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   1440篇
  免费   66篇
  国内免费   7篇
耳鼻咽喉   31篇
儿科学   83篇
妇产科学   25篇
基础医学   136篇
口腔科学   35篇
临床医学   98篇
内科学   360篇
皮肤病学   15篇
神经病学   91篇
特种医学   42篇
外科学   293篇
综合类   26篇
预防医学   55篇
眼科学   87篇
药学   81篇
中国医学   2篇
肿瘤学   53篇
  2023年   6篇
  2022年   25篇
  2021年   55篇
  2020年   33篇
  2019年   38篇
  2018年   43篇
  2017年   33篇
  2016年   36篇
  2015年   35篇
  2014年   58篇
  2013年   62篇
  2012年   82篇
  2011年   106篇
  2010年   50篇
  2009年   48篇
  2008年   63篇
  2007年   64篇
  2006年   85篇
  2005年   59篇
  2004年   62篇
  2003年   39篇
  2002年   53篇
  2001年   50篇
  2000年   47篇
  1999年   50篇
  1998年   17篇
  1997年   13篇
  1996年   8篇
  1995年   12篇
  1994年   6篇
  1992年   6篇
  1991年   12篇
  1990年   9篇
  1989年   7篇
  1988年   9篇
  1987年   7篇
  1986年   5篇
  1985年   8篇
  1984年   12篇
  1979年   6篇
  1978年   5篇
  1977年   6篇
  1975年   5篇
  1974年   8篇
  1973年   13篇
  1972年   6篇
  1971年   6篇
  1970年   6篇
  1969年   11篇
  1967年   5篇
排序方式: 共有1513条查询结果,搜索用时 31 毫秒
1.
Studies on the development of imaging agents for targeting neuroreceptors is an area of considerable interest owing to the limited availability of specific as well as selective radiolabeled agents. Therefore, with an aim of developing a receptor-specific agent, iminodiacetic acid (IDA) derivative of 5-hydroxy tryptamine viz., HTIDA has been synthesized. HTIDA could be radiolabeled with the synthon [(99m)Tc(CO)(3)(H(2)O)(3)](+) in >98% yield. The biodistribution studies in normal Swiss mice showed that the (99m)Tc(CO)(3)-HTIDA crosses the blood-brain barrier successfully with a brain uptake of 0.5%ID/g at 5min post injection. The other relevant observations from biodistribution studies included no significant uptake in any other organ and fast clearance from blood, lungs and liver.  相似文献   
2.
The increasing demands of clinical audit have resulted in the need for accurate data collection. The use of tumour maps allows standardization of the records of patients with head and neck cancer, which facilitates collation of data in multicentre studies and makes interdepartmental comparisons more meaningful. The aim of this study was to develop an improved standard set of tumour maps for recording the stage of head and neck tumours. A review of the existing tumour diagrams was performed to identify those anatomical areas that are not adequately represented or where ambiguity exists. The areas where improvements could be made were identified as: (1) the anterior commissure of the larynx; (2) axial and sagittal views of the larynx; (3) the pyriform fossa and cervical oesophagus; (4) the oropharynx and vallecula; (5) the nasal cavity and paranasal sinuses; and (6) cervical nodal involvement. A new set of tumour maps is presented in an attempt to correct some of the limitations of the existing diagrams.  相似文献   
3.
Modern medicine has been researching on cancer cell, cancer, hypertension, heart attack and so on without once defining any of these clearly. It swears by these terms much like mankind swears by sunset and sunrise, which are just not there. It is possible that the pet hobbyhorses of modern times, namely, gene, genetics, and heredity may belong to the above mythical group-entities that are logically absent, but whose illogic is strong enough to sustain research and publication world over. Gene, genetics and heredity have outlived their utility and must be replaced in near future by new concepts and terms.  相似文献   
4.
5.
BackgroundGiant cell myocarditis (GCM) has a poor prognosis without heart transplant, but post-transplant survival is unknown.PurposeTo describe the post-transplant survival of patients with GCM at a large transplant center.MethodsSeven patients underwent heart transplant for histologically confirmed GCM of the explanted heart. The median age was 59 years, and 43% (3 of 7) were female. All patients had cardiogenic shock, multiorgan failure, elevated troponin, and recurrent ventricular tachycardia, and some required mechanical circulatory support. All patients received rabbit antithymocyte globulin (rATG) in the perioperative period at a dose of 1.5 mg/kg daily for 1 to 5 days and 4 received intravenous immunoglobulin 1 g/kg daily for 2 days after rATG. All patients had early initiation of tacrolimus by first to third postoperative day depending on renal function, early mycophenolate, and high dose steroid. All were maintained using tacrolimus, mycophenolate, and prednisone.ResultsOne patient had asymptomatic recurrence of GCM at 3 months, managed by up-titration of tacrolimus, and had asymptomatic 2R cellular rejection at 4 months, managed with steroid bolus. No patient had high-grade rejection. One patient died at 267 days, possibly of GCM. Six of 7 (86%) remain alive at a median of 842 days (2.3 years) post transplant.ConclusionsPatients with GCM have excellent post-transplant survival with use of rATG and triple drug immunosuppressive therapy; however, some patients remain at risk for GCM recurrence after transplant, which may respond to augmented immunosuppression.  相似文献   
6.
7.
BACKGROUND: A total of 25 patients with tetralogy of Fallot and an important coronary artery crossing the right ventricular outflow tract underwent complete repair without use of an extracardiac conduit between January 1990 and December 1994. Repair was exclusively done by the transatrial or transatrial-transpulmonary approach. Age of these patients ranged from 1 to 12 years (mean 3.6 years). Three of the patients had already received a systemic to pulmonary artery shunt. METHODS: All patients reporting for follow-up (n = 18) were subjected to transthoracic echocardiography and, if required, cardiac catheterization and angiography. Right ventricle to pulmonary artery gradients were noted preoperatively, at discharge following repair and at follow-up study. RESULTS: Mean follow-up was 40.6 months (24 to 62 months). Mean early postoperative gradient was 23.5+/-13.4 mm Hg and 4 patients had significant (> 30 mm Hg) gradients. Mean late postoperative gradient was 20.6+/-12.4 mmHg and 2 patients had gradients greater than 30 mmHg. All the patients were in New York Heart Association functional class I at the time of last follow-up. CONCLUSIONS: Acceptable gradients across the right ventricular outflow tract are achievable following repair of tetralogy of Fallot in the presence of anomalous coronary artery across the right ventricular outflow tract using the transatrial or transatrial-transpulmonary approach. Most gradients were found not to vary significantly on subsequent follow-up.  相似文献   
8.
Purpose:Ripasudil hydrochloride hydrate (0.4%) is the first Rho-associated protein kinase (ROCK) inhibitor eye drop that lowers intraocular pressure (IOP) by increasing conventional aqueous outflow through the trabecular meshwork and Schlemm’s canal. We aimed to evaluate the safety and efficacy of ripasudil in patients using the maximum topical anti-glaucoma medications and with uncontrolled IOP.Methods:In our prospective interventional study, we enrolled 27 eligible and consenting patients (46 eyes) who presented to us between January 2021 and June 2021. Ripasudil 0.4% was added as adjunctive therapy to the ongoing glaucoma treatment. On follow-up visits at 7 days, 15 days, 1 month, 2 months, and 3 months, the visual acuity, IOP with applanation tonometer, anterior segment, and fundus were evaluated. The IOP before and after the use of ripasudil eye drops was compared by paired t-test.Results:Among the 27 patients, 18 were males and 9 were females. A statistically significant reduction in IOP was noted at all time durations (P < 0.00001) with the maximum reduction at 3 months with all patients achieving their target IOP. No patient developed any side effects necessitating the omission of ripasudil. The most common adverse event noted was conjunctival hyperemia (22 patients), which was mild and transient.Conclusion:Ripasudil showed additional IOP-lowering effect with other antiglaucoma medications and exhibited no significant side effects.  相似文献   
9.

