全文获取类型
收费全文 | 21437篇 |
免费 | 2163篇 |
国内免费 | 767篇 |
专业分类
耳鼻咽喉 | 824篇 |
儿科学 | 136篇 |
妇产科学 | 78篇 |
基础医学 | 548篇 |
口腔科学 | 53篇 |
临床医学 | 2799篇 |
内科学 | 9875篇 |
皮肤病学 | 55篇 |
神经病学 | 274篇 |
特种医学 | 855篇 |
外国民族医学 | 1篇 |
外科学 | 3487篇 |
综合类 | 2843篇 |
现状与发展 | 1篇 |
预防医学 | 432篇 |
眼科学 | 124篇 |
药学 | 1067篇 |
24篇 | |
中国医学 | 358篇 |
肿瘤学 | 533篇 |
出版年
2024年 | 62篇 |
2023年 | 588篇 |
2022年 | 865篇 |
2021年 | 1335篇 |
2020年 | 1243篇 |
2019年 | 1087篇 |
2018年 | 1141篇 |
2017年 | 903篇 |
2016年 | 1026篇 |
2015年 | 971篇 |
2014年 | 1636篇 |
2013年 | 1653篇 |
2012年 | 1292篇 |
2011年 | 1433篇 |
2010年 | 1155篇 |
2009年 | 1066篇 |
2008年 | 983篇 |
2007年 | 992篇 |
2006年 | 778篇 |
2005年 | 640篇 |
2004年 | 581篇 |
2003年 | 422篇 |
2002年 | 393篇 |
2001年 | 281篇 |
2000年 | 255篇 |
1999年 | 212篇 |
1998年 | 212篇 |
1997年 | 172篇 |
1996年 | 133篇 |
1995年 | 139篇 |
1994年 | 137篇 |
1993年 | 99篇 |
1992年 | 83篇 |
1991年 | 85篇 |
1990年 | 73篇 |
1989年 | 48篇 |
1988年 | 37篇 |
1987年 | 26篇 |
1986年 | 25篇 |
1985年 | 31篇 |
1984年 | 18篇 |
1983年 | 10篇 |
1982年 | 17篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1972年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 16 毫秒
51.
Four-hundred fifty-eight patients with cancer of the oesophagus were subjected to revisional laparotomy. Metastases into subphrenic lymph nodes were registered in 24% of the cases with a tumor in the bronchial segment; 42% with tumor in the subbronchial segment; 48% with tumor in the retropericardial segment; 71% with tumors in the sub-, intra-, and supraphrenic segments of the oesophagus. In 345 cases, laparotomy was followed by tube gastrostomy (Beck—Carrel method) with two operative deaths. Fifty-six patients in good condition with a small tumor in the middle part of the oesophagus (≤5 cm) without any abdominal metastases were subjected to primary oesophagoplasty: a 30–32-cm tube was formed out of the greater curvature of the stomach and placed retrosternally; gastrostomy was performed on the level of the thyroid cartilage (without any operative deaths). In two weeks, extirpation of the thoracic part of the oesophagus (with preoperative irradiation) was performed on patients with no abdominal metastases. Then the patients with primary oesophagoplasty were subjected to oesophago-gastrostomy of the neck. From six to 12 months following the combined treatment, the gastrostomy tube of 45 patients was lengthened to 30–32 cm and used for retrosternal oesophagoplasty (six operative deaths). Oesophagoplasty was performed on 14 patients during the extirpation of the oesophagus (six operative deaths). 相似文献
52.
三黄软膏皮肤用药毒性实验研究 总被引:2,自引:0,他引:2
为观察三黄软膏药物外用的安全性 ,进行了动物完整皮肤及破损皮肤长期接触三黄软膏 ,经皮肤渗透对局部及全身产生的毒性和反应的恢复程度 ,用三黄软膏 2g·kg-1、10g·kg-1剂量 (分别相当于 6 0kg人临床用量的 10、5 0倍 )连续对家用兔外用给药4周及停药恢复性观察 2周。结果表明给药期动物的皮肤状况、全身症状、行为活动、摄食、粪便性状、体重增长、血液学均未见明显的毒性反应 ,而高剂量组动物血液生化指标AST、ALT明显增高 ,病理组织学检查时肝水肿明显 ,可见有一定的毒性反应 ;停药期动物的血液生化指标AST、ALT肝组织病理组织学检查恢复正常 ,其他各项指标均未见明显的毒性反应 ,可见该毒性反应是可逆恢复的。表明三黄软膏在临床用药范围内连续使用是比较安全的。 相似文献
53.
