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Background Natural-orifice translumenal endoscopic surgery (NOTES) is a possible advancement for surgical interventions. We initiated a pilot study in humans to investigate feasibility and develop the techniques and technology necessary for NOTES. Reported herein is the first human clinical trial of NOTES, performing transoral transgastric diagnostic peritoneoscopy. Methods Patients were scheduled to undergo diagnostic laparoscopic evaluation of a pancreatic mass. The findings of traditional laparoscopy were recorded by anatomical abdominal quadrant. A second surgeon, blinded to the laparoscopic findings, performed transgastric peritoneoscopy. Diagnostic findings between the two methods were compared and operative times and clinical course were recorded. Definitive care was based on findings at diagnostic laparoscopy. Results Ten patients completed the protocol with an average age of 67.6 years. All patients underwent diagnostic laparoscopy followed by successful transgastric access and diagnostic endoscopic peritoneoscopy. The average time of diagnostic laparoscopy was 12.3 minutes compared to 24.8 minutes for the transgastric route. Transgastric abdominal exploration corroborated the decision to proceed to open exploration made during traditional laparoscopic exploration in 9 of 10 patients. Peritoneal or liver biopsies were obtained in four patients by traditional laparoscopy and in one patient by the transgastric access route. Findings were confirmed by laparotomy in nine patients. Eight patients underwent pancreaticoduodenectomy and two underwent palliative gastrojejunostomy and/or hepaticojejunostomy. Conclusions Transgastric diagnostic peritoneoscopy is safe and feasible. This study demonstrates the initial steps of NOTES in humans, providing a potential platform for incisionless surgery. Technical issues, including instrumentation, visualization, intra-abdominal manipulation, and gastric closure need further development.  相似文献
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Ergonomic problems associated with laparoscopic surgery   总被引:16,自引:16,他引:6  
Background: The Society of American Gastrointestinal Endoscopic Surgeons (SAGES) Task Force on Ergonomics conducted a subjective and objective assessment of ergonomic problems associated with laparoscopic instrument use. The goal was to assess the prevalence, causes, and consequences of operational difficulties associated with the use of laparoscopic instruments. Methods: A questionnaire was distributed asking respondents to rate the frequency with which they experienced pain, stiffness, or numbness in several body areas after laparoscopic operations. An ergonomics station was assembled to quantify forearm and thumb muscle workload. Processed electromyogram (EMG) signals were acquired from 27 volunteer surgeon subjects while they completed simulated surgical tasks using a hemostat and an Ethicon® laparoscopic grasper, with the aid of an endoscopic trainer and video monitoring system. Results: Of 149 surgeons responding to the questionnaire, 8% to 12% reported frequent pain in the neck and upper extremities associated with laparoscopic surgery. The ergonomics station demonstrated that the peak and total muscle effort of forearm and thumb muscles were significantly greater (p < 0.01) when the grasping task was performed using the laparoscopic instrument rather than the hemostat. Conclusion: These findings indicate that laparoscopic surgical technique is more taxing on the surgeon.  相似文献
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Background: Surgical management of the supersuper obese patient (BMI >60 kg/m2) has been a challenging problem associated with higher morbidity, mortality, and long-term weight loss failure. Current limited experience exists with a two-stage biliopancreatic diversion and duodenal switch in the supersuper obese patient, and we now present our early experience with a two-stage gastric bypass for these patients. Methods: We completed a retrospective bariatric database and chart review of super-super obese patients who underwent laparoscopic sleeve gastrectomy as a first-stage procedure followed by laparoscopic Roux-en-Y gastric bypass as a second-stage for more definitive treatment of obesity. Results: During a two-year period, 7 patients with BMI 58-71 kg/m2 underwent a two-stage laparoscopic Roux-en-Y gastric bypass by two surgeons at the Mount Sinai Medical Center. 3 patients were female, 4 patients were male, and the average age was 43. Prior to the sleeve gastrectomy, the mean weight was 181 kg with a BMI of 63. Average time between procedures was 11 months. Prior to the second-stage procedure, the mean weight was 145 kg with a BMI of 50 and average excess weight loss of 37 kg (33% EWL). Six patients have had follow-up after the second-stage procedure with an average of 2.5 months. At follow-up the mean weight was 126 kg with a BMI of 44 and average excess weight loss of 51 kg (46% EWL). The mean operative times for the two procedures were 124 and 158 minutes respectively. The average length of stay for all procedures was 2.7 days. 4 patients had 5 complications, which included splenic injury, proximal anastomotic stricture, left arm nerve praxia, trocar site hernia, and urinary tract infection.There were no mortalities in the series. Conclusions: Laparoscopic sleeve gastrectomy with second-stage Roux-en-Y gastric bypass are feasible and effective procedures based on short-term results. This two-stage approach is a reasonable alternative for surgical treatment of the high-risk supersuper obese patient.  相似文献
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Body mass index as a predictor of fracture risk: A meta-analysis   总被引:15,自引:15,他引:11  
