全文获取类型
收费全文 | 3157篇 |
免费 | 149篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 150篇 |
妇产科学 | 75篇 |
基础医学 | 411篇 |
口腔科学 | 35篇 |
临床医学 | 264篇 |
内科学 | 802篇 |
皮肤病学 | 74篇 |
神经病学 | 257篇 |
特种医学 | 63篇 |
外科学 | 387篇 |
综合类 | 8篇 |
一般理论 | 1篇 |
预防医学 | 117篇 |
眼科学 | 65篇 |
药学 | 167篇 |
中国医学 | 9篇 |
肿瘤学 | 426篇 |
出版年
2024年 | 2篇 |
2023年 | 20篇 |
2022年 | 36篇 |
2021年 | 57篇 |
2020年 | 49篇 |
2019年 | 58篇 |
2018年 | 80篇 |
2017年 | 58篇 |
2016年 | 52篇 |
2015年 | 83篇 |
2014年 | 116篇 |
2013年 | 115篇 |
2012年 | 200篇 |
2011年 | 225篇 |
2010年 | 135篇 |
2009年 | 130篇 |
2008年 | 207篇 |
2007年 | 218篇 |
2006年 | 203篇 |
2005年 | 198篇 |
2004年 | 208篇 |
2003年 | 184篇 |
2002年 | 177篇 |
2001年 | 56篇 |
2000年 | 29篇 |
1999年 | 36篇 |
1998年 | 31篇 |
1997年 | 36篇 |
1996年 | 38篇 |
1995年 | 29篇 |
1994年 | 20篇 |
1993年 | 16篇 |
1992年 | 21篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 22篇 |
1988年 | 17篇 |
1987年 | 16篇 |
1986年 | 6篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 13篇 |
1980年 | 10篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1975年 | 6篇 |
1973年 | 2篇 |
排序方式: 共有3316条查询结果,搜索用时 0 毫秒
121.
Ascione R Reeves BC Chamberlain MH Ghosh AK Lim KH Angelini GD 《The Annals of thoracic surgery》2002,74(2):474-480
BACKGROUND: Stroke is a rare but devastating complication after coronary artery bypass grafting (CABG) and its prevention remains elusive. We used a case control design to investigate the extent to which preoperative and perioperative factors were associated with occurrence of stroke in a cohort of consecutive patients undergoing myocardial revascularization. METHODS: From April 1996 to March 2001, data from 4,077 patients undergoing CABG were prospectively entered into a database. The association of preoperative and perioperative factors with stroke was investigated by univariate analyses. Factors observed to be significantly associated with stroke in these analyses were further investigated using multiple logistic regression to estimate the strength of the associations with the occurrence of stroke, after taking account of the other factors. RESULTS: During the study period, 4,077 patients underwent CABG and of these 923 (22.6%) had off-pump surgery. Forty-five patients suffered a perioperative stroke (1.1%). Overall there were 46 in-hospital deaths (1.1%), of whom 6 also suffered a stroke. Brain imaging of the stroke patients showed embolic lesions in 58%, watershed in 28%, and mixed in 14%. Multivariate regression analysis identified several preoperative factors as independent predictors of stroke, ie, age, unstable angina, serum creatinine greater than 150 mcg/ml, previous cerebrovascular accident (CVA), peripheral vascular disease (PVD), and salvage operation. When operative risk factors were added to the adjusted model, off-pump surgery was associated with a substantial, but not significant, protective effect against stroke (odds ratio = 0.56, 95% confidence interval 0.20 to 1.55). Survival for stroke patients was 93% and 78% at 1 and 5 years, respectively. CONCLUSIONS: Overall incidence of stroke is relatively low in our series. Age, unstable angina, previous CVA, PVD, serum creatinine greater than 150 mcg/ml, and salvage operation are independent predictors of stroke. These factors should be taken into account when informing each individual patient on the possible risk of stroke and in the decision-making process on the surgical strategy. 相似文献
122.
