全文获取类型
收费全文 | 2580篇 |
免费 | 151篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 56篇 |
妇产科学 | 132篇 |
基础医学 | 247篇 |
口腔科学 | 72篇 |
临床医学 | 212篇 |
内科学 | 536篇 |
皮肤病学 | 30篇 |
神经病学 | 184篇 |
特种医学 | 114篇 |
外国民族医学 | 3篇 |
外科学 | 470篇 |
综合类 | 28篇 |
一般理论 | 3篇 |
预防医学 | 113篇 |
眼科学 | 107篇 |
药学 | 172篇 |
中国医学 | 2篇 |
肿瘤学 | 234篇 |
出版年
2024年 | 3篇 |
2023年 | 25篇 |
2022年 | 55篇 |
2021年 | 113篇 |
2020年 | 78篇 |
2019年 | 105篇 |
2018年 | 160篇 |
2017年 | 111篇 |
2016年 | 87篇 |
2015年 | 90篇 |
2014年 | 123篇 |
2013年 | 145篇 |
2012年 | 225篇 |
2011年 | 220篇 |
2010年 | 140篇 |
2009年 | 92篇 |
2008年 | 161篇 |
2007年 | 155篇 |
2006年 | 126篇 |
2005年 | 119篇 |
2004年 | 109篇 |
2003年 | 113篇 |
2002年 | 98篇 |
2001年 | 12篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 12篇 |
1995年 | 13篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有2744条查询结果,搜索用时 10 毫秒
161.
Tobacco use by university students,Lebanon, 2001 总被引:2,自引:0,他引:2
Tamim H Terro A Kassem H Ghazi A Khamis TA Hay MM Musharrafieh U 《Addiction (Abingdon, England)》2003,98(7):933-939
Aims The objective was to determine the prevalence of smoking [cigarettes and/or narghile (i.e. water‐pipe)] among university students and to examine multiple correlates. Design Cross‐sectional. Setting Beirut, Lebanon. Participants A proportionate random sample of 1964 students from public and private universities in Beirut, Lebanon. Measurements Participants completed a self‐administered anonymous questionnaire that included demographic and scholastic items and health behavioral aspects, including smoking, alcohol, physical activity, weight control measures and seat belt use. Findings The overall prevalence of smoking was 40% (21.1%, 7.6% and 11.3% of the students were smoking only narghile, only cigarettes and both cigarettes and narghile, respectively). Regression analyses showed that males, those of non‐Lebanese origin, pursuing undergraduate degrees, performing risky weight control measures and drinking excessive amounts of alcohol had increased odds of smoking cigarettes. Also, age, high level of paternal education and field of study were significant predictors. Narghile smoking was significantly higher among males who drank excessive alcohol. Conclusions The authors advocate a collaborative effort to alleviate the consequences of smoking among university students. 相似文献
162.
Four-step local anesthesia and sedation for thoracoscopic diagnosis and management of pleural diseases 总被引:2,自引:0,他引:2
STUDY OBJECTIVES: Most thoracic surgeons perform thoracoscopy under general anesthesia using a double-lumen endotracheal tube. We describe our own technique for performing thoracoscopy under local anesthesia and sedation. DESIGN, SETTING, PATIENTS: Forty-five patients underwent the procedure under local anesthesia and sedation (mean age, 64 years; age range, 40 to 92 years). A known history of cancer was present in 12 patients. American Society of Anesthesiology score was I in 1 patient, II in 16 patients, III in 22 patients, IV in 5 patients, and V in 1 patient. Premedication was comprised of droperidol, 5 mg, and atropine, 0.5 mg, administered 20 min before the scheduled operating room time. Sedation was maintained by diazepam injection, 3 mg. Four-step local anesthesia in the planned intercostal space using 10 mL of ropivacaine, 7.5 mg/mL, was performed. RESULTS: Mean operative time was 45.7 min (range, 20 to 90 min); mean time of anesthesia was 71.3 min (range, 30 to 150 min). Among patients with pleural effusion, 23 effusions were simple and 16 effusions were complex. Talc was administrated in 28 patients. Complications were intraoperative bleeding (one patient), hyperpyrexia (eight patients), and atrial fibrillation (two patients). The mean time for removal of the chest drain was 5.6 days (range, 2 to 13 days). Postoperative hospital stay was 6.4 days (range, 2 to 14 days). No hospital mortality occurred. Follow-up is complete in all patients (mean, 92.8 days; range, 31 to 270 days). CONCLUSION: Four-step local anesthesia and sedation is a simple and effective method of performing a video-assisted thoracic procedure to diagnose and treat simple thoracic pathologies. 相似文献
163.
