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   677篇
  免费   31篇
耳鼻咽喉   3篇
儿科学   78篇
妇产科学   11篇
基础医学   51篇
口腔科学   28篇
临床医学   34篇
内科学   143篇
皮肤病学   7篇
神经病学   33篇
特种医学   7篇
外科学   181篇
综合类   5篇
一般理论   1篇
预防医学   86篇
眼科学   1篇
药学   15篇
肿瘤学   24篇
  2022年   5篇
  2021年   28篇
  2020年   10篇
  2019年   12篇
  2018年   22篇
  2017年   12篇
  2016年   16篇
  2015年   10篇
  2014年   18篇
  2013年   29篇
  2012年   29篇
  2011年   37篇
  2010年   22篇
  2009年   11篇
  2008年   29篇
  2007年   36篇
  2006年   47篇
  2005年   36篇
  2004年   25篇
  2003年   43篇
  2002年   34篇
  2001年   22篇
  2000年   34篇
  1999年   27篇
  1998年   8篇
  1997年   6篇
  1996年   9篇
  1995年   2篇
  1994年   3篇
  1993年   4篇
  1992年   7篇
  1991年   9篇
  1990年   8篇
  1989年   10篇
  1988年   7篇
  1987年   2篇
  1986年   9篇
  1985年   3篇
  1984年   3篇
  1979年   2篇
  1977年   2篇
  1976年   3篇
  1975年   3篇
  1974年   3篇
  1972年   2篇
  1971年   1篇
  1969年   1篇
  1968年   1篇
  1967年   1篇
  1964年   1篇
排序方式: 共有708条查询结果,搜索用时 484 毫秒
1.
AIMS: Diabetic ketoacidosis (DKA), a life-threatening acute complication of Type 1 diabetes, may be preventable with frequent monitoring of glycaemia and ketosis along with timely supplemental insulin. This prospective, two-centre study assessed sick day management using blood 3-hydroxybutyrate (3-OHB) monitoring compared with traditional urine ketone testing, aimed at averting emergency assessment and hospitalization. METHODS: One hundred and twenty-three children, adolescents and young adults, aged 3-22 years, and their families received sick day education. Participants were randomized to receive either a blood glucose monitor that also measures blood 3-OHB (blood ketone group, n = 62) or a monitor plus urine ketone strips (urine ketone group, n = 61). All were encouraged to check glucose levels > or = 3 times daily and to check ketones during acute illness or stress, when glucose levels were consistently elevated (> or = 13.9 mmol/l on two consecutive readings), or when symptoms of DKA were present. Frequency of sick days, hyperglycaemia, ketosis, and hospitalization/emergency assessment were ascertained prospectively for 6 months. RESULTS: There were 578 sick days during 21,548 days of follow-up. Participants in the blood ketone group checked ketones significantly more during sick days (276 of 304 episodes, 90.8%) than participants in the urine ketone group (168 of 274 episodes, 61.3%) (P < 0.001). The incidence of hospitalization/emergency assessment was significantly lower in the blood ketone group (38/100 patient-years) compared with the urine ketone group (75/100 patient-years) (P = 0.05). CONCLUSIONS: Blood ketone monitoring during sick days appears acceptable to and preferred by young people with Type 1 diabetes. Routine implementation of blood 3-OHB monitoring for the management of sick days and impending DKA can potentially reduce hospitalization/emergency assessment compared with urine ketone testing and offers potential cost savings.  相似文献   
2.
目的研究先天性腹裂的肠管受损害情况,探讨该病术后并发症的原因。方法利用大鼠腹裂模型,运用组织学、生化学和免疫组织化学方法,分析腹裂胎鼠肠管的组织结构,DNA和蛋白质,细胞增生和凋亡等方面的改变。结果共获得腹裂胎鼠16只,对照胎鼠21只。与对照组相比,腹裂鼠肠管变短、充血水肿、粘连,肠壁表面纤维覆盖,壁内胶原沉积,DNA总量下降,蛋白质总量基本不变,细胞增生率下降,凋亡率上升。结论腹裂的肠管损伤是多方面的,是术后肠管运动和吸收功能异常的原因,大鼠的腹裂模型是对先天性腹裂的病因、病理等方面研究的合适工具。  相似文献   
3.
