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   211篇
  免费   2篇
儿科学   1篇
妇产科学   3篇
基础医学   23篇
口腔科学   20篇
临床医学   15篇
内科学   81篇
皮肤病学   1篇
神经病学   7篇
特种医学   14篇
外科学   34篇
综合类   1篇
药学   7篇
肿瘤学   6篇
  2023年   1篇
  2022年   2篇
  2021年   2篇
  2020年   1篇
  2018年   2篇
  2017年   3篇
  2016年   2篇
  2015年   2篇
  2014年   3篇
  2013年   4篇
  2012年   4篇
  2011年   5篇
  2010年   5篇
  2009年   3篇
  2008年   4篇
  2007年   4篇
  2006年   6篇
  2005年   7篇
  2004年   8篇
  2003年   12篇
  2002年   5篇
  2001年   10篇
  2000年   11篇
  1999年   4篇
  1998年   2篇
  1997年   2篇
  1995年   1篇
  1994年   2篇
  1993年   2篇
  1992年   6篇
  1991年   7篇
  1990年   16篇
  1989年   15篇
  1988年   8篇
  1987年   8篇
  1986年   5篇
  1985年   11篇
  1984年   8篇
  1983年   3篇
  1982年   3篇
  1977年   1篇
  1974年   1篇
  1973年   1篇
  1956年   1篇
排序方式: 共有213条查询结果,搜索用时 15 毫秒
1.
To evaluate the effect of UFT, a mixture of ftorafur and uracil in a ratio of 1:4, in preventing postoperative recurrence of bladder cancer, we performed a randomized controlled study with a non-medication group as control. UFT was given orally 400 mg a day for 6 months. Of 111 patients, 56 were given UFT and 55 were followed up without any medication. The non-recurrence rate in the group treated with UFT was 62.8% after 1 year and 36.3% after 2 years of follow up, and that of the control group was 45.7% and 39.5%, respectively. The rate of non-recurrence in the UFT group was significantly higher (p less than 0.05) than that of the control group during the period of follow up for 2 years. The incidence of side effects was 6.8% in UFT patients. These results indicate the clinical usefulness of prophylactic administration of UFT for bladder cancer patients.  相似文献   
2.
We previously reported the expression profiles of 9 cytochrome P450 isozymes (CYPs) proteins and those of 40 CYPs genes in pregnant rat's liver, placenta and fetal liver after treatment with pregnenolone-16alpha-carbonitrile (PCN) or phenobarbital (PB). This study was carried out focusing on the gene expression profiles of Phase II drug metabolizing enzymes, Glutathione S-transferase isozymes (GSTs) and UDP-glycosyltransferase isozymes (UDPGTs). Fischer 344 (F344) pregnant rats were daily treated intraperitoneally with 50 mg/kg of PCN or 80 mg/kg of PB from 13 to 16 days of gestation (DG). They were sacrificed on 17 DG, and microarray analysis using Affymetrix Rat Expression Array 230 A was performed. Among 16 GSTs genes examined in this study, 7 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 8 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. On the other hand, among 11 UDPGTs genes examined, 5 genes were significantly induced in dam's liver and 3 genes in fetal liver, respectively, in the PCN-group, while 5 genes were significantly induced in dam's liver and 1 gene in fetal liver, respectively, in the PB-group. There were no significant changes in the placenta of all groups. This is the first report of the gene expression profiles of Phase II drug metabolizing enzymes in pregnant rat and fetal livers and placenta after treatment with typical inducers of drug metabolizing enzymes.  相似文献   
3.
We observed the manner in which alkaline phosphatase (ALPase) and osteopontin were localized in the cartilage and intramembranous bone of coccygeal vertebrae during matrix mineralization, shedding considerable light on the manner in which they develop. In the cartilage matrix of coccygeal vertebrae, we observed the localization of ALPase activity in the boundary of the proliferative and the hypertrophic zones. Granular nodules of mineralization were consistently found in the boundary of both zones, and increased in size when close to the hypertrophic zone. While osteopontin was rarely present in the early stages of mineralization, its localization along the margins of mineralized matrices in the hypertrophic zone was prominent. In contrast to cartilage, mineralized nodules in the intramembranous bone in the mid-portion of the vertebra displayed osteopontin-immunoreactivity, indicating its early synthesis and subsequent accumulation to early-stage mineralized nodules. When blood vessels, accompanied by osteoblastic and osteoclastic cell populations, invaded the cartilage, osteopontin was localized in the lower region of the hypertrophic zone, despite its maintaining the localization of ALPase and early-stage mineralization. Thus, our investigation demonstrated ALPase activity consistent with early-stage mineralization in the cartilage matrix. However, the fact that osteopontin-localization could not be pinpointed might account for its multifunctionality as concerns both the regulation of mineralization and the attachment of migrating osteogenic and osteoclastic cells to the mineralized matrix.  相似文献   
4.
Primary calcification in embryonic ossification occurs as follows: crystallization within matrix vesicles, formation of calcified nodules, and finally the establishment of expansive calcified matrix. However, the participation of the matrix vesicles in other types of bone calcification, such as bone formation during bone remodeling in adults has not been examined sufficiently. We introduce our recent observations on the presence of matrix vesicles in aged bones. In addition, although it is well known that the extracellular fluid supersaturates the calcification crystal, hydroxyapatite, the specific mechanisms by which bone matrix calcify remain unclear. In order to further approach the mechanisms of bone matrix calcification, we also review ultrastructural and localizational alterations of the matrix organics according to the progression of calcification, and an evaluation of mineral micro-environment in the calcifying sites by energy-filter transmission electron microscopy.  相似文献   
5.
