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41.
The Harmonic Scalpel (HS) is frequently used for hepatic resection. Yet, no current study addresses its utility compared to conventional methods. We reviewed our experience with this device to determine if it decreased perioperative complications when compared to the traditional clamp crushing technique. One hundred forty-nine anatomic hepatic resections were performed at our institution from September 1992 to February 2002. Patients were divided into two groups based on the technique of resection: HS [53% (n = 79)] versus clamp crushing [47% (n = 70)]. Use of the HS was associated with a shorter mean operative time (357 +/- 15.0 vs. 404 +/- 19.1 min; p = 0.05) and a trend toward decreased blood loss (1211 +/- 125.5 vs. 1411 +/- 180.7 mL; P = NS) and transfusion requirements (2.6 +/- 0.5 vs. 1.7 +/- 0.3 units; P = 0.10). However, use of the HS was associated with a significant increase in biliary fistulas [24% (n = 19) vs. 7% (n = 5); P = 0.01]. Use of the Harmonic Scalpel was associated with decreased operative time and a trend toward decreased blood loss and transfusion requirements. Its use was also associated with a significant increase in the incidence of postoperative bile leaks, and, therefore, surgeons must be vigilant during liver parenchymal transection when using this device.  相似文献   
42.
Investigation of the bypassed stomach in patients with suspected peptic ulcer disease presents a major challenge to bariatric surgeons. Various methods have been suggested for visualization of the duodenum and bypassed stomach. These include endoscopy via percutaneous gastrostomy access, retrograde endoscopy and virtual gastroscopy using CT scan. We present a case of peptic ulcer bleeding diagnosed with the help of conventional CT scan. To the best of our knowledge, this is the second such case reported in the literature and the first in the bariatric population.  相似文献   
43.
OBJECTIVE: Distal embolization of plaque or thrombus may cause organ ischemia following percutaneous peripheral interventions. The purpose of this study was to evaluate the incidence and clinical significance of particulate embolization during percutaneous superficial femoral artery (SFA) intervention by monitoring with continuous Doppler ultrasound. The rate and timing of embolization at various phases of intervention such as guidewire crossing, balloon angioplasty, stent deployment, and directional atherectomy were analyzed and compared. METHODS: Sixty patients underwent SFA intervention. Of these 60 patients, 10 patients underwent percutaneous transluminal angioplasty (PTA) alone, 40 patients underwent PTA with stenting, and 10 patients underwent plaque excision with the SilverHawk atherectomy device (8) or Spectranetics excimer laser (2) with or without additional PTA or stent placement. A 4-MHz Doppler probe was used for continuous monitoring in the ipsilateral popliteal artery. Distal embolization was registered as embolic signals (ES). ES were quantitatively assessed during critical portions of the procedure including guidewire crossing, balloon angioplasty, stent deployment and/or atherectomy. ES during different phases of intervention were compared using analysis of variance (ANOVA). RESULTS: ES was noted in every patient during wire crossing, angioplasty, stent deployment and atherectomy. The average number of ES noted during guidewire crossing was 8, PTA was 12, stent deployment was 28, SiverHawk atherectomy was 49, and Spectranetics excimer laser was 51. The frequency of ES was statistically higher during stent deployment vs wire crossing or balloon angioplasty but equivalent to that generated by plaque excision. ES was observed more frequent during balloon angioplasty than during wire crossing. In one patient who was treated with the excimer laser, a single runoff vessel was occluded with embolic debris but patency was restored angiographically after thrombolysis. The patient went on to require below knee amputation. During follow-up, all patients with claudication reported improved symptoms and those with ulcers or gangrene demonstrated healing. The average increase in ankle-brachial index following intervention was 0.31. CONCLUSION: While ES were recorded at each step of SFA intervention, the frequency was greatest during stent deployment. Despite the frequency of these events, only one patient developed angiographically and clinically significant embolization. Thus, our findings do not support the routine use of protection devices during percutaneous SFA intervention.  相似文献   
44.
