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   1037篇
  免费   83篇
  国内免费   4篇
耳鼻咽喉   11篇
儿科学   13篇
妇产科学   15篇
基础医学   162篇
口腔科学   6篇
临床医学   136篇
内科学   234篇
皮肤病学   10篇
神经病学   120篇
特种医学   18篇
外科学   130篇
综合类   3篇
一般理论   1篇
预防医学   61篇
眼科学   15篇
药学   91篇
中国医学   5篇
肿瘤学   93篇
  2024年   2篇
  2023年   16篇
  2022年   51篇
  2021年   62篇
  2020年   36篇
  2019年   37篇
  2018年   32篇
  2017年   39篇
  2016年   43篇
  2015年   43篇
  2014年   41篇
  2013年   57篇
  2012年   64篇
  2011年   80篇
  2010年   40篇
  2009年   34篇
  2008年   95篇
  2007年   60篇
  2006年   61篇
  2005年   46篇
  2004年   49篇
  2003年   39篇
  2002年   30篇
  2001年   2篇
  1999年   3篇
  1998年   9篇
  1997年   5篇
  1996年   3篇
  1995年   4篇
  1994年   3篇
  1993年   2篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   2篇
  1984年   3篇
  1983年   4篇
  1981年   1篇
  1980年   3篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1972年   2篇
  1968年   1篇
  1967年   1篇
  1966年   3篇
排序方式: 共有1124条查询结果,搜索用时 31 毫秒
1.
2.
Mid- to long-term outcome of disc excision in adolescent disc herniation.   总被引:3,自引:0,他引:3  
BACKGROUND CONTEXT: Adolescent disc herniation and its surgical treatment have been the subjects of many published clinical series. The majority of these series were heterogeneous; the number of adolescent patients (12-17 years) as opposed to young adults (18-20 years) was generally small and the length of follow-up varied greatly. Although the short-term outcome of disc excision in adolescents was mostly favorable, their long-term outcome is unknown. OBJECTIVES: To evaluate the mid- and long-term results of discectomy in patients younger than 17 years of age. STUDY DESIGN: Retrospective examination of a series of adolescent patients under the age of 17 years who underwent surgery for lumbar intervertebral disc herniation. PATIENT SAMPLE: The medical records of 26 patients (15 males, 11 females, 12-17 years old [average 14.6]) who were operated for lumbar intervertebral disc herniation in three spine centers between 1984 and 2002 were reviewed. These subjects represented the total number of patients meeting the criteria of adolescents undergoing discectomy for lumbar disc herniation in these institutions during the study period. All patients were located and contacted by an independent observer not involved in the care of these patients. Low back pain associated with leg pain was the main clinical symptom in 20 patients (77%), leg pain in 4 (15%), and back pain in 2 (8%). They all underwent posterior disc excision: 23 (88%) patients had one level discectomy, and 3 (12%) had simultaneous discectomy at two levels. The L4-L5 interspace was involved 19 times, and the L5-S1 interspace 10 times. Slipped vertebral apophysis was diagnosed in 4 patients (15%). Twelve of the 26 patients (46%) had a first-degree relative with a history of lumbar disc herniation. OUTCOME MEASURES: Telephone interviews provided follow-up data for 26 patients. Results were classified as excellent, good, moderate, or poor according to current symptom status, the need for additional surgery, the Oswestry Disability Index, and back and leg pain scores. RESULTS: The average time from surgery to follow-up was 8.9 years (range 3-21 years). At follow-up, the clinical results were excellent in 13 patients (50%), good in 4 (15%), moderate in 8 (31%), and poor in 1 (4%). Four subjects (15%) underwent a subsequent disc excision in the lumbar region, and one of them later underwent fusion. CONCLUSIONS: Discectomy provides satisfactory clinical results in young patients with disc herniation. The rate of reintervention (15%) is comparable to that in adults, indicating that discectomy for young patients should be approached similarly to that in adults.  相似文献   
3.
4.
Authors'' reply     
Jennie  Ngai  Ilya  Kreynin 《Paediatric anaesthesia》2007,17(4):403-403
  相似文献   
5.
The mammalian spinal cord contains a locomotor central pattern generator (CPG) that can produce alternating rhythmic activity of flexor and extensor motoneurones in the absence of rhythmic input and proprioceptive feedback. During such fictive locomotor activity in decerebrate cats, spontaneous omissions of activity occur simultaneously in multiple agonist motoneurone pools for a number of cycles. During these 'deletions', antagonist motoneurone pools usually become tonically active but may also continue to be rhythmic. The rhythmic activity that re-emerges following a deletion is often not phase shifted. This suggests that some neuronal mechanism can maintain the locomotor period when motoneurone activity fails. To account for these observations, a simplified computational model of the spinal circuitry has been developed in which the locomotor CPG consists of two levels: a half-centre rhythm generator (RG) and a pattern formation (PF) network, with reciprocal inhibitory interactions between antagonist neural populations at each level. The model represents a network of interacting neural populations with single interneurones and motoneurones described in the Hodgkin-Huxley style. The model reproduces the range of locomotor periods and phase durations observed during real locomotion in adult cats and permits independent control of the level of motoneurone activity and of step cycle timing. By altering the excitability of neural populations within the PF network, the model can reproduce deletions in which motoneurone activity fails but the phase of locomotor oscillations is maintained. The model also suggests criteria for the functional identification of spinal interneurones involved in the mammalian locomotor pattern generation.  相似文献   
6.