Michael WJ Hii Robert N Gibson Anthony G Speer Neil A Collier Noel Sherson Cate Jardine 《Journal of Medical Imaging and Radiation Oncology》2003,47(4):393-403
We reviewed the results of percutaneous intervention of hilar biliary malignancy over a 10‐year period at a single institution: the Royal Melbourne Hospital. Ninety‐nine patients (100 treated in total) were included. Information was retrieved by retrospective examination of patient notes and radiology, combined with interviews with family and relevant physicians. Sixty‐nine patients were treated with insertion of semipermanent stents, 19 had external drain tubes, and 25 received percutaneous access for Iridium brachytherapy. Adequate drainage was achieved in 87% of the patients stented, and percutaneous access was successful in 96% of patients planned for brachytherapy. Of those patients undergoing endoprosthesis insertion, early complications occurred in 39% and late complications in 23%. Average survival for the entire patient population was 227.3 days, with a median of 167 days. Longer survival times (213 vs 142 days) and lower complication rates (44 vs 64%) are observed with metal stents in comparison with plastic stents. Percutaneous intervention is an important treatment option in hilar biliary malignancy, particularly in patients unfit for surgery. Reasonable survival with good palliation is the most common outcome, and most patients do not require further intervention. 相似文献
54.
Bulent Urman Cengiz Alatas Senai Aksoy Alp Nuhoglu Aycan Sertac Basak Balaban 《Journal of assisted reproduction and genetics》1998,15(3):125-128
Purpose:
Our purpose was to determine the feasibility and efficacy of performing testicular or epididymal sperm retrieval prior to the injection of human chorionic gonadotropin (hCG).
Methods:
This report deals with 87 sperm-positive percutaneous epididymal sperm aspiration (PESA), percutaneous testicular sperm aspiration (PTSA), or testicular sperm extraction (TESE) cycles. All sperm retrieval procedures were performed prior to administration of hCG to the women. Retrieved spermatozoa were cultured in vitro in simple medium for approximately 40 hr prior to intracyto-plasmic sperm injection.
Results:
In all but one cycle in which TESE was performed for nonobstructive azoospermia, motile sperm were available for ICSI. The overall fertilization rate was 53%. Pregnancy rate per transfer and implantation rate per embryo were 41.2 and 15.7%, respectively.
Conclusions:
Satisfactory fertilization and pregnancy rates can be achieved when PESA, PTSA, or TESE is performed prior to the injection of hCG followed by in vitro culture of spermatozoa approximately 40 hr before ICSI. Scheduling of testicular or epididymal sperm retrieval cases in this way appears to ease the workload on laboratory and operating room personnel. Furthermore, withholding hCG when sperm is absent may obviate the unnecessary risk of ovarian hyperstimulation when spermatozoa cannot be retrieved. 相似文献
55.
目的 探讨恶性输尿管梗阻(malignant ureteral obstruction,MUO)现有的临床治疗方案和经验,讨论恶性输尿管梗阻时使用经皮肾脏穿刺引流(percutaneous nephrostomy,PN)或输尿管支架置入术(ureteral stenting,US)的临床适用范围,明确2种术式在缓解恶性输尿管梗阻时肾功能损伤的有效性。方法 回顾性纳入重庆医科大学附属第一医院泌尿外科2021年1月至2023年5月诊断为恶性输尿管梗阻的患者,严格筛选纳入及排除标准后共有76例患者入组并随机分为PN组(n=22)与US组(n=54),对患者基本特征及围术期、术后半年随访数据进行病例对照研究以反映肾功能在2组中的差异,采用SPSS 21.0版本对数据进行处理分析。结果 2组患者在性别(P=0.017)、手术侧肾积水程度(P=0.000)的比较,差异有统计学意义。2组患者术前3 d比较尿素氮(P=0.002)、血肌酐(P=0.003),术后1 d尿素氮(P=0.017)、血肌酐(P=0.005),差异有统计学意义。术后3 d与术后6个月2组患者在肾功能比较中差异均无统计学意义。结论 恶性输尿管梗阻以宫颈癌多发,其次为位膀胱癌、结直肠癌等。US可选择梗阻或积水较轻、慢性输尿管梗阻、肾功能损伤较轻的患者,可作为缓解输尿管梗阻的首选治疗方案。PN临床常对中至重度肾积水、肾功能损伤较重或者急性肾功能不全的恶性输尿管梗阻患者进行治疗,可作为US失败的替代方案。 相似文献
56.
目的 回顾分析鼻内镜手术治疗慢性鼻窦炎鼻息肉的疗效及影响因素.方法 总结132例(196侧)慢性鼻窦炎鼻息肉患者的临床资料.结果 全组均随访3~12个月,治愈率72.7%,好转率21.2%,总有效率93.9%.无效6.1%.结论 鼻内镜手术治疗鼻窦炎鼻息肉刨伤小、疗效好,熟练精细的手术操作和正确的术后治疗是提高治愈率的关键. 相似文献
57.
Xinxia Zhang Wen Duan Wenbin Wei Bijuan Kuang Yunqi Zhang Xiangguang Xu Xuesong HuDepartment of Cardiology Shenzhen Futian Hospital Affiliated of Guangdong Medical College Shenzhen China 《岭南心血管病杂志(英文版)》2007,8(3):133-134
Objectives To investigate the change and clinical significance of clopidogrel on platelet membrane CD40L in coronary artery disease patients before and after percutaneous coronary intervention(PCI). Methods 30 cases who were diagnosis coronary artery diseases(CAD) by coronary angiography, mean age 56±9 years old. All the patients who had no antiplatelet aggregation contraindication, were treated with standard anti angina pectoris drugs. Before PCI, all the patients took clopidogrel 75 mg per day. Activated platelet membrane CD40L express rate was measured by flow cytometry before and after PCI 6 hours. Results Activated platelet membrane CD40L express rate were 3.73±2.15 and 2.46±0.90, respectively in 30 patients before and after PCI 6 hours. Activated platelet membrane CD40L express rate was significantly decrease after PCI 6 hours than that before PCI(P<0.01). Conclusions Clopidogrel has significance effect on platelet membrane CD40L in coronary artery disease patients undergoing PCI. Clopidogrel can suppression platelet activation and prevent thromboembolism event occurrence. 相似文献
58.