OBJECTIVE: The aim of this study was to examine the effects of small changes in PaCO(2) on hemodynamic parameters after uncomplicated heart surgery with cardiopulmonary bypass. DESIGN: This was a prospective, randomized crossover study. SETTING: A large academic medical center. PARTICIPANTS: Twenty-four subjects who were scheduled for elective cardiac surgery were enrolled in this study. INTERVENTIONS: Each subject underwent the normal procedures that are associated with cardiac surgery. General anesthesia, including muscle relaxation, were continued in the immediate postoperative period. Measured tidal volumes and minute ventilation were kept constant for the duration of the study. Target PaCO(2) concentrations of 30, 40, and 50 mmHg were achieved by adding varying amounts of exogenous CO(2) gas to the inhaled oxygen. Various measurements were made at each target PaCO(2), including cardiac index, mixed venous oxygen saturation, blood pressure, heart rate, and pulmonary artery pressure. MEASUREMENTS AND MAIN RESULTS: Twenty-four patients were enrolled. Seven were withdrawn before commencement of the study. The cardiac index increased when the PaCO(2) was increased from 30 to 40 mmHg (p < 0.001) and remained unchanged between 40 and 50 mmHg. Mixed venous oxygen saturation increased (p < 0.001) with elevations in PaCO(2) up to 50 mmHg and decreased again when the PaCO(2) was returned to 30 mmHg. The blood pressure decreased (p < 0.001) with increasing PaCO(2). The pulmonary pressure increased (p < 0.001) with elevations in PaCO(2). No patient became hemodynamically unstable or had any arrhythmias. CONCLUSION: The findings of this study suggest that unless there is a specific contraindication to mild hypercapnia, such as pulmonary hypertension or hemodynamic instability, concerns about mild respiratory acidosis should not prevent weaning of sedation and mechanical ventilation after uncomplicated heart surgery.  相似文献   
45.

Background  

Increasingly, laparoscopic biliary surgeons are undertaking laparoscopic cholecystectomy and laparoscopic common bile duct exploration for patients with cholelithiasis and choledocholithiasis. In laparoscopic common bile duct exploration a flexible choledochoscope is ordinarily used, and with this instrument the surgeon usually fails to remove large impacted stones. In contrast with use of a rigid nephroscope it is possible to remove all common bile duct stones irrespective of size and degree of impaction. The present study evaluates the efficiency of rigid nephroscope for managing common bile duct stones laparoscopically.  相似文献   
46.
47.
Thirty-eight patients with mammary gland tuberculosis were evaluated over a 5-year period presenting to the surgical unit of our institution. Unilateral involvement of the breast in a woman presenting at an average age of 29 years was the commonest observation. A lump in the breast with or without discharging sinuses was the most common clinical presentation. Ten (26%) of these patients had breast pain with or without increased breast nodularity. Axillary lymph nodal involvement was evident in 14 (36%) of our patients. Only five patients had associated pulmonary tuberculosis, the rest having an isolated involvement of the breast. Fine-needle aspiration cytology was the most reliable diagnostic modality. Medical therapy with antitubercular drugs ranging from 6 to 9 months was the mainstay of treatment. Surgical intervention was reserved for selected refractory cases.  相似文献   
48.
We present the case of a 52-year-old man, with a history of malignant melanoma, who presented with a testicular lump. Radical orchidectomy confirmed a metastatic malignant melanoma. We discuss salient features of this disease in the light of the published literature.  相似文献   
49.
Synovial fluid (SF) leptin has been shown to have an association with cartilage degeneration. Our objective was to examine the relationship between different measures of body habitus and SF leptin levels in an end‐stage knee osteoarthritis (OA) population. Sixty consecutive patients with knee OA were surveyed prior to surgery for demographic data. Body habitus was assessed with the body mass index (BMI), waist circumference (WC), and waist–hip ratio (WHR). SF and serum samples were analyzed for leptin and adiponectin using specific ELISA. Nonparametric correlations and linear regression modeling was used to identify the relationship between the measures of body habitus and SF leptin levels. Females had greater levels of leptin than males in both the serum and SF. Significant correlations were found between SF leptin levels and BMI and WC (R2 0.44 and 0.38, respectively; p < 0.05). Regression modeling showed that female gender and WC were independent predictors of a greater SF leptin level independent of age, BMI, and presence of diabetes (p < 0.05). WC may be a more accurate measure of body habitus than BMI in the relationship between the metabolic effects of adipose tissue and OA. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:329–333, 2010  相似文献   
50.
While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age‐related bone loss, we sham‐operated, ovariectomized, or ovariectomized and estrogen‐replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six‐month‐old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham‐operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen‐treated mice did not prevent age‐related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age‐related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham‐operated mice. As compared with cells from young mice, lin– cells from aged/sham‐operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age‐related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.  相似文献   
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