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   282篇
  免费   17篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   3篇
妇产科学   5篇
基础医学   65篇
口腔科学   11篇
临床医学   17篇
内科学   54篇
皮肤病学   3篇
神经病学   46篇
特种医学   2篇
外科学   15篇
综合类   1篇
一般理论   1篇
预防医学   9篇
药学   25篇
肿瘤学   42篇
  2023年   6篇
  2022年   3篇
  2021年   15篇
  2020年   2篇
  2019年   2篇
  2018年   3篇
  2017年   3篇
  2016年   5篇
  2015年   3篇
  2014年   8篇
  2012年   6篇
  2011年   9篇
  2010年   5篇
  2009年   6篇
  2008年   14篇
  2007年   15篇
  2006年   14篇
  2005年   11篇
  2004年   10篇
  2003年   11篇
  2002年   15篇
  2001年   9篇
  2000年   18篇
  1999年   13篇
  1998年   7篇
  1997年   4篇
  1996年   9篇
  1995年   3篇
  1994年   7篇
  1993年   2篇
  1992年   4篇
  1991年   5篇
  1990年   4篇
  1989年   4篇
  1988年   2篇
  1987年   3篇
  1986年   3篇
  1985年   11篇
  1984年   2篇
  1983年   5篇
  1982年   4篇
  1981年   3篇
  1980年   2篇
  1974年   1篇
  1971年   1篇
  1970年   1篇
  1969年   2篇
  1968年   1篇
  1966年   2篇
  1965年   1篇
排序方式: 共有301条查询结果,搜索用时 16 毫秒
91.
92.
OBJECTIVE: An association between body fat distribution indices and the amount of visceral adipose tissue (AT) with blood pressure (BP) has been documented. However, most studies used casual morning BP values as the dependent variable. The aim of our study was to identify which of the obesity indices (the body mass index (BMI), waist-to-hip ratio (WHR), sagittal diameter or visceral (AT) measured by ultrasonography (US)) better correlated with BP determined by 24 h ambulatory monitoring. DESIGN: Retrospective study on obese women, outpatients at the Obesity Clinic, Internal Medicine Institute, Chieti University, Italy. SUBJECTS AND MEASUREMENTS: In fifty-one obese outpatient women, BP was determined with a single morning measurement (casual BP) and with 24 h ambulatory monitoring (ABPM). The obesity parameters were the BMI, WHR, sagittal diameter and the amount of intra-abdominal and subcutaneous fat determined by US. RESULTS: Except for the BMI, all obesity indices as WHR, sagittal diameter and visceral AT measured by US were strongly correlated with both casual and 24 h ambulatory BP values. When such parameters were evaluated in a multivariate analysis, only the WHR remained significantly related to 24 h ABPM parameters and not to casual values. CONCLUSIONS: These results suggest that a simple measure of fat distribution as the WHR could represent a good predictor of hypertension in obesity, providing that BP is measured in a more reproducible manner, such as by 24 h ambulatory BP monitoring.  相似文献   
93.
Neurological Sciences - Factitious disorder is classified as one of the five aspects of somatic symptom disorders. The fundamental element of factitious disorder is deception, i.e., pretending to...  相似文献   
94.
Neurological Sciences - The 2019 Coronavirus (SARS-CoV-2) is a novel respiratory virus which causes Coronavirus Disease19 (COVID-19). Although the predominant clinical picture of COVID-19...  相似文献   
95.
In this study we have analyzed the in vitro cell-mediated cytotoxicity of immune peritoneal exudate cells (PEC), elicited in syngeneic mice against the MCA-induced, TSTA-bearing BALB/c fibrosarcomas CA-2, GI-17 and C-3. The 4 h 51Cr-release assay showed the immune PEC effectors to be specifically cytotoxic to fibrosarcoma used for the immunization, but not to other syngeneic MCA-induced tumors or normal fibroblasts. Cold target inhibition experiments on CA-2 cells confirmed the specificity of the reaction. When PEC, lymph-node and spleen cells from BALB/c anti-CA-2 mice were compared for anti-tumor activity, only PEC were found to kill tumor cells significantly. PEC effectors did not have a significant level of NK or NC activities since they were unable to destroy YAC-1 target and the PEC-mediated anti-tumor activity was not inhibited by unlabelted YAC-1 or WEHI-164 tumor cells. PEC anti-CA-2 were analyzed for the expression of T-cell markers by anti-Thy 1.2, anti-Ly 1.2 and Ly 2.2 monoclonal antibodies. Anti-tumor specific effector cells were identified as mature T cells since they were not adherent to plastic and showed Thy l.2+, Ly 1.2? and Ly 2.2+ phenotypes. In addition, anti-H-2Kd but not anti-H-2Dd alloantiserum added to target cells, blocked CA-2 tumor lysis, thus supporting the conclusion that the T-cell response against TSTA is H-2 restricted.  相似文献   
96.
The H-2b-negative B78HI clone (derived from B16 melanoma) was transfected with the H-2Kb gene; 4 cell clones expressing membrane H-2Kb antigens and 2 control clones (transfected with pSV2neo alone) were used for studies of metastatic ability, immunogenicity, NK sensitivity and homotypic adhesion. The experimental metastatic capacity of H-2Kb transfectants in syngenic mice was greatly diminished in comparison with control and parent cells. Both immune-mediated and intrinsic properties of transfectants correlated with their lower metastatic ability. A cell-mediated cytotoxic response was induced by repeated in vivo immunizations of syngeneic mice followed by in vitro restimulation of effectors when transfectants (but not controls) were used as immunizers and as targets. Moreover, homotypic adhesion of H-2Kb transfectants was significantly lower than that of controls. Sensitivity to NK cells of transfectants was not decreased in comparison to H-2-negative controls. It is known that in vitro treatment with IFN-gamma of H-2-positive B16 melanoma cells induces a simultaneous increase in H-2 expression and in experimental metastasis; treatment of H-2Kb transfectants with IFN-gamma induced a higher Kb expression, but no increase in metastatic ability, thus suggesting that the IFN-sensitive component that mediates enhancement of metastasis is not H-2Kb.  相似文献   
97.
