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   350篇
  免费   20篇
  国内免费   4篇
耳鼻咽喉   32篇
儿科学   2篇
妇产科学   1篇
基础医学   50篇
临床医学   26篇
内科学   52篇
皮肤病学   9篇
神经病学   7篇
特种医学   8篇
外国民族医学   1篇
外科学   68篇
综合类   11篇
预防医学   10篇
眼科学   7篇
药学   36篇
中国医学   2篇
肿瘤学   52篇
  2023年   1篇
  2022年   5篇
  2021年   22篇
  2020年   4篇
  2019年   6篇
  2018年   8篇
  2017年   8篇
  2016年   10篇
  2015年   11篇
  2014年   12篇
  2013年   18篇
  2012年   23篇
  2011年   23篇
  2010年   14篇
  2009年   13篇
  2008年   32篇
  2007年   37篇
  2006年   26篇
  2005年   15篇
  2004年   9篇
  2003年   7篇
  2002年   10篇
  2001年   9篇
  2000年   7篇
  1999年   8篇
  1998年   1篇
  1997年   3篇
  1996年   2篇
  1995年   3篇
  1993年   1篇
  1992年   4篇
  1991年   2篇
  1990年   4篇
  1989年   2篇
  1986年   4篇
  1985年   3篇
  1978年   1篇
  1977年   1篇
  1973年   2篇
  1972年   3篇
排序方式: 共有374条查询结果,搜索用时 15 毫秒
1.
INTRODUCTION: Radiofrequency (RF) tissue ablation has been tried safely and effectively in the West as percutaneous local tissue ablation therapy. We present our experience with this technique in malignant lesions. METHODS: RF tumor ablation was done using an RF generator (Berchtold; Germany) generating 35-50 RF watts of power output. The RF needle was placed in the tumor under image guidance (n = 22) or at open surgery (n = 1). Around 1500 watts/cm3 RF energy was delivered to the tumor. Over 21 months, 23 patients underwent the procedure for 73 lesions, including metastatic liver lesions (n = 21) and locally advanced inoperable carcinoma of pancreas (n = 2). RESULTS: All lesions less than 3 cm in size (n = 15) and 39% of lesions 3-4 cm in size (17/44) had complete necrosis. Residual tumor was seen in 27/44 lesions (61%) 3-4 cm in size and in all 14 lesions more than 4 cm in size. There was no mortality or major morbidity. There were two minor complications (ascites 1, pleural effusion 1). Of 21 patients treated for liver metastases, 10 are still alive (6-month survival 19/21 [90%] and 12-month survival 11/17 [64.7%]). Only 2 of 32 (6.2%) lesions with complete necrosis had local recurrence. CONCLUSION: RF tumor ablation is a safe and effective local tissue ablative method in Indian patients.  相似文献   
2.
Retropharyngeal abscesses were fairly common in preantibiotic era but the advent of antibiotics has reduced the overall incidence of these abscesses. They still continue to occur specially in developing world and carry significant morbidity and even mortality if not managed properly. The prevalence of this abscess in the young children pose a bigger challenge, as the examination of oral cavity is difficult. Emphasis is placed on the age, sex, type, and duration of symptoms, bacteriology, methodology of diagnosis, therapy and complications. With proper antibiotic cover and surgical management, majority of patients today survive without major residual squeal. Hereby we present a series of 15 cases of retropharyngeal abscess.  相似文献   
3.
4.