Low body mass index (BMI) is a well-documented risk factor for future fracture. The aim of this study was to quantify this effect and to explore the association of BMI with fracture risk in relation to age, gender and bone mineral density (BMD) from an international perspective using worldwide data. We studied individual participant data from almost 60,000 men and women from 12 prospective population-based cohorts comprising Rotterdam, EVOS/EPOS, CaMos, Rochester, Sheffield, Dubbo, EPIDOS, OFELY, Kuopio, Hiroshima, and two cohorts from Gothenburg, with a total follow-up of over 250,000 person years. The effects of BMI, BMD, age and gender on the risk of any fracture, any osteoporotic fracture, and hip fracture alone was examined using a Poisson regression model in each cohort separately. The results of the different studies were then merged. Without information on BMD, the age-adjusted risk for any type of fracture increased significantly with lower BMI. Overall, the risk ratio (RR) per unit higher BMI was 0.98 (95% confidence interval [CI], 0.97–0.99) for any fracture, 0.97 (95% CI, 0.96–0.98) for osteoporotic fracture and 0.93 (95% CI, 0.91–0.94) for hip fracture (all p <0.001). The RR per unit change in BMI was very similar in men and women ( p >0.30). After adjusting for BMD, these RR became 1 for any fracture or osteoporotic fracture and 0.98 for hip fracture (significant in women). The gradient of fracture risk without adjustment for BMD was not linearly distributed across values for BMI. Instead, the contribution to fracture risk was much more marked at low values of BMI than at values above the median. This nonlinear relation of risk with BMI was most evident for hip fracture risk. When compared with a BMI of 25 kg/m2, a BMI of 20 kg/m2 was associated with a nearly twofold increase in risk ratio (RR=1.95; 95% CI, 1.71–2.22) for hip fracture. In contrast, a BMI of 30 kg/m2, when compared with a BMI of 25 kg/m2, was associated with only a 17% reduction in hip fracture risk (RR=0.83; 95% CI, 0.69–0.99). We conclude that low BMI confers a risk of substantial importance for all fractures that is largely independent of age and sex, but dependent on BMD. The significance of BMI as a risk factor varies according to the level of BMI. Its validation on an international basis permits the use of this risk factor in case-finding strategies.  相似文献
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An Assessment Tool for Predicting Fracture Risk in Postmenopausal Women   总被引:14,自引:14,他引:7  
Due to the magnitude of the morbidity and mortality associated with untreated osteoporosis, it is essential that high-risk individuals be identified so that they can receive appropriate evaluation and treatment. The objective of this investigation was to develop a simple clinical assessment tool based on a small number of risk factors that could be used by women or their clinicians to assess their risk of fractures. Using data from the Study of Osteoporotic Fractures (SOF), a total of 7782 women age 65 years and older with bone mineral density (BMD) measurements and baseline risk factors were included in the analysis. A model with and without BMD T-scores was developed by identifying variables that could be easily assessed in either clinical practice or by self-administration. The assessment tool, called the FRACTURE Index, is comprised of a set of seven variables that include age, BMD T-score, fracture after age 50 years, maternal hip fracture after age 50, weight less than or equal to 125 pounds (57 kg), smoking status, and use of arms to stand up from a chair. The FRACTURE Index was shown to be predictive of hip fracture, as well as vertebral and nonvertebral fractures. In addition, this index was validated using the EPIDOS fracture study. The FRACTURE Index can be used either with or without BMD testing by older postmenopausal women or their clinicians to assess the 5-year risk of hip and other osteoporotic fractures, and could be useful in helping to determine the need for further evaluation and treatment of these women. Received: 7 November 2000 / Accepted: 23 May 2001  相似文献
7.
Rib Fracture Repair: Indications,Technical Issues,and Future Directions   总被引:14,自引:0,他引:14  
Rib fracture repair has been performed at selected centers around the world for more than 50 years; however, the operative indications have not been established and are considered controversial. The outcome of a strictly nonoperative approach may not be optimal. Potential indications for rib fracture repair include flail chest, painful, movable rib fractures refractory to conventional pain management, chest wall deformity/defect, rib fracture nonunion, and during thoracotomy for other traumatic indication. Rib fracture repair is technically challenging secondary to the human rib’s relatively thin cortex and its tendency to fracture obliquely. Nonetheless, several effective repair systems have been developed. Future directions for progress on this important surgical problem include the development of minimally invasive techniques and the conduct of multicenter, randomized trials.  相似文献
8.
Estimates of optimal vitamin D status   总被引:13,自引:13,他引:9  
Vitamin D has captured attention as an important determinant of bone health, but there is no common definition of optimal vitamin D status. Herein, we address the question: What is the optimal circulating level of 25-hydroxyvitamin D [25(OH)D] for the skeleton? The opinions of the authors on the minimum level of serum 25(OH)D that is optimal for fracture prevention varied between 50 and 80 nmol/l. However, for five of the six authors, the minimum desirable 25(OH)D concentration clusters between 70 and 80 nmol/l. The authors recognize that the average older man and woman will need intakes of at least 20 to 25 mcg (800 to 1,000 IU) per day of vitamin D3 to reach a serum 25(OH)D level of 75 nmol/l. Based on the available evidence, we believe that if older men and women maintain serum levels of 25(OH)D that are higher than the consensus median threshold of 75 nmol/l, they will be at lower risk of fracture.  相似文献
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10.
Background: The objective assessment of the psychomotor skills of surgeons is now a priority; however, this is a difficult task because of measurement difficulties associated with the assessment of surgery in vivo. In this study, virtual reality (VR) was used to overcome these problems. Methods: Twelve experienced (>50 minimal-access procedures), 12 inexperienced laparoscopic surgeons (<10 minimal-access procedures), and 12 laparoscopic novices participated in the study. Each subject completed 10 trials on the Minimally Invasive Surgical Trainer; Virtual Reality (MIST VR). Results: Experienced laparoscopic surgeons performed the tasks significantly (p < 0.01) faster, with less error, more economy in the movement of instruments and the use of diathermy, and with greater consistency in performance. The standardized coefficient alpha for performance measures ranged from a = 0.89 to 0.98, showing high internal measurement consistency. Test–retest reliability ranged from r = 0.96 to r = 0.5. Conclusion: VR is a useful tool for evaluating the psychomotor skills needed to perform laparoscopic surgery.  相似文献
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