A three-generation BO family is presented: the proband showed, in addition to branchio-oto malformations, a severe condition with growth retardation, mandibular hypoplasia and vertebral anomalies resembling the oculo-auriculo-vertebral (OAV) phenotype. This family study supports the hypothesis of Rollnick and Kaye that the OAV spectrum may represent, in some cases, an extreme component of the BOR syndrome. The finding has relevant implications for genetic counselling regarding both conditions.  相似文献   
98.
Two human cancer cell lines (MA 2 and MA 3) were established from pleural effusions of infiltrating ductal carcinomas of the breast.The lines were maintained in continuous monolayer culture withdoubling times of 70 (MA 2) and 78 (MA 3) hr for more than two years and possessed extensively rearranged abnormal karyotypeswith modal chromosome number of 83 (MA 2) and 81 (MA 3) and DNA index values of 1.65 and 1.77, respectively. No amplifications or rearrangements were evident in the c-myc, int-2, c-erb B2, c-Ha-ras, or hst 1 genes in MA 2 and MA 3 cell lines.The clinical histories of the patients from whom the cell lines were derived are reported and compared with the results observed inthe cell lines in vitro. The presence of CEA, CA 15-3, and MCA tumormarkers observed in the primary tumor tissues was retained by the established cell lines. While the primary tumor tissueswere ER+/PgR borderline + (MA 2) and ER–/PgR+(MA 3), the MA 2 line was ER+/PgR– and the MA 3 line remained ER–/PgR+.The MDR P-glycoprotein was not expressed either in primary tumor tissues or in the respective cell lines. High expression of cytokeratins7, 18, and 19 was evident by immunohistochemical analysis in each cell line, whereas cytokeratins 8 and 17 were poorly or not at allexpressed. The treatment history of the patients fromwhom the cell lines were derived involved CMF followed six monthslater by novantrone and cisplatin plus VP 16 (MA 2) and FEC followedfour years later by CMF (MA 3). The chemosensitivitypattern assay of the cell lines indicated that the MA 2 linewas sensitive to doxorubicin, cisplatin, and vinblastine, whereas theMA 3 line was sensitive to doxorubicin and cisplatin.The characteristics of these cell lines indicate them to be a goodexperimental model to investigate breast cancer biology and anticancerdrug response.  相似文献   
99.
The expression of activated ras oncogenes was found to be associated with that of tumour-specific transplantation antigens in mouse tumours, which can be cured by adoptive immunotherapy with T lymphocytes and interleukin-2 (IL-2). A similar association is here proposed to exist between RAS oncogene activation (mutation) in human melanoma and susceptibility of these tumours to the lytic action of activated lymphocytes (both lymphokine-activated killers and cytotoxic T cells) which have been used, along with IL-2, in the adoptive immunotherapy of advanced melanomas. The limited clinical response (15-25%) of melanoma patients to different immunological therapies is, therefore, considered to be due to a similar frequency of immunogenic, RAS+ melanomas. The authors thus suggest that RAS activation might be a marker of immunogenicity and that only the subset of melanoma cells expressing activated RAS will in turn possess tumour antigens which can be the target of immunotherapeutic, activated lymphocytes. It is then predicted that RAS+ melanomas will be more susceptible to adoptive immunotherapy than RAS-counterparts.  相似文献   
100.
Excessive non-enzymic glycation of proteins alters their physicochemical properties, with possible pathological effects. We investigated the in vitro inhibition of protein glycation by D-lysine--an isomer not incorporated into mammalian proteins but possessing the same chemical characteristics as L-lysine. Glucose incorporation was studied as follows: (a) human albumin, IgG, collagen, and isolated glomerular basement membrane were incubated for 20 days with D-glucose (5.0, 10.0, and 20.0 mmol/L) in the presence of D-lysine at 1/10 the sugar concentration; (b) albumin was incubated in similar glucose concentrations but with a constant amount (2.0 mmol/L) of D-lysine; (c) albumin and IgG were incubated for 10 days in buffer containing glucose (10 mmol/L) and increasing concentrations of D-lysine (0.25, 0.5, 1.0, 2.0, and 4.0 mmol/L); (d) inhibition specificity was tested by treating albumin as in c but with glycerol present rather than D-lysine. In addition, we measured ketoamine after incubating albumin (50 g/L) in 10 mmol/L glucose for 10 days in the presence of D-lysine (0.25, 0.5, 1.0, and 2.0 mmol/L). The results show that (a) the amount of glucose bound to the four proteins was significantly (P less than 0.05) decreased in the presence of D-lysine at the higher concentrations of glucose; (b) the lower the glucose concentration, the higher was the inhibitory effect of D-lysine; (c) the inhibition of glucose incorporation into proteins correlated directly with the concentration of D-lysine; (d) no inhibition was observed with glycerol. Ketoamine decreased with increase in D-lysine (P less than 0.01). The effective diminution of non-enzymatic glycation by D-lysine highlights its potential use in vivo.  相似文献   
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