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   264篇
  免费   6篇
儿科学   6篇
妇产科学   7篇
基础医学   24篇
口腔科学   10篇
临床医学   20篇
内科学   60篇
神经病学   12篇
特种医学   1篇
外科学   48篇
预防医学   7篇
药学   23篇
肿瘤学   52篇
  2023年   2篇
  2022年   3篇
  2021年   6篇
  2020年   2篇
  2019年   5篇
  2018年   3篇
  2016年   3篇
  2015年   10篇
  2014年   8篇
  2013年   12篇
  2012年   17篇
  2011年   15篇
  2010年   5篇
  2009年   10篇
  2008年   5篇
  2007年   6篇
  2006年   8篇
  2005年   13篇
  2004年   10篇
  2003年   10篇
  2002年   8篇
  2001年   7篇
  2000年   15篇
  1999年   6篇
  1998年   4篇
  1996年   3篇
  1994年   1篇
  1993年   7篇
  1992年   5篇
  1991年   11篇
  1990年   10篇
  1989年   8篇
  1988年   8篇
  1987年   4篇
  1986年   4篇
  1985年   4篇
  1984年   1篇
  1983年   3篇
  1978年   2篇
  1977年   2篇
  1974年   1篇
  1973年   1篇
  1969年   1篇
  1968年   1篇
排序方式: 共有270条查询结果,搜索用时 31 毫秒
1.
The correlation between the extent of peritumoral edema and the proliferative potential or the infiltration of mononuclear cells was studied in 17 gliomas. The peritumoral edema was evaluated on contrast enhanced CT scan as the ratio of the low density area around the tumor to the enhanced high density area. The proliferative potential and the infiltration of mononuclear cells into the tumor were investigated immunohistochemically using monoclonal antibody (MAb) against DNA polymerase alpha and anti-Leu MAb's respectively. There was a significant correlation between the extent of the peritumoral edema and the percentage of DNA polymerase alpha positive cells. The degree of the infiltration of mononuclear cells into the tumor tissue also correlated with the extent of peritumoral edema. In gliomas with high proliferative potential and/or severe infiltration of mononuclear cells, the peritumoral edema may be aggravated by disruption of the blood-brain-barrier and increased vascular permeability.  相似文献   
2.
3.
Radical operation for patients with thoracic esophageal cancer is one of the surgical procedures with the most severe surgical stress in the digestive system because of frequent serious postoperative complications particularly with respiratory problems. For the purpose of reducing surgical influences and postoperative pulmonary complications in patients with esophageal cancer, we have been insisting on "one-stage operation" with preceding reconstruction of the esophagus on the basis of our clinical experiences and model experiments. In the model experiments minimizing radical operation for thoracic esophageal cancer, the increase of intra-operative and post-operative pulmonary water content in the laparotomy-preceding group (LPG) is lesser than in the thoracotomy-preceding group (TPG). This results were also supported by histological findings. In the TPG, a tendency of pulmonary water accumulation was accelerated with an increase of surgical influences and, in addition, pulmonary water accumulation was noted even in the lung of the opposite side. Furthermore, the host defense reaction to the surgery and the influences of respiratory and circulatory systems were observed predominantly in this group. It is concluded that one-stage operation with preceding reconstruction of the esophagus shows a rationality in reducing the surgical influences to the body, especially to the pulmonary systems.  相似文献   
4.
The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase alpha. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase alpha, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase alpha-positive cells (the "polymerase alpha score") ranged from 72.0% to 77.1%, the Ki-67-positive cells (the "Ki-67 score") ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%. For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase alpha scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase alpha scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase alpha scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors. These findings suggest that immunostaining of DNA polymerase alpha is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase alpha scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores.  相似文献   
5.
An extremely low birth weight (832 g) and 29 gestational week neonate underwent surgical ligation of patent ductus arterious 20 days after birth and repair of coarctation of the aorta two months after the first operation. She developed asphyxia neonatorum and was artificially ventilated because of IRDS and attack of apnea. At the first operation, anesthesia was maintained with fentanyl and sevoflurane. The only perioperative complication was severe hypothermia (34.5 degrees C). At the second operation, anesthesia maintenance was identical to the first operation. The only perioperative complication was mild hyperthermia (37.7 degrees C). The key points of anesthetic management were the use of a low inspired oxygen fraction to avoid retrolental fibroplasia at a gestational age before 32 weeks and management of the baby's temperature.  相似文献   
6.
Abstract: In the present study, we investigated the role of the spleen in experimental hepatic ischemia/reperfusion in the rat. After a 90-min period of ischemia in the left and middle hepatic lobes, the ischemia was released and the liver was reperfused for up to 24 h. Plasma alanine aminotransferase reached a peak 3 h after the onset of reperfusion, and gradually decreased thereafter. A histological examination revealed evidence of hepatocellular necrosis and degeneration, especially 24 h after the onset of reperfusion. In addition, there was a noticeable accumulation of polymorphonuclear cells in the liver following ischemia/reperfusion. A splenectomy performed just prior to ischemia/reperfusion reduced both biochemical and histological hepatocellular injury. The number of polymorphonuclear cells in the liver following ischemia/reperfusion was significantly reduced in rats subjected to splenectomy, suggesting that the increase in polymorphonuclear cells may contribute to liver injury. The number of mononuclear cells also increased in the marginal zones of the spleen following ischemia/reperfusion, and appeared to be derived from the splenic monocyte/macrophage population, based on immunohistochemical studies. The spleen plays an important role in the pathogenesis of hepatic ischemia/reperfusion injury and the splenic monocyte/macrophage population contributes to liver damage.  相似文献   
7.
8.

