition zone volume was significantly different from 1, we identified no agreement of prostate adenoma weight with estimated transrectal ultrasound volume of the transition zone. CONCLUSIONS: These data reveal a significant difference in mean prostatic adenoma weight and mean transition zone volume. Although transition zone volume measurements are well described, clear agreements on such measurements should be obtained to determine transition zone volume more precisely.  相似文献   
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汪南华  王锐  冷宗康  彭司勋 《药学学报》1990,25(12):920-925
缩氨基硫脲类化合物有抗肿瘤、抗病毒和抗菌等多种药理活性。Barret等首次报道了乙二醛二缩氨基硫脲(Ⅰ)的抗疟活性。Klayman等研究了缩  相似文献   
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Background and Aim:  The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia–reperfusion (I/R).
Methods:  Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results:  The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P  < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P  < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P  < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions:  The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models.  相似文献   
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