全文获取类型
收费全文 | 1758篇 |
免费 | 93篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 90篇 |
妇产科学 | 94篇 |
基础医学 | 135篇 |
口腔科学 | 69篇 |
临床医学 | 192篇 |
内科学 | 417篇 |
皮肤病学 | 47篇 |
神经病学 | 85篇 |
特种医学 | 66篇 |
外科学 | 390篇 |
综合类 | 25篇 |
预防医学 | 36篇 |
眼科学 | 33篇 |
药学 | 65篇 |
中国医学 | 2篇 |
肿瘤学 | 78篇 |
出版年
2024年 | 3篇 |
2023年 | 23篇 |
2022年 | 12篇 |
2021年 | 48篇 |
2020年 | 27篇 |
2019年 | 29篇 |
2018年 | 51篇 |
2017年 | 43篇 |
2016年 | 58篇 |
2015年 | 68篇 |
2014年 | 79篇 |
2013年 | 103篇 |
2012年 | 129篇 |
2011年 | 130篇 |
2010年 | 66篇 |
2009年 | 43篇 |
2008年 | 104篇 |
2007年 | 115篇 |
2006年 | 139篇 |
2005年 | 110篇 |
2004年 | 99篇 |
2003年 | 69篇 |
2002年 | 80篇 |
2001年 | 52篇 |
2000年 | 37篇 |
1999年 | 28篇 |
1998年 | 13篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1992年 | 4篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 9篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1975年 | 2篇 |
1974年 | 5篇 |
1972年 | 5篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1968年 | 3篇 |
1967年 | 3篇 |
1965年 | 3篇 |
排序方式: 共有1870条查询结果,搜索用时 15 毫秒
1.
2.
OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability. 相似文献
3.
The influence of different levels of dietary fat on the incidence and growth of MNU-induced mammary carcinoma in rats 总被引:1,自引:0,他引:1
This study describes the influence of isocalorically fed diets (containing different amounts of fat) on tumor incidence and parameters of fat metabolism in female Sprague-Dawley rats. Comparisons are made between rats induced with methylnitrosourea (25 mg/kg body wt) and untreated controls (Group I). The animals received either control diets (3.9% fat by weight, Groups I and II) or fat-enriched diets (10.7%, Group III; 15.6%, Group IV; 21.4%, Group V) over a period of 180 days. At the termination of the experiment, intake of the diet containing 10.7% fat by weight (24% fat per total calories) was associated with the highest tumor incidence. Comparing the different diets, liver lipid concentrations in the individual groups increased with increasing dietary fat, whereas the total lipid in plasma decreased. During the feeding period, total lipid of the liver and plasma, and plasma cholesterol, increased in all groups, but triglycerides of plasma decreased. However, when plasma cholesterol and triglycerides were calculated as a relative amount of total lipid in plasma, cholesterol was found to be significantly decreased in Groups III and IV, and triglycerides were increased in Group III but decreased significantly in Groups I, II, and V at the end of the experiment. 相似文献
4.
Mediation of bradykinin-induced contraction in canine veins via thromboxane/prostaglandin endoperoxide receptor activation 下载免费PDF全文
M O Aksoy C Harakal J B Smith G J Stewart C R Zerweck 《British journal of pharmacology》1990,99(3):461-466
1. Canine jugular and femoral veins were studied to determine the possible importance of thromboxane (TXA2) and prostaglandin endoperoxides (prostaglandin H2, PGH2) in mediating bradykinin(BK)-induced contraction. 2. Isolated vein rings incubated in modified Krebs solution contracted to TXA2/PGH2 analogs SQ26655 and U44069 with potency of contraction exceeding that for BK. The potency ranking for both veins was SQ26655 greater than U44069 greater than BK greater than PGF2 alpha greater than TXB2 much greater than PGD2. 3. The cyclo-oxygenase inhibitors indomethacin (3 x 10(-7) M) and flufenamic acid (10(-5) M) reduced BK contractions without affecting those induced by noradrenaline (NA). 4. TXA2/PGH2 receptor antagonists SQ29548 (10(-8) M) and BM13177 (10(-6) M) strongly inhibited BK-induced tension. The action of antagonists was reversible with negligible influence on NA-elicited contraction. Selective removal of endothelium had no effect on BK-induced contraction or the action of the antagonists. 5. The thromboxane synthase inhibitors dazoxiben (10(-4) M) and CGS 12970 (10(-5) M) had no significant inhibitory effect on BK-induced tension. 6. These results suggest that in canine jugular and femoral vein, the action of BK is largely dependent upon stimulation of the cyclo-oxygenase pathway to produce PGH2 and possibly TXA2, which can activate a smooth muscle TXA2/PGH2 receptor to elicit vasoconstriction. 相似文献
5.
