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   554篇
  免费   38篇
  国内免费   7篇
耳鼻咽喉   9篇
儿科学   12篇
妇产科学   11篇
基础医学   78篇
口腔科学   8篇
临床医学   44篇
内科学   123篇
皮肤病学   8篇
神经病学   45篇
特种医学   15篇
外科学   71篇
综合类   2篇
预防医学   21篇
眼科学   8篇
药学   86篇
中国医学   1篇
肿瘤学   57篇
  2023年   1篇
  2022年   9篇
  2021年   30篇
  2020年   12篇
  2019年   17篇
  2018年   20篇
  2017年   21篇
  2016年   18篇
  2015年   27篇
  2014年   18篇
  2013年   37篇
  2012年   48篇
  2011年   55篇
  2010年   20篇
  2009年   21篇
  2008年   36篇
  2007年   24篇
  2006年   37篇
  2005年   43篇
  2004年   24篇
  2003年   31篇
  2002年   24篇
  2001年   3篇
  2000年   3篇
  1999年   3篇
  1998年   4篇
  1997年   2篇
  1996年   1篇
  1994年   2篇
  1993年   3篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1981年   1篇
排序方式: 共有599条查询结果,搜索用时 31 毫秒
101.
102.
A 60-year-old female presented to a local hospital with a chief complaint of melena. Since she was found to have a neoplastic lesion in the rectum on endoscopy, she was referred to our hospital. Barium-enema examination and endoscopy showed a 5-cm type-2 lesion proximal to the dentate line, which was diagnosed by biopsy as a moderately differentiated adenocarcinoma. Pelvic CT and MRI showed lower rectal wall thickening with pararectal lymphadenopathy, and FDP-PET showed increased uptake in these sites. Under a diagnosis of cT3, cN2, M0, Stage III b cancer, she started with preoperative chemoradiotherapy, consisting of 50 Gy in 25 fractions and oral UFT (400 mg)/Uzel (75 mg). After therapy, the tumor showed only a 2-cm ulceration, and FDG-PET revealed no abnormal uptake. Under a diagnosis of cT1, cN0, M0, Stage I cancer, super-low anterior resection of the rectum with D2 lymphadenectomy was performed. Histopathological examination showed that cancer cells forming a glandular structure had completely disappeared, leaving a fibrous scar, consistent with a Grade 3 (pCR).  相似文献   
103.

Background

There is a need for less invasive techniques for preoperative identification of axillary lymph node (ALN) metastases.

Method

Patients underwent ultrasonography (US) and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT), and then US-guided fine needle aspiration cytology (FNAC) and/or sentinel lymph node (SLN) biopsy were performed based on the US findings of the ALNs. Subsequently, patients with positive FNAC as well as those with positive SLN underwent axillary lymph node dissection (ALND). Postoperatively, removed SLNs and ALNs were examined histologically.

Results

Fifty (85 %) of 59 patients with positive 18F-FDG uptake in the axilla had axillary metastases, but 18F-FDG uptake results were false-positive in 9 (15 %) cases. On the other hand, 29 patients with positive FNAC underwent ALND without the need for SLN biopsy, while the remaining 20 patients with negative FNAC as well as 249 patients with negative US findings underwent SLN biopsy. Subsequently, 68 patients with positive SLN underwent ALND.

Conclusions

Positive FDG uptake in the axilla does not always indicate axillary metastasis. US-guided FNAC is useful to avoid unnecessary ALND in patients with positive 18F-FDG uptake. However, SLN biopsy is needed in patients with negative US findings of the ALNs and those with negative FNAC.
  相似文献   
104.
105.

Objectives

To investigate whether rice pads can eliminate lingering fat signals of the complex surface shape of both hands that occur with chemical shift selective (CHESS) at 1.5 T and 3.0 T.

Materials and methods

T1-weighted images were obtained with CHESS using 1.5 T and 3.0 T systems. The same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. The fat-suppression effects were classified into four categories and scored for images, and visual evaluations were performed by one radiologist and one radiologic technologist.

Results

At 1.5 T, the mean evaluation score was 1.55 for images obtained without rice pads and 3.50 for images obtained with rice pads. At 3.0 T, the mean evaluation score was 1.10 for images obtained without rice pads and 3.20 for images obtained with rice pads. With both systems, images obtained with the rice pads showed significantly better fat suppression effects than images obtained without rice pads (P < 0.0001, P < 0.0001).

