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31.
Intraoperative radiation therapy for breast cancer: technical notes   总被引:3,自引:0,他引:3  
Interest in intraoperative radiation therapy (IORT) for breast cancer is increasing as the possible benefits of this technique for the patient become apparent. The rationale for the use of this segmental radiation therapy in place of whole-breast irradiation is based on the finding that approximately 85% of breast relapses are confined to the same quadrant of the breast as the primary tumor. Phase I and II trials have demonstrated no increase in postsurgical complication rates following the use of single-dose IORT in localized breast cancers. Longer follow-up is needed to assess the cosmetic outcome. Clinical trials to evaluate the effectiveness of IORT in the treatment of breast cancer are currently under way at the European Institute of Oncology (EIO) at the University of Milan, Italy, and at Memorial Sloan-Kettering Cancer Center (MSKCC) in New York. Here we report the two different techniques in use in these trials.  相似文献   
32.
1病例简介:我从未觉得我的生活是如此的糟糕Jessica,30岁,妊娠前一直从事专业技术工作,有1个6个月大的孩子。她说,在生完孩子后的最初3个月内,她有持续性的腹痛。几个月前,距离她重返工作岗位大约一半时间的时候,她感觉身体不适,并且在过去1个月里越来越严重。她所描述的早期症状是生理性的:恶心、头晕、极度嗜睡。她去看过几个医生,医生给她检测了血红蛋白水平,解释说这可能是哺乳和重返  相似文献   
33.
BACKGROUND AND OBJECTIVES: Clonidine is added to intrathecal local anesthetics to improve intraoperative analgesia and to increase the duration of sensory and motor block. The aim of this systematic review is to quantify beneficial and harmful effects of clonidine when used as an adjuvant to intrathecal local anesthetics for surgery. METHODS: We included data from 22 randomized trials (1,445 patients) testing a large variety of doses of clonidine, added to intrathecal bupivacaine, mepivacaine, prilocaine, or tetracaine. RESULTS: Clonidine 15 to 150 microg prolonged in a linear, dose-dependent manner, the time to 2 segment regression (range of means, 14 to 75 minutes) and the time to regression to L2 (range of means, 11 to 128 minutes). The time to first analgesic request (median 101 minutes, range 35 to 310) and of motor block (median 47 minutes, range 6 to 131) was prolonged without evidence of dose-responsiveness. Time to achieve complete sensory or motor block, and extent of cephalic spread remained unchanged. There were fewer episodes of intraoperative pain with clonidine (relative risk, 0.24; 95% confidence interval [CI], 0.09-0.64; number needed to treat, 13) but more episodes of arterial hypotension (relative risk, 1.81; 95% CI 1.44-2.28; number needed to harm, 8) without evidence of dose-responsiveness. The risk of bradycardia was unchanged. CONCLUSIONS: This study may serve as a rational basis to help clinicians decide whether or not to combine clonidine with an intrathecal local anesthetic for surgery. The optimal dose of clonidine, however, remains unknown.  相似文献   
34.
In patients with colorectal cancers synchronous neoplastic lesions are an increasingly frequent finding at preoperative staging; 3% of the cases are other cancers while 33-35% of the synchronous lesions are villous adenomas. The treatment of most colorectal adenomas can be performed by endoscopic poplypectomy. In 5% of cases there are synchronous colorectal lesions also requiring surgical treatment. From January 1995 to June 2007 we treated 5 patients with rectal lesions by transanal endoscopic microsurgery (TEM) together with a laparoscopic colectomy for the presence of synchronous lesions at the "Clinica Chirurgica Generale e d'Urgenza" of the University of Perugia,. Surgical timing involved performing a sequential exeresis characterised by a cancer resection, followed by resection of the voluminous adenoma: TEM for rectal cancer followed by a laparoscopic right hemicolectomy with an extracorporeal anastomosis for a voluminous villous adenoma (1 patient) and laparoscopic right hemicolectomy with an extracorporeal anastomosis for cancer followed by TEM for a voluminous villous adenoma (2 patients). One patient with left colon cancer associated with a voluminous villous rectal adenoma first underwent TEM for the rectal adenoma and then a left laparoscopic hemicolectomy with an extracorporeal anastomosis in order to ease the transit of the circular mechanical stapler. Another patient with rectal and right colon adenomas first underwent TEM for a voluminous rectal sessile adenoma and later a right hemicolectomy. The use of this minimally invasive approach allowed rectum preservation and less invasive surgery.  相似文献   
35.
