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   1940篇
  免费   103篇
  国内免费   2篇
耳鼻咽喉   18篇
儿科学   113篇
妇产科学   49篇
基础医学   173篇
口腔科学   27篇
临床医学   96篇
内科学   325篇
皮肤病学   35篇
神经病学   117篇
特种医学   206篇
外科学   402篇
综合类   38篇
预防医学   94篇
眼科学   130篇
药学   130篇
中国医学   12篇
肿瘤学   80篇
  2023年   15篇
  2022年   48篇
  2021年   63篇
  2020年   33篇
  2019年   31篇
  2018年   56篇
  2017年   28篇
  2016年   36篇
  2015年   51篇
  2014年   76篇
  2013年   76篇
  2012年   121篇
  2011年   140篇
  2010年   67篇
  2009年   48篇
  2008年   110篇
  2007年   112篇
  2006年   77篇
  2005年   82篇
  2004年   66篇
  2003年   77篇
  2002年   65篇
  2001年   52篇
  2000年   50篇
  1999年   49篇
  1998年   14篇
  1997年   10篇
  1996年   6篇
  1995年   9篇
  1993年   8篇
  1992年   22篇
  1991年   33篇
  1990年   23篇
  1989年   44篇
  1988年   29篇
  1987年   24篇
  1986年   28篇
  1985年   19篇
  1984年   14篇
  1983年   16篇
  1982年   12篇
  1981年   7篇
  1980年   11篇
  1979年   15篇
  1978年   14篇
  1977年   9篇
  1973年   7篇
  1972年   4篇
  1971年   6篇
  1970年   4篇
排序方式: 共有2045条查询结果,搜索用时 0 毫秒
91.
92.
We report the case of a 25-year-old male patient who presented with complaints of redness, photophobia, and decreased vision in the right eye of a week's duration. Slit-lamp biomicroscopic examination revealed a cream-colored, irregular elevated inferior iris mass, extending on to the anterior lens surface. Differential diagnoses of a fungal granuloma, a medulloepithelioma, and an amelanotic melanoma were considered. An excisional biopsy of the mass was performed through a superior clear corneal incision. Polymerase chain reaction analysis of the aqueous humor showed a positive pan fungal genome. Histopathology of the biopsied mass showed a giant cell granuloma with surrounding numerous branching, septate hyphae. Culture growth revealed Aspergillus fumigatus We report this case because of the rarity of Aspergillus iris granuloma as a primary presentation of endogenous Aspergillosis and review the relevant literature. Absence of a significant systemic history compounded the diagnostic dilemma in our patient. Definitive differentiation of this rare entity from a foreign body, amelanotic melanoma, and other inflammatory conditions such as sarcoidosis and tuberculosis, may be possible only on microbiological and histo-pathological evaluation.  相似文献   
93.
94.
The possible combination of specific physicochemical properties operating at unique sites of action within cells and tissues has led to considerable uncertainty surrounding nanomaterial toxic potential. We have investigated the importance of proteins adsorbed onto the surface of two distinct classes of nanomaterials (single-walled carbon nanotubes [SWCNTs]; 10-nm amorphous silica) in guiding nanomaterial uptake or toxicity in the RAW 264.7 macrophage-like model. Albumin was identified as the major fetal bovine or human serum/plasma protein adsorbed onto SWCNTs, while a distinct protein adsorption profile was observed when plasma from the Nagase analbuminemic rat was used. Damaged or structurally altered albumin is rapidly cleared from systemic circulation by scavenger receptors. We observed that SWCNTs inhibited the induction of cyclooxygenase-2 (Cox-2) by lipopolysaccharide (LPS; 1 ng/ml, 6 h) and this anti-inflammatory response was inhibited by fucoidan (scavenger receptor antagonist). Fucoidan also reduced the uptake of fluorescent SWCNTs (Alexa647). Precoating SWCNTs with a nonionic surfactant (Pluronic F127) inhibited albumin adsorption and anti-inflammatory properties. Albumin-coated SWCNTs reduced LPS-mediated Cox-2 induction under serum-free conditions. SWCNTs did not reduce binding of LPS(Alexa488) to RAW 264.7 cells. The profile of proteins adsorbed onto amorphous silica particles (50-1000 nm) was qualitatively different, relative to SWCNTs, and precoating amorphous silica with Pluronic F127 dramatically reduced the adsorption of serum proteins and toxicity. Collectively, these observations suggest an important role for adsorbed proteins in modulating the uptake and toxicity of SWCNTs and nano-sized amorphous silica.  相似文献   
95.
96.
Inhibin from human seminal plasma is structurally identical to sperm coating antigen. Using the flow cytometric technique it has been demonstrated that there is a positive correlation between initial motility of sperm and the amount of inhibin coated on the spermatozoal surface.  相似文献   
97.
Four regimens of prophylactic antibiotics were utilized in 122 consecutive patients of stages III and IV carcinoma of the upper aero-digestive tract undergoing major resections in a randomized single-blind study. Ampicillin, gentamicin, cephalexin and metronidazole were used in different combinations for periods of 5 or 10 days. A cephalexin-metronidazole protocol for 10 days was associated with lowest post-operative infection rate. Oral-oropharyngeal resection and use of pectoralis major myocutaneous flap were the most important factors contributing to infection.  相似文献   
98.
BACKGROUND AND PURPOSE: Transurethral microwave thermotherapy (TUMT) is an effective therapy for symptomatic benign prostatic hyperplasia (BPH), but the trade-off between the magnitude of clinical improvement and side effects and patient tolerance has limited its appeal to patients and urologists. This study, using the TherMatrx TMx-2000, a TUMT device that directly heats the transition zone to greater than 50 degrees C, has been focused on resolving these issues and developing a truly office-based therapy that is well tolerated with a benign post-treatment course. PATIENTS AND METHODS: This study was multi-institutional and designed as a blinded, randomized, and sham-controlled trial. A series of 200 patients with an AUA Symptom Index (AUASI) of >12, a peak flow rate of <12 mL/sec, and cystoscopic evidence of BPH were randomized 2:1 (active to sham) and treated in seven physician offices under a Food and Drug Administration-supervised and audited premarket approval protocol. No intravenous sedation was used in any patient. Follow-up for the sham-treatment group was 3 months, at which time, patients could cross over to an active treatment. A total of 119 patients have completed 1-year follow-up. RESULTS: The active and sham groups were statistically identical at baseline. The 1-hour total treatment was extremely well tolerated using urethral lidocaine and oral medications; not a single prostate block or parental dose of medication was required. The active-treatment group demonstrated a statistically significant reduction (p < 0.05) in AUASI at 3 months compared with sham treatment, with an AUASI decrease from 22.4 to 12.4 (n = 124) for active v 22.9 to 17 for sham (n = 62). For the 119 patients in the active arm who have reached 12 months, the AUASI has fallen to 10.6 points (47.1% decrease), and the peak flow rate has increased 5.0 mL/sec (58.1%). Postprocedure catheterization was typically 2 or 3 days, and the 16.8% of patients who failed their first voiding trial all voided within 1 week. No major adverse events such as stricture, rectal findings, or ejaculatory changes have been reported. CONCLUSIONS: This study demonstrates that the TherMatrx TMx-2000 TUMT effectively treats symptomatic BPH in the physician office with minimal morbidity.  相似文献   
99.
100.
Medulloepithelioma: a case report   总被引:2,自引:0,他引:2  
Histological, immunohistochemical, and CT morphological features of medulloepithelioma, a rare embryonal tumor of primitive neuroepithelium, are described.  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