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   4862篇
  免费   234篇
  国内免费   28篇
耳鼻咽喉   47篇
儿科学   104篇
妇产科学   99篇
基础医学   480篇
口腔科学   101篇
临床医学   297篇
内科学   1302篇
皮肤病学   146篇
神经病学   239篇
特种医学   125篇
外科学   951篇
综合类   16篇
预防医学   95篇
眼科学   122篇
药学   236篇
  1篇
中国医学   3篇
肿瘤学   760篇
  2024年   8篇
  2023年   49篇
  2022年   72篇
  2021年   166篇
  2020年   96篇
  2019年   112篇
  2018年   126篇
  2017年   125篇
  2016年   150篇
  2015年   140篇
  2014年   173篇
  2013年   218篇
  2012年   343篇
  2011年   354篇
  2010年   203篇
  2009年   156篇
  2008年   233篇
  2007年   284篇
  2006年   269篇
  2005年   282篇
  2004年   236篇
  2003年   238篇
  2002年   226篇
  2001年   87篇
  2000年   82篇
  1999年   77篇
  1998年   54篇
  1997年   32篇
  1996年   25篇
  1995年   29篇
  1994年   25篇
  1993年   16篇
  1992年   35篇
  1991年   36篇
  1990年   31篇
  1989年   44篇
  1988年   28篇
  1987年   26篇
  1986年   27篇
  1985年   26篇
  1984年   35篇
  1983年   18篇
  1982年   17篇
  1981年   9篇
  1979年   9篇
  1978年   8篇
  1977年   12篇
  1974年   8篇
  1973年   10篇
  1971年   14篇
排序方式: 共有5124条查询结果,搜索用时 265 毫秒
1.
We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.  相似文献   
2.

Background

There were few studies assessed the postoperative sarcopenia in patients with cancers. The objective of present study was to assess whether postoperative development of sarcopenia could predict a poor prognosis in patients with adenocarcinoma of esophagogastric junction, (AEG) and upper gastric cancer (UGC).

Methods

Patients with AEG and UGC who were judged as non-sarcopenic before surgery were reassessed the presence of postoperative development of sarcopenia 6 months after surgery. Patients were divided into the development group or non-development group, and clinicopathological factors and prognosis between these two groups were analyzed.

Results

The 5-year overall survival rates were significantly poorer in the development group than non-development group (68.0% vs. 92.6%, P?=?0.0118). Multivariate analyses showed that postoperative development of sarcopenia was an independent prognostic factor for poor overall survival (P?=?0.0237).

Conclusions

Postoperative development of sarcopenia was associated with a poor prognosis in patients with AEG and UGC.  相似文献   
3.
EDITORIAL COMMENT: We accepted this case for publication to remind readers that although uterine rupture during labour in a primigravida is extremely uncommon it does occur, or at any rate nulliparas can develop abdominal pain and shock in labour with a haemoperitoneum resulting from a tear in a vein in the lower posterior uterine wall. When one sees the hugely dilated uterine and ovarian venous plexuses at Caesarean section it is easy to believe that bleeding from such a vessel during labour could be prodigious. This case suggests that a dilated vein with blood flow derangements may be the cause. Nonetheless, as the authors warn us, the necessary response is not a precise diagnosis, but rapid laparotomy. See also Editorial Comment to Chin MMS, Harvey JA, Duffy BL. Uterine rupture during labour in a primigravida. Aust NZ J Obstet Gynaecol 1996; 36: 210.  相似文献   
4.
PURPOSE: The purpose of this study was to examine changes of chewing movement and masticatory efficiency during the natural course of nonreducing disc displacement of the temporomandibular joint (TMJ). PATIENTS AND METHODS: The subjects were 15 patients who had been diagnosed with nonreducing disc displacement of the TMJ but had received no treatment. Chewing movement and masticatory efficiency were examined at the initial visit and at a mean follow-up of 21.7 months, using mandibular kinesiography and adenosine triphosphate ebteric-coated granules. As a control, 23 persons who had no current or previous TMJ symptoms were studied. RESULTS: The patients' clinical signs and symptoms tended to be alleviated during the follow-up period. In normal controls, chewing movement showed lateral excursion to the chewing side on both the right and left sides. In patients, chewing movement at the initial visit showed lateral excursion to the chewing side during chewing on the TMJ affected side, but no such deviation was noted during chewing on the TMJ unaffected side in the horizontal plane. However, chewing movement at follow-up became similar to that of controls. In patients, masticatory efficiency became better during the natural course, although that at follow-up did not always reach the control's level. CONCLUSION: In untreated patients with nonreducing disc displacement of the TMJ, chewing movement and masticatory efficiency tend to improve spontaneously.  相似文献   
5.
A 16-year-old man was admitted to our hospital with nausea, general fatigue, and consciousness disturbance along with extreme hyperammoniemia eight days after the onset of symptoms. Familial history and the high concentration of orotic acid in urine lead us to a diagnosis of OTCD. We immediately initiated intensive treatment such as continuous hemodiafiltration and sodium benzoate administration; however, the patient died twelve days after admission. Since OTCD is not so rare and can be found in all ages, it should be considered fundamental for evaluation of hyperammoniemia. This case suggested that for a better prognosis of OTCD patients it is very important to prevent such an onset, and to make an as early as possible diagnosis and start to treatment.  相似文献   
6.
7.
Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA.  相似文献   
8.
9.
Six normal men performed cycle ergometer exercise from 50 W to 125 W in a room maintained at 26 degrees C. Capsaicin was introduced by iontophoresis into the forearm skin. Forearm skin blood flow (FSBF) during graded exercises before and after capsaicin treatment was measured by laser Doppler flowmetry. Forearm skin blood flow before capsaicin treatment increased depending on the intensity of exercise. However, forearm skin blood flow 24 hours after capsaicin treatment scarcely increased during graded exercise. The cause of this capsaicin effect was discussed.  相似文献   
10.
In order to determine predictive factors of early seizures (ES) after acute stroke and to estimate prognosis, we retrospectively examined clinical data of 1,743 consecutive patients with acute ischemic stroke. The subjects were divided into two groups; an ES group (19 patients) and a non-ES group (1,724 patients). Multivariate statistical analysis revealed that the NIH-Stroke Scale score on admission (/10, OR, 1.1: 95% CI 1.04 to 1.13) and positive past history of cerebrovascular disease or brain injury (OR, 3.85: 95% CI 1.49 to 9.95) are significant factors to predict ES. There was no significant difference in the outcome between the two groups. A recurrence of seizures, after follow up for 4 to 40 months, was observed only in one patient with a history of ES.  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