全文获取类型
收费全文 | 7261篇 |
免费 | 356篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 177篇 |
妇产科学 | 136篇 |
基础医学 | 871篇 |
口腔科学 | 373篇 |
临床医学 | 494篇 |
内科学 | 1537篇 |
皮肤病学 | 199篇 |
神经病学 | 655篇 |
特种医学 | 159篇 |
外国民族医学 | 1篇 |
外科学 | 1107篇 |
综合类 | 35篇 |
一般理论 | 1篇 |
预防医学 | 689篇 |
眼科学 | 221篇 |
药学 | 395篇 |
中国医学 | 58篇 |
肿瘤学 | 455篇 |
出版年
2023年 | 51篇 |
2022年 | 97篇 |
2021年 | 243篇 |
2020年 | 128篇 |
2019年 | 192篇 |
2018年 | 244篇 |
2017年 | 142篇 |
2016年 | 166篇 |
2015年 | 181篇 |
2014年 | 270篇 |
2013年 | 324篇 |
2012年 | 581篇 |
2011年 | 555篇 |
2010年 | 320篇 |
2009年 | 299篇 |
2008年 | 477篇 |
2007年 | 541篇 |
2006年 | 438篇 |
2005年 | 445篇 |
2004年 | 385篇 |
2003年 | 380篇 |
2002年 | 375篇 |
2001年 | 66篇 |
2000年 | 62篇 |
1999年 | 83篇 |
1998年 | 62篇 |
1997年 | 45篇 |
1996年 | 32篇 |
1995年 | 28篇 |
1994年 | 19篇 |
1993年 | 25篇 |
1992年 | 18篇 |
1991年 | 23篇 |
1990年 | 28篇 |
1989年 | 34篇 |
1988年 | 27篇 |
1987年 | 23篇 |
1986年 | 17篇 |
1985年 | 19篇 |
1984年 | 13篇 |
1983年 | 17篇 |
1982年 | 21篇 |
1981年 | 14篇 |
1980年 | 17篇 |
1979年 | 18篇 |
1978年 | 12篇 |
1977年 | 11篇 |
1975年 | 10篇 |
1974年 | 8篇 |
1971年 | 7篇 |
排序方式: 共有7641条查询结果,搜索用时 15 毫秒
991.
992.
Cooper CP Saraiya M McLean TA Hannan J Liesmann JM Rose SW Lawson HW 《Journal of women's health (2002)》2005,14(8):670-678
The National Breast and Cervical Cancer Early Detection Program (NBCCEDP), administered by the Centers for Disease Control and Prevention (CDC), provides breast and cervical cancer screening to low-income women who are uninsured or underinsured. For women with three consecutive annual Pap tests with normal findings, the NBCCEDP supports extending the screening interval to every 3 years. Thirteen telephone focus groups were conducted with physician providers in 17 states and the District of Columbia to investigate familiarity with NBCCEDP's triennial Pap test policy, the Pap test intervals actually used, and the factors influencing screening interval selection. No participants were familiar with NBCCEDP's triennial Pap test policy, and none reported routinely extending the screening interval after three consecutive annual Pap tests with normal findings. Two patterns of screening interval use were reported: annual screeners continued performing yearly Pap tests, and selective extended screeners offered an extended interval to select patients. Annual and selective extended screeners reported that both unique and common factors influenced the screening intervals they used. The NBCCEDP has established its cancer screening priorities to focus limited resources on the goal of providing services to eligible women who have rarely or never been screened. Increased efforts are needed to educate physicians about the science supporting an extended Pap screening interval and overcome the barriers associated with its adoption. 相似文献
993.
Levy J Monos T Puterman M 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2005,40(4):506-508
BACKGROUND: We present an interventional case report of a rare occurrence of sphenoid sinus mucocele causing bilateral consecutive blindness with unilateral partial recovery after endoscopic surgery. METHODS: A 64-year-old woman with known sphenoid sinus mucocele and right blindness was referred because of an acute drop of vision to hand motion in her only-seeing left eye over 5 days. Imaging revealed a large mucocele enlarging the sphenoid sinus, eroding the base of the skull, protruding into the cranial cavity, and compressing the left optic nerve. RESULTS: Urgent endoscopic sphenoidotomy was performed. Several hours after the procedure, visual acuity was partially recovered in the left eye. INTERPRETATION: Sphenoid sinus mucoceles can cause bilateral blindness. A high index of suspicion and urgent imaging studies are necessary. Because visual recovery depends on prompt diagnosis and surgical intervention, a close collaboration between otolaryngologists and ophthalmologists is crucial. 相似文献
994.
995.
