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   256篇
  免费   13篇
  国内免费   19篇
耳鼻咽喉   1篇
儿科学   11篇
妇产科学   4篇
基础医学   32篇
口腔科学   8篇
临床医学   21篇
内科学   40篇
皮肤病学   8篇
神经病学   6篇
特种医学   42篇
外科学   25篇
综合类   20篇
预防医学   13篇
药学   41篇
中国医学   1篇
肿瘤学   15篇
  2023年   1篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   3篇
  2017年   4篇
  2016年   3篇
  2015年   9篇
  2014年   10篇
  2013年   13篇
  2012年   6篇
  2011年   4篇
  2010年   12篇
  2009年   12篇
  2008年   7篇
  2007年   17篇
  2006年   20篇
  2005年   10篇
  2004年   9篇
  2003年   10篇
  2002年   5篇
  2001年   10篇
  2000年   6篇
  1999年   6篇
  1998年   19篇
  1997年   15篇
  1996年   10篇
  1995年   6篇
  1994年   11篇
  1993年   10篇
  1992年   1篇
  1991年   3篇
  1990年   1篇
  1989年   5篇
  1988年   2篇
  1987年   2篇
  1986年   2篇
  1985年   4篇
  1984年   4篇
  1983年   5篇
  1982年   3篇
  1981年   1篇
  1980年   1篇
  1977年   3篇
排序方式: 共有288条查询结果,搜索用时 15 毫秒
101.
ObjectiveTo study anxiolytic property of hydro alchohol extract and to estimate polyphenols present in the extract by HPLC.MethodsTo evaluate anxiolytic property two animal models were used viz. Elevated T maze and hyponeophagia. Diazepam (1 mg/kg body wt.) served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and locomotor and anxiolytic activities were performed. Polyphenols was estimated using HPLC.ResultsThe HPLC analysis of the polyphenols revealed the presence chlorogenic acid, vanillin, epicatechin, caffeic acid, rutin hydrate, sinapic acid, quercetin-3-rhamnoside, p-coumeric acid and quercitin. Time spent and number of entries into the open arm was improved in 30 days treated animals than that of 15 days treated groups, 200 and 400 mg/kg body weight treated group showed significant results when comparing with the control group.ConclusionsThe hydro alcohol extract rich in Polyphenols and other secondary metabolites is a potent anxiolytic agent.  相似文献   
102.
Poor women are often compelled to accept jobs that jeopardise their health and their social reputations. Cantineras are recently immigrated Latinas employed in working-class Latino bars (cantinas) where they are hired as waitresses to earn sales commissions from beer purchased for them by male clients seeking female companionship. Narratives solicited from 31 cantineras revealed the work subculture of local cantinas, where drinking is a primary work obligation and where men expect sexual favours as a quid pro quo for beers they buy. This paper describes strategies that cantineras adopt to downplay their drinking and to disguise sex-trading practices. This distortion or ‘misrecognition’ of work-related practices functions to manage cantineras' fear of being stigmatised as workers and devalued as individuals. We argue that misrecognition in this context represents more than simple attempts at denial or to uphold a public image. Rather, it is a strategy employed by cantineras in order to function adaptively under oppressive work circumstances. Confronting stigma leads cantineras to adopt social and cognitive strategies that, while minimising social damage in the near term, can lead to devastating health and social consequences over time.  相似文献   
103.
Poor women are often compelled to accept jobs that jeopardise their health and their social reputations. Cantineras are recently immigrated Latinas employed in working-class Latino bars (cantinas) where they are hired as waitresses to earn sales commissions from beer purchased for them by male clients seeking female companionship. Narratives solicited from 31 cantineras revealed the work subculture of local cantinas, where drinking is a primary work obligation and where men expect sexual favours as a quid pro quo for beers they buy. This paper describes strategies that cantineras adopt to downplay their drinking and to disguise sex-trading practices. This distortion or 'misrecognition' of work-related practices functions to manage cantineras' fear of being stigmatised as workers and devalued as individuals. We argue that misrecognition in this context represents more than simple attempts at denial or to uphold a public image. Rather, it is a strategy employed by cantineras in order to function adaptively under oppressive work circumstances. Confronting stigma leads cantineras to adopt social and cognitive strategies that, while minimising social damage in the near term, can lead to devastating health and social consequences over time.  相似文献   
104.
105.
To prospectively compare the feasibility, safety and diagnostic role of carbon dioxide (CO2) digital subtraction angiography (DSA) using a ‘home made’ delivery system with iodinated contrast medium (ICM) DSA in the evaluation of peripheral arterial occlusive diseases (PAOD) of lower limbs. Twenty‐one patients (27 limbs; all men; mean age, 47.6 years) who presented with PAOD of lower limbs underwent DSA using both intra‐arterial CO2 and ICM. Conventional ICM DSA was performed first and used as gold standard. Carbon dioxide was then injected by hand using a locally improvised home made plastic bag delivery system. Patient tolerance was assessed subjectively. Arteries from aortic bifurcation to the ankle were independently evaluated by two radiologists and graded for stenosis using a five‐point scale. For each patient, the quality of CO2 DSA images were compared with the corresponding images of ICM DSA and an overall grade of ‘good’, ‘acceptable’ or ‘poor’ was assigned. Cohen’s kappa coefficient was used to determine inter‐observer agreement. Carbon dioxide opacified 86.2% (188/195) of major arteries and depicted stenosis adequately in 84.5% (191/226) of arterial segments. A good or acceptable image quality of CO2 DSA was obtained in over 95% of patients. Infrapopliteal arteries were inadequately visualized. Mild pain was seen in six (28.6%) patients with both contrast agents; one patient developed severe pain during CO2 DSA. Inter‐observer agreement was good (k > 0.75) at 70% of the segments. Administration of CO2 into lower limb arteries is well tolerated. Carbon dioxide DSA using the locally improvised home made delivery system is a feasible and safe alternative to ICM DSA in the evaluation of PAOD. It provides adequate imaging of arteries of lower extremities except infrapopliteal segments.  相似文献   
106.
