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   4646篇
  免费   144篇
  国内免费   21篇
耳鼻咽喉   48篇
儿科学   109篇
妇产科学   54篇
基础医学   356篇
口腔科学   68篇
临床医学   288篇
内科学   1198篇
皮肤病学   185篇
神经病学   243篇
特种医学   125篇
外科学   941篇
综合类   16篇
预防医学   135篇
眼科学   137篇
药学   166篇
  1篇
中国医学   3篇
肿瘤学   738篇
  2024年   29篇
  2023年   76篇
  2022年   125篇
  2021年   197篇
  2020年   121篇
  2019年   131篇
  2018年   142篇
  2017年   136篇
  2016年   171篇
  2015年   148篇
  2014年   190篇
  2013年   218篇
  2012年   324篇
  2011年   362篇
  2010年   193篇
  2009年   155篇
  2008年   220篇
  2007年   262篇
  2006年   249篇
  2005年   246篇
  2004年   186篇
  2003年   205篇
  2002年   176篇
  2001年   51篇
  2000年   37篇
  1999年   34篇
  1998年   33篇
  1997年   22篇
  1996年   20篇
  1995年   26篇
  1994年   20篇
  1993年   15篇
  1992年   24篇
  1991年   17篇
  1990年   20篇
  1989年   23篇
  1988年   23篇
  1987年   22篇
  1986年   12篇
  1985年   12篇
  1984年   9篇
  1983年   9篇
  1977年   9篇
  1975年   9篇
  1974年   10篇
  1973年   9篇
  1971年   13篇
  1970年   7篇
  1969年   8篇
  1966年   9篇
排序方式: 共有4811条查询结果,搜索用时 0 毫秒
101.

Purpose

Ghrelin is mainly secreted from the stomach and plays a role in appetite, weight gain, and the promotion of a positive energy balance. The levels of ghrelin decrease immediately after gastrectomy. We herein investigated the effect of the administration of synthetic ghrelin to treat postoperative severe weight loss in a prospective, one-arm clinical trial to develop new strategies for weight gain.

Methods

Ten patients (four distal gastrectomy and six total gastrectomy) received ghrelin treatment. Eligibility criteria included patients who underwent gastrectomy more than 1 year previously and 15 % body weight loss from the preoperative weight or a body mass index under 19. Synthetic human ghrelin (3 μg/kg) was administered to the patients twice a day for 1 week. Oral intake of calories, appetite [evaluated using the visual analog scale (VAS)], and body weight before and during administration of ghrelin were compared.

Results

There was a significant difference in the oral food intake before and during treatment (before treatment: 1236 ± 409 kcal vs. during treatment: 1398 ± 365 kcal, p = 0.039), and the VAS for appetite significantly improved with each day of ghrelin administration (p < 0.05). Significant amounts of body weight were gained (39.5 ± 6.8 vs. 40.1 ± 6.9, p = 0.037).

Conclusions

The administration of synthetic ghrelin improved the food intake and was effective for treating appetite loss and body weight loss. Synthetic ghrelin may be a promising new therapy for severe body weight loss following gastrectomy.
  相似文献   
102.
Objective: Hemorrhagic shock is a relatively common occurrence in the postpartum period. In our hospital, we performed abdominal ultrasonography using the focused assessment with sonography for obstetrics (FASO) technique (a modified version of FAST). The aim of the present study was to determine the reference values for the ultrasonographic findings to establish the criteria for the diagnosis of a postpartum hemorrhage and severe shock using the FASO.

Methods: The present prospective cohort study included all postpartum women who vaginally delivered singleton infants. Abdominal ultrasonography was performed after delivery. The observation points of ultrasonography were as follows: (1) the diameter of the intrauterine cavity, (2) the pouch of Douglas, (3) Morison’s pouch, (4) between the spleen and kidney, and (5) the diameter of the inferior vena cava.

Results: One hundred and eighty-two postpartum women were included in this study. The mean uterine cavity was 9.8?±?7.3?mm. An echo-free space in the pouch of Douglas was observed in three cases, in one case in Morison’s pouch, and not observed between the spleen and kidney. A negative correlation was found between the volume of bleeding and IVCi (p?=?0.0008, r2=??0.061) and IVCe (p?<?0.0001, r2=??0.106).

Conclusions: The present study establishes criteria that can be used to diagnose a postpartum hemorrhage or severe shock using the FASO.  相似文献   
103.
There is cumulative evidence that neuregulin 1 (NRG1) is a susceptibility gene for schizophrenia. Postmortem studies on brains from schizophrenia patients have revealed changes in the mRNA expression levels of v-erb-b2 erythroblastic leukemia viral oncogene homolog 3 (ERBB3), one of the NRG1 receptor genes. These observations suggest that NRG1-ERBB signaling is involved in the pathogenesis of schizophrenia. To assess whether the ERBB3 gene could be implicated in vulnerability to schizophrenia, we conducted a case-control (399 patients and 438 controls) association study in Japanese subjects. There were no significant association between the polymorphisms or haplotypes of ERBB3 and schizophrenia. The present study shows that ERBB3 does not play a major role in conferring susceptibility to schizophrenia in the Japanese population.  相似文献   
104.
Annals of Surgical Oncology - Colorectal cancer (CRC) is a major cause of cancer-related deaths. Metastasis is enhanced through epithelial-mesenchymal transition (EMT), a process primarily induced...  相似文献   
105.
106.

