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   259篇
  免费   15篇
  国内免费   7篇
耳鼻咽喉   1篇
儿科学   28篇
妇产科学   7篇
基础医学   26篇
口腔科学   15篇
临床医学   38篇
内科学   30篇
皮肤病学   7篇
神经病学   13篇
特种医学   38篇
外科学   35篇
综合类   9篇
预防医学   9篇
药学   14篇
肿瘤学   11篇
  2023年   1篇
  2022年   4篇
  2021年   2篇
  2020年   5篇
  2019年   2篇
  2018年   7篇
  2017年   3篇
  2016年   3篇
  2015年   8篇
  2014年   8篇
  2013年   6篇
  2012年   8篇
  2011年   7篇
  2010年   17篇
  2009年   15篇
  2008年   3篇
  2007年   17篇
  2006年   25篇
  2005年   1篇
  2004年   4篇
  2003年   1篇
  2002年   8篇
  2001年   4篇
  2000年   2篇
  1999年   4篇
  1998年   16篇
  1997年   16篇
  1996年   12篇
  1995年   7篇
  1994年   14篇
  1993年   10篇
  1992年   6篇
  1991年   1篇
  1989年   1篇
  1988年   5篇
  1987年   2篇
  1986年   4篇
  1985年   7篇
  1984年   3篇
  1982年   3篇
  1981年   4篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1975年   1篇
排序方式: 共有281条查询结果,搜索用时 46 毫秒
101.
正The prophylactic effects of Chinese propolis against cypermethrin toxicity were evaluated by performing ovary and uterus histopathology,as well as by characterizing ovarian function,embryos,and litters.Cypermethrin induced atypia in the ovary and uterus,and decreased the ovulation sites and the number of embryos.Cypermethrin-induced oxidative stress during pregnancy,decreased the parturition rate as well as the number and weight  相似文献   
102.
Aim of study : To measure the effect of specific preoperative information on postoperative anxiety, satisfaction with information, and demand for analgesia, of Chinese males having transurethral resection of the prostate (TURP). Design : A controlled experimental design. The researchers allocated all patients ( n =30) undergoing TURP in a general hospital in Hong Kong, during a 3-month period, to one of two groups. The experimental group ( n =15) received a specific information pamphlet and a general preoperative counselling video. The control group ( n =15) received a video alone. Procedure and measures : Following ethical approval, a researcher took baseline measures of state and trait anxiety using the Chinese State-Trait Anxiety Inventory (C -STAI). Five days after surgery the researcher administered the C-STAI (A-State), a patients' satisfaction questionnaire, and, recorded requests for analgesia during the first 5 postoperative days. Results : Experimental subjects reported significantly lower anxiety levels post-operatively and a significantly higher level of satisfaction with the preoperative information, than controls. Postoperative demand for analgesia did not significantly differ between groups. Conclusions : The findings support the importance of providing patients with specific, written preoperative information about their surgery and its effects to minimize their postoperative anxiety levels, and improve their satisfaction with the care provided.  相似文献   
103.
目的:制备一种廉价、安全而且来源丰富的生物敷料,以用于烧伤患者微粒皮移植后和削痂后创面的保护。方法:实验于2003-10/2007-03在积水潭医院烧伤研究所完成。①主要材料:健康山羊5只,纯种新西兰大白兔10只;戊二醛猪皮(清华源兴生物制品公司);冷冻保存的人皮(志愿者捐献)。②实验方法:山羊麻醉处死,去毛后取全层皮肤,通过反复冻融、配合超声震荡和洗脱液处理,在保证胶原支架完整情况下去除导致皮肤排斥反应的细胞成分,获得脱细胞羊皮基质,冷冻保存。③实验评估:利用常规病理检查和电子显微镜检查其有无明显细胞碎片残留;细菌真菌培养,测试其机械强度、亲水性和细胞毒性,通过动物埋藏实验确定其组织相容性,并与戊二醛交联的脱细胞猪皮以及冷冻保存的人皮作对照。结果:制备的脱细胞羊皮基质,常规病理检查、免疫组织化学染色、电子显微镜检查均未发现表皮和真皮细胞残留;细菌真菌培养呈阴性;为亲液固体,质感柔软有弹性,含水量、极限抗拉强度、应力-应变量、应力松弛特征、蠕变性等物理性能均与冷冻人皮相似,明显优于戊二醛猪皮;细胞毒性0级,在国家标准允许范围内;植入兔背部脊柱两侧的肌肉组织内后,能够与组织很好的融合,并诱导细胞和血管长入,组织相容性良好。结论:采用冻融法制备的脱细胞羊皮敷料安全、廉价、来源丰富,达到临床手术应用的保护性生物敷料标准。  相似文献   
104.
The purpose of the study reported here was the determination of the efficacy of a postoperative autologous blood drainage and transfusion device in reducing allogeneic red cell requirements in patients undergoing elective knee arthroplasty. The study was a randomized controlled trial with adult patients undergoing unilateral elective arthroplastic knee surgery. Patients underwent suction drainage, attached to an autologous blood drainage and transfusion device, or standard suction drainage. Allogeneic red cells were given according to strict transfusion guidelines based on blood loss and postoperative hemoglobin values. Outcome measures included the mean number of allogeneic red cell concentrates required and the number of patients in each group who required no transfusion. Patients assigned to standard suction drainage had a mean allogeneic red cell utilization of 1.2 units (SD 1.0), as compared to a mean of 0.4 units (SD 0.8) in the group undergoing drainage with the autologous blood drainage and transfusion device (p = 0.0007). The percentage of patients not requiring allogeneic red cells was significantly higher in the latter group (74.3% vs. 32.5%; p = 0.002). The postoperative drainage and transfusion device was efficacious in reducing the amount of allogeneic red cells required by patients undergoing knee arthroplasty, and its use resulted in a 42 percent reduction in the number of patients requiring allogeneic transfusion.  相似文献   
105.