Conclusions

It was confirmed that lingering fat signals are eliminated and good fat-suppressed images are obtained with the use of rice pads at 1.5 T and 3.0 T. Rice pads are therefore useful with at 1.5 T and 3.0 T, which are currently becoming more widely used.  相似文献   
106.
Abstract

We examined the changes in the heart of rats at the early stages of streptozotocin (STZ)-induced diabetes, and whether azuki bean extract (ABE) could influence these changes. The experimental diabetic rats received 0 or 40?mg/kg of ABE orally for 4?weeks, whereas the control group rats received distilled water. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and expression of proteins associated with peroxisomal FA β-oxidation as well as oxidative stress markers were examined. The levels of peroxisomal ACOX1 and catalase of the diabetic groups were significantly higher than those in the control group. The levels of p62, phosphorylated-p62 (p-p62) and HO-1 in the STZ group were significantly higher than those in the control group, and the levels of p-p62, HO-1, and 8-OHdG were significantly lower by ABE administration. The STZ-induced early diabetes increases the levels of proteins related to peroxisomal FA β-oxidation and oxidative stress markers in hearts. ABE protects diabetic hearts from oxidative damage.  相似文献   
107.
Intraoperative radiographic examination of breast specimens is commonly performed to confirm excision of image-detected breast lesions, but it is not reliable for assessing margin status. A more accurate method of intraoperative breast specimen imaging is needed. Micro-CT provides quantitative imaging parameters, image rotation, and virtual “slicing” of intact breast specimens. We explored the use of micro-CT for assessment of a variety of clinical breast specimens. Specimens were evaluated with a table top micro-CT scanner, Skyscan 1173 (Skyscan, Belgium), with a 40–130 kV, 8 W X-ray source. Skyscan software for 3D image analysis (Dataviewer and CTVox) was employed to review 3D graphics of specimens. Scanning for 7 min and another 7 min for image reconstruction provided the desired resolution for breast specimens. Breast lumpectomy specimens, shaved cavity margins, mastectomy specimens, and axillary lymph nodes were imaged by micro-CT. The micro-CT images could be rotated in all directions and cross sections of internal portions of specimens could be visualized from any angle. This provided information about spatial orientation of masses and calcifications relative to margins in intact lumpectomy specimens. Micro-CT is a potentially useful tool for assessment of breast cancer specimens, allowing real-time analysis of tumor location in breast lumpectomy specimens or shaved cavity margins. Micro-CT may also be useful for assessing sentinel lymph nodes and mastectomy specimens.  相似文献   
108.
Currently, it is standard practice that patients with negative sentinel lymph nodes (SLNs) do not undergo axillary lymph node dissection (ALND), whereas ALND is mandated in those with positive SLNs. However, the Z0011 trial showed that ALND could be safely omitted in selected patients with positive SLNs. This article presents a review and discussion of the current role and practice of ALND in the surgical management of breast cancer. A review of the English-language medical literature was performed using the MEDLINE database and cross-referencing major articles on the subject. It may be concluded that ALND can be avoided not only in patients with negative SLNs but also in those with positive SLNs who undergo breast-conserving therapy with whole-breast irradiation and appropriate systemic therapy. However, the omission of ALND would be indicated only in patients with a low axillary tumor burden. On the other hand, ALND remains a standard method of treating regional disease not only in patients with clinically positive nodes but also in other SLN-positive patients who do not meet the above criteria. Although the role of ALND has been limited to the prevention of axillary recurrence, SLN biopsy with whole-breast irradiation and systemic therapy can replace ALND in patients with a low axillary tumor burden.  相似文献   
109.
110.
Allergic photocontact dermatitis due to suprofen   总被引:1,自引:0,他引:1  
We report 5 cases of photocontact dermatitis due to suprofen, a nonsteroidal anti-inflammatory drug introduced to the Japanese market in 1989, and available as a 1% ointment. The patients developed pruritic eczematous lesions after applying the ointment for from 2 weeks to 3 months. All 5 patients reacted positively to photopatch testing with ultraviolet A (UVA) and suprofen down to 0.1-0.01% pet., and 3 patients showed positive reactions with ultraviolet B (UVB) and suprofen down to 1.0-0.1%. Moreover, all patients showed a cross-reaction with tiaprofenic acid, which has a very similar chemical structure to suprofen. However, there was no cross-reaction between suprofen and ketoprofen. Prescribers should be aware of the existence of photocontact sensitivity due to these drugs.  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