全文获取类型
收费全文 | 4079篇 |
免费 | 350篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 30篇 |
儿科学 | 98篇 |
妇产科学 | 54篇 |
基础医学 | 531篇 |
口腔科学 | 149篇 |
临床医学 | 396篇 |
内科学 | 783篇 |
皮肤病学 | 104篇 |
神经病学 | 400篇 |
特种医学 | 108篇 |
外科学 | 429篇 |
综合类 | 174篇 |
一般理论 | 1篇 |
预防医学 | 279篇 |
眼科学 | 216篇 |
药学 | 281篇 |
中国医学 | 12篇 |
肿瘤学 | 407篇 |
出版年
2023年 | 32篇 |
2022年 | 74篇 |
2021年 | 133篇 |
2020年 | 86篇 |
2019年 | 115篇 |
2018年 | 169篇 |
2017年 | 115篇 |
2016年 | 113篇 |
2015年 | 119篇 |
2014年 | 162篇 |
2013年 | 201篇 |
2012年 | 284篇 |
2011年 | 319篇 |
2010年 | 171篇 |
2009年 | 130篇 |
2008年 | 213篇 |
2007年 | 233篇 |
2006年 | 198篇 |
2005年 | 166篇 |
2004年 | 195篇 |
2003年 | 154篇 |
2002年 | 120篇 |
2001年 | 84篇 |
2000年 | 73篇 |
1999年 | 74篇 |
1998年 | 34篇 |
1997年 | 25篇 |
1996年 | 21篇 |
1995年 | 26篇 |
1994年 | 22篇 |
1993年 | 18篇 |
1992年 | 50篇 |
1991年 | 39篇 |
1990年 | 38篇 |
1989年 | 35篇 |
1988年 | 41篇 |
1987年 | 36篇 |
1986年 | 34篇 |
1985年 | 28篇 |
1984年 | 32篇 |
1983年 | 29篇 |
1982年 | 19篇 |
1981年 | 16篇 |
1979年 | 31篇 |
1977年 | 10篇 |
1976年 | 12篇 |
1975年 | 13篇 |
1974年 | 11篇 |
1973年 | 10篇 |
1968年 | 10篇 |
排序方式: 共有4452条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
A S Bansal R Chee V Nagendran A Warner G Hayman 《Journal of investigational allergology & clinical immunology》2007,17(3):189-191
Brazil nuts are the second most frequent cause of nut allergy in the United Kingdom. We report the case of a 20-year-old woman with documented Brazil nut allergy who developed widespread urticaria and mild dyspnea after intercourse with her boyfriend who had earlier consumed Brazil nuts. Skin prick testing with the boyfriend's semen after Brazil nut consumption confirmed significant reactivity whereas a sample before nut consumption was negative. We believe this to be the first case of a sexually transmitted allergic reaction. 相似文献
5.
6.
Involvement of platelet activating factor and thromboxane A2 in the renal response to unilateral ureteral obstruction 总被引:1,自引:0,他引:1
Platelet activating factor (PAF) and thromboxane A2 (TxA2) are two vasoactive mediators which can decrease renal blood flow. Both are synthesized by various intrarenal cell types or by macrophages which may infiltrate the kidney during unilateral ureteral obstruction (UUO). In several experimental systems, PAF receptor activation is accompanied by TxA2 release; pharmacological modification of TxA2 synthesis or receptor activation modulates the response to PAF. The involvement of PAF in UUO has not been studied previously, and the role of TxA2 has not been clearly defined by previous investigations. The hemodynamic response to acute UUO is characterized by decreases in renal blood flow (RBF) and glomerular filtration rate and an acute increase in ureteral pressure. In the present experiments, the involvement of either PAF or TxA2 in the acute response to UUO was studied by determining if blockade of either the TxA2 or PAF receptor would affect the renal hemodynamic response to UUO. In addition, the effect of blockade of the TxA2 receptor on the renal response to PAF was determined. Our results indicate that only a small portion of the renal response to PAF is mediated by TxA2, and that neither PAF nor TxA2 can be implicated in the acute hemodynamic response to UUO. TxA2 or PAF involvement in the chronic response to UUO still remains to be determined. 相似文献
7.
Do ethnicity and gender have an impact on pain thresholds in minor dermatologic procedures? 总被引:3,自引:0,他引:3
Gil Yosipovitch Gregory Meredith Yiong Huak Chan Chee Leok Goh 《Skin research and technology》2004,10(1):38-42
Background and Objectives: The perception of pain is a personal experience influenced by many factors, including genetic, ethnic and cultural issues. Understanding these perceptions is especially important in dermatologic patients undergoing minor surgical operations and who often differ in their pain response to surgical treatments. Little is known about how these differences affect the perception of experimental pain. The purpose of this study was to determine experimental pain perception differences in three distinct East Asian ethnic populations.