Imura H Modi P Pawade A Parry AJ Suleiman MS Angelini GD Caputo M 《The Annals of thoracic surgery》2002,74(6):22-2002
BACKGROUND: Cardiac troponin I (TnI) is a sensitive and specific marker of myocardial injury, but little is known about its release after complex congenital heart surgery. We investigated whether TnI correlates with early clinical outcome in neonates undergoing the arterial switch operation (ASO) for transposition of the great arteries (TGA). METHODS: Troponin I was measured serially up to 48 hours postoperatively in 31 neonates undergoing the ASO alone (simple TGA) and 9 neonates undergoing the ASO combined with other procedures (complex TGA) (eg, closure of a ventricular septal defect) and correlated with intraoperative and postoperative clinical parameters. RESULTS: There was no mortality. Troponin I peaked at either 4 or 12 hours postoperatively in all patients (median for simple TGA = 3.4 ng/mL, interquartile range 2.4 to 4.6; median for complex TGA = 4.7 ng/mL, interquartile range 3.2 to 6.8, p = 0.20). Peak TnI correlated with the durations of inotropic support (r = 0.54, p < 0.001), ventilation (r = 0.51, p < 0.01), and intensive care unit stay (r = 0.50, p < 0.01). The duration of cardiopulmonary bypass, aortic cross-clamping, and circulatory arrest did not correlate with the peak or total TnI release. The duration of aortic cross-clamping correlated poorly with the duration of inotropic support (r = 0.40, p < 0.05). The complex TGA group had longer aortic cross-clamp times, required more postoperative inotropic support, and had significantly higher total TnI release compared with the simple TGA group. CONCLUSIONS: There are weak but statistically significant correlations between peak TnI and clinical outcome. Complexity of the defect and ischemic times may be as useful to predict outcome in this group of patients. 相似文献
123.
In this report we examine the surgery of solitary thyroid nodules, outlining the operations performed and the diagnostic-instrumental procedures aimed at identifying the degree of malignancy of the lesion. If intraoperative cytological and histological examination of a nodule show that it is benign, we perform lobectomy. In a total of 400 cases, we performed 52 (13%) nodule resections, 276 (69%) hemithyroidectomies, and 72 (18%) extended resections comprising the isthmus and Laluette pyramid. Twenty-five patients (5%) were affected by differentiated cancers arising in the nodule. In this group, the carcinoma diagnosis, revealed by fine the needle aspiration and confirmed at the intraoperative examination, allowed us to perform a total thyroidectomy in a single session in 21 cases (84%); more specifically, total thyroidectomy only was performed in 14 (56%) cases, while in 7 cases (28%) a laterocervical lymph-node resection was also necessary due to the presence of lymph nodes of increased volume. We had three cases with lesions of the recurrent nerve (0.6%) and 30 with irritation of the superior laryngeal nerve (6%) which caused temporary hypoaesthesia of the larynx and hoarseness. Moreover, four patients (8%) presented temporary postoperative hypoparathyroidism. No instances of permanent hypoparathyroidism were observed. The report concludes by analysing a number of surgical techniques for the treatment of solitary thyroid nodules. 相似文献
124.