107.
Evaluation of papillary lesions of the breast can be difficult, and in core needle biopsy specimens, accurate diagnosis is challenging. Initial studies suggested that all papillary lesions revealed by core biopsy required surgical excision. Recent data suggest that only papillary lesions with atypical ductal hyperplasia (ADH) revealed by core biopsy need surgical excision. We evaluated our experience at the University of Washington Medical Center, Seattle, with papillary lesions with and without ADH on core biopsy to determine whether diagnostic accuracy can be achieved. In 51 core biopsy specimens, we evaluated the presence or absence of ADH: 25 were benign papillomas; 26 were papillomas with ADH. Surgical follow-up was available for 36 cases (11 papillomas and 25 papillomas with ADH). Clinical (radiologic) follow-up was available in 5 papilloma cases (average follow-up, 35.6 months). Follow-up revealed that all papillomas on core biopsy were benign. Excisional biopsy revealed ductal carcinoma in situ or invasive carcinoma in 12 (48%) of 25 papillary lesions with ADH. Benign papillomas can be adequately diagnosed with core biopsy. All papillary lesions with ADH require surgical excision owing to the high rate of associated neoplasia.  相似文献   
108.
Although recent studies have suggested that p16(INK4a) may be a useful surrogate biomarker of cervical neoplasia, Ki-67 and human papillomavirus testing have also been shown to be useful in detecting neoplasia. To help delineate the utility of p16(INK4a), biopsy samples (n = 569: negative, 133; reactive, 75; atypical, 39; low grade, 76; moderate, 80; and severe intraepithelial neoplasia, 113; also, squamous cell carcinoma, 46; adenocarcinoma, 7) were analyzed by immunohistochemistry for expression of p16(INK4a) and Ki-67 (n = 432), as well as by in situ hybridization for human papillomavirus Type 16 (n = 219). Testing for high-risk human papillomavirus types by polymerase chain reaction and HybridCapture2 was performed on concurrent cervical swab specimens. Recuts of the original blocks were reexamined (n = 198). Endometrial biopsies (n = 10) were also analyzed for p16(INK4a) expression. Degree of p16(INK4a) and Ki-67 expression correlated with degree of cervical neoplasia (P <.001) and with presence of high-risk human papillomavirus types (P <.001). There was no relationship between p16(INK4a) overexpression and inflammation or hormonal status. Ki-67 expression correlated with inflammation (P = 0.003) and was expressed in more reactive and atypical lesions than p16(INK4a) (P = 0.008). Probes for human papillomavirus 16 stained 54% of cervical neoplastic lesions; the degree of staining correlated significantly with degree of neoplasia (P <.001) and p16(INK4a) staining (P <.001). Interobserver reproducibility was substantial for p16(INK4a) and Ki-67 interpretation (weighted kappa: 0.74 and 0.70, respectively). Expression of p16(INK4a) was observed in all endometrial biopsies. Compared with Ki-67 expression and detection of high-risk human papillomavirus, p16(INK4a) was less likely to be positive in samples from women with negative, reactive, and atypical biopsies. Although expression of p16(INK4a) in endometrial epithelium may be problematic in terms of screening, the potential of p16(INK4a) as a screening test warrants investigation.  相似文献   
109.
We sought to determine the prevalence of androgen receptor (AR) expression in a predominantly estrogen receptor (ER)-negative subset of breast cancers and delineate the immunohistochemical and clinical associations, including whether AR expression has prognostic significance in ER-negative tumors. We identified 69 ER-negative and 19 ER-positive breast cancer cases with concurrent immunohistochemical prognostic panels (ER, PR, HER-2/neu, Ki-67, and p53); immunohistochemical analysis was performed for AR using standard techniques. Clinical data were extracted from medical records. chi 2 tests were used to assess associations between variables. AR was found in 49% (34/69) of ER-negative and 89% (17/19) of ER-positive cases. In ER-negative tumors, AR was associated with increased age (P = .02), postmenopausal status (P < .001), tumor grade (P = .03), tumor size (P = .03), and HER-2/neu overexpression (P = .003). In ER-positive tumors, AR was associated with progesterone receptor expression (P < .03). In univariate analysis of ER-negative tumors, patients with AR-positive tumors had significantly better disease-free survival (P = .049). AR is expressed in a significant number of ER-negative cases and shows significant associations with important clinical and pathologic prognostic factors.  相似文献   
110.
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