全文获取类型
收费全文 | 331篇 |
免费 | 21篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 32篇 |
妇产科学 | 8篇 |
基础医学 | 35篇 |
口腔科学 | 11篇 |
临床医学 | 25篇 |
内科学 | 70篇 |
皮肤病学 | 7篇 |
神经病学 | 7篇 |
特种医学 | 60篇 |
外科学 | 21篇 |
综合类 | 8篇 |
预防医学 | 8篇 |
眼科学 | 3篇 |
药学 | 19篇 |
中国医学 | 6篇 |
肿瘤学 | 39篇 |
出版年
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 4篇 |
2016年 | 2篇 |
2015年 | 8篇 |
2014年 | 6篇 |
2013年 | 12篇 |
2012年 | 12篇 |
2011年 | 8篇 |
2010年 | 19篇 |
2009年 | 18篇 |
2008年 | 11篇 |
2007年 | 6篇 |
2006年 | 9篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 11篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 7篇 |
1999年 | 11篇 |
1998年 | 21篇 |
1997年 | 18篇 |
1996年 | 20篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 6篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 11篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 1篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1975年 | 1篇 |
1948年 | 2篇 |
1932年 | 1篇 |
1925年 | 1篇 |
1924年 | 1篇 |
排序方式: 共有360条查询结果,搜索用时 0 毫秒
1.
Complications from improperly placed biliary stents are not uncommon. Free loose wires from the ends of an uncovered stent can irritate and damage adjacent mucosal surfaces. Effective management can be achieved via percutaneous placement of a second stent to alter the orientation of the original stent. 相似文献
2.
3.
Ishiguro A; Spirin KS; Shiohara M; Tobler A; Gombart AF; Israel MA; Norton JD; Koeffler HP 《Blood》1996,87(12):5225-5231
4.
Mandy B Belfort John AF Zupancic Katherine M Riera Jane HG Turner Lisa A Prosser 《BMC pediatrics》2011,11(1):12
Background
Childhood obesity is a substantial public health problem. The extent to which health state preferences (utilities) are related to a child's weight status has not been reported. The aims of this study were (1) to use a generic health state classification system to measure health related quality of life and calculate health utilities in a convenience sample of children and adolescents and (2) to determine the extent to which these measures are associated with weight status and body mass index (BMI). 相似文献5.
Genital asymmetry in men 总被引:1,自引:0,他引:1
This study examined genital asymmetry in a large sample of men. The
probands were 6544 non-delinquent men who were interviewed by the Kinsey
Institute for Research in Sex, Gender and Reproduction from 1938 to 1963.
The measures were four indicators of penile and scrotal asymmetry, along
with self-reported handedness, from Kinsey's interview protocol. Most men
reported some degree of lateral asymmetry in their flaccid penis and in
their testicles; less asymmetry was reported for their erect penis. The
asymmetry typically occurred in the left direction, and this pattern
occurred in both right- and nonright- handers. However, this 'leftward'
pattern was significantly less pronounced in nonright-handers. The results
are discussed in relation to previous findings of genital asymmetry in men,
the possible relationship of genital asymmetry to functional cerebral
asymmetry, and recent data suggesting genital asymmetry may predict
patterns of cognitive performance and genital/sexual organ cancers.
相似文献
6.
Objectives
To analyze the concept of “case series” in the medical literature compared with case reports.Methods
A PubMed search for articles published during 2009 which had “case series” in their title was performed. A total number of 621 articles were retrieved. 586 papers were included in the analysis and 35 were excluded (18 were commentary letters, 5 were not in English, and twelve could not be retrieved by our Library). The number of patients and category of these articles were analyzed.Results
The median (range) of the number of cases of articles having “case series” in their title was 7 (1–6432) cases. 186/ 586 articles had less than 5 cases (31.7%, 95% CI (28.3–35.1%)). The median (range) of the number of cases of articles having “case report” as their publication type was 4 (1–178) cases. Out of the 219 articles categorized as case reports 114 (52.1%, 95% CI (45.6–58.6%)) had less than five cases.Conclusions
The concept of “case series” is not well defined in the literature and does not reflect a specific research design. We suggest that a case series should have more than four patients while four paitents or less should be reported individually as case reports. 相似文献7.