PURPOSE: To assess whether PSA density (PSAD) and PSA density of the transition zone (PSADTZ) are more accurate than PSA alone in predicting the pathological stage of prostate cancer. MATERIALS AND METHODS: One hundred and nine consecutive patients with clinically localized prostate cancer and preoperative PSA values over the whole range, treated with radical retropubic prostatectomy and limited pelvic lymph node dissection were included in this prospective study. Total prostate and transition zone volumes were measured by transrectal ultrasound using the prolate ellipsoid method. PSA, PSAD, and PSADTZ were compared to percentage of positive biopsy cores (% PC), biopsy and surgical Gleason score, and pathological stage, using univariate and multivariate analysis. RESULTS: Pathological stage was pT2a, pT2b, pT3a, and pT3b in 25.6%, 37.7%, 25.6%, and 11.1% of patients, respectively. Lymph node metastases were found in 4.6% of patients. PSA, PSAD, and PSADTZ were significantly related to % PC, biopsy, and surgical Gleason score and pathological stage (P < 0.001), and were equally able to predict higher pathological stage, i.e., seminal vesicle invasion and lymph node metastases. Only by adding % PC in multivariate analysis was it possible to discriminate intra- from extracapsular tumors. CONCLUSIONS: The results of the present study demonstrate that PSAD and PSADTZ failed to outperform PSA in preoperative stage prediction of prostate cancer, possibly because the formula used to calculate them does not eliminate the contribution to total PSA of the nonmalignant portion of the gland.  相似文献   
36.
In the early days of video-assisted laparoscopic cholecystectomy (VLC), obesity was considered a contraindication for the procedure. We reviewed charts from 304 patients undergoing VLC; 90 patients were obese, and among these, according to a classification currently used by medical nutritionists and based on BMI, 45 were overweight (BMI > or = 25 < or = 29.9), 27 were considered conventionally obese (BMI > or = 30 and < 40) and 18 morbidly obese (BMI > or = 40). In this study we considered only the morbidly obese patients (5 males and 13 females). The average age was 42.3 years (range: 21-65) and the average weight 275 Ib (range: 186-331 Ib). Six patients had previously undergone abdominal surgery. All patients were symptomatic for gallstones, and 5 of them were suffering from acute cholecystitis. Mean operative time was 20 minutes (range: 10-45 minutes) longer than that of non-obese patients. No open conversion was necessary. No major postoperative morbidity and no cases of mortality occurred. The mean hospital stay and resumption of normal diet were similar to those of non-obese patients. Regardless of the higher postoperative risks after open cholecystectomy in obese patients (pulmonary complications, thromboembolism, wound infections and cardiovascular complications), we suggest VLC as the procedure of choice for cholecystectomy in these patients.  相似文献   
37.

Background  

Liver transplantation in presence of diffuse portal vein thrombosis is possible by using caval blood as portal inflow, through cavo-portal transposition. However, clinical results are heterogeneous and experimental studies are needed, but similar hemodynamic conditions are difficult to obtain, especially in small animals. Herein we describe a new simple model of cavo-portal transposition in rat.  相似文献   
38.
At the European Institute of Oncology, Milan, Italy, we have focused our interest on the use of intraoperative radiation therapy (IORT) in limited-stage breast cancer that is conservatively treated. A new technique to perform IORT was applied in 185 patients from July 1, 1999, to October 31, 2001. As the surgeon plays a crucial role in this procedure in selecting the patients, performing the breast resection, preparing the gland as a target to receive IORT, delivering the radiation directly to the mammary gland via a dedicated applicator, and, finally, reconstructing the breast, each phase of the surgical technique has been completely standardized and is described herein. The use of IORT in the conservative treatment of breast cancer could allow the course of external fractionated-dose radiation therapy to be completely avoided; IORT dramatically reduces radiation exposure of the skin, lung, and subcutaneous tissues and avoids the irradiation of the contralateral breast, which contributes to a very low incidence of radiation-induced sequelae. In our experience, IORT for limited-stage breast carcinoma is easy to perform and only briefly prolongs the duration of the surgical procedure.  相似文献   
39.
