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41.
Background The value of re-exploration for pancreatic ductal adenocarcinoma after the initial diagnosis of unresectability is unclear. Methods In this study, we analyzed 33 patients who were re-explored after an initial diagnosis of unresectability. Results At the time of reoperation, a resectable tumor was found in 18 patients: therefore, 15 pancreaticoduodenectomies, two total pancreatectomies and one left resection were performed with three vascular resections. Morbidity and mortality rates for the cohort were 6/33 and 1/33, without significant differences between resectable and nonresectable patients. Length of stay, duration of operation, and blood loss were significantly increased in the resection group. Kaplan–Meier survival analysis demonstrated increased median survival for resected patients (1078 days after the initial operation versus 547 days in the group of unresectable patients; p = 0.018). Analysis of the reasons against initial resection showed that, if the patients had been sent to a tertiary referral center for pancreatic surgery, a different decision in favor of resection would probably have been made in 14 out of 33 patients. A review of 10 published reports on reoperation for pancreatic cancer revealed results comparable to our study in terms of low morbidity and mortality as well as a survival benefit. Conclusions Reoperation for pancreatic ductal adenocarcinoma that is initially deemed unresectable can be safely performed in a selected group of patients by experienced surgeons, supporting the concept of patient centralization in pancreatic surgery. Resection at the second operation may confer a survival benefit even when the initial findings preclude a potentially curative approach.  相似文献   
42.
Introduction/BackgroundEffective cancer biomarkers for early detection, prognosis, or therapy response prediction are urgently need in metastatic RCC. M30 and M65 are released during apoptotic cell death and precisely reflect epithelial tumor cell death. The aim of this study was to determine the prognostic value of plasma M30 and M65 levels in predicting survival rates for patients with metastatic RCC.Patients and MethodsThirty-nine patients with metastatic RCC and 39 healthy control subjects were included in this study. Serum M30 and M65 levels were measured by ELISA.ResultsThe median ages of the patients and control subjects were 60 and 58 years, respectively. No difference was detected in the median serum M30 level between the patients and control subjects (53.7 vs. 49.1 U/L; P = .31). The median serum M65 level was significantly higher in patients than in control subjects (334.0 vs. 179.1 U/L; P < .001). Receiver operating characteristic analysis revealed that the best cutoff value for serum M65 level for predicting progression-free survival (PFS) was 313.6 U/L. The median PFS of patients whose M65 levels were ≤ 313.6 U/L was better than that of patients whose M65 levels were > 313.6 U/L (P = .03).ConclusionTo the best of our knowledge, this is the first study to evaluate serum M30 and M65 levels in patients with RCC. Serum M65 levels were significantly elevated in patients with metastatic RCC compared with healthy individuals. In addition, the serum M65 level could be predictive of PFS in patients with RCC.  相似文献   
43.
We used an unconventional endovascular approach for the treatment of traumatic carotid cavernous fistula. A patient with a large high-flow shunt was successfully treated by trapping the fistula using a combination of proximal balloon occlusion and distal coil embolization. The latter was achieved following retrograde catheterization of the distal parent vessel via the ipsilateral vertebral artery.  相似文献   
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Mert Erkan 《Pancreatology》2013,13(2):106-109
Since conventional and targeted therapies aiming at cancer cells have largely failed to prolong survival in pancreatic cancer, targeting the infrastructure of the tumor, hence its stroma is a novel strategy. It is believed that fibrotic and hypovascular stroma forms a barrier around cancer cells, hindering effective delivery of chemotherapy. Theoretically, antifibrotic therapy should reduce the compactness of the stroma and reduce the interstitial pressure, allowing better delivery of chemotherapy. This approach has worked successfully in a genetically engineered mouse model but failed in humans, paradoxically increasing mortality in the treatment arm. Normally, stromal cells deposit extracellular matrix as an innate defensive reaction to form a barrier between what is harmful and the rest of the body. Despite the significant amount of in vitro data suggesting the pro-tumorigenic roles of activated stellate cells, there is no reason to believe that stellate cells around genetically mutated cells are from the beginning there to support carcinogenesis. Such a stromal activation is also observed around PanIN lesions (which harbor genetically mutated cells) in chronic pancreatitis, where no cancer develops. In pancreatic cancer, the selection pressure created by the fibrotic and hypoxic stroma eventually leads to the evolution of more aggressive clones, indirectly contributing to the aggressiveness of the tumor. Here, the main problem is the late diagnosis of pancreatic cancer, which gives cancer cells enough time for malignant evolution. Therefore, applying antifibrotic therapy at a late stage can be counterproductive. It may increase delivery of chemotherapy, but also lead to the escape of cancer cells.  相似文献   
46.