Epiphyseal chondrodysplasia, Miura type (ECDM) is a skeletal dysplasia with tall stature and distinctive skeletal features caused by heterozygous NPR2 pathogenic variants. Only four families have been reported. We present a family with five affected individuals (mother, three sons, and daughter). The mother's phenotype was relatively mild: borderline tall stature and elongated halluces operated during childhood. The children were remarkably more severely affected with tall stature, scoliosis, and elongated toes and fingers leading to suspicion of Marfan syndrome. Progressive valgus deformities (at the hips, knees, and ankles) were the main complaints and necessitated orthopedic investigations and surgery. Radiographs showed coxa valga, scoliosis, multiple pseudoepiphyses of the fingers and toes with uneven elongation of the digits and ankle valgus. The two older brothers underwent osteotomies and guided growth for axial deformities and arthrodesis for elongated halluces. Genetic testing confirmed the clinical diagnosis of ECDM: all affected individuals had a heterozygous c.2647G>A (p.Val883Met) NPR2 variant in a highly conserved region in the carboxyl‐terminal guanylyl cyclase domain. This two‐generation family elucidates the clinical and radiological variability of the disease. These rare cases are important to gain further understanding of the fundamental processes of growth regulation.  相似文献   
7.
The capacity of anion-radicals of aromatic ketones to initiate polymerization of acrolein, methacrolein and crotonic aldehyde is studied. It is established with the aid of spectral and chemical methods that the polymerization is initiated mainly by electron transfer to the monomer.  相似文献   
8.
Assessment of heart sounds is the cornerstone of cardiac examination, but it requires a stethoscope, skills and experience, and a direct contact with the patient. We developed a contactless, machine-learning assisted method for heart-sound identification and quantification based on the remote measurement of the reflected laser speckle from the neck skin surface in healthy individuals. We compare the performance of this method to standard digital stethoscope recordings on an example task of heart-beat sound biometric identification. We show that our method outperforms the stethoscope even allowing identification on the test data taken on different days. This method might allow development of devices for remote monitoring of cardiovascular health in different settings.  相似文献   
9.
Open in a separate window OBJECTIVESThe appropriate approach for surgical repair of coarctation of the aorta with a ventricular septal defect (VSD) remains controversial. This study evaluated the outcomes of primary repair of VSDs with periventricular device closure without cardiopulmonary bypass through a left thoracotomy in patients without arch hypoplasia.METHODSWe selected 21 patients aged <1 year, including 7 neonates, who underwent repair of coarctation of the aorta with periventricular device closure of a VSD.RESULTSThe median occluder size was 6 (range, 5–8) mm. The median mechanical ventilation time was 14 (range, 2–68) h, and the median duration of hospital stay was 11 (range, 7–16) days. No reoperations were required to correct VSD shunting, and the median residual shunt size was 1 (range, 1–2) mm. The median follow-up period was 13 (range, 4–31) months. No late deaths were reported, and no haemodynamically significant pressure gradient at the anastomotic site was observed. The median distal aortic arch z-score was 0.39 (range, −0.1–to 0.9). Only 1 patient had a permanent pacemaker implanted towards the end of the follow-up period.CONCLUSIONSPeriventricular device closure can be used safely for closure of VSD in children with coarctation of the aorta without a hypoplastic aortic arch, even in neonates, to reduce the risk of prolonged cardiopulmonary bypass. This hybrid approach can be performed with a low incidence of rhythm disturbances and residual shunting. However, a meticulous assessment of the VSD anatomy is essential to avoid any unfavourable events.  相似文献   
10.
STUDY OBJECTIVE: To evaluate the efficacy of intraperitoneal nebulization of ropivacaine on pain relief during and after gynecologic laparoscopic procedures including a review of the literature. DESIGN: Double-blinded, randomized, controlled, clinical trial (Canadian Task Force classification I). SETTING: University hospital ambulatory gynecoendoscopic department. PATIENTS: Forty patients (20 patients in each arm) undergoing elective gynecologic same-day outpatient laparoscopic surgery including unilateral/bilateral salpingo-oophorectomy or unilateral/bilateral ovarian cystectomy. INTERVENTIONS: The study group received 10 mL of 1% ropivacaine and the control group received 10 mL of sterile water by intraperitoneal nebulization. During surgery, vital signs were recorded and summarized. Postoperatively patients were followed up for 24 hours including visual analog scale scores and analgesic use. MEASUREMENTS AND MAIN RESULTS: No significant differences existed between the groups during surgery and at the recovery department in terms of arterial blood pressure (p = .42) or heart rate (p = .60). Regarding postoperative analgesia, no difference existed between the groups in terms of morphine consumption (p = .52) or other analgesics (p = .53). No significant difference existed between the groups in postoperative visual analog scale scores including visceral, abdominal wall, and shoulder pain during rest and during cough at the different time frames (30, 60, and 120 minutes and 6 and 24 hours after surgery). CONCLUSION: Our study is the first to examine the effects of intraperitoneal nebulization of ropivacaine throughout laparoscopic gynecologic procedures on patients undergoing general anesthesia. Nebulization of 100 mg of ropivacaine under our specific regimen of anesthesia does not improve patients' outcome in terms of intraoperative and postoperative pain along with consumption of analgesics. Further research with other regimens is required.  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