全文获取类型
收费全文 | 549篇 |
免费 | 40篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 16篇 |
妇产科学 | 12篇 |
基础医学 | 59篇 |
口腔科学 | 15篇 |
临床医学 | 52篇 |
内科学 | 120篇 |
皮肤病学 | 15篇 |
神经病学 | 20篇 |
特种医学 | 20篇 |
外科学 | 90篇 |
综合类 | 6篇 |
一般理论 | 1篇 |
预防医学 | 47篇 |
眼科学 | 5篇 |
药学 | 53篇 |
中国医学 | 9篇 |
肿瘤学 | 46篇 |
出版年
2023年 | 7篇 |
2022年 | 16篇 |
2021年 | 28篇 |
2020年 | 20篇 |
2019年 | 29篇 |
2018年 | 35篇 |
2017年 | 17篇 |
2016年 | 18篇 |
2015年 | 25篇 |
2014年 | 21篇 |
2013年 | 35篇 |
2012年 | 46篇 |
2011年 | 35篇 |
2010年 | 18篇 |
2009年 | 13篇 |
2008年 | 33篇 |
2007年 | 18篇 |
2006年 | 24篇 |
2005年 | 36篇 |
2004年 | 27篇 |
2003年 | 16篇 |
2002年 | 19篇 |
2001年 | 10篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1991年 | 7篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1977年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有592条查询结果,搜索用时 15 毫秒
1.
Brian A Haluska Robert Fathi Leanne Jeffriess Rodel Leano Stephane G Carlier Thomas H Marwick 《Journal of the American Society of Echocardiography》2004,17(2):195-202; quiz 203-4
BACKGROUND: Brachial artery reactivity (BAR), carotid intima-media thickness (IMT), and applanation tonometry for evaluation of total arterial compliance may provide information about preclinical vascular disease. We sought to determine whether these tests could be used to identify patients with coronary artery disease (CAD) without being influenced by their ability to identify those at risk for CAD developing. METHODS: We studied 100 patients and compared 3 groups: 35 patients with known CAD; 34 patients with symptoms and risk factors but no CAD identified by stress echocardiography (risk group); and 31 control subjects. BAR and IMT were measured using standard methods, and total arterial compliance was calculated by the pulse-pressure method from simultaneous radial applanation tonometry and pulsed wave Doppler of the left ventricular outflow. Ischemia was identified as a new or worsening wall-motion abnormality induced by stress. RESULTS: In a comparison between the control subjects and patients either at risk for developing CAD or with CAD, the predictors of risk for CAD were: age (P =.01); smoking history (P =.002); hypercholesterolemia (P =.002); and hypertension (P =.004) (model R = 0.82; P =.0001). The independent predictors of CAD were: IMT (P =.001); BAR (P =.04); sex (P =.005); and hypertension (P =.005) (model R = 0.80; P =.0001). CONCLUSION: IMT, BAR, and traditional cardiovascular risk factors appear to identify patients at risk for CAD developing. However, only IMT was significantly different between patients at risk for developing CAD and those with overt CAD. 相似文献
2.
Devi Kanikanti Padmalatha Rao Kanikanti V. Ranga Baveja Srikrishan Fathi Marc Roth Marc 《Pharmaceutical research》1989,6(4):313-317
Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C
max, higher values of t
max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well. 相似文献
3.
We describe a 3-year-old boy who presented with dysuria and urinary retention. The diagnostic work-up (USS, MRI, urethrocystoscopy), suggested a polypoid lesion at the bladder base, originating from the verumontanum. Histology showed the lesion to be a fibroepithelial polyp. A rare cause of urinary retention in childhood must be considered in the differential diagnosis. 相似文献
4.
Sonal Dubey D.P. Jindal Poonam Piplani Louse C. Young Behrooz Fathi Alan L. Harvey 《Medicinal chemistry research》2005,14(4):229-240
This study reports the synthesis of steroidal quaternary ammonium compounds 11 and 12, with quaternary nitrogen at position 3 and 16 of the steroid nucleus in 5α-epiandrosterone series; along with their neuromuscular
blocking activity using chick biventer cervicis muscle preparation. The compound 12 was found to be five times more potent than 11 in reducing twitch response to nerve stimulations, indicating the importance of extended interonium distances and 17-acetoxy
function for potent antagonist activity. 相似文献
5.
6.
