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91.
Thrombin activatable fibrinolysis inhibitor (TAFI), a recently described inhibitor of fibrinolysis, has been hypothesized as playing a role in atherothrombosis. However, the evidence from retrospective studies, which have evaluated the role of TAFI in vascular risk, is conflicting. In a prospective cohort (the PRIME Study) of nearly 10 000 apparently healthy men recruited in France (Lille, Strasbourg, Toulouse) and Northern Ireland (Belfast), we measured baseline plasma concentration of TAFI antigen among 143 participants (81 from France and 62 from Ireland) who subsequently developed angina pectoris and among 286 age-matched participants who remained free of disease during the 5 years of follow-up. Genotyping of the Ala147Thr polymorphism located in the TAFI gene was performed using an allele specific PCR. In France, mean levels of TAFI were significantly higher at baseline among men who subsequently developed angina pectoris compared with their control subjects (119 versus 107 %; p = 0.02). The risk of future angina pectoris increased with increasing tertiles of TAFI (p = 0.02), such that men in the highest tertile at study entry had a 5-fold higher relative risk than those in the lowest tertile (95% confidence interval, 1.38 to 18.58) after controlling for the conventional cardiovascular risk factors. No such difference was observed in Northern Ireland. In France, Thr/Thr carriers of the Ala147Thr polymorphism were significantly more frequent in cases than in controls (p = 0.01) leading to a relative risk of angina pectoris of 2.7 (95%CI 1.2-5.8). Increase in plasma TAFI antigen levels is a risk factor for angina pectoris in France. Genotyping for the Ala147Thr polymorphism seems to be a reliable tool to assess the risk mediated by TAFI.  相似文献   
92.
PURPOSE: During the last five years the use of unenhanced helical CT (HTC) has been proposed as a preliminary diagnostic approach in patients with typical renal colics or with nonspecific flank pain. The aim of this study was to describe our experience in this field. MATERIAL AND METHODS: 130 consecutive patients (82 men and 48 women, with an average age of 54 years) were studied; 94 of them presented typical renal colics, while 36 presented acute flank pain. The parameters used were: 5-mm-thick sections, a pitch of 1.6, a reconstruction interscan spacing at 3 mm, an examination area extending from the kidneys to the base of the bladder. Depending on the case, examinations were carried out using urography in the instrumental or surgical pretreatment phase, ultrasonography to check urinary dilatation and juxtavesical calculi, pyeloMR, ureteroscopic extraction, surgical operation, extracorporeal lithotripsy, and finally the expulsion of the calculi was checked. RESULTS: 81 cases of urolithiasis, 6 cases of renal abnormalities and other renal pathologies, 23 cases of extraurinary pathologies correlated to the symptoms, 5 cases of extraurinary pathologies not correlated to the symptoms and 15 normal cases, were diagnosed. The results obtained were a) a sensitivity of 96.8%, a specificity of 98.4% and a diagnostic accuracy of 97.6% in identifying ureteral calculi; b) a diagnostic accuracy of 100% in identifying urinary tract dilatation; c) a sensitivity of 100% and a specificity of 96.7% in determining the level of obstruction; d) a sensitivity of 92.9% and a specificity of 100% in determining the cause of obstruction. CONCLUSIONS: Confirming the data in the medical literature, helical CT has yielded for more reliable results than the other procedures in identifying the following: calculi, acute obstruction of the urinary tract and other urinary and extraurinary pathologies correlated to the symptoms. Therefore helical CT, where available, must be accepted as the method of preliminary evaluation in all patients with typical renal colics or with nonspecific flank pain.  相似文献   
93.
Innovative research relating oceans and human health is advancing our understanding of disease-causing organisms in coastal ecosystems. Novel techniques are elucidating the loading, transport and fate of pathogens in coastal ecosystems, and identifying sources of contamination. This research is facilitating improved risk assessments for seafood consumers and those who use the oceans for recreation. A number of challenges still remain and define future directions of research and public policy. Sample processing and molecular detection techniques need to be advanced to allow rapid and specific identification of microbes of public health concern from complex environmental samples. Water quality standards need to be updated to more accurately reflect health risks and to provide managers with improved tools for decision-making. Greater discrimination of virulent versus harmless microbes is needed to identify environmental reservoirs of pathogens and factors leading to human infections. Investigations must include examination of microbial community dynamics that may be important from a human health perspective. Further research is needed to evaluate the ecology of non-enteric water-transmitted diseases. Sentinels should also be established and monitored, providing early warning of dangers to ecosystem health. Taken together, this effort will provide more reliable information about public health risks associated with beaches and seafood consumption, and how human activities can affect their exposure to disease-causing organisms from the oceans.  相似文献   
94.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
95.