BACKGROUND: Stentless bioprostheses and homografts show better hemodynamic profiles compared with conventional stented bioprostheses and mechanical valves. Few data are available on stentless aortic valve implantation for patients with severe left ventricular dysfunction. The aim of this retrospective study was to assess the potential benefits of stentless aortic valve implantation for patients undergoing isolated aortic valve replacement with left ventricular ejection fraction < or = 35%. METHODS: From November 1988 through March 2000, 53 patients (45 men and 8 women, aged 64.2 +/- 15.2 years) with a LVEF < or = 35% (mean EF, 28.7 +/- 5.4%) underwent isolated, primary aortic valve replacement for chronic aortic valve disease. Twenty patients received stentless aortic valves and 33 patients received conventional stented bioprostheses and mechanical valves. Predictive factors for LVEF recovery at echocardiographic follow-up (36.2 +/- 32.1 months) were analyzed by simple and multiple regression analysis. RESULTS: There were no significant differences between groups in early and late mortality. Stentless aortic valve implantation required a longer aortic cross-clamp time (p = 0.037). The stentless aortic valve group showed a better LVEF recovery (p = 0.016). Stentless aortic valves had a larger indexed effective orifice area compared with conventional stented bioprostheses and mechanical valves (p < 0.0001). A smaller indexed effective orifice area (p = 0.0008), chronic obstructive pulmonary disease (p = 0.015), and implantation of a conventional stented bioprosthesis or mechanical valve (p = 0.016) were related to reduced LVEF recovery by univariate analysis. A larger indexed effective orifice area (p = 0.024) was an independent predictive factor for a better LVEF recovery by multivariate analysis. CONCLUSIONS: Stentless aortic valve implantation for patients with severe left ventricular dysfunction, even if technically more demanding, is a safe procedure that warrants a larger indexed effective orifice area leading to an enhanced LVEF recovery.  相似文献   
40.
Objective: Severe atherosclerosis of the ascending aorta and arch frequently causes difficulties during heart operations, hindering surgical manoeuvres and potentially leading to systemic embolism. The aim of our study was to assess the safety and effectiveness of replacing the atherosclerotic ascending aorta in this setting. Methods: Aortic atherosclerosis was characterized by epiaortic ultrasonographic scanning in 90.1% of 1927 consecutive adult patients undergoing cardiac operations, and by computed tomographic chest scanning in selected cases. Thirty-six of the 152 patients requiring major derangements from our standard practice due to aortic atherosclerosis underwent replacement of the ascending aorta and constitute the study group. Replacement of the aorta was extended to the arch in 13 cases (36.1%). It was associated with single or multiple valve surgery in 34 patients (94.4%) and with coronary revascularization in 30 (83.3%). Two patients (5.6%) underwent coronary bypass grafting without valve surgery. A cryoablation procedure was associated in three patients with permanent atrial fibrillation. Deep hypothermic circulatory arrest was employed in 34 patients (94.4%), while proximal aortic disease allowed conventional distal crossclamping in 2 cases. The risk of operative mortality was estimated by the logistic EuroSCORE both with and withholding the variable ‘surgery of the thoracic aorta’. All survivors were followed-up for 1–41 months (16 ± 12). Results: Two patients died in the hospital (5.6%) and two during follow-up, for a cumulative survival of 91.3% and 85.6% at 1 and 3 years, respectively (hospital deaths included). The hospital death rate compared favourably with the expected estimates of 25.5% (p < 0.05) and 10.3% (p = 0.67) obtained by the EuroSCORE full model and without ‘aortic surgery’, respectively. In-hospital adverse neurologic events occurred in six patients (16.7%), including stroke in one patient (2.8%) and neurocognitive disturbances in five (13.9%), although they were all transient and cleared before discharge. Excess bleeding required re-exploration in four patients (11.1%), and one more patient underwent emergency grafting for acute postoperative coronary occlusion. Ten patients (38.5%) were intubated for longer than 24 h. Conclusion: Despite significant perioperative morbidity, replacement of the severely atherosclerotic aorta is worth consideration to avert expectedly higher death and stroke rates.  相似文献   
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