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31.
PURPOSE: The aim of this report was to compare polyester vs. bovine pericardial patching during CEA with regards to the incidence of early neurologic events and recurrent stenosis. PATIENTS AND METHODS: One hundred and twenty-five consecutive patients with high grade symptomatic (14%) or asymptomatic (86%) carotid artery stenosis (>70%) who underwent 139 CEAs by a single surgeon between January 1997 and April 2001 were retrospectively reviewed. Patients were assessed postoperatively clinically and with routine follow-up duplex scanning. Recurrent stenosis was defined as a narrowing in the common or internal carotid artery of more than 50% by duplex ultrasound examination. RESULTS: From January 1997 to May 1999, a polyester patch was routinely used in 81 (58%) patients, while between June 1999 and April 2001, a bovine pericardium patch was exclusively used in 59 (42%) patients. There were no ipsilateral postoperative TIAs or strokes in either group. The combined 30-day mortality rate for both groups was 0.8%. One patient in the polyester patch group died from cardiopulmonary complications 10 days after discharge. The length of follow-up in the bovine pericardial patch group was 3-28 months (mean 12 months), while in the polyester patch group was 1-50 months (mean 24.5 month). One patient developed a carotid pseudoaneurysm of the suture line in the bovine pericardium patch group caused by a local infection after previous neck dissection and radiation. The incidence of recurrent stenosis was two patients (4%) in the bovine pericardium group as opposed to six patients (7.6%) in the polyester patch group. CONCLUSION: Although this is a preliminary report, it is concluded that bovine pericardium provides excellent perioperative results and is at least comparable to polyester patching in terms of safety. Our study with short term follow up suggests that bovine pericardium patching during carotid endarterectomy may have a lower restenosis rate compared to knitted polyester patching. Clear superiority of bovine pericardium as a patch material awaits a prospective randomised study with long-term follow-up.  相似文献   
32.

Purpose

We compared renal function outcomes among patients in the surveillance and intervention arms of the DISSRM registry.

Materials and methods

Patients were grouped into chronic kidney disease stages by estimated glomerular filtration rate range. Cases were considered up staged if a more advanced chronic kidney disease stage was entered during followup. Chronic kidney disease up staging-free survival was compared among groups using Kaplan-Meier analysis and paired comparisons log rank tests. Multivariate Cox regression identified independent predictors of chronic kidney disease up staging-free survival.

Results

A total of 162 patients met the study inclusion criteria, with 68 in the surveillance arm, 65 undergoing partial nephrectomy, 15 undergoing radical nephrectomy, and 14 undergoing cryoablation. Median tumor size was 2.2 cm. Mean estimated glomerular filtration rate change was significantly larger for radical nephrectomy vs. surveillance (?9.2 vs. ?0.5 ml/min/1.73 m2) and for radical vs. partial nephrectomy (?9.2 vs. ?1.9 ml/min/1.73 m2) (P = 0.001). No other groups differed significantly. On Kaplan-Meier analysis, patients undergoing radical nephrectomy had significantly worse chronic kidney disease up staging-free survival vs. those treated with partial nephrectomy (P = 0.029), surveillance (P = 0.007), and cryoablation (P = 0.019). No other groups differed significantly. On multivariate analysis, radical nephrectomy independently predicted poor chronic kidney disease up staging-free survival (odds ratio vs. surveillance 30.6, P = 0.001). Neither partial nephrectomy (P = 0.985) nor cryoablation (P = 0.976) predicted poor chronic kidney disease up staging-free survival relative to surveillance.