Background

Preterm labour is the main cause of perinatal morbidity and mortality in the Western world. At present, there is evidence that tocolysis for 48 hours is useful in women with threatened preterm labour at least before 32 weeks. This allows transfer of the patient to a perinatal centre, and maximizes the effect of corticosteroids for improved neonatal survival. It is questionable whether treatment with tocolytics should be maintained after 48 hours.

Methods/Design

The APOSTEL II trial is a multicentre placebo-controlled study. Pregnant women admitted for threatened preterm labour who have been treated with 48 hours corticosteroids and tocolysis will be eligible to participate in the trial between 26+0 and 32+2 weeks gestational age. They will be randomly allocated to nifedipine (intervention) or placebo (control) for twelve days or until delivery, whatever comes first. Primary outcome is a composite of perinatal death, and severe neonatal morbidity up to evaluation at 6 months after birth. Secondary outcomes are gestational age at delivery, number of days in neonatal intensive care and total days of the first 6 months out of hospital. In addition a cost-effectiveness analysis will be performed. Analysis will be by intention to treat. The power calculation is based on an expected 11% difference in adverse neonatal outcome. This implies that 406 women have to be randomised (two sided test, β 0.2 at alpha 0.05).

Discussion

This trial will provide evidence as to whether maintenance tocolysis reduces severe perinatal morbidity and mortality in women with threatened preterm labour before 32 weeks.

