全文获取类型
收费全文 | 468篇 |
免费 | 42篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 16篇 |
妇产科学 | 14篇 |
基础医学 | 37篇 |
口腔科学 | 2篇 |
临床医学 | 50篇 |
内科学 | 138篇 |
皮肤病学 | 4篇 |
神经病学 | 46篇 |
特种医学 | 68篇 |
外科学 | 33篇 |
综合类 | 19篇 |
预防医学 | 35篇 |
眼科学 | 4篇 |
药学 | 24篇 |
中国医学 | 1篇 |
肿瘤学 | 26篇 |
出版年
2021年 | 6篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 11篇 |
2017年 | 8篇 |
2016年 | 7篇 |
2015年 | 12篇 |
2014年 | 16篇 |
2013年 | 20篇 |
2012年 | 28篇 |
2011年 | 16篇 |
2010年 | 14篇 |
2009年 | 18篇 |
2008年 | 7篇 |
2007年 | 24篇 |
2006年 | 15篇 |
2005年 | 13篇 |
2004年 | 4篇 |
2003年 | 16篇 |
2002年 | 10篇 |
2001年 | 13篇 |
2000年 | 9篇 |
1999年 | 11篇 |
1998年 | 17篇 |
1997年 | 16篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 10篇 |
1986年 | 10篇 |
1985年 | 11篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 15篇 |
1979年 | 5篇 |
1978年 | 9篇 |
1977年 | 4篇 |
1976年 | 9篇 |
1975年 | 9篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有518条查询结果,搜索用时 15 毫秒
91.
The concentrations of norepinephrine, dopamine-beta-hydroxylase, dopamine, tyrosine hydroxylase, phenylethanolamine-N-methyltransferase, serotonin, tryptophan hydroxylase, histamine, glutamic acid decarboxylase, and choline acetyltransferase were determined in selected hypothalamic nuclei and in the median eminence after deafferentation of the medial basal hypothalamus. Norepinephrine and dopamine-beta-hydroxylase fell markedly while dopamine and tyrosine hydroxylase did not. Serotonin also decreased in all regions studied; histamine decreased in none. Choline acetyltransferase, phenylethanolamine-N-methyltransferase, and glutamic acid decarboxylase declined in some areas, but not in others. 相似文献
92.
93.
L R Goldman D F Smith R R Neutra L D Saunders E M Pond J Stratton K Waller R J Jackson K W Kizer 《Archives of environmental health》1990,45(4):229-236
Aldicarb, a carbamate pesticide, is the most potent pesticide in the market and has a LD50 of 1 mg/kg. In the United States it is illegal to use aldicarb on certain crops, e.g., watermelons, because it is incorporated into the flesh of the fruit. Once an accidental or illegal use of such a potent pesticide occurs, there is no easy way for the agricultural or public health system to protect the populace. This paper describes the impact of one such event upon the health of individuals and the institutions of California. On July 4, 1985, California and other western states experienced the largest known outbreak of food-borne pesticide illness ever to occur in North America. This was attributed to watermelons contaminated through the illegal or accidental use of aldicarb by a few farmers in one part of the state. Within California, a total of 1,376 illnesses resulting from consumption of watermelons was reported to the California Department of Health Services (CDHS). Of the 1,376 illnesses, 77% were classified as being probable or possible carbamate illnesses. Many of the case reports involved multiple illnesses associated with the same melon among unrelated individuals. Seventeen individuals required hospitalization. There were 47 reports of illness involving pregnant women, two of whom reported having subsequent stillbirths. Thirty-five of the remaining pregnant women were followed-up 9 mo after the epidemic; no additional stillbirths were found.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
94.
Pseudoaneurysm is a well-documented but rare complication of retrograde femoral arterial puncture. We present six patients in whom pseudoaneurysm complicated this procedure. The pseudoaneurysm arose from the superficial femoral artery in five patients and from the profunda femoris artery in one. An arteriovenous fistula also arose from the superficial femoral artery in one patient. In no patient did the pseudoaneurysm arise from the common femoral artery. Two mechanisms are postulated as to why pseudoaneurysms rarely complicate puncture of the common femoral artery. 相似文献
95.
Kizer JR Arnett DK Bella JN Paranicas M Rao DC Province MA Oberman A Kitzman DW Hopkins PN Liu JE Devereux RB 《Hypertension》2004,43(6):1182-1188
The degree to which ethnic differences in left ventricular structure among hypertensive adults are independent of clinical and hemodynamic factors remains uncertain. We assessed whether left ventricular mass and geometry differ between black and white hypertensives after accounting for differences in such factors. Our study group comprised 1060 black and 580 white hypertensive participants free of valvular or coronary disease in a population-based cohort. Blood pressure was measured during a clinic visit and echocardiography was performed using standardized protocols. After controlling for clinical and hemodynamic parameters (cardiac index, peripheral resistance index, and pulse pressure/stroke index), both left ventricular mass and relative wall thickness were higher in blacks than whites (173.9+/-30.9 versus 168.3+/-24.3 grams, P=0.006, and 0.355+/-0.055 versus 0.340+/-0.055 grams, P<0.001). Similarly, the adjusted risk of having left ventricular hypertrophy, whether indexed by height(2.7) or by body surface area, was greater for blacks than for whites (odds ratio: 1.80; 95% CI: 1.29 to 2.51; and odds ratio: 2.50; 95% CI: 1.58 to 3.96, respectively), and this was also true for concentric geometry (odds ratio: 2.28; 95% CI: 1.22 to 4.25). Further adjustment for relatedness in this genetic epidemiological study did not attenuate these differences. Our findings confirm the strong association between black ethnicity and increased left ventricular mass and relative wall thickness in hypertensive adults and demonstrate that these differences are independent of standard clinical and hemodynamic parameters. Whether such differences relate to distinct ambulatory pressure profiles or an ethnic propensity to cardiac hypertrophy requires further investigation. 相似文献
96.
Persistent mullerian duct syndrome is a rare disease that occurs in men with a completely normal phenotype and is characterized by the presence of mullerian duct structures. Diagnostic laparoscopy can reveal an appearance consistent with a uterus, fallopian tubes, or ovotestes. 相似文献
97.
98.
Philip Bao Douglas Potter David P Eisenberg Diana Lenzner Herbert J Zeh Kenneth KW Lee III Steven J Hughes Michael K Sanders Jennifer L Young A James Moser 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2009,11(7):606-611
Background:
The surgeon''s contribution to patients with localized pancreatic adenocarcinoma (PAC) is a margin negative (R0) resection. We hypothesized that a prediction rule based on pre-operative imaging would maximize the R0 resection rate while reducing non-therapeutic intervention.Methods:
The prediction rule was developed using computed tomography (CT) and endoscopic ultrasound (EUS) data from 65 patients with biopsy-proven PAC who underwent attempted resection. The rule classified patients as low or high risk for non-R0 outcome and was validated in 78 subsequent patients.Results:
Model variables were: any evidence of vascular involvement on CT; EUS stage and EUS size dichotomized at 2.6 cm. In the validation cohort, 77% underwent resection and 58% achieved R0 status. If only patients in the low-risk group underwent surgery, the prediction rule would have increased the resection rate to 92% and the R0 rate to 73%. The R0 rate was 40% higher in low-risk compared with high-risk patients (P < 0.001). High risk was associated with a 67% rate of non-curative surgery (unresectable disease and metastases).Conclusion:
The prediction rule identified patients most likely to benefit from resection for PAC using pre-operative CT and EUS findings. Model predictions would have increased the R0 rate and reduced non-therapeutic interventions. 相似文献99.