Nasr-Esfahani MH Razavi S Vahdati AA Fathi F Tavalaee M 《Journal of assisted reproduction and genetics》2008,25(5):197-203
PURPOSE: To compare the efficiency of routine sperm selection method with HA-selection procedure for fertilization rate, embryo development, implantation and pregnancy rates as well as evaluating the relationship between HA-binding ability with sperm protamine deficiency and DNA fragmentation. METHODS: Semen samples were obtained from the 50 couples undergoing ICSI. The percentage of fertilization rate, cleavage and quality of embryos compared between two procedures (routine sperm selection and HA-binding selection). The semen samples were assessed for DNA fragmentation and protamine deficiency by sperm chromatin dispersion (SCD) test and Chromomycin A3 (CMA3) staining, respectively. RESULTS: A significant inverse correlation was observed between percentage of HA binding with protamine deficiency, DNA fragmentation and abnormal sperm morphology (P < 0.05). Furthermore, in current study, oocytes inseminated by HA sperm selection procedure had significantly higher fertilization rate (P < 0.05). While the pregnancy and implantation rates were insignificantly increased. CONCLUSION: The results suggest that normal sperm have higher chance to bind HA and therefore, HA sperm selection procedure may select sperm with normal protamine content and low DNA fragmentation, but to confirm the effect of HA sperm selection on the ICSI outcome requires further studies. 相似文献
7.
Nihal Fathi Samar H. Goma Nadia M. Ismail Abeer M. Ghandour Sally S. Youssef Nisreen A. Mohammed Eman Mosad 《The Egyptian Rheumatologist》2018,40(1):45-49
Background
Systemic sclerosis (SSc) is an autoimmune connective tissue disease with vascular, fibrotic and immune changes of skin and some internal organs. Anti-heterogeneous nuclear ribonucleoproteins (anti-hnRNP) were found in SSc patients.Aim of the work
To assess anti-hnRNP A1 and A2 autoantibodies in limited SSc patients and to find their relation to clinical and hand radiographic characteristics.Patients and methods
26 limited SSc patients and 16 matched control were studied. Skin thickness was scored according to the modified Rodnan skin score method (mRss) and radiologic examination by plain X-ray of the hand and wrist was performed anti-hnRNP A1 and A2 were measured in patients and control.Results
All patients were females with a mean age of 37.5 ± 11.24 years and mean disease duration of 7.84 ± 1.19 years. 96.2% of cases showed juxta-articular osteoporosis, 38.5% with marginal erosions, 73.1% with surface erosions, 42.3% with subchondral cyst, 42.3% with metacarpophalangeal subluxation, 11.5% with marginal sclerosis, 80.8% with resorption of distal phalanges, 38.5% with resorption of distal ulna and 34.6% with calcinosis. Anti-hnRNPA1 was positive in all the patients but the anti-hnRNPA2 was positive in 21 (80.8%). Anti-hnRNP A1 and A2 showed significant difference between patients and control (5.66 ± 4.18 ng/ml vs 2.88 ± 0.82; p < 0.01 and 1.82 ± 0.36 vs 0.73 ± 0.08; p < 0.02, respectively). There was no significant correlation between the markers with the mRss or radiographic changes.Conclusion
Joint affection in SSc is more frequent than expected. Anti-hnRNP A1 and anti hnRNP A2 antigens may be useful markers for SSc patient although no significant relation was found with radiologic findings. 相似文献8.
Maha Ibrahim Metwally Mohammad Abd Alkhalik Basha Ghada Adel AbdelHamid Mohamad Gamal Nada Reham Ramadan Ali Reem Abdel Fattah frere Al Shaimaa Fathi Elshetry 《The British journal of radiology》2021,94(1120)
Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T1 weighted and axial T2 weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies. 相似文献
9.
H.?Fathi H.?Martiny P.-G.?Jost-BrinkmannEmail author 《Journal of orofacial orthopedics》2015,76(2):143-151
Objectives
The purpose of this study was to test the cleaning effect of three commercially available effervescent tablet products on acrylic resin surfaces compared to water as control medium.Methods
A total of 20 volunteers were instructed to wear a vacuum-formed maxillary splint continuously for 96 h. Each splint incorporated four resin discs in the palate area. Each of these PMMA (polymethyl methacrylate) discs was split into two specimens which were analyzed upon removing the splint after the 4-day period. One specimen per disc was analyzed uncleaned and one after cleaning, using one of the investigated tablet products according to the manufacturer’s recommendations or water as control medium. The outcomes of cleaning were evaluated with the modified ortho-phthaldialdehyde (OPA) method by determining the amounts of surface protein.Results
Significant differences in relative (%) protein removal were noted between all three tablet products and water, and fittydent super® was significantly more effective in removing biofilm than Kukis®. No significant differences were observed between fittydent super® and NitrAdine® Ortho&Junior? or NitrAdine® Ortho&Junior? and Kukis®.Conclusion
The modified OPA method proved to be successful in examining protein-containing contaminations on the specimens, and the effervescent products tested were more effective than pure water in removing contaminants from orthodontic appliances. These results are, however, confined to soft plaque not older than 4 days.10.