全文获取类型
收费全文 | 3168篇 |
免费 | 205篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 63篇 |
儿科学 | 202篇 |
妇产科学 | 51篇 |
基础医学 | 344篇 |
口腔科学 | 132篇 |
临床医学 | 213篇 |
内科学 | 637篇 |
皮肤病学 | 88篇 |
神经病学 | 236篇 |
特种医学 | 143篇 |
外科学 | 479篇 |
综合类 | 85篇 |
一般理论 | 1篇 |
预防医学 | 108篇 |
眼科学 | 149篇 |
药学 | 212篇 |
中国医学 | 20篇 |
肿瘤学 | 219篇 |
出版年
2023年 | 36篇 |
2022年 | 80篇 |
2021年 | 166篇 |
2020年 | 80篇 |
2019年 | 114篇 |
2018年 | 129篇 |
2017年 | 92篇 |
2016年 | 123篇 |
2015年 | 110篇 |
2014年 | 179篇 |
2013年 | 176篇 |
2012年 | 254篇 |
2011年 | 222篇 |
2010年 | 135篇 |
2009年 | 76篇 |
2008年 | 120篇 |
2007年 | 151篇 |
2006年 | 150篇 |
2005年 | 130篇 |
2004年 | 112篇 |
2003年 | 69篇 |
2002年 | 63篇 |
2001年 | 47篇 |
2000年 | 62篇 |
1999年 | 56篇 |
1998年 | 29篇 |
1997年 | 25篇 |
1996年 | 20篇 |
1995年 | 11篇 |
1994年 | 9篇 |
1992年 | 22篇 |
1991年 | 22篇 |
1990年 | 30篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 23篇 |
1986年 | 20篇 |
1985年 | 16篇 |
1984年 | 18篇 |
1983年 | 12篇 |
1982年 | 8篇 |
1978年 | 11篇 |
1977年 | 10篇 |
1976年 | 9篇 |
1975年 | 16篇 |
1974年 | 11篇 |
1973年 | 10篇 |
1972年 | 10篇 |
1971年 | 11篇 |
1970年 | 8篇 |
排序方式: 共有3382条查询结果,搜索用时 15 毫秒
81.
Piyush Kumar Sharma Garima Shukla Anupama Gupta Vinay Goyal Achal Srivastava Madhuri Behari 《Annals of Indian Academy of Neurology》2013,16(2):146-150
There is an increasing awareness for recognition of sleep disorders in India; however, there is still a huge gap in the number of people suffering from various sleep disorders, in the community versus those visiting hospital clinics for the same. Ours is a neurology services-based sleep disorders clinic, which has evolved successfully over the last decade. In this study, we aimed to evaluate the changes in referral patterns and distribution of various sleep disorders in the patients presenting to the clinic.
Materials and Methods:
This is a retrospective chart review-based study on all patients seen over an 8-year period, divided into 2 groups comprising of patients seen during the first 4 years versus those seen over the next 4 years. Only those patients who had the sleep disorder as their presenting manifestation and those who had been formally interviewed with a pre-structured questionnaire detailing about the main features of the common sleep disorders according to the ICSD-R were included. Patients, in whom the sleep disorder could be clearly attributable to another neurological or systemic disorder, were excluded. Statistical analysis was carried out to identify the differences between the two groups as regards the distribution of various sleep disorders and other clinical data.Results:
Among 710 patients registered in the clinic, 469 were included for analysis and 222 patients formed group 1 while 247 formed group 2. The main differences observed were in the form of a clear increase in the percentage of patients with sleep-related breathing disorders, sleep-related movement disorder, and the hypersomnias on comparison of distribution over the first 4 years versus the last 4 years; while a clear decline was seen in the number of patients with insomnia and parasomnias. A 3-fold increase was observed in the number of patients in whom polysomnography was obtained.Conclusion:
The distribution of various sleep disorders as seen in a neurology service-based sleep clinic is demonstrated in this study. Increasing referrals for sleep-disordered breathing, restless legs syndrome, and fewer referrals for insomnia and parasomnias might reflect on changing physician and patient awareness in our community. 相似文献82.