Purpose  

This study aimed to investigate the extent of knowledge and use of emergency contraception among women of reproductive age and to identify barriers existing in Turkey in this context. There is limited research regarding the knowledge and use and barriers to emergency contraception use, since the prepackaged form of hormonal emergency contraception has been available over the counter in Turkey.  相似文献   
47.
Study ObjectiveTo quantify and compare the effects of conventional volume-controlled ventilation (VCV) with the alternative mode, pressure-controlled ventilation (PCV), on respiratory mechanics and noninvasive hemodynamic parameters in patients undergoing laparoscopic gynecologic surgery.DesignRandomized controlled trial (Canadian Task Force classification I).SettingRespiratory mechanics and hemodynamic parameters were recorded for each patient at time T1, 10 minutes after induction, in the supine position; T2, 15 minutes after pneumoperitoneum, in the Trendelenburg position; and T3, 10 minutes after pneumoperitoneum withdrawal, in the supine position.PatientsSixty women, aged 20 to 50 years, undergoing laparoscopic gynecologic surgery, with American Society of Anesthesiologists classes I and II disease.InterventionsPatients were randomly allocated to 1 of 2 groups. In the VCV group (n = 30), ventilation mode was maintained, whereas in the PCV group (n = 30), ventilation mode was changed to PVC.Measurements and Main ResultsBoth groups were comparable insofar as patient characteristics, operating time, pneumoperitoneum time, anesthesia time, and mean operative time. VCV was associated with a significant increase in peak airway pressure, plateau pressure, and airway resistance at T2 (p < .05). Compliance was significantly higher in the PCV group at T2 (p < .05). No other statistically significant differences were found between the groups.ConclusionsBoth VCV and PCV seem to be equally suited for use in patients undergoing laparoscopic gynecologic surgery. However, lower peak airway pressure, plateau pressure, and airway resistance, and higher compliance are observed with PCV in laparoscopic gynecologic surgery.  相似文献   
48.
One of the key factors that correlates with poor survival of patients with pancreatic cancer is the extent of hypoxic areas within the tumor tissue. The adaptation of pancreatic cancer cells to limited oxygen delivery promotes the induction of an invasive and treatment-resistant phenotype, triggering metastases at an early stage of tumor development, which resist in most cases adjuvant therapies following tumor resection. In this article, the authors summarize the evidence demonstrating the significance of hypoxia in pancreatic cancer pathogenesis and discuss the possible hypoxia-induced mechanisms underlying its aggressive nature. We then conclude with promising strategies that target hypoxia-adapted pancreatic cancer cells.  相似文献   
49.
Vascular reconstruction in Buerger's disease: is it feasible?   总被引:1,自引:0,他引:1  
Purpose: Thromboangiitis obliterans (Buerger's disease) is a clinical syndrome characterized by segmental occlusions of the distal vessels. Although a cessation of using nicotine products usually helps, nevertheless a surgical revascularization may be needed in cases of stage III and IV limbs. Because of the distal and segmental nature of the disease, these procedures are rarely feasible. This article focuses on the feasibility of performing a vascular reconstruction in thromboangiitis obliterans. Methods: Thirty-six of 94 patients (38.3%) who were followed by the Peripheral Vascular Unit of Istanbul Medical Faculty were selected for revascularization and 27 of 36 (81%) patients underwent revascularization procedures. Results: During a 36-month follow-up, the patency rates at the 12th, 24th, and 36th months were 59.2%, 48%, and 33.3%, respectively. The limb salvage rate was 92.5%. Conclusions: Since patients affected by Buerger's disease consist a group of young population who are still in their productive stages, every effort should be taken to obtain a limb salvage in the ischemic period. Although the patency rates do not seem promising, the limb salvation rate was quite satisfactory. Received: October 29, 2001 / Accepted: July 2, 2002 Reprint requests to: Ş. Dilege  相似文献   
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