Infantile hemangioma (IH) is a benign vascular tumor that gradually involutes over several years. Rapidly involuting congenital hemangioma (RICH) is the relatively rare congenital vascular tumor that is fully grown at birth and does not undergo postnatal growth and involutes during the first year. However, after involution of both IH and RICH, some have severe sequelae, such as redundant skin or conspicuous scarring, requiring additional treatment. We present the case of a 6-year-old girl with a concave deformity due to subcutaneous atrophy, skin darkening, and altered skin texture of her left zygomatic region following involution of a hemangioma. We successfully treated this patient by transferring a dermal fat graft. This technique can be beneficial for atrophic sequelae after regression of a hemangioma and is easy to perform and cosmetically effective.  相似文献   
6.
7.
The purpose of this study was to evaluate whether the existence of coronary collateral circulation influences recanalization rates of intracoronary thrombolysis. The study population consisted of 85 consecutive patients undergoing intracoronary thrombolysis within 6 hours after the onset of the first acute myocardial infarction, all of whom had a complete occlusion of the infarct-related coronary artery. Intracoronary thrombolysis with high-dose urokinase (960,000 IU) was attempted at a rate of 24,000 IU/min. Of 18 patients (group A) who had good angiographic collateral circulation to the area perfused by the infarct-related coronary artery, the obstructed artery was recanalized to a residual luminal diameter stenosis of less than or equal to 90% (successful recanalization) in only five (28%). In contrast, of 67 patients (group B) with poor or no collateral circulation, recanalization was successful in 40 (60%) (p less than 0.05). Antegrade flow of infarct-related arteries was observed following thrombolysis in 12 (67%) of 18 group A patients and in 56 (84%) of 67 group B patients (p = NS). It was concluded that (1) the presence of collaterals correlates with the presence of high-grade stenosis; (2) the presence of collaterals correlates with the presence of high-grade stenosis; (2) the presence of collaterals is inversely related to the efficacy of thrombolytic therapy; and (3) the difference in successful recanalization rates observed between the two groups probably reflects the impact of underlying stenosis severity on the effectiveness of lytic therapy.  相似文献   
8.
An unlimited supply of suitable antisera is wanted for immunoassays, analysis of antigenic determinants and precise localization of antigens in biological systems. Therefore, we produced a monoclonal antiporcine insulin antibody by the hybridoma technology and assessed it in comparison with polyclonal antibody. The spleen cells of BALB/c mice immunized against porcine insulin were hybridized with mouse myeloma cells (P3-X63-Ag8-U1). The monoclonal antibody thus generated was shown to have high binding capacity and specificity to porcine insulin in radioimmunoassay. It reacted with human insulin as well, but did not crossreact with other polypeptide hormones produced in the pancreatic islets such as glucagon, somatostatin and pancreatic polypeptide. In immunohistochemistry human and dog islets were stained by this monoclonal antibody. Rat islets were not stained, although they reacted with polyclonal anti-insulin antibody. The insulin of human serum samples measured using the monoclonal antibody was tightly correlated with that using the polyclonal antibody. These observations indicate that our hybridoma-derived monoclonal antibody is useful for immunoassay as well as localization of insulin.  相似文献   
9.
Summary The long-term efficacy of the positive inotropic and vasodilator drug, pimobendan, was assessed in 21 patients suffering from symptomatic heart failure. Patients were randomized to 16 weeks of double-blind therapy with either 2.5 or 5.0mg/day of pimobendan (n = 10), or a matching placebo (n = 11). Patients were blinded on the study drug if their clinical status had not substantially worsened during the study. Of the placebo-treated patients, 5 patients were withdrawn from the study because of a deterioration of their heart failure, while none of the active treated group was withdrawn because of increased symptoms. Quality of life, assessed by the specific activity scale derived from the metabolic costs of individual physical activity, was 3.45 ± 0.90 (SD) mets in the baseline state and increased significantly after week 16, averaging 5.07 ± 1.40 and 4.67 ± 1.47 mets at weeks 16 and 24, respectively. In the placebo-treated group, the specific activity scale was 3.27 ± 1.21 mets at the baseline and remained unchanged throughout the study period. Patients treated with pimobendan were able to significantly increase their exercise duration. The accompanying increase in peak oxygen uptake was statistically insignificant, due to the limited number of patients enrolled in the study. These results suggest that in contrast to the recent pessimistic view of the long-term efficacy of cardiotonic drugs, pimobendan is beneficial in treating patients with congestive heart failure and may favorably modify their prognosis. Further largescale evaluation of this agent is warranted.  相似文献   
10.
ObjectivesSulfated glycoconjugates (S-GCs) are essential components of dentinogenesis and osteogenesis, and are involved in the regulation of the mineralization process. The scales of Polypterus senegalus, which are homologous to teeth and phylogenetically derived from ancestral dermal skeleton, comprise true enamel, dentine, and bone. As part of the phylogenic evolutional studies on mesenchyme-derived hard tissues, we investigated the ultrastructural distribution patterns and histochemical properties of S-GCs in the dentine and bone of scales.MethodsFor detection of S-GCs, a high iron diamine–thiocarbohydrazide–silver proteinate (HID–TCH–SP) staining technique was used.ResultsS-GCs were observed in unmineralized predentine and osteoid, mineralized dentine, osteocyte pericellular matrix, but not in mineralized bone and isopedine. Most S-GCs in the dentine and osteoid were susceptible to testicular hyaluronidase, indicating that they are chondroitin sulfates.ConclusionDistinct differences in the S-GC distribution pattern between the dentine and bone were observed. The S-GC distribution pattern associated with the dentinogenesis of scales is very similar to that of mammalian mantle dentine.  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