Goyal M Marya K Jhamb A Chawla S Sonoo PR Singh V Aggarwal A 《The British journal of oral & maxillofacial surgery》2012,50(6):556-561
Our aim was to compare the use of a conventional rotary handpiece and a Piezosurgical unit for extraction of lower third molars. We studied 40 patients, who were allocated alternately to have the third molar removed with either the handpiece or the Piezosurgical unit. Pain, trismus, and oedema were evaluated at baseline and then postoperatively, together with paraesthesiae, on postoperative days 1, 3, 5, 7, and 15. Damage to surrounding tissue was checked on the same day whereas dry socket was evaluated from postoperative day 3 onwards. More patients complained of pain in the conventional group, they also required more analgesics, and they developed trismus more often than in the Piezosurgery group. There was also significantly more postoperative swelling in the conventional group. Patients were also evaluated using the subjective Postoperative Symptom Severity (PoSSe) scale. Our results suggest that apart from some inherent limitations with the Piezotome, it is a valuable alternative for extraction of third molars. 相似文献
83.
Metta Vinod Leta Valentina Mrudula Kandadai Rukmini Prashanth L. K. Goyal Vinay Borgohain Rupam Chung-Faye Guy Chaudhuri K. Ray 《Journal of neurology》2022,269(3):1154-1163
Journal of Neurology - Gastrointestinal symptoms and gut dysbiosis may occur before the onset of motor symptoms in Parkinson's disease (PD). Prediagnostic and prodromal features, such as... 相似文献
84.
85.
Tacrolimus combined with corticosteroids versus Modified Ponticelli regimen in treatment of idiopathic membranous nephropathy: Randomized control trial 下载免费PDF全文
86.
The objective of the present study is to improve iron bioavailability using high-density gastroretentive pellets of zero valent iron nanoparticles (ZVINPs). ZVINPs were prepared by the chemical reduction method and were characterized for surface morphology, surface charge, and thermal properties. High-density gastroretentive pellets of iron nanoparticles were prepared using spheronization technique. Pellets were characterized for its micromeritic properties, in vitro drug release, and ex vivo permeability. The pharmacokinetic parameters, organ distribution, and toxicity of the optimized pellets were investigated in Wistar rats. In vivo results revealed more than 2-fold increases in oral bioavailability of iron by pellets compared to plane ferrous sulfate. Toxicological studies of the carriers indicated no evidence of liver damage in acute treatment; however, few complications were observed in chronic treatment groups. These results indicated that ZVINPs pellets successfully improve the oral iron bioavailability but need to obtain more information on repeated dose toxicity to initiate the clinical evaluation of investigational products. 相似文献
87.
88.
Nephron injury induced by diagnostic ultrasound imaging at high mechanical index with gas body contrast agent 总被引:1,自引:0,他引:1
Williams AR Wiggins RC Wharram BL Goyal M Dou C Johnson KJ Miller DL 《Ultrasound in medicine & biology》2007,33(8):1336-1344
The right kidney of anesthetized rats was imaged with intermittent diagnostic ultrasound (1.5 MHz; 1-s trigger interval) under exposure conditions simulating those encountered in human perfusion imaging. The rats were infused intravenously with 10 microL/kg/min Definity (Bristol-Myers Squibb Medical Imaging, Inc., N. Billerica, MA, USA) while being exposed to mechanical index (MI) values of up to 1.5 for 1 min. Suprathreshold MI values ruptured glomerular capillaries, resulting in blood filling Bowman's space and proximal convoluted tubules of many nephrons. The re-establishment of a pressure gradient after hemostasis caused the uninjured portions of the glomerular capillaries to resume the production of urinary filtrate, which washed some or all of the erythrocytes out of Bowman's space and cleared blood cells from some nephrons into urine within six hours. However, many of the injured nephrons remained plugged with tightly packed red cell casts 24 h after imaging and also showed degeneration of tubular epithelium, indicative of acute tubular necrosis. The additional damage caused by the extravasated blood amplified that caused by the original cavitating gas body. Human nephrons are virtually identical to those of the rat and so it is probable that similar glomerular capillary rupture followed by transient blockage and/or epithelial degeneration will occur after clinical exposures using similar high MI intermittent imaging with gas body contrast agents. The detection of blood in postimaging urine samples using standard hematuria tests would confirm whether or not clinical protocols need to be developed to avoid this potential for iatrogenic injury. 相似文献
89.