Bismar TA Lewis JS Vollmer RT Humphrey PA 《The American journal of surgical pathology》2003,27(4):432-440
The capacity of perineural invasion by carcinoma in prostate needle biopsy tissue to independently predict pathologic stage in radical prostatectomy tissues remains uncertain. We sought to determine, in a prostate specific antigen-based screening population, the ability of needle biopsy histologic grade, tumor extent, and perineural invasion to independently predict pathologic stage and margin status in the whole prostate gland. Perineural invasion, Gleason grade, percentage Gleason pattern 4/5 carcinoma, and multiple measures of needle biopsy tumor extent, including number of positive cores, percentage of positive cores, total percentage of carcinoma, greatest percentage of carcinoma in a single core, and total carcinoma length in millimeters, were captured for 215 men from a prostate specific antigen-based screening program diagnosed with prostate cancer in a median of six procured needle biopsy cores. Pathologic stage and surgical margin status were evaluated in corresponding completely embedded radical prostatectomy specimens. A logistic regression model was used to relate the endpoints of extraprostatic extension by carcinoma and/or positive margins to needle biopsy tissue findings. In univariate analyses, total percentage of carcinoma (p = 0.003), greatest percentage of carcinoma in a single core (p = 0.004), total tumor length in millimeters (p = 0.009), and fraction of positive cores (p = 0.02) were all significantly associated with extraprostatic (pT3) carcinoma, whereas all five measures of carcinoma extent in needle biopsy tissue were related to positive margins. Correlation coefficient determinations showed that all five measures of needle biopsy carcinoma extent were highly interrelated. In multivariate analyses, total percentage of carcinoma was significantly related to pathologic T stage (p = 0.003) and positive margins (p = 0.0002). In a multivariate model with the radical prostatectomy whole gland endpoint of either pT3 disease or positive margins, fraction of positive cores (p = 0.00001) was the only variable with significant predictive value. Perineural invasion by carcinoma in needle biopsy tissue was detected in 11% of cases. Neither presence nor absence of perineural carcinoma nor number nor percentage of positive nerves related to pathologic stage in univariate or multivariate analyses. Amount of carcinoma in prostate needle biopsy tissue, using multiple measurements but not perineural invasion, is a significant histologic attribute predictive of pathologic stage and margin status for men with prostate specific antigen screening detected prostatic carcinoma. Reporting of several measures of carcinoma extent in needle biopsy tissue is recommended. 相似文献
164.
165.
Thameur H Abdelmoula S Chenik S Bey M Ziadi M Mestiri T Mechmeche R Chaouch H 《World journal of surgery》2001,25(1):58-67
apd: 18 December 2000 相似文献
166.
In Vitro Evaluation of a New Rotational Thrombectomy Device: The Straub Rotarex Catheter 总被引:4,自引:0,他引:4
Zana K Otal P Fornet B Forrai G Chabbert V Smayra T Joffre F Rousseau H 《Cardiovascular and interventional radiology》2001,24(5):319-323
Purpose: To evaluate the efficacy of a new rotational thrombectomy device, and the procedure-related risk of particle embolization.
Methods: The experiments were performed in transparent silicone tubes. The conditions of flow were as close as possible to physiological
parameters. Distal embolization was detected by a mesh of nylon filters.
Results: The Straub Rotarex catheter was able to remove all clots. The mean number of migrating particles larger than 1000 μm was
0.17 (± 0.38), the mean number of 400–1000 μm migrating particles was 1.08 (± 1.04). The mean intervention time was 67 (±
37) sec. The mean volume of collected liquid was 96.6 (± 24.7) ml.
Conclusion: The in vitro results suggest that the Straub Rotarex catheter is able to remove large volumes of thrombus with a limited
risk of embolization. The main limitation of our model is the absence of adhesion of the clot to the tube. 相似文献
167.