INTRODUCTION: The management of children receiving small bowel grafts involves potentially life-threatening complications that affect their nutritional status. The aim of this paper was to define these factors and their influence on nutritional outcome. PATIENTS AND METHODS: Patients with intestinal failure (IF) who received an isolated small bowel transplantation (SBT) or small bowel/liver transplantation (SBLT) at our hospital during the last 6 years were reviewed for weight Z-score, biochemical nutritional parameters, total parenteral nutrition (TPN) weaning, catheter-related sepsis, rejection and steroid treatment. RESULTS: Twenty patients, 11 females and 9 males, received a SBT or a SBLT and survived the postoperative period; in the present study we only included 11 children with follow-up periods longer than 1 year. Seven males and 4 females with a mean age of 4.5 years (range, 1 to 20 years) received 6 SBLT and 5 SBT. Nine (82%) were weaned from TPN to an amino-acid or peptide enteral formula during the first 6 months after surgery. During the first year there was a significant increase in total protein from 5.11 +/- 1.8 mg/dl to 6.1 +/- 1.5 mg/dl (p < 0.05) and an increase in albumin from 3.8 +/- 0.9 mg/dl to 4.5 +/- 1.1 mg/dl (p < 0.05). There was an increase in weight Z-score in 9 patients (82%) during the first year. Mean Z-score improved from - 2.6 +/- 1 at transplant to - 1.0 +/- 0.6 (p < 0.05) after 1 year. Three patients (27.2%) had at least one rejection period, which was treated with steroids alone or in combination. Mean weight Z-score 1 year after surgery was - 0.9 +/- 0.6 for patients without rejection and - 1.24 +/- 0.8 for those with at least one rejection episode treated with steroids (p > 0.1). Four patients (36%) had at least one catheter-related sepsis episode. Mean weight Z-score 1 year after surgery was - 1.01 +/- 0.6 for patients without catheter-related sepsis and - 1.24 +/- 0.8 for those with at least one catheter-related sepsis episode (p > 0.1). CONCLUSIONS: There was a significant improvement in weight Z-score and biochemical nutritional parameters 1 year after receiving a small bowel graft. No influence of steroids or catheter-related sepsis on children's nutritional status was noted 1 year after surgery, although this point will need further evaluation.  相似文献   
4.
BACKGROUND: Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported. OBJECTIVES: To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens. METHODS: Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens. RESULTS: Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only. CONCLUSIONS: We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens.  相似文献   
5.
BackgroundObesity is a pandemic disease associated to severe health problems. Management is usually multimodal, but many patients eventually need surgery to reduce weight. Many guidelines recommend endoscopy prior to surgery. This study reviews a series of patients undergoing sleeve gastrectomy to see whether endoscopy performance and histopathological findings influence surgery outcome.Material and methodsRetrospective series of patients undergoing sleeve gastrectomy as bariatric procedure at a single institution. We have reviewed the demographic data, the associated pathologies, endoscopic findings prior to surgery, histopathological findings in the surgical resection specimen and postoperative complication rate.Results259 patients fulfilled criteria for the study. Over 70% were women and the mean age was 46.9 (SD 9.8). Preoperative endoscopy was performed in 28.9% of the patients and biopsy only in 19.3%. Helicobacter pylori was detected in 28% of the patients undergoing endoscopy (either in the biopsy or the urease test) and eradicated before surgery in all the patients. Helicobacter pylori was present in 9.7% of the surgical resection specimens and its presence was significantly associated with the development of postoperative complications, mostly staple line leaks (p = 0.01).ConclusionOur study confirms that Helicobacter infection is significantly associated with postoperative complications after sleeve gastrectomy. It is therefore important to detect its presence and eradicate it before surgery.  相似文献   
6.
7.