Biesbrock AR Bartizek RD Walters PA Warren PR Cugini M Goyal CR Qaqish J 《The Journal of clinical dentistry》2007,18(4):106-111
OBJECTIVE: To evaluate the safety and plaque removal efficacy of an advanced rotating-oscillating power toothbrush relative to a sonic toothbrush with either a standard or compact brush head. METHODOLOGY: Two studies used a randomized, examiner-blind, two-treatment, crossover design. In Study 1, subjects were instructed to use their first randomly assigned toothbrush for five to seven days and then, after abstaining from all oral hygiene for 24 hours, were assessed with the Rustogi, et al. Modified Navy Plaque Index. They then brushed for two minutes and post-brushing plaque scores were recorded. Subjects were assigned to the alternate toothbrush and the procedures were repeated. In Study 2, subjects alternated using both brushes for approximately 10 days, then had four study visits three to four days apart (some variability based on patient scheduling). In Study 1, Oral-B Triumph with a FlossAction brush head and Sonicare Elite 7300 with a full-size, standard head were compared in a two-treatment, two-period crossover study. Study 2 compared Oral-B Triumph with a FlossAction brush head and Sonicare Elite 7300 with a compact head in a two-treatment, four-period crossover study. RESULTS: Fifty subjects completed Study 1 and 48 completed Study 2. All brushes were found to be safe and significantly reduced plaque after a single brushing. In Study 1, Oral-B Triumph was statistically significantly (p < 0.001) more effective in plaque removal than Sonicare Elite 7300 with the full-size brush head: whole mouth = 24% better, marginal = 31% better, approximal = 21% better. In Study 2, Oral-B Triumph was statistically significantly (p < 0.001) more effective than Sonicare Elite 7300 with the compact brush head: whole mouth = 12.2% better, marginal = 14.6% better, approximal = 12% better. CONCLUSION: Oral-B Triumph with its rotation-oscillation action was significantly more effective in single-use plaque removal than Sonicare Elite 7300 with its side-to-side sonic action when fitted with either a standard or a compact brush head. 相似文献
90.
Neural Control of the Lower Esophageal Sphincter INFLUENCE OF THE VAGUS NERVES 总被引:2,自引:5,他引:2 下载免费PDF全文
We performed studies in the opossum to define the influence of the vagi in the control of lower esophageal sphincter (LES) function. Bilateral vagotomy caused transient sphincter hypertension which was prevented by phentolamine and by atropine. Stimulation of the peripheral end of vagus, after bilateral cervical vagotomy, caused relaxation of the LES over a wide range of frequency and intensity of electrical stimulation. The relaxation was less marked at the lower frequencies of stimulation, and atropine treatment did not enhance this relaxation. In other experiments, atropine treatment reversed the rise in gastric (fundic) pressure with the vagal stimulation, but atropine did not enhance the degree of LES relaxation. Stimulation of the central end of the vagus caused an increase in LES pressure due to a centrally mediated reflex; the efferents for this motor response were not present in the vagi, as the reflex contraction persisted after bilateral vagotomy. The LES contraction with the stimulation of the vagal afferents was antagonized by phentolamine as well as by atropine. These studies suggest that: (a) the vagi do not mediate any cholinergic excitatory influences to the LES and the vagal influence of the sphincter is entirely inhibitory; (b) the vagi carry afferent fibres for a centrally mediated neural reflex which contracts the LES, but the efferent path of this reflex arc does not lie in the vagi. 相似文献