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   64篇
  免费   8篇
儿科学   2篇
妇产科学   10篇
基础医学   15篇
临床医学   6篇
内科学   7篇
皮肤病学   1篇
神经病学   3篇
特种医学   4篇
外科学   15篇
综合类   1篇
药学   2篇
肿瘤学   6篇
  2021年   1篇
  2019年   1篇
  2018年   4篇
  2017年   3篇
  2016年   1篇
  2014年   2篇
  2013年   5篇
  2012年   7篇
  2011年   1篇
  2010年   2篇
  2009年   5篇
  2007年   2篇
  2006年   2篇
  2004年   3篇
  2003年   1篇
  2000年   3篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1995年   2篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1989年   1篇
  1987年   3篇
  1986年   2篇
  1985年   2篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1977年   2篇
  1976年   2篇
  1975年   1篇
  1961年   1篇
排序方式: 共有72条查询结果,搜索用时 256 毫秒
1.
Deletions of phage λ extending from att into and beyond the cI gene have been isolated as Spi? plaque-forming mutants of the N-independent nin-5 mutant. Twenty-eight deletions end within the cI gene, one between cI and prm, one between prm and OR, and two between OR and the O gene. The last three mutants are virulent. The two mutants with deletions removing both of the major promotors, PL and PR, presumably are controlled by the block of host genes carried by these transducing phages.  相似文献   
2.

Introduction

Difficulties have been reported in the patient distribution during Mass Casualty Incidents. In this study we analysed the regional patient distribution protocol (PDP) and the actual patient distribution after the 2009 Turkish Airlines crash near Amsterdam.

Methods

Analysis of the patient distribution of 126 surviving casualties of the crash by collecting data on medical treatment capacity, number of patients received per hospital, triage classification, Injury Severity Score (ISS), secondary transfers, distance from the crash site, and the critical mortality rate.

Results

The PDP holds ambiguous definitions of medical treatment capacity and was not followed. There were 14 receiving hospitals (distance from crash: 5.8–53.5 km); four hospitals received 133–213% of their treatment capacity, and 5 hospitals received 1 patient. Three hospitals within 20 km of the crash did not receive any casualties. Level I trauma centres received 89% of the ‘critical’ casualties and 92% of the casualties with ISS ≥ 16. Only 3 casualties were secondarily transferred, and no casualties died in, or on the way to hospital (critical mortality rate = 0%).

Conclusion

Patient distribution worked out well after the crash as secondary transfers were low and critical mortality rate was zero. However, the regional PDP was not followed in this MCI and casualties were unevenly distributed among hospitals. The PDP is indistinctive, and should be updated in cooperation between Emergency Services, surrounding hospitals, and Schiphol International Airport as a high risk area.  相似文献   
3.
4.

Introduction

The incidence and nature of penetrating injuries differ between countries. The aim of this study was to analyze characteristics and clinical outcomes of patients with penetrating injuries treated at urban Level-1 trauma centers in the USA (USTC) and the Netherlands (NLTC).

Methods

In this retrospective cohort study, 1331 adult patients (470 from five NLTC and 861 from three USTC) with truncal penetrating injuries admitted between July 2011 and December 2014 were included. In-hospital mortality was the primary outcome. Outcome comparisons were adjusted for differences in population characteristics in multivariable analyses.

Results

In USTC, gunshot wound injuries (36.1 vs. 17.4%, p?<?0.001) and assaults were more frequent (91.2 vs. 77.7%, p?<?0.001). ISS was higher in USTC, but the Revised Trauma Score (RTS) was comparable. In-hospital mortality was similar (5.0 vs. 3.6% in NLTC, p?=?0.25). The adjusted odds ratio for mortality in USTC compared to NLTC was 0.95 (95% confidence interval 0.35–2.54). Hospital stay length of stay was shorter in USTC (difference 0.17 days, 95% CI ?0.29 to ?0.05, p?=?0.005), ICU admission rate was comparable (OR 0.96, 95% CI 0.71–1.31, p?=?0.80), and ICU length of stay was longer in USTC (difference of 0.39 days, 95% CI 0.18–0.60, p?<?0.0001). More USTC patients were discharged to home (86.9 vs. 80.6%, p?<?0.001). Readmission rates were similar (5.6 vs. 3.8%, p?=?0.17).