Adjuvant chemotherapy in gastric cancer: a meta-analysis of randomized trials and a comparison with previous meta-analyses 总被引:19,自引:0,他引:19
Panzini I Gianni L Fattori PP Tassinari D Imola M Fabbri P Arcangeli V Drudi G Canuti D Fochessati F Ravaioli A 《Tumori》2002,88(1):21-27
AIMS AND BACKGROUND: Up to now adjuvant chemotherapy after curative resection for gastric cancer (GC) has been considered an experimental approach. The results of existing phase III randomized trials comparing chemotherapy with control after surgery are controversial. Three meta-analyses have been published in recent years. It is likely that each of them presents a theoretical bias, mainly as regards the inclusion criteria of the trials. In this article we re-examine this potential bias, highlighting the differences between the present and past meta-analyses on adjuvant chemotherapy for GC. METHODS: Only randomized controlled clinical trials comparing systemic adjuvant chemotherapy with control after radical resection of GC were eligible. Total mortality was assessed as outcome measure of the treatment effect and a pooled odds ratio was calculated using the Peto-Mantel-Haenszel method. RESULTS: After the selection process 17 papers (18 comparisons) proved eligible for inclusion in the meta-analysis with a total of 3118 patients, of whom 1546 randomized to the treatment arms and 1572 to the control arms; 762 and 871 deaths occurred in the treatment and control arms, respectively. Statistical analysis suggests an absence of significant heterogeneity between the trials and a significant advantage in survival for adjuvant chemotherapy (pooled odds ratio, 0.72, 95% Cl, 0.62-0.84). CONCLUSIONS: Our meta-analysis would seem to indicate that adjuvant chemotherapy results in a significant survival advantage in patients with GC. However, this observation undoubtedly requires confirmation in large randomized controlled trials including cisplatin before adjuvant chemotherapy after curative resection for GC can be proposed for use in clinical practice. 相似文献
125.
Frausin F Cocchietto M Bergamo A Scarcia V Furlani A Sava G 《Cancer chemotherapy and pharmacology》2002,50(5):405-411
PURPOSE: The uptake of NAMI-A (imidazolium trans-imidazoledimethylsulphoxidetetrachlororuthenate) by KB cells in vitro was compared with the effects of this compound on the cell cycle phase distribution of the cells. METHODS: NAMI-A uptake was determined by flameless atomic absorption spectroscopy, and the cell cycle phase distribution was determined by flow cytometry. RESULTS: NAMI-A uptake was proportional to its concentration in the incubation medium. The use of a number of incubation conditions showed that NAMI-A uptake from MEM was independent of the presence of serum and dependent on the presence of amino acids in the incubation medium, and that NAMI-A uptake was markedly higher when the cells were incubated in PBS. The uptake increase observed in PBS did not occur when the cells were kept at 0-4 degrees C, suggesting the presence of active transportation of NAMI-A into cells. In addition, the presence of divalent cations such as Ca(2+) and Mg(2+), appeared to facilitate NAMI-A uptake. The anionic substance transport inhibitor probenecid significantly reduced the active transportation of NAMI-A into cells. The effects of NAMI-A on cell cycle distribution were strictly dependent on its uptake by tumour cells and not on its extracellular concentration. CONCLUSIONS: These findings suggest the interaction of NAMI-A with biological components resulting in possible consequences for the distribution of the compound itself. Furthermore, NAMI-A enters tumour cells both by passive diffusion and by active transportation. 相似文献
126.
This work represents a first attempt to refine the colony-forming unit-granulocyte/macrophage (CFU-GM) clonogenic assay by incorporating liver microsomes and co-factors as a metabolic system into the in vitro test system in response to an ECVAM recommendation. From the comparison of results obtained with the CFU-GM clonogenic assay currently used and with the new experimental protocol, different toxicity on granulocyte/macrophage precursors was demonstrated, when drugs with a known metabolism in vivo were tested. 相似文献
127.