Dong Kyu Lee Jun Young Kim Yang Won Min Hyuk Lee Byung-Hoon Min Jun Haeng Lee Poong-Lyul Rhee Jae J. Kim 《Journal of thoracic disease》2022,14(6):2061
BackgroundEsophageal stricture is a major complication of endoscopic submucosal dissection (ESD) in patients with superficial esophageal cancer (SEC). Oral steroids have been used to prevent esophageal stricture in patients with more than 75% of the esophageal circumference resected. However, there are no established guidelines regarding the optimal duration of steroid use. This retrospective observational study aimed to compare the incidence of esophageal stricture according to the period of prophylactic oral steroid use and to identify the risk factors for esophageal stricture.MethodsEighty-one patients who were prescribed prophylactic steroid after undergoing ESD for SEC with more than 75% of esophageal circumference resected were enrolled. Patients were classified into the four-week steroid group (n=72) or eight-week steroid group (n=9) to compare the incidence of esophageal stricture. In addition, the patients were subdivided into those who developed esophageal stricture (n=24) and those who did not (n=57) to identify the risk factors for esophageal stricture.ResultsTwenty patients (27.8%) in the four-week oral steroid group and four patients (44.4%) in the eight-week oral steroid group developed esophageal stricture (P=0.44). The univariable analysis identified tumor size, longitudinal length of semi-circumferential resection, and proportion of circumferential resection as risk factors of esophageal stricture. The multivariable analysis identified the proportion of circumferential resection as an independent risk factor. After adjusting for the proportion of circumferential resection, the incidence of stricture was marginally higher in the eight-week steroid group [P=0.05; odds ratio (OR): 5.69; 95% confidence interval (CI): 1.01–32.15].ConclusionsEight weeks of oral steroid prophylaxis does not reduce the risk of stricture after extensive ESD more than four weeks of oral steroid prophylaxis. The proportion of circumferential resection is the strongest risk factor for stricture in patients with SEC undergoing ESD. 相似文献
59.
Background:In-stent restenosis (ISR) caused by vascular remodeling after percutaneous coronary intervention limits the long-term efficacy of this method. Salvianolate injection is now widely used in the clinical treatment of ISR. However, there is no systematic review or meta-analysis to evaluate the effects of Salvianolate injection on ISR.Methods:We will search articles in 8 electronic databases, including the Cochrane Central Register of Controlled Trials, PubMed, Embase, the Web of Science, China National Knowledge Infrastructure, the Chinese Biomedical Literature Database, Wanfang Database, and the Chinese Scientific Journal Database for randomized controlled trials of ISR treated by Salvianolate injection from their inception to February 27, 2022. The primary outcome measure will be the restenosis rate. The data meeting the inclusion criteria were analyzed by RevMan V.5.4 software. Two authors evaluated the study using the Cochrane collaborative risk bias tool. We will use a scoring method to assess the overall evidence supporting the main results.Results:This study will analyze the clinical effectiveness of Salvianolate injection in the treatment of ISR.Conclusion:The findings of this systematic review will provide evidence to evaluate the effectiveness of Salvianolate injection for the treatment of ISR.INPLASY registration number:INPLASY202220117. 相似文献
60.
Yu Diana Sanders Lynda M. Davidson III George W. R. Marvin Martha J. Ling Teck 《Pharmaceutical research》1988,5(7):457-462
Vehicle effects on the percutaneous absorption of nicardipine base, nicardipine hydrochloride, ketorolac acid, and ketorolac tromethamine were determined using the rhesus monkey as an in vivo model for human skin penetration. Vehicles investigated included blends of propylene glycol, trimethylene glycol, ethanol, Azone, Tween 20, water, and long-chain fatty acids. Formulations were prepared such that the compound dose, application area, and percentage saturation of the compound in the vehicle were held constant. Variations in absorption of the compounds were therefore attributable to vehicle effects. Each formulation was applied to three monkeys for a period of 24 hr using 10 Hill Top Chambers. Plasma samples were taken at appropriate intervals for 36 to 48 hr. The results indicated that trimethylene glycol and Tween 20 did not enhance absorption of the test compounds despite claims by other investigators. Azone and ethanol provided moderate enhancement of both the rate and the extent of absorption, while long-chain fatty acids in combination with propylene glycol significantly enhanced penetration. In general, higher fluxes were observed with the more lipophilic compounds nicardipine base and ketorolac acid as compared to the hydrochloride and tromethamine salts. 相似文献