Conclusion

Despite the higher incidence of penetrating trauma, particularly firearm-related injuries, and higher hospital volumes in the USTC compared to the NLTC, the in-hospital mortality was similar. In this study, outcome of care was not significantly influenced by differences in incidence of firearm-related injuries.
  相似文献   
5.
The purpose of this planning study was to determine whether intensity-modulated radiation therapy (IMRT) reduces the radiation dose to organs at risk (OAR) when compared with 3D conventional radiation therapy (3D-CRT) in patients with vulvar cancer treated by irradiation. This study also investigated the use of sequential IMRT boost (seq-IMRT) and simultaneous integrated boost (SIB-IMRT) for dose escalation in the treatment of locally advanced vulvar cancer. Five vulvar cancer patients treated in the postoperative setting and 5 patients treated with definitive intent (def-group) were evaluated. For the postoperative group, 3D-CRT and IMRT plans to a total dose (TD) of 45 Gy were generated. For the def-group, 4 plans were generated: a 3D-CRT and an IMRT plan to a TD of 56.4 Gy, a SIB-IMRT plan to a TD of 56 Gy, and a SIB-IMRT with dose escalation (SIB-IMRT-esc): TD of 67.2 Gy. Mean dose and dose-volume histograms were compared using Student's t-test. IMRT significantly (all p < 0.05) reduced the Dmean, V30, and V40 for all OAR in the adjuvant setting. The V45 was also significantly reduced for all OAR except the bladder. For patients treated in the def-group, all IMRT techniques significantly reduced the Dmean, V40, and V45 for all OAR. The mean femur doses with SIB-IMRT and SIB-IMRT-esc were 47% and 49% lower compared with 3D-CRT. SIB-IMRT-esc reduced the doses to the OAR compared with seq-3D-CRT but increased the Dmax. for the small bowel, rectum, and bladder. IMRT reduces the dose to the OAR compared with 3D-CRT in patients with vulvar cancer receiving irradiation to a volume covering the vulvar region and nodal areas without compromising the dosimetric coverage of the target volume. IMRT for vulvar cancer is feasible and an attractive option for dose escalation studies.  相似文献   
6.
Ankle injuries are a huge medical and socioeconomic problem. Many people have a traumatic injury of the ankle, most of which are a result of sports. Total costs of treatment and work absenteeism due to ankle injuries are high. The prevention of recurrences can result in large savings on medical costs. A multidisciplinary clinical practice guideline was developed with the aim to prevent further health impairment of patients with acute lateral ankle ligament injuries by giving recommendations with respect to improved diagnostic and therapeutic opportunities. The recommendations are based on evidence from published scientific research, which was extensively discussed by the guideline committee. This clinical guideline is helpful for healthcare providers who are involved in the management of patients with ankle injuries.  相似文献   
7.
Administrations of the glucocorticoid receptor antagonist (anti-glucocorticoid, RU38486) and the mineralocorticoid antagonist (anti-mineralocorticoid, RU28318) followed by frequent, sequential blood sampling were employed to investigate the possible role the brain mineralocorticoid receptor (MR, type I) and glucocorticoid receptor (GR, type II) have in the regulation of basal and stress-induced adrenocortical secretion in the rat. The anti-mineralocorticoid and anti-glucocorticoid were administered subcutaneously (s.c.) at doses of 2.5 mg and 1.0 mg/100 g body weight, respectively. Both antagonists were also given intracerebroventricularly (i.c.v.) at a dose of 100 ng/rat. Under basal non-stressed conditions (at the diurnal trough in the morning), injections of either saline, anti-glucocorticoid (s.c. or i.c.v.) or anti-mineralocorticoid (s.c.) did not have effect on the plasma corticosterone level. The anti-mineralocorticoid given intracerebroventricularly, however, caused an elevation of plasma corticosterone up to 60 min after the injection. Exposure of the rats to a novel environment resulted in a large increase in the plasma corticosterone level, which was slightly reduced in the rats treated with the anti-glucocorticoid. In vehicle-treated rats, the level returned to basal values at 90 min, while in the anti-glucocorticoid- and anti-mineralocorticoid-treated groups, it remained elevated for prolonged periods. The present study thus shows that (1) the anti-glucocorticoid RU38486 via the brain GR has no effect on the basal plasma corticosterone level in the morning but interferes with a glucocorticoid negative feedback following stress and (2) the anti-mineralocorticoid RU28318 via the brain MR elevates the basal plasma corticosterone level and enhances adrenocortical secretion following stress.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