Conclusions

Patients in the surveillance arm had superior estimated glomerular filtration rate preservation compared to those in the radical nephrectomy but not the partial nephrectomy arm. In certain patients with small renal masses, surveillance and partial nephrectomy may offer comparable renal functional outcomes. This could be partly attributable to a modest estimated glomerular filtration rate decrease associated with surveillance itself. A thorough understanding of the renal functional impacts of treatment modalities is critical in the management of small renal masses.  相似文献   
33.
The purpose of this paper is to describe the intraoperative management of a type IIIb endoleak after deployment of a bifurcated endograft in a patient with narrow iliac access vessels. A 62-year-old man underwent elective endovascular repair (EVAR) of a 53 mm abdominal aortic aneurysm. After device deployment, a large IIIb endoleak, arising from the main body of the device, was visualized. Narrow iliac vessels precluded deployment of a second bifurcated graft, and the endoleak was successfully excluded with an aortomonoiliac device, followed by contralateral iliac occlusion and subsequent creation of a femorofemoral bypass. At 1-year follow-up, the aneurysm remains excluded and is decreasing in size. Type III endoleaks are a known complication of EVAR, requiring immediate treatment through their association with aneurysm enlargement and rupture. If an additional bifurcated graft cannot be used, aortomonoiliac conversion represents a feasible endovascular alternative treatment for type III endoleaks, other than conversion to open surgical repair. Therefore, aortomonoiliac converters with appropriate occluder devices should be readily available during deployment of bifurcated devices.  相似文献   
34.
Objective  To assess the main characteristics of late relapsing malignant germ cell tumors (MGCTs). These tumors are rare and occur by definition 2 years or later after successful treatment. Methods  We present relevant literature on relapsing MGCT in order to highlight the following issues: incidence, impact of initial treatment on the subsequent risk of late relapse, treatment, and survival. Results  A pooled analysis of 5,880 patients with MGCT revealed late relapses in 119 of 3,704 (3.2%) and in 31 of 2,176 (1.4%) patients with non-seminoma and seminoma, respectively. The retroperitoneal space is the predominant site of relapse in both histological types. The initial treatment is important for the risk and localization of late relapses. Patients with single site teratoma are usually cured by surgery alone, whereas viable MGCT or teratoma with malignant transformation may require multimodal treatment with chemo- and/or radiotherapy as well as surgery. Surgery is the most important part in the treatment of late relapses. Salvage chemotherapy should, if feasible, be based on a representative biopsy. Five-year cancer-specific survival is above 50% in the recent large series and reaches 100% in case of single site teratoma. Conclusions  Treatment of late relapsing MGCT patients is challenging and should be performed in experienced centers only. Referral of late relapsing patients to high-volume institutions ensures the best chances of cure and enables multimodal treatment, and contributes to increased knowledge of tumor biology as well experience with the clinical course of these patients.  相似文献   
35.
目的:高血压常伴有纤溶功能的异常,但其机制尚不清楚。本研究拟观察高静水压培养对人脐静脉内皮细胞(HUVECs)t-PA和PAI-1的影响以及卡托普利的干预效果,并探讨其可能的作用机制。方法:选用第4~6代HU-VECs,接种于24孔培养板中。依培养压力分为3组:大气压组(0mmHg),中压组(90mmHg),高压组(180mmHg)。在同一压力组,根据不同药物干预又分为两个亚组。即对照组(Ctrl)和卡托普利组(Cap,10^-5mol/L)。每组6份标本。采用ELISA法测定上清液t-PA和PAI-1的抗原浓度,并用细胞内总蛋白进行标化(单位:ng/μg proteins)。同时测定细胞内Ca^2+浓度(nmol/L)。结果:与大气压组相比,中压和高压组t-PA浓度均显著降低,PAI-1浓度显著增高,t-PA/PAI-1比值显著降低,[Ca^2+]i也显著增高。卡托普利对大气压组的t-PA、PAI-1和[Ca^2+]i无显著影响,但在两个高压组,卡托普利显著升高t-PA浓度,显著降低PAI-1浓度,t-PA/PAI-1比值显著升高,[Ca^2+]i显著地降低。结论:高静水压可损害内皮细胞的纤溶功能,而卡托普利的干预可降低高压所升高的[Ca^2+]i,并改善高静水压对内皮细胞纤溶功能的影响。  相似文献   
36.
Wood  GS; Garcia  CF; Dorfman  RF; Warnke  RA 《Blood》1985,66(5):1092-1097
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.  相似文献   
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Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
40.
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