OBJECTIVE: Hyperventilation and ischaemia increase axonal excitability by changing Na+ conductance in healthy subjects. However, the changes in excitability during and after ischaemia in diabetic patients are less than in healthy controls. This is known as ischaemic resistance. In this study, we investigated the effects of hyperventilation for 20 min on strength-duration time constant (SDTC) of motor axons of the median nerve of diabetic patients with polyneuropathy to determine whether diabetics are less affected by hyperventilation, a form of resistance similar to the ischaemic resistance of diabetics. METHODS: The SDTC of 14 diabetic patients with polyneuropathy and 10 healthy volunteers were measured following stimulation of right median nerve at the wrist prior to and after hyperventilation for 20 min. RESULTS: There was a significant increase in the SDTC in control subjects, but no significant change in the SDTC for patients with diabetic polyneuropathy. The score of the clinical response (paraesthesiae and carpopedal spasm) to hyperventilation of controls was also significantly greater in the controls than the patients. CONCLUSION: Hyperventilation for 20 min has little influence on SDTC in patients with diabetic polyneuropathy. SIGNIFICANCE: The 'resistance' of diabetic nerve is not confined to ischaemia but involves other manoeuvres that can alter axonal excitability. 相似文献
6.
7.
8.
Uur Koçer MD Nilgün Atakan MD Hasan Mete Aksoy MD Yigit Özer Tiftikcioglu MD Berna Aksoy MD Müzeyyen Astarci MD 《Dermatologic surgery》2003,29(3):291-293
BACKGROUND: Superficial lymphatic malformations are predominantly developmental malformations of infancy, but they may arise at any age. OBJECTIVE: To describe a patient with a late-onset superficial lymphatic malformation. METHODS: Case report and literature review. RESULTS: A 53-year-old woman was evaluated for a colored lesion that developed spontaneously on the anterior abdominal wall. The lesion was treated by surgical excision. Findings on histopathologic examination of the specimen were consistent with superficial lymphatic malformation. There was no recurrence of the lesion at 4 months after the operation. CONCLUSION: Superficial lymphatic malformations can develop in adults spontaneously without the presence of any predisposing condition. Because the majority of such late-onset malformations reported in the literature are localized lesions similar to the one in our patient, surgical removal with inclusion of subcutaneous tissue usually results in cure without recurrence. 相似文献
9.
Intravenous Pyogenic Granuloma of the Hand 总被引:1,自引:0,他引:1
Ugur Kocer MD Hasan Mete Aksoy MD Yigit Özer Tiftikcioglu MD Önder Karaaslan MD 《Dermatologic surgery》2003,29(9):974-976
BACKGROUND: Intravenous pyogenic granuloma is the intravasal counterpart of cutaneous pyogenic granuloma. This rare, benign lesion appears clinically as a subcutaneous nodule usually located in the upper extremity or neck in middle-aged people. It is hard to make an exact diagnosis on clinical basis, and there is a risk of recurrence because of undertreatment. OBJECTIVE: To report a case of an intravenous pyogenic granuloma located in the hand and to describe the clinical and histopathologic features of this rare vascular tumor. METHODS: An operation was performed on a 58-year-old female who presented with a small, painless mass in the right palm, and the pathologic examination revealed an intravenous pyogenic granuloma. CONCLUSION: This rare lesion should be differentiated from a regular pyogenic granuloma and should be excised with the vein segment to avoid recurrence. 相似文献
10.
Iatrogenic injuries to ureter, bladder and urethra during abdominal and pelvic operations 总被引:1,自引:0,他引:1
Ö Polat O. Gül Y. Aksoy I. Özbey A. Demirel Y. Bayraktar 《International urology and nephrology》1997,29(1):13-18
Abdominal and pelvic operations at Departments of Obstetrics and Gynaecology, and General Surgery play an important role in
ureteral, bladder and rarely urethral injuries.
Fifty-nine patients with iatrogenic ureteral, bladder and urethral injuries were treated at the Department of Urology, Atatürk
University Research Hospital, between 1985 and 1995. These injuries were urinary vaginal fistulas in 43 patients (vesicovaginal
33, ureterovaginal 7, urethrovaginal 2 and vesicovaginal plus urethrovaginal 1), ureteric ligation in 9, bladder laceration
in 7. These injuries were treated by different methods. All patients were followed up by intravenous urography (IVU) and urine
culture three months later.
It must be borne in mind that iatrogenic urinary tract injuries are not rare. Bladder and ureteral catheterization must be
performed to prevent these complications. 相似文献