Breast biopsy consists in the collection of cells or tissue fragments from a breast lesion and their analysis by a pathologist. There are several types of breast biopsy defined on the basis of the type of needle used: fine-needle aspiration and biopsy performed with a spring-based needle. This article focuses on fine-needle aspiration performed under sonographic guidance.It is used mainly to assess cysts that appear to contain vegetations or blood or that are associated with symptoms; lesions and solid nodules that are not unequivocally benign; and axillary lymph nodes that appear suspicious on physical examination and/or sonography.In addition to distinguishing between benign and malignant lesions, ultrasound guided fine-needle aspiration also plays an important role in tumor grading and in immunocytochemical identifying specific tumor markers. This article describes the technique used and the possible causes of false negative and false positive findings. Despite its limitations, fine-needle aspiration has become a fundamental tool for the identification and preoperative management of malignant breast lesions.  相似文献   
96.
目的 评价腰椎全椎间盘置换治疗腰椎间盘源性退行性疾病的效果.方法 应用两种人工腰椎间盘移植物治疗90例108节段具有明确腰椎间盘源性退行性疾病且6个月保守治疗无效的患者,男28例,女62例;年龄25~54岁,平均39.2岁;单节段植入85例,双节段10例,三节段1例;L3-4节段6例,L4-5节段39例,L5S1A节段63例.使用Prodisc L人工腰椎间盘48节段,Maverick人工腰椎间盘60节段.手术均取腹膜后人路.术后采用改良Odom评估、Oswestry评分、VAS评分及影像学检查四种方法对症状及疼痛改善程度进行评价.结果 手术时间75~160min,平均115.5min.术中血管损伤1例.术后并发深静脉血栓1例.术后90例患者均随访12个月.随访时间分别为:术后4、6、26、52周.术后Odom评估显示:优76例,良10例,可4例,优良率95.55%.住院时间2.5~6d.平均3.4d.术后翻修2例.影像学检查:假体下沉2例,两种假体移植物均无明显向前或后迁移.结论 应用腰椎全椎间盘置换可恢复退变节段的间盘高度和神经根管的高度及前、后径,保留腰椎后柱结构的完整性和稳定性.  相似文献   
97.
98.
Pulmonary lymphangitic spread of carcinoma: appearance on CT scans   总被引:6,自引:0,他引:6  
Stein  MG; Mayo  J; Muller  N; Aberle  DR; Webb  WR; Gamsu  G 《Radiology》1987,162(2):371-375
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS.  相似文献   
99.
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
100.
Lymphokine-activated killer cells are thought to be important mediators of host tumor defense. In the present study, the cytotoxic potential of lymphokine-activated lymphocytes against different head and neck squamous cell carcinoma cell lines was investigated. Lymphokine-activated killer cells were derived from peripheral blood lymphocytes. Effector peripheral blood lymphocyte cell suspensions were incubated in the presence or absence of recombinant interleukin-2. Cytotoxicity of incubated cells or fresh peripheral blood lymphocytes was determined in a 3-hour chromium 51 release assay. Target cell lines included K562 (a natural killer-sensitive target) and the following head and neck squamous cell carcinoma cell lines: Cal 27, UMSCC-1, UMSCC-8, UMSCC-16, UMSCC-19, and UMSCC-22a. Fresh peripheral blood lymphocytes and peripheral blood lymphocytes cultured in the absence of added interleukin-2 demonstrated minimal cytotoxic effects against the squamous cell carcinoma targets. In contrast, these fresh and incubated lymphocytes showed significant cytotoxic effects against K562. Cells preincubated in the presence of interleukin-2 demonstrated a statistically significant increase in cytotoxic effects against K562 and all squamous cell carcinoma targets. These investigations support the possible role of lymphokine-activated killer cells in host defense against squamous cell carcinoma. In vitro natural killer cell activity against head and neck squamous cell carcinoma cell lines is low; however, significant lymphokine-activated killer cell cytotoxicity is present.  相似文献   
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