首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   244篇
  免费   33篇
  国内免费   13篇
耳鼻咽喉   2篇
儿科学   9篇
妇产科学   32篇
基础医学   38篇
口腔科学   4篇
临床医学   30篇
内科学   51篇
皮肤病学   6篇
神经病学   3篇
特种医学   9篇
外科学   24篇
综合类   12篇
预防医学   13篇
眼科学   5篇
药学   25篇
肿瘤学   27篇
  2023年   1篇
  2022年   1篇
  2021年   2篇
  2020年   4篇
  2019年   6篇
  2018年   12篇
  2017年   6篇
  2016年   6篇
  2015年   8篇
  2014年   11篇
  2013年   9篇
  2012年   6篇
  2011年   17篇
  2010年   17篇
  2009年   17篇
  2008年   9篇
  2007年   26篇
  2006年   10篇
  2005年   7篇
  2004年   8篇
  2003年   13篇
  2002年   6篇
  2001年   7篇
  2000年   1篇
  1999年   8篇
  1998年   15篇
  1997年   7篇
  1996年   7篇
  1995年   4篇
  1994年   4篇
  1993年   5篇
  1991年   4篇
  1990年   4篇
  1989年   6篇
  1988年   3篇
  1987年   3篇
  1984年   1篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1976年   2篇
  1975年   1篇
  1968年   1篇
  1959年   1篇
排序方式: 共有290条查询结果,搜索用时 15 毫秒
61.
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量   总被引:7,自引:0,他引:7  
倪坤仪  王建  陈健  郁建  屠树滋 《药学学报》1994,29(8):624-633
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量倪坤仪,王建,陈健,郁建,屠树滋(中国药科大学210009)含牛黄的中成药种类很多,在医疗中具有广泛的用途。中药牛黄中主要成分为胆汁酸和胆红素。本文主要研究用HPLC法测定牛黄以及含牛黄中成药中胆汁酸的...  相似文献   
62.
Rat heart lipoprotein lipase was highly purified by affinity chromatography using heparin-Sepharose 4B. When extracts of acetone powder were applied to columns, lipase activity was firmly bound to the gel matrix and was later eluted with 1.5 M NaCl. At this stage the eluted enzyme was purified 1500-fold. Disc gel electrophoresis yielded a single protein band corresponding with the enzyme activity. The apparent molecular weight was 60,000. The purified enzyme was highly unstable; however, its activity could be partially stabilized by glycerol or ethylene glycol. In studying the purified enzyme we observed: (i) a cofactor in serum was required for full enzymatic activity; ApoLp-Glu could be substituted for this cofactor; (ii) ApoLp-Ser was inhibitory to lipase activity; (iii) NaCl and protamine sulfate also markedly inhibited the lipase activity; (iv) heparin stimulated the enzymatic activity.  相似文献   
63.
李智  阮英  丛华  张克义  赫梅生 《药学学报》1989,24(3):170-174
从豚鼠胃平滑肌收缩实验测得,胃底、体部纵、环肌的乙酰胆碱pD2约为6.5和4.0,阿托品的pA2约为10和8.5。实验结果提示胃平滑肌上存在高、低两种不同亲和力的毒蕈碱受体,分别与胃底、体部的纵、环肌收缩有关。又用Yamamura法对豚鼠胃平滑肌组织中的毒蕈碱受体进行了检定,测得解离常数KD值约为1.8和18 nm的两种组分。由于作用不同的蛋白质修饰剂,对这两种组分与标记配体结合的影响不同,故认为它们是亲和力不同的两种特异结合部位。  相似文献   
64.
PURPOSE: Nasopharyngeal carcinoma (NPC) has been proven as an Epstein-Barr virus (EBV)-associated cancer. Serum anti-EBV antibodies and plasma EBV DNA have been investigated as surrogate markers for NPC. A comparison of the prognostic impacts of both assays has never been reported. METHODS AND MATERIALS: Paired serum and plasma samples from 114 previously untreated NPC patients were collected and subjected to an immunofluorescence assay for immunoglobulin (Ig)A and IgG antibodies against the viral capsid antigen (VCA) and a real-time quantitative polymerase chain reaction assay for EBV DNA measurement. The effects of both assays on patient prognosis were thoroughly investigated. RESULTS: Relapsed patients had significantly higher pretreatment EBV DNA concentration than patients without relapse (p = 0.0006). No associations of VCA-IgA (p = 0.9669) or VCA-IgG (p = 0.6125) were observed between patients with and without relapse. The 4-year overall survival (60.3% vs. 93.1%, p < 0.0001) and relapse-free survival rates (54.4% vs. 77.9%, p = 0.0009) were significantly lower in patients with higher pretreatment EBV DNA load than in those with lower EBV DNA load. Patients with persistently detectable EBV DNA after treatment had significantly worse 4-year overall (30.8% vs. 84.6%, p < 0.0001) and relapse-free survival rates (15.4% vs. 74.0%, p < 0.0001) than those with undetectable EBV DNA. The VCA-IgA and VCA-IgG titer could not predict survivals (all p > 0.1). Cox multivariate analyses also showed the same results. CONCLUSION: Plasma EBV DNA is superior to serum EBV VCA antibodies in prognostic predictions for NPC.  相似文献   
65.