Purpose

LigaSure, a bipolar electronic vessel sealing system, has become popular in abdominal surgery but few clinical studies have been conducted to evaluate its effectiveness in radical gastrectomy for gastric cancer.

Methods

In this multicenter, prospective, randomized controlled trial, patients with curative gastric cancer were randomly assigned to undergo gastrectomy either with LigaSure or a conventional technique.

Results

Of the 160 patients enrolled, 80 were randomized to the LigaSure group and 78 to the conventional group. Patient characteristics were well balanced in the two groups. There were no significant differences between the LigaSure and conventional groups in blood loss (288 vs. 260 ml, respectively; P = 0.748) or operative time (223 and 225 min, respectively; P = 0.368); nor in the incidence of surgical complications or duration of postoperative hospital stay. In a subgroup analysis of patients who underwent gastrectomy that preserved the distal part of the greater omentum, the use of LigaSure significantly reduced blood loss (179 vs. 245 ml; P = 0.033), and the duration of the operation (195 vs. 221 min; P = 0.039).

Conclusions

LigaSure did not contribute to reducing intraoperative blood loss, operative time, or other adverse surgical outcomes. The usefulness of the device may be limited to a specific part of the surgical procedure in open gastrectomy.  相似文献   
107.
Esophagus - Endoscopic diagnosis of the invasion depth of superficial esophageal squamous cell carcinoma (ESCC) is an important determinant of the treatment strategy. The three endoscopic imaging...  相似文献   
108.
109.
Background/Objectives: This study aimed to elucidate the efficacy of CT findings and perioperative characteristics to predict post-pancreatectomy hemorrhage (PPH): a critical complication after pancreaticoduodenectomy.MethodsThe records of 590 consecutive patients who underwent pancreaticoduodenectomy at three institutes between 2012 and 2018 were included. The presence of a vascular wall abnormality or ascites with high density (vascular abnormality) on postoperative day (POD) 5–10 contrast-enhanced CT (early CT), perioperative characteristics, and any PPH or pseudoaneurysm formation (PPH events) were analyzed through a multivariate analysis.ResultsPPH events occurred in 48 out of 590 patients (8%). The vascular abnormality on early CT and the C-reactive protein (CRP) value on POD 3 were independent risk factors for PPH events after POD5 (vascular abnormality: odds ratio 6.42, p = 0.001; CRP on POD 3: odds ratio 1.17, p = 0.016). The sensitivity of vascular abnormality for PPH events was 24% (7/29), and the positive predictive value was 30% (7/23). The combination of vascular abnormality and a high CRP value (≥15.5 mg/dL) on postoperative day 3 had a higher positive predictive value of 64% (7/11) than the vascular abnormality alone. None of the seven PPH events that occurred more than one month after surgery were foreseen via early CT.ConclusionThe combination of vascular abnormality and high CRP value was associated with increasing risk of PPH events after pancreaticoduodenectomy, but the low sensitivity of early CT must be noted as an important shortcoming. The normal findings on early CT could not eliminate the risk of late PPH.  相似文献   
110.
We report a rare case of disseminated carcinomatosis of the bone marrow from rectal cancer with disseminated intravascular coagulation (DIC). A 65-year-old man was admitted with melena and low back pain at rest. X-ray examination showed rectal cancer with multiple bone metastases. Laboratory examination showed severe anemia and DIC. Histologic examination showed disseminated carcinomatosis of the bone marrow. The DIC was considered to be caused by disseminated carcinomatosis of the bone marrow from rectal cancer, and we immediately started treatment with anti-DIC therapy and anticancer chemotherapy with the modified FOLFOX6 regimen (mFOLFOX6). After some response to therapy, the patient''s general condition deteriorated, and he died 128 days after admission. This is the first English report showing disseminated carcinomatosis of the bone marrow from colorectal cancer treated with mFOLFOX6.Key words: Bone marrow neoplasms, Rectal neoplasms, Disseminated intravascular coagulationBone metastases diffusely invading the bone marrow with disseminated intravascular coagulation (DIC) and microangiopathic hemolytic anemia (MHA) tend to accompany solid tumors; this condition is called disseminated carcinomatosis of the bone marrow,1 and it is associated with an extremely poor prognosis. Among solid tumors, DIC is most commonly associated with breast cancer, prostate cancer, and lung cancer2,3; carcinomatosis arising from colorectal cancer is rare.Herein we report on a patient with disseminated carcinomatosis of the bone marrow with rectal cancer who developed acute DIC and was treated with a modified FOLFOX6 regimen (mFOLFOX6). We also review 11 similar previously reported cases.410  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