Objective

To study the efficacy of uterine electrical stimulation (ES) with various parameters in delaying delivery in term- and preterm-laboring animals.

Study design

Catheters and electrodes, as well as ES electrodes, were sutured onto the uterine horn in day-15 pregnant rats. ES with various durations/frequencies (five sets of parameters) was tested from gestation day 21 to determine its effects on uterine contractility. The best set of ES parameters was applied in term (day 21) and preterm (day 18—labor induced) animals to determine the effects of ES on delivery.

Results

(1) Significant reduction in uterine contractions (0.54 ± 0.11 vs. 0.86 ± 0.08 contractions per minute, P < 0.001) was noted with ES of only one of the five sets of parameters (set #5 with pulse train of 10 s on and 10 s off, 28 ms pulse width, frequency of 30 Hz and amplitude of 4 mA); (2) ES with parameter set 5 delayed delivery by 12.5 h (P = 0.01) and reduced area under the curve of intrauterine pressure in mmHg s (311 ± 147.21 vs. 848.75 ± 350.38, P < 0.05) and AUC-electromyographic activity is area under rectified (i.e. absolute value) uterine EMG trace in mV s (145.25 ± 93.1 vs. 410 ± 182.46, P < 0.05) in the term rats; and (3) similar effects were noted with ES in preterm rats with a delay in delivery by 28 h (P < 0.001), and a decrease in IUP–AUC (intrauterine pressure–area under curve) (101.5 ± 55.45 vs. 551 ± 269.06, P = 0.017) and EMG–AUC (64.25 ± 43.63 vs. 172.5 ± 62.91, P = 0.03).

Conclusion

ES of the uterus with appropriate parameters inhibits uterine contractions and delays delivery in both term and preterm rats.  相似文献   
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