The affinity constants (Ka) of monoclonal antibodies (MAb) for binding to their corresponding antigens (Ag), unlabelled and in buffered solution were determined by the following procedure: 1. Incubation of MAb (fixed concentration) with Ag (concentration dilution series). 2. Rapid bound/free separation by adding immobilized second antibody, followed by centrifugation. 3. Determination of free Ag in the supernatant using a gold sol particle agglutination immunoassay (SPIA) in a microtitration plate format. 4. Calculations and interpretation were based on Scatchard and Sips plots. Ka values found by this procedure were found to be similar to those obtained by a radio-immunoassay (RIA) procedure. The present method avoids possible artefacts in Ka values introduced by the procedure or chemical modification due to labelling of MAb or Ag. It enables rapid, simultaneous screening of a considerable number of different MAbs under non-specialized (i.e. RIA) laboratory conditions.  相似文献   
9.
Moloney cell surface antigen (MCSA) is serologically detectable on Moloney murine leukemia virus (Mo-MuLV)-induced lymphomas. It is probably related to the tumor-associated transplantation antigen of these lymphomas. We characterized MCSA by using the typing antiserum in radioimmunoprecipitations followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Surface-iodinated Mo-MuLV-infected cells were used to identify the molecular nature of MCSA. It appeared that MCSA was expressed as an entity of 82,000 apparent molecular weight (p82MCSA). Translation of size-fractionated mRNAs from infected cells in oocytes of Xenopus laevis showed that p82MCSA was made on an mRNA of the same size (22 S) as that coding for the Mo-MuLV env proteins. Moreover, p82MCSA was processed in oocytes to proteins exactly comigrating in the gel with gp70, p15E, and p12E. Competition experiments with unlabeled virus showed that MCSA and the MCSA-related env-like proteins made in oocytes were not related to any of the Mo-MuLV structural proteins. We concluded that MCSA has the properties of the product of the env gene of a murine C-type virus different from Mo-MuLV.  相似文献   
10.
Autologous bone grafting is currently considered the treatment of choice for correction of large bone defects. However, to avoid morbidity associated with autologous bone harvesting many artificial bone-substitute materials have been developed over the years. A new generation of resorbable materials is emerging, with promising results so far. In order to investigate the possibility to use one of these new materials as an alternative with better results than hydroxyapatite, an experimental study was performed. A new resorbable calcium phosphate particles and paste forms, the latter of which hardens in situ after application. In 28 sheep, a 3-cm segmental tibial defect was made and intramedullary fixed by an interlocking nail. Twelve weeks after defect filling, radiological, biomechanical, and histological examinations were performed. Mean radiographic and biomechanical tests results were compared with the Mann-Whitney test. Significance was set at p<0.05. Radiographically, the resorbable paste group performed better than all other groups. Biomechanical investigations showed a higher torsional stiffness (p=0.049) for the resorbable calcium-phosphate paste group in comparison with autologous bone. On histological examination, no adverse effects were observed in the calcium-phosphate groups. Resorption by osteoclasts was seen in the resorbable implants. In conclusion, the current study shows an advantageous radiological and mechanical outcome for resorbable calcium phosphates. This indicates that these new materials might be a potential alternative for autologous bone grafting in humans.  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