H Gogas A Polyzos I Stavrinidis K Frangia D Tsoutsos P Panagiotou C Markopoulos O Papadopoulos D Pectasides M Mantzourani M Middleton G Vaiopoulos G Fountzilas 《Annals of oncology》2006,17(12):1835-1841
BACKGROUND: There is now increasing evidence that a constitutive expression of cyclooxygenase (COX)-2 plays a role in the development and progression of malignant epithelial tumors. Expression of COX-2 is seen in 93% of melanomas, as determined by immunohistochemistry. Temozolomide (TMZ) has demonstrated activity against melanoma and has been investigated as single agent or in combination. We designed a phase II study to assess the efficacy and toxicity of the combination of TMZ and celecoxib (a COX-2 inhibitor) in patients with advanced melanoma. PATIENTS AND METHODS: From January 2003 to July 2004, 52 patients were enrolled in the study. Nineteen patients were M1a, six M1b and 27 M1c. Patients received TMZ 200 mg/m(2) per day p.o. for 5 consecutive days every 4 weeks and celecoxib 400 mg b.i.d. p.o. for a maximum of six cycles. Celecoxib was continued until progression. RESULTS: The median age was 63 years. There were 29 males and 23 females. Among 50 assessable patients, there were 11 (21.5%) objective responses including five complete responses and six partial responses. Twenty patients (38.5%) had stabilization of their disease, and 19 (36.5%) progressed. The median time to progression was 4.6 months and the median survival 9.5 months. Twenty-two patients (41.5%) completed all cycles of treatment. Median relative dose intensity of TMZ was 0.99 (range 0.6-1.2). Most commonly seen toxic effects included anemia (27.5%), neutropenia (17.5%), thrombocytopenia (33%), nausea/vomiting (75%), gastrointestinal (52%) and fatigue (46.5%). One patient discontinued due to severe toxicity. COX-2 was determined by immunohistochemistry and was expressed in all cases. CONCLUSION: The combination of TMZ and celecoxib is safe and potentially effective in the treatment of metastatic melanoma. Randomized studies are needed to explore the role of celecoxib in combination with chemotherapy or as maintenance treatment in these patients. 相似文献
128.
Luca Gianni 《Annals of oncology》2006,17(3):357-358
129.
目的:评价早期神经功能评估在预测极低出生体重儿(VLBW)神经发育结局方面是否有效。方法:纵向观察1996—1999年连续出生于意大利北部的250例VLBW儿童(男性129例,女性121例)。当实足年龄为36月龄时检测其神经功能并按照Tardieu及国际功能分级法进行分类。结果:在校正年龄3月龄时 相似文献
130.
Lazzaro Repetto Lucia Fratino Riccardo A Audisio Antonella Venturino Walter Gianni Marina Vercelli Stefano Parodi Denise Dal Lago Flora Gioia Silvio Monfardini Matti S Aapro Diego Serraino Vittorina Zagonel 《Journal of clinical oncology》2002,20(2):494-502
PURPOSE: To appraise the performance of Comprehensive Geriatric Assessment (CGA) in elderly cancer patients (> or = 65 years) and to evaluate whether it could add further information with respect to the Eastern Cooperative Oncology Group performance status (PS). PATIENTS AND METHODS: We studied 363 elderly cancer patients (195 males, 168 females; median age, 72 years) with solid (n = 271) or hematologic (n = 92) tumors. In addition to PS, their physical function was assessed by means of the activity of daily living (ADL) and instrumental activities of daily living (IADL) scales. Comorbidities were categorized according to Satariano's index. The association between PS, comorbidity, and the items of the CGA was assessed by means of logistic regression analysis. RESULTS: These 363 elderly cancer patients had a good functional and mental status: 74% had a good PS (ie, lower than 2), 86% were ADL-independent, and 52% were IADL-independent. Forty-one percent of patients had one or more comorbid conditions. Of the patients with a good PS, 13.0% had two or more comorbidities; 9.3% and 37.7% had ADL or IADL limitations, respectively. By multivariate analysis, elderly cancer patients who were ADL-dependent or IADL-dependent had a nearly two-fold higher probability of having an elevated Satariano's index than independent patients. A strong association emerged between PS and CGA, with a nearly five-fold increased probability of having a poor PS (ie, > or = 2) recorded in patients dependent for ADL or IADL. CONCLUSION: The CGA adds substantial information on the functional assessment of elderly cancer patients, including patients with a good PS. The role of PS as unique marker of functional status needs to be reappraised among elderly cancer patients. 相似文献