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   7975篇
  免费   473篇
  国内免费   41篇
耳鼻咽喉   100篇
儿科学   484篇
妇产科学   83篇
基础医学   933篇
口腔科学   160篇
临床医学   640篇
内科学   1644篇
皮肤病学   127篇
神经病学   517篇
特种医学   177篇
外科学   1159篇
综合类   244篇
一般理论   3篇
预防医学   386篇
眼科学   506篇
药学   710篇
  1篇
中国医学   43篇
肿瘤学   572篇
  2023年   59篇
  2022年   163篇
  2021年   335篇
  2020年   191篇
  2019年   235篇
  2018年   282篇
  2017年   184篇
  2016年   211篇
  2015年   265篇
  2014年   371篇
  2013年   429篇
  2012年   588篇
  2011年   537篇
  2010年   325篇
  2009年   272篇
  2008年   451篇
  2007年   393篇
  2006年   387篇
  2005年   355篇
  2004年   278篇
  2003年   248篇
  2002年   235篇
  2001年   154篇
  2000年   154篇
  1999年   128篇
  1998年   69篇
  1997年   52篇
  1996年   30篇
  1995年   29篇
  1994年   26篇
  1992年   92篇
  1991年   79篇
  1990年   70篇
  1989年   73篇
  1988年   68篇
  1987年   58篇
  1986年   60篇
  1985年   56篇
  1984年   42篇
  1983年   23篇
  1982年   23篇
  1979年   39篇
  1977年   31篇
  1975年   33篇
  1974年   29篇
  1973年   26篇
  1972年   32篇
  1971年   25篇
  1970年   21篇
  1968年   21篇
排序方式: 共有8489条查询结果,搜索用时 10 毫秒
1.
Purpose:To evaluate the rate of compliance and the reasons for loss to follow-up in Indian patients with diabetic macular edema (DME), age-related macular degeneration (AMD), and retinal vein occlusion (RVO) being treated with anti-vascular endothelial growth factor (VEGF) therapy.Methods:This was a retrospective single-center study. Patients with DME, AMD, or RVO were eligible if they initiated anti-VEGF therapy between January 2013 and December 2017. Patients'' data were obtained from hospital electronic records, including the number of injections received, visits, details of follow-up, missed appointments, and reasons for loss to follow-up (>365 days).Results:A total of 648 patients were eligible for the study, of which 334 (51.54%) patients were lost to follow-up. Overall, 343 (64.96%) were males and the overall mean (SD) age was 66.40 (7.44) years. A total of 376 (58.0%) patients had a history of diabetes and 364 (56.2%) patients had a history of hypertension. Further, 127 (38.0), 112 (33.5), and 95 (28.4) had DME, AMD, and RVO, respectively and were lost to follow-up. The most commonly reported reason for loss to follow-up was “non-affordability” (n = 120; 41.1%) followed by “no improvement in vision” (n = 83; 28.4%). “No improvement in vision” (42.2%) and “non-affordability” (37.5%) were higher among patients with DME. No association was found in gender- and treatment-wise distribution of reasons for loss to follow-up.Conclusion:The results showed that around half of the patients with DME, AMD, and RVO were lost to follow-up to intravitreal anti-VEGF therapy, and the most common factors were “non-affordability” and “no improvement in vision.”  相似文献   
2.
BACKGROUND: Penetrating injuries of the perineum are rare but very dangerous. Since the genitourinary and colorectal organs may be injured, how to evaluate surgical management of the injury is very important.METHODS: The present report presents a case of penetrating injury of the perineum by a wooden stick when the patient fell on the upright wooden stick from a tree. The three feet long stick entered the perineal region just left lateral to the anal opening. Upon reaching the thoracic cavity, it broke and only a foot stick was left in the subcutaneous plane. These injuries are potentially serious with risk of damage to multiple organs. Exploratory laprotomy was done, and bladder injury was repaired. The entry wound and the track of stick was thoroughly washed and allowed for secondary intention healing.RESULTS: The post operative period was uneventful and the patient recovered fully.CONCLUSION: Meticulous evaluation and surgical management of perineal injuries are the key to prevent devastating complications.  相似文献   
3.