Tarek Shokeir Ahmed Badawy Hatem Abo-Hashem 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2008,12(3):267-272
OBJECTIVE: Abdominal wall adhesions at laparoscopy may predispose infertile patients to access-related injuries and increase the complexity of the procedure. We have observed concern from referring physicians regarding the safety of surgical laparoscopy in infertile patients who previously underwent surgery because of the risk of abdominal adhesions. To assess the risk of intraabdominal adhesions at laparoscopy, a retrospective cohort study was performed. METHODS: All infertile patients who underwent a reproductive laparoscopic procedure in a 6-year period at our institution were included in this study. A chart review was performed to obtain demographic/surgical data and identify preoperative risk factors for intraabdominal adhesions. Operative videotapes were reviewed to determine the presence and location of adhesions. Standard statistical analyses were performed. RESULTS: During the study period, 254 infertile patients underwent reproductive surgical laparoscopy, and videotapes on 164 (65%) were available for review. A total of 88 patients (54%) were identified with preoperative risk factors for intraabdominal adhesions (group 1), while 76 (46%) had no risk factors (group 2). The relative risk of adhesions was 1.34 (95% CI, range 0.89 to 2.01, P=0.18) when risk factors were identified. There were no differences in the groups regarding patient age, operative time, access technique, conversion to open surgery, or complications. Estimated blood loss was significantly higher in group 2, likely due to the predominance of laparoscopic surgery for ovarian endometriomata and complexity of the cases rather than the presence or absence of intraabdominal adhesion risk factors. CONCLUSIONS: No difference existed in the risk of intraabdominal adhesions in infertile patients with and without identifiable preoperative risk factors. Preoperative risk factors for intraabdominal adhesions should not contraindicate the surgical laparoscopic approach for reproductive procedures. 相似文献
168.
André O von Bueren Tarek Shalaby Julia Rajtarova Duncan Stearns Charles G Eberhart Lawrence Helson Alexandre Arcaro Michael A Grotzer 《BMC cancer》2007,7(1):19
Background
With current treatment strategies, nearly half of all medulloblastoma (MB) patients die from progressive tumors. Accordingly, the identification of novel therapeutic strategies remains a major goal. Deregulation of c-MYC is evident in numerous human cancers. In MB, over-expression of c-MYC has been shown to correlate with anaplasia and unfavorable prognosis. In neuroblastoma – an embryonal tumor with biological similarities to MB – the quassinoid NBT-272 has been demonstrated to inhibit cellular proliferation and to down-regulate c-MYC protein expression. 相似文献169.
Abdel Halim A. Moustafa Ehab M.M. Ali Tarek M. Mohamed Heba I. Abdou 《European Journal of Internal Medicine》2009,20(7):703-708
BackgroundThe liver metabolizes the thyroid hormones and regulates their systemic endocrine effects so liver disease could affect thyroid hormone metabolism. Oxidative stress could play a role in the pathogenesis and progression of liver diseases. The objective of this study was to investigate serum levels of oxidative stress and antioxidant in liver diseases as prognostic markers and know the importance of these antioxidants level in relation to thyroid hormones.MethodsSerum nitric oxide (NO), malondialdehyde (MDA) and triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH), apolipoprotein-1 (APOA1) levels and erythrocyte reduced glutathione (GSH) level and glutathione peroxidase (GSHPx) and glutathione reductase (GR) activities were determined in 20 control subjects, 13 patients with non-alcoholic steatohepatitis (NASH), 18 patients with chronic HCV, 17 patients with compensated cirrhotic HCV and 42 patients with decompensated cirrhotic HCV.ResultsCirrhotic patients with HCV had higher NO and MDA levels while lower T3 and erythrocyte GSH levels, and GSHPx activity than the chronic. Serum T3 showed negative correlation with serum NO and MDA whereas positive correlation with APOA1, GSH, and GSHPx in cirrhotic patients with HCV.ConclusionThe measurement of the total T3, NO, MDA, GSH reduced and GSHPx as biomarkers for liver diseases might be a beneficial tool, helping in monitoring the state of liver disease patients. 相似文献
170.
Charles de Mestral Tarek Razek Kosar Khwaja Paola Fata 《European journal of trauma and emergency surgery》2008,34(6):595-600
Background Extrahepatic biliary tract injuries following blunt abdominal trauma are very rare and pose a diagnostic and therapeutic challenge.
Case Report We report a case of blunt liver injury with left extrahepatic duct transection following a motor vehicle collision. Technetium
99m dimethyliminodiacetic acid scan confirmed a bile leak and endoscopic retrograde cholangiopancreatography (ERCP) diagnosed
the injury of the left extrahepatic duct. Management was initially conservative, consisting of external drainage along with
trials of stent placement. Ultimately, partial left hepatectomy was required to definitively treat the injury.
Conclusion In the setting of suspected biliary tract injury, early ERCP is essential to localize a leak and guide management decisions.
In the event of a confirmed bile leak, a trial of nonoperative management consisting of endoscopic ductal decompression along
with percutaneous drainage may initially be warranted although is not always successful. 相似文献