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献
Methods: Pain thresholds were examined with a psychophysical computerized quantitative thermal sensory testing device (TSA 2001) in healthy volunteers recruited from three different Asian ethnic groups. Using the methods of limits, experimental pain perception threshold was measured on the forehead and volar aspect of the forearm in 49 healthy subjects. The measurements were then repeated after skin barrier perturbation with adhesive tape stripping of the stratum corneum. All three ethnic groups were analyzed separately with respect to age, gender educational level and skin type.
Results: A total of 20 Chinese, 14 Malay and 15 Indian subjects completed the study. Thermal pain thresholds were similar in all three ethnic groups before and after tape strippings. No significant differences were noted between genders.
Conclusions: Using quantitative sensory thermal testing, we demonstrated that no significant differences in pain occur between different races and genders. 相似文献
8.
9.
Alain Deschamps Ian Kaufman Alana Geist Steven S. B. Backman Karen Loo 《Journal canadien d'anesthésie》2007,54(3):183-189
PURPOSE: To evaluate the correlation between the progression of somatosensory blockade and changes in autonomic outflow following the onset of labour epidural analgesia. METHODS: Twelve labouring parturients consented to participate in the study. Baseline electrocardiogram, blood pressure (BP) and respiratory rate were recorded for ten minutes. The epidural consisted of 0.125% bupivacaine with 50 microg of fentanyl (total volume 20 mL). Measurements were repeated for ten minutes after initiation of the block. The level of sensory block was measured bilaterally with loss of sensation to ice at two-minute intervals. Wavelet transform was used to obtain heart rate (HR) and BP variability every two minutes following the loading dose of epidural medication. High frequency power of HR variability was used to assess changes in parasympathetic activity. The total power of BP variability was used to assess changes in sympathetic activity. A nonparametric repeated measures ANOVA was used for the variability data, and a Spearman rank correlation test was used to evaluate the relationship between the sensory block and HR and BP variability. RESULTS: The sensory block progressed to T9 at ten minutes post-epidural and was the mirror image of the decrease in total power of BP variability. High frequency power of HR variability increased to a plateau at six minutes post-epidural. A significant correlation was found between the increase in sensory block and the observed decrease in BP variability (r = -1.000, P = 0.0028). CONCLUSION: In this study of labouring parturients, BP variability correlated with the progression of both sympathetic and somatosensory block following epidural anesthesia, while HR variability was shown to be a surrogate marker of increased parasympathetic activity. 相似文献
10.
B van der Loo E Krieger J Katavic S Spring V Rousson B Amann-Vesti R Koppensteiner 《European journal of vascular and endovascular surgery》2005,30(5):469-474
OBJECTIVE: To determine the relationship between carotid intima-media thickness (IMT), carotid wall shear stress (WSS) and restenosis after femoro-popliteal percutaneous transluminal angioplasty (PTA). PATIENTS AND METHODS: Thirty-one subjects (18 men, 13 women, median age 69 years) treated with femoro-popliteal PTA for symptomatic peripheral arterial occlusive disease were enrolled. On admission, IMT, internal diameter and blood velocity of the common carotid artery (CCA) were assessed by high-resolution ultrasonography. Blood viscosity was measured and carotid WSS was calculated. Patients were followed up for 6 months for the occurrence of significant restenosis (>50%) as documented by duplex ultrasonography. Two patients were lost to follow-up. RESULTS: Fourteen patients (48%) developed restenosis at 6 months. IMT and WSS were not different in patients without and with restenosis (IMT: 0.90 (0.85-0.97) vs. 0.89 (0.84-0.93) mm, p = 0.51; WSS: 14.1 (11.9-19.2) vs. 15.9 (12.8-21.5) dyne/cm2, p = 0.48). The hazard ratio of incident restenosis as estimated by Cox regression analysis was 0.04 for IMT (p = 0.23; 95% CI 0.0001-8.22) and 1.07 for WSS (p = 0.10; 95% CI 0.98-1.17). CONCLUSIONS: In this pilot study involving a limited number of patients, carotid IMT and carotid WSS are not significantly related to restenosis at 6 months after femoro-popliteal PTA. This might be the result of different underlying pathophysiology for atherosclerosis and restenosis. 相似文献