Thrombosis of the hepatic artery (HAT) is a severe complication of liver transplantation, and most cases need regrafting. The aim of this study was to review our experience with this complication. From January 1986 through January 1992, 76 liver transplants were performed in 59 pediatric patients at the Children's Hospital La Paz, Madrid. The diagnosis of HAT was made in 12 cases (15.7%). The common patterns of clinical presentation were: fulminant liver necrosis (5), bile leak due to necrosis of the bile duct (4), and relapsing bacteremia (3). Clinical symptoms of fulminant liver necrosis started within the first 2 weeks after transplantation, with rapid deterioration and steep rises in SGOT and SGPT levels. All these patients were retransplanted on an urgent basis, but only 1 is alive 4 years later. Four patients developed bile leaks 13 to 60 days after transplantation; SGOT, SGPT, and total bilirubin were only slightly increased. Three children were retransplanted electively and are alive with a mean follow-up of 3 years. One exceptional patient had a Roux-en-Y jejunostomy and is doing well 30 months later with his original graft. The 3 remaining children had episodes of septicemia with hepatic abscess, liver infarction, and pleural effusion. Liver function tests were normal, with bilirubin levels below 2 mg/dl. All patients were retransplanted, but only 1 is alive and well 13 months later. In the present series, we found that early HAT produces fulminant clinical deterioration requiring an urgent regraft. Late HAT presenting with either infection or bile leak allows time for treatment by elective retransplantation. The best survival was obtained in the latter group. Correspondence to: J. Vázquez  相似文献   
8.
9.
We recently reported on a new fetal rat model of esophageal atresia (EA) with tracheoesophageal fistula (TEF) induced by prenatal exposure to adriamycin (1.75 mg/kg i. p. injected daily to the pregnant dam from the 6th to 9th gestational days). With this treatment regime, many fetuses were resorbed and the number of associated malformations was very high. The present study demonstrates that similar doses of the drug administered only on the 8th and 9th gestational days allow higher fetal survival (9.7 3.9 vs. 6.8 4.7 fetuses per litter, P < 0.01) with a similar incidence of EA-TEF (41.2% vs. 56.4%, n. s.) and decreased occurence of associated anorectal and genitourinary malformations. Since this model is an instrument for further investigation of the disturbed cellular and morphogenetic events leading to EA and TEF, the narrowing of the embryologic window obtained by the present study will allow better focusing of the research on the critical period of time involved.  相似文献   
10.
Some newborns with congenital diaphragmatic hernia (CDH) and severe pulmonary hypertension cannot be saved by conventional treatment and may obtain some benefit from extracorporeal membrane oxygenation (ECMO) as a bridging measure until adequate hematosis is possible. Early prediction of the insufficiency of optimal assistance is still unclear; we reviewed our recent experience with CDH patients in an attempt to evaluate the real need for ECMO in our institution. Between 1987 and 1994, 47 newborns with CDH manifested in the first 24 h were treated with maximal ventilatory assistance (including high-frequency ventilation in 12 cases) and vasoactive drugs prior to surgical repair. In order to summarize the ventilatory and blood-gas parameters, we determined oxygenation index (OI) and ventilatory index (VI) and compared the results in survivors and nonsurvivors. Overall survival was 60% (2 cases of Fryns' syndrome were excluded from analysis). OI was 10.3±5.7 (mean ± SD) for survivors and 46.2 ± 37.8 for nonsurvivors (P < 0.01). VI was 460.9±303 and 1,532±500.6, respectively (P <0.01). Bayesian analysis and receiver operating characteristic curves enabled us to select a threshold value of OI of 20 as the best means of predicting survival in our current conditions (sensitivity: 0.7, specificity: 0.83). The generally accepted figure of 40 had a sensitivity of 1 but a specificity of only 0.44. For VI, the best threshold value was 1,100 (sensitivity: 0.93, specificity: 0.94), whereas the generally used figure of 1,000 had 0.89 and 1, respectively. According to our results, with our current management conditions, approximately 50% of our CDH patients might have obtained some benefit from ECMO.  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