INTRODUCTION: Autoimmune hepatitis (AIH) is a well-defined entity in the West but there are sparse Indian data on this disease. AIM: To study the clinical profile and response to treatment of Indian patients with AIH. METHODS: This is a part retrospective and part prospective study of 50 patients (median age 48 years, range 11-82; 43 women) seen between 1995 to 2001, diagnosed to have AIH as per the revised scoring system. Clinical and laboratory profile, response to treatment, and complications of treatment were analyzed. RESULTS: AIH accounted for 6% of all patients with liver disease seen during the period. The presenting symptoms were gastrointestinal in 43 and non-gastrointestinal in 7, with median symptom duration of 6 months (range 2 weeks to 40 years). Forty patients (80%) had chronic liver disease. Associated illnesses were present in 28 patients. Twenty-six patients were classified as definite and the rest as probable AIH. Forty-nine patients had Type 1 AIH. Five patients had overlap syndrome. Forty-five patients (90%) received immunosuppressive therapy. Twelve of 18 patients receiving only prednisolone and 21 of 27 patients receiving prednisolone and azathioprine combination responded. Thirteen (26%) patients had therapy-related complications (infectious 5, non infectious 8) with two treatment-related deaths. CONCLUSION: Type 1 AIH was the predominant type of AIH. The majority of patients with AIH presented with chronic liver disease. There was good response to immunosuppressive therapy. Therapy-related complications occurred in one-fourth of patients.  相似文献   
4.
BackgroundMesenteric internal hernia (MIH) is the most common cause of small bowel obstruction (SBO) after laparoscopic Roux-en-Y gastric bypass. Because MIH is a potentially life-threatening complication, we hypothesized that elective repair of MIH before developing acute SBO could decrease morbidity in this population.MethodsThe records of 702 consecutive patients undergoing primary laparoscopic Roux-en-Y gastric bypass from January 2002 and August 2007 were retrospectively reviewed to determine the incidence and etiology of SBO. During the last 9 months of the study, we offered elective laparoscopy to any patient who presented to us with symptoms of intermittent SBO.ResultsOf the 702 patients, 27 (3.8%) developed acute SBO. Of these 27 patients, 15 (55%) had obstruction related to an MIH. Nearly all patients had a typical history of intermittent abdominal pain, nausea, and bloating before developing acute SBO. Elective laparoscopy was offered to 11 patients with symptoms of intermittent SBO. Two patients who refused subsequently underwent operations for acute SBO. MIH was found at elective laparoscopic exploration in all cases. Of the 9 patients undergoing elective surgery, 3 (33%) had small bowel volvulus.ConclusionSBO due to MIH after laparoscopic Roux-en-Y gastric bypass is typically preceded by symptoms of intermittent obstruction. Patients who have these herald symptoms should promptly be offered elective laparoscopic exploration. Elective repair of MIH can be performed safely and expeditiously.  相似文献   
5.
Nasal Cytogram is a simple, economical and reliable investigation. Although its utility was recognised as early s1927, it has not gained much popularity. Here an attempt is madeto assess the efficacy of nasal cytology in the light of histology, to diagnose various nasal conditions.127 cases of common rhinological problem were studied at Govt. Medical College, Nagpur. This investigation was found to be simple, reliable & economical.  相似文献   
6.
7.
Insulin and the insulin-like growth factors IGF-I and IGF-II are thought to exert their mitogenic effects in cultured chick embryo fibroblasts and human skin fibroblasts via IGF receptors rather than via insulin receptors. These effects appear to be mediated by the type I subtype of IGF receptor, which is structurally similar to the insulin receptor and exhibits significant cross-reactivity with insulin. As a first step in our long-range goal of defining those features of the IGF-I and IGF-II molecules that confer enhanced mitogenic activity and reactivity with these mitogenic type I IGF receptors, we have prepared two hybrid insulin-IGF molecules and examined their mitogenic and binding activities: (1) A27-insulin, containing an elongated 27-residue A-chain (in which the 6-residue D-domain of IGF-II was added to the carboxy-terminus of the 21-residue A-chain of insulin) combined with the B-chain of insulin; and (2) A insulin-B IGF-1, containing the A-chain of insulin and the synthetic 30-residue B-domain of IGF-I. Both hybrid molecules stimulated DNA synthesis and inhibited 125I-IGF-I binding to type I IGF receptors in both chick embryo and human fibroblast cultures. A27-insulin had considerably greater mitogenic potency and binding potency than A insulin-B IGF-I. Neither hybrid molecule was more potent in these assays than insulin, indicating that the presence of D IGF-II or B IGF-I by itself was not sufficient to increase the mitogenic potency of insulin in fibroblasts. By contrast, A insulin-B IGF-I showed enhanced reactivity with an antiserum to IGF-I. A27-insulin retained significant insulin-like metabolic activity despite the presence of the D-domain of IGF-II.  相似文献   
8.
Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision.  相似文献   
9.
10.
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