Mayor-Torroglosa S De la Villa P Rodríguez ME López-Herrera MP Avilés-Trigueros M García-Avilés A de Imperial JM Villegas-Pérez MP Vidal-Sanz M 《Investigative ophthalmology & visual science》2005,46(10):3825-3835
PURPOSE: To investigate the long-term effects of transient ligature of the ophthalmic vessels (LOV) on the inner and outer retina as well as on retinotectal projection, and whether brimonidine (BMD) has protective effects. METHODS: In adult rats, the left eye was subjected to 90 minutes of LOV. One hour before ischemia, 2 drops of saline alone (vehicle group) or saline containing 0.5% brimonidine (BMD group) were instilled in the left eye. The effects of LOV on the inner and outer retina were assessed with ERG recordings of a- and b-wave amplitudes at 1, 8, and 12 weeks after LOV and with analysis of layer thickness in paraffin sections. The retinotectal projection was orthogradely labeled with cholera toxin subunit B (CTB) injected in the left eye and measured in serial coronal sections of the superior colliculus. RESULTS: There were significant reductions in the mean b-wave amplitudes of the ischemic eyes at 8 and 12 weeks after LOV in the vehicle-treated group of animals, but not in the BMD-treated group. The thickness of the inner nuclear and inner plexiform layers of the vehicle-treated group of retinas had decreased to approximately 71% of the thicknesses in the BMD-treated groups. Three months after LOV, the mean volume of the retinotectal projection in the vehicle- or BMD-treated group of animals had decreased to approximately 54% or 83%, respectively, of the mean values found in the control group of animals. CONCLUSIONS: LOV induces degeneration of the inner retinal layers and the retinotectal projection 3 months after the insult. BMD administration significantly protected against LOV-induced retinal damage and degeneration of retinal projection. 相似文献
996.
Gastroprotective effect of the Mapuche crude drug Araucaria araucana resin and its main constituents
Schmeda-Hirschmann G Astudillo L Rodríguez J Theoduloz C Yáñez T 《Journal of ethnopharmacology》2005,101(1-3):271-276
The resin from the tree Araucaria araucana (Araucariaceae) has been used since pre-columbian times by the Mapuche amerindians to treat ulcers. The gastroprotective effect of the resin was assessed in the ethanol-HCl-induced gastric ulcer in mice showing a dose-dependent gastroprotective activity at 100, 200 and 300 mg/kg per os. The main three diterpene constituents of the resin, namely imbricatolic acid, 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid were isolated and evaluated for gastroprotective effect at doses of 50, 100 and 200 mg/kg. A dose-related gastroprotective effect with highly significant activity (P<0.01) was observed at doses up to 200 mg/kg. At 100 mg/kg, the highest gastroprotective activity was provided by 15-hydroxyimbricatolal and 15-acetoxyimbricatolic acid, all of them being as active as the reference drug lansoprazole at 20 mg/kg. The cytotoxicity of the main diterpenes as well as lansoprazole was studied towards human lung fibroblasts (MRC-5) and determined by the MTT reduction assay. A concentration-dependent cell viability inhibition was found with IC50 values ranging from 125 up to 290 microM. Our results support the traditional use of the Araucaria araucana resin by the Mapuche culture. 相似文献
997.
Lifshitz T Levy J Mahler O Levinger S 《Journal of cataract and refractive surgery》2005,31(7):1392-1395
PURPOSE: To report 5 eyes of peripheral sterile corneal infiltrates after refractive surgery. SETTING: Department of Ophthalmology, Soroka University Medical Center, Beer-Sheva, Israel, and Enaim Ophthalmological Center, Jerusalem, Israel. METHODS: Three patients had bilateral refractive procedures for correcting myopia. The procedures included laser epithelial keratectomy in 2 eyes, laser in situ keratomileusis (LASIK) in 2 eyes using a keratome, and LASIK in 1 eye using femtosecond laser. RESULTS: All the patients complained of ocular pain between 1 and 3 days after the procedure. A ring stromal infiltrate peripheral to the flap edge with intact epithelium and an intervening clear zone between the peripheral corneal infiltrates and the limbus was observed in 5 eyes without anterior chamber reaction. All cases improved after several days of topical steroid and antibiotic treatment and systemic steroid. Final visual acuity was 20/25 or better in all cases. CONCLUSIONS: The exact mechanism of this complication is still unknown, which can be confused with infectious keratitis. It is important to maintain a high degree of suspicion for infectious keratitis because the management is very different. The potential outcome can be much worse if the keratitis is due to an infectious etiology which can appear after all types of refractive laser procedures. 相似文献
998.
999.
Lifshitz T Levy J Klemperer I Levinger S 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2005,21(5):494-496
PURPOSE: To report a rare case of late bilateral ectasia developing after LASIK for low myopia without preoperative risk factors. METHODS: A 21-year-old man underwent bilateral uneventful LASIK for low myopia of -2.75 diopters in both eyes. Preoperative corneal pachymetry was 531 microm in the right eye and 526 microm in the left eye. The total ablation depth was 46.8 microm in the right eye and 42.2 microm in the left eye. Preoperative corneal topography was normal and did not reveal forme fruste keratoconus. RESULTS: Twenty-four months postoperatively, the patient developed bilateral inferior keratectasia of +0.50 -3.00 x 72 degrees in the right eye and +1.00 -2.75 x 99 degrees in the left eye. CONCLUSIONS: Late keratectasia may follow LASIK for low myopia despite a thorough preoperative work-up. 相似文献
1000.