Trial Registration

Clinical trial registration: http://www.trialregister.nl, NTR 1336, date of registration: June 3rd 2008.  相似文献   
106.
The aim of the present study was to differentiate between prostate adenocarcinoma and urothelial carcinoma among Egyptian patients by immunohistochemical methods. Two groups of patients were used: urothelial group, consisted of 9 cystitis, 21 transitional cell carcinoma (TCC) and 5 urinary bladder mucoid adenocarcinoma (MAC) and prostatic group, consisted of 9 nodular prostatic hyperplasia (NPH) and 21 prostatic adenocarcinoma (PAC). H–E stained sections were performed to confirm the diagnosis and evaluate the histopathological characteristics of the tumor. Immunohistochemical techniques were used for detection of P63, CK7, CK10 and PSA. The results showed that in urothelial group, positive p63and CK7 immunostaining was observed in all cases of cystitis, transitional cell carcinoma and urinary bladder mucoid adenocarcinoma. All cases of cystitis, transitional cell carcinoma and urinary bladder mucoid adenocarcinoma were CK10 and PSA negative. In prostate group, positive p63 immunostaining was observed in all cases of NPH and in prostatic adenocarcinoma. Positive CK7 immunostaining was observed in all cases of NPH while all cases of prostatic adenocarcinoma were CK7 negative. Positive CK10 immunostaining was observed in all cases of NPH. In prostatic adenocarcinoma, 11 cases were CK10 positive and 10 cases were CK10 negative. All cases of NPH and prostatic adenocarcinoma were PSA positive. In conclusion, the result of the present work proved that p63 and CK7 can be used along with other markers to differentiate between adenocarcinoma of prostate and urothelial carcinoma of the bladder. Also, CK10 and PSA are useful for distinguishing prostate cancer from urothelial carcinoma.  相似文献   
107.
We consecutively recruited 75 patients with intractable headache syndromes, divided them into three groups (frequent migraine = FM, transformed migraine = TM, and tension type headache = TT) based on their headache symptoms and treated all 75 with divalproex sodium. Thirty-six patients (48%) reported a ³ 50% reduction in headache frequency. We noted significantly different treatment response rates in the three patient groups, with FM patients reporting the highest rate of improvement (11/18 = 61%), TM patients an intermediate rate (22/43 = 51%), and TT patients the lowest response rate (3/14 = 21%), These data suggest that prophylactic therapy with divalproex may be effective in selected patients with intractable headache syndromes and that identification of clinically distinct headache subtypes may assist in predicting response to treatment.  相似文献   
108.
It is generally assumed that febrile nonhemolytic transfusion reactions are an immunologically mediated reaction involving the recipient's plasma and the white cells in the donor unit. This has led to the use of white cell reduction and pretransfusion medication, to try to minimize these reactions. To better understand febrile transfusion reactions, a prospective study was performed in which all patients receiving platelet and red cell transfusions in a tertiary-care medical center were interviewed before and after transfusion to obtain information about the typical presentation of the syndrome. It was found that transfusion reactions were much more frequently associated with platelet transfusion (30.8%) than with red cell transfusion (6.8%, p < 0.0005). The routine use of antipyretics prevented most episodes of fever but did not prevent the occurrence of other symptoms such as chills, cold, and discomfort. The application of logistic regression analysis revealed that the dominant factor determining the risk of a reaction was not white cell contamination, but the age of the component (p < 0.005). The significant relationship between reaction and the increasing age of the component suggests that cytokines released in the component during storage may be responsible for many reactions to blood components.  相似文献   
109.
To evaluate the effectiveness of oral sucrose in the prevention of pain-induced crying in preterm infants, a sample of 28 healthy neonates (15M, 13F; gestational age at procedure less than 37 weeks) who were having routine blood drawn by arm venipuncture was studied. Infants were randomly allocated to receive by mouth, using a syringe, 2 ml of one of three solutions: spring water (group W) and sucrose 12 and 24% w/v (groups S12 and S24, respectively), all in water vehicle. After 2 min, while awake, arm venipuncture was performed and duration of crying was measured. The time spent crying was reduced in the group treated with the sweetest solution (S24, n = 8, mean =19.1 s). No difference was observed between the S12 group ( n = 8, mean = 63.1 s) and W group ( n = 12, mean = 72.9 s). Physiological measurements were recorded at different time points to evaluate excessive basal and procedural distress.  相似文献   
110.
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