Pancreatic adenocarcinoma is believed to develop from histologically identifiable intraductal lesions known as pancreatic intraepithelial neoplasias (PanINs) that undergo a series of architectural, cytologic, and genetic changes, a progression model similar to the adenoma-carcinoma sequence in the colon. The apomucin MUC4 has been implicated in invasive pancreatic adenocarcinoma. MUC4 expression is not detectable at the RNA level in normal pancreas but is detectable at high levels in invasive pancreatic adenocarcinoma. We documented the pattern of expression of MUC4 in PanINs by studying a series of 71 PanIN lesions immunohistochemically using a new monoclonal antibody to MUC4. Five (17%) of 30 PanIN-1 lesions, 10 (36%) of 28 PanIN-2 lesions, 11 (85%) of 13 PanIN-3 lesions, and 25 (89%) of 28 invasive adenocarcinomas labeled with the MUC4 antibody used in the study. In addition, afew nonneoplastic lesions labeled with the MUC4 antibody, including reactive ducts in chronic pancreatitis, atrophic ducts filled with inspissated secretions, and ducts showing squamous metaplasia. Our data help establish the patterns of MUC4 expression in neoplastic precursors in the pancreas and add further support to the progression model for pancreatic adenocarcinoma.  相似文献   
5.
6.
The adsorption of carbofuran on sandy clay loam and silt loam soils has been studied at 30 and 50 degrees C. Adsorption data for both soils are in close agreement with the Freundlich isotherms and yield "S" class isotherms. The order of adsorption of carbofuran is in accordance with the partial molal free energy changes and conforms to the mobility of carbofuran in different soils. The thermodynamic constant (K0) and standard free energy (delta G degrees), enthalpy (delta H degrees), and entropy changes (delta S degrees) have also been calculated for predicting the nature of adsorption.  相似文献   
7.
8.
Mycoplasma pneumoniae, a self-replicating cell wall-deficient prokaryote, has a differentiated terminal organelle that is essential for cytadherence and gliding motility. P30, an important protein associated with the terminal organelle, is required for the cytadherence and virulence of M. pneumoniae. P30 is a transmembrane protein with an intracytoplasmic N terminus and an exposed C terminus. In the present study, we amplified and sequenced the full-length p30 gene of Mycoplasma pneumoniae directly from 18 Indian asthmatic patients. Sequence diversity was observed in the p30 genes from 16 clinical samples when the sequences were compared with the sequence of strain M-129. We also successfully expressed a fragment of the p30 gene (P30B) that includes the complete C-terminal proline-rich amino acid sequences in different Escherichia coli expression systems. The maltose binding protein (MBP)-P30B fusion protein was recognized by M. pneumoniae-infected patient sera in immunoblots, and the protein was immunogenic in mice. We further analyzed the reactivity of the MBP-P30B fusion protein with patient sera in an enzyme-linked immunosorbent assay (ELISA) and compared it with the reactivity obtained with a commercial kit (the Serion ELISA Classic kit). The sensitivity and the specificity of the in-house ELISA were 78.57% and 89.47%, respectively. This study suggests that the P30 protein can be used as an antigen along with other adhesin proteins for the immunodiagnosis of M. pneumoniae infection.  相似文献   
9.
10.
Herein, rare-earth manganite, La0.67Sr0.33MnO3, has been prepared by a citric acid-assisted sol–gel auto-combustion method at a maintained pH value of 11. Room-temperature X-ray diffraction (RT-XRD) data analysis revealed a rhombohedral structure for the sample with the space group R3c, which was further confirmed by synchrotron radiation X-ray diffraction (SR-XRD). Rietveld refinement was carried out for both spectra, which confirmed the SR-XRD and RT-XRD results and the various structural parameters. To determine any of the phase transitions in the sample, temperature-dependent X-ray diffraction corresponding to the temperatures of 100 K, 200 K, 250 K, and 325 K was carried out, and no new phase was found. Temperature-dependent Raman characterization confirmed the metallic phase of the sample with the reduced Jahn–Teller distortion. Scanning electron microscopy confirmed the growth in the grain size as a result of a high sintering temperature. Compositional verification was conducted using energy-dispersive analysis of X-ray diffraction (EDAX). Low-temperature dc resistivity measurement showed a metal-insulator transition temperature (TMI) of ≈178 K. The DSC-specific heat measurement shows the ferromagnetic metallic nature where heat capacity increases with an increase in temperature.

Herein, rare-earth manganite, La0.67Sr0.33MnO3, has been prepared by a citric acid-assisted sol–gel auto-combustion method at a maintained pH value of 11.  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