通过回顾香港地区肿瘤放射治疗设备、人员、技术等情况的进展,可为广大读者提供一个简单清晰的脉络,并帮助了解香港地区肿瘤放射治疗学创建与发展过程。此报告是对香港地区肿瘤放射治疗学发展的宣传与肯定,也更是为扩大放射肿瘤学科交流和发展提供契机。  相似文献   
66.
差示分光光度法测定牛黄类中成药中胆红素的含量   总被引:1,自引:0,他引:1  
本文利用胆红素溶液在光照下易氧化变色及其吸收光谱发生显著变化的性质,在波长453 nm处,测其光照前后的吸收度差值(△A),△A与胆红素溶液浓度呈线性关系,对含牛黄的中成药(六应丸,六神丸和牛黄消炎丸)中胆红素进行了定量,并对其它组分进行了光照试验,排除了光照对其它组分的影响,从而确定了此法的可行性。  相似文献   
67.
68.
The treatment of post-irradiated otitis media with effusion (OME) remains controversial. Hence the aim of this study was to understand the long-term result of management of post-irradiated OME. Eighty-five nasopharyngeal carcinoma patients with post-irradiated OME were prospectively enrolled. All were followed up with close observation and a hearing aid was advised for those with hearing loss. If patients were still bothered by aural fullness, tinnitus or hearing impairment and did not want to continue conservative treatment, tympanostomy plus aspiration was performed. Only those who had persistent OME and failed repeated tympanostomy for at least 3 months were suggested to undergo grommet insertion. After a mean follow-up of 842.1 ± 49.0 days from the completion of radiotherapy, OME was present in 45 patients (52.9%). Another 16 (18.8%) had chronic discharging ears with or without perforated eardrums. Grommets remained on the eardrums in eight patients. Among them, five were without otorrhea but discharge came from grommet tubes intermittently in three patients. Only 15 (17.6%) were free of OME, and one patient had a dry perforated eardrum. Our results showed current methods did not result in long-term resolution of some recalcitrant post-irradiated OME.  相似文献   
69.
BackgroundPrimary fallopian tube carcinoma (PFTC) is a rare tumor, and it is very difficult to diagnose preoperatively. The aims of this study were to evaluate the clinicopathologic features of primary fallopian tube carcinoma (PFTC) and to review the current available literature on PFTC.MethodsThe medical records of 16 patients who were diagnosed with PFTC at Taipei Veterans General Hospital between January 2001 and December 2011 were analyzed retrospectively.ResultsThe mean age at diagnosis was 63 years (range, 41–86 years), and the mean follow-up period was 39.8 months (range, 4.0–102.8 months). Fourteen (87.5%) patients were menopausal women. The most common clinical presentation was nonspecific pelvic pain (37.5%), followed by abnormal vaginal bleeding (31.2%), pelvic mass (18.8%), and gastrointestinal symptoms (12.5%). One patient was diagnosed with PFTC preoperatively; 11 (68.6%) patients were diagnosed as having adnexal mass of unknown origin, but primarily in the ovary. Other diagnoses included endometrial cancer, cervical cancer, colon cancer, and rectum cancer in one patient each. Three (18.8%) patients were in Stage I, two (12.5%) in Stage II, nine (56.2%) in Stage III, and two (12.5%) in Stage IV. The serous type was histologically predominant (75%), and six patients were of a high grade (37.5%). The 5-year disease-free survival rate was 73.3%.ConclusionPFTC is infrequently diagnosed preoperatively or intraoperatively due to its rarity, and has a varied and nonspecific presentation. Only 6.3% of the patients had typical symptoms suggestive of tubal carcinoma. This report may benefit surgeons by providing additional information about the clinicopathologic behavior of PFTC so that patients can be appropriately counseled.  相似文献   
70.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号