Background

Organizational justice has recently been introduced as a new concept as psychosocial determinants of employee health, and an increase in precarious employment is a challenging issue in occupational health. However, no study investigated the association of organizational justice with mental health among employees while taking into account employment contract.

Purpose

The purpose of the present study was to investigate the prospective association of organizational justice (procedural justice and interactional justice) with psychological distress by employment contract among Japanese employees.

Methods

A total of 373 males and 644 females from five branches of a manufacturing company in Japan were surveyed. At baseline (August 2009), self-administered questionnaires, including the Organizational Justice Questionnaire (OJQ), the K6 scale (psychological distress scale), the Eysenck Personality Questionnaire-Revised (EPQ-R), and other covariates, were used. After one-year follow-up (August 2010), the K6 scale was used again to assess psychological distress. Multiple logistic regression analyses were conducted by sex and employment contract.

Results

After adjusting for demographic characteristics, psychological distress, and neuroticism at baseline, low procedural justice was significantly associated with a higher risk of psychological distress at follow-up among non-permanent female employees, while no significant association of procedural justice or interactional justice with psychological distress at follow-up was observed among permanent male or female employees. The results of non-permanent male employees could not be calculated because of small sample size.

Conclusions

Low procedural justice may be an important predictor of psychological distress among non-permanent female employees.  相似文献   
9.
The measurement of corrected count increment at 1-h post-transfusion (CCI-1 h) of platelet concentrate (PC) transfusion is recommended, but in the revised Japanese Guideline (2017) it was changed to “after 10-min to 1-h”, following the revision of the guidelines from Western countries. Here, we aimed to investigate on the feasibility to apply the CCI measured at 10-min or 30-min post-transfusion as the surrogate of CCI-1 h. Peripheral blood was collected at 10-min, 30-min and 1-h post-transfusion of PC and the effectiveness of the transfusion was analyzed based on the CCI. In the period from December 2017 to February 2020, 8 patients, who received multiple PC transfusion (total 208) at our institution, were analyzed. We performed the univariate analyses to examine the relationship between CCI value and the categorical variables, p-value <0.1 was obtained for gender (p = 2.91 × 10?19), fever after transfusion (p = 0.0163). The qualitative variables, namely measurement time (p = 0.0553), also showed p-value <0.1. Using these factors as covariates in the mixed effect model, we found that the measurement time (p = 0.0007) had a significant effect on the CCI value when looking at fixed effects. Although there is a tendency for decreased CCI values with time progression, the slope of the change in the mixed model was -0.00307, indicating that the CCI difference among the 3 measurements was small. Here we provide evidence that CCI measured at 10-min and 30-min post-transfusion give results comparable to those measured at 1-h post-transfusion, under the Japanese practice of platelet transfusion, which relies on 100 % single-donor apheresis PC, and ABO-identical whenever possible.  相似文献   
10.
It is well known that host immunity plays an important role in the defense against colorectal cancer (CRC) progression. The effects of autoimmune diseases, such as rheumatic disease (RD) in which the immune system is deregulated, on this immunity have not been fully investigated. The medical records of 1299 consecutive patients diagnosed with primary colorectal cancer who underwent surgical resection were retrospectively reviewed. The clinicopathologic factors of 28 subjects with RD (RD group) were compared with those of 1271 patients without RD (non-RD group). Compared to the non-RD group, the RD group was typified by a predominance of females (P < 0.01), older age (P < 0.01), and a lower incidence of rectal cancer (P = 0.02). Although no difference was observed between the groups in terms of TNM classification, disease-free and overall survival were significantly poorer in the RD group in both univariate and multivariate analyses. Subjects who had RD for more than 10 years tended to have a higher frequency of lymph node metastasis (P = 0.06) and a significantly higher incidence of synchronous distant metastasis (P = 0.035) at the time of cancer diagnosis. RD was associated with a significantly poorer prognosis of colorectal cancer, suggesting that deregulation of the immune system by autoimmune diseases may adversely affect the host immune defense against colorectal cancer progression.Key words: Colorectal cancer, Rheumatic disease, Host immunity, PrognosisIt is well known that host immunity plays an important role in defenses against the development and progression of cancer. The degree of lymphocyte infiltration into tumors has been reported to correlate with improvements of patient survival.1 In carcinogen-induced mouse models of cancer, primary tumor susceptibility has been found to be enhanced in immunocompromised mice; conversely, the capacity for such tumors to grow after transplantation into wild-type mice is reduced.2,3 Although cancer cells originate from autologous normal tissue, the immune system can recognize even minimal cellular alterations, distinguish cancerous from normal cells, and elicit an immune response.In autoimmune diseases represented by rheumatic disease (RD), the immune system loses the ability to distinguish nonself from self, eliciting an immune response against self-antigens; in this process, there is a possibility that immune defenses against non-normal cells are lost or impaired, facilitating the development and progression of cancer. In addition, the development of RD associated with cancer has been reported, and as its development is dependent on the production of substances such as hormones, peptides, autocrine and paracrine mediators, and antibodies or the stimulation of cytotoxic lymphocytes, the condition is known as paraneoplastic rheumatic syndrome. In such cases, RD tends to be less responsive to therapy than its nonparaneoplastic equivalents, and instead, treatment of the underlying cancer usually results in regression of RD.4,5 Thus, it is postulated that RD and cancer are closely associated. However, only a few reports on the incidence and risk of cancer among patients with RD exist,6,7 and the characteristics and prognosis of colorectal cancer (CRC) in these patients remain to be elucidated.In the present study, we investigated the development of CRC in the background of an immunologic disorder caused by RD, with the hypothesis that patients with CRC and autoimmune diseases such as RD will have a poorer prognosis than those without RD, as a result of depressed antitumor immunity caused by immune system incompetence. Thus, we aimed to clarify the features and prognosis of CRC-associated RD, and for this purpose, we compared the clinicopathologic features of patients with CRC with or without underlying RD.  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