In hypertension, an increase in arterial wall thickness and loss of elasticity over time result in an increase in pulse wave velocity, a direct measure of arterial stiffness. This change is reflected in gradual fragmentation and loss of elastin fibers and accumulation of stiffer collagen fibers in the media that occurs independently of atherosclerosis. Similar results are seen with an elevated level of homocysteine (Hcy), known as hyperhomocysteinemia (HHcy), which increases vascular thickness, elastin fragmentation, and arterial blood pressure. Studies from our laboratory have demonstrated a decrease in elasticity and an increase in pulse wave velocity in HHcy cystathionine β synthase heterozygote knockout (CBS(-/+)) mice. Nitric oxide (NO) is a potential regulator of matrix metalloproteinase (MMP) activity in MMP-NO-TIMP (tissue inhibitor of metalloproteinase) inhibitory tertiary complex. We have demonstrated the contribution of the NO synthase (NOS) isoforms, endothelial NOS and inducible NOS, in the activation of latent MMP. The differential production of NO contributes to oxidative stress and increased oxidative/nitrative activation of MMP resulting in vascular remodeling in response to HHcy. The contribution of the NOS isoforms, endothelial and inducible in the collagen/elastin switch, has been demonstrated. We have showed that an increase in inducible NOS activity is a key contributor to HHcy-mediated collagen/elastin switch and resulting decline in aortic compliance. In addition, increased levels of Hcy compete and suppress the γ-amino butyric acid-receptor, N-methyl-d-aspartame-receptor, and peroxisome proliferator-activated receptor. The HHcy causes oxidative stress by generating nitrotyrosine, activating the latent MMPs and decreasing the endothelial NO concentration. The HHcy causes elastinolysis and decrease elastic complicance of the vessel wall. The treatment with γ-amino butyric acid-receptor agonist (muscimol), N-methyl-d-aspartame-receptor agonist (MK-801), and peroxisome proliferator-activated receptor agonists (ciprofibrate and ciglitazone) mitigates the cardiovascular dysfunction in HHcy. 相似文献
8.
Background
Critically-ill trauma patients have a high mortality.Objective
To study the factors affecting the mortality of ICU trauma patients treated at Al-Ain Hospital, United Arab Emirates (UAE).Methods
All trauma patients who were admitted to the ICU were prospectively collected over three years (2003–2006). Univariate and multivariate analysis were used to compare patients who died and who did not. Gender, age, nationality, mechanism of injury, systolic blood pressure and GCS on arrival, the need for ventilation, presence of head or chest injuries, AIS for the chest and head injuries and the ISS were studied.Results
There were 202 patients (181 males). The most common mechanism of injury was road traffic collisions (72.3 %). The overall mortality was 13.9%. A direct logistic regression model has shown that factors that affected mortality were decreased GCS (p < 0.0001), mechanism of injury (p = 0.004) with burns having the highest mortality, increased age (p = 0.004), and increased ISS (p = 0.02). The best GCS that predicted mortality was 5.5 while the best ISS that predicted mortality was 13.5.Conclusion
Road traffic collision is the most common cause of serious trauma in UAE followed by falls. Decreased GCS was the most significant factor that predicted mortality in the ICU trauma patients. 相似文献9.
Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control. 相似文献
10.
Monocyte-mediated antibody-dependent cell-mediated cytotoxicity: the role of the metabolic burst 总被引:4,自引:0,他引:4
Human monocytes respond to opsonized microorganisms with a "metabolic burst" composed of an increase in oxygen consumption, an increase in hexose monophosphate shunt (HMPS) activity, and the generation of reactive oxygen species (ROS). We investigated the role of the metabolic burst in antibody-dependent cell-mediated cytotoxicity (ADCC) by human monocytes toward anti-D coated erythrocyte target cells because recent studies suggested a role for oxygen-dependent bactericidal mechanisms in ADCC. In normal monocytes, we found that ADCC was nearly halved under hypoxic conditions. Several agents known to impair activation of the burst, such as vincristine, cation chelators, and a sulfhydryl reagent, all decreased cytotoxicity if added before initiation of contact between target and effector cells. Cytotoxicity was inhibited by 2-deoxyglucose but not fluoride, suggesting a nonglycolytic role for glucose in ADCC, perhaps in the HMPS pathway. Although these data suggested a role for the metabolic burst in ADCC, scavengers of ROS did not impair cytotoxicity, and monocytes from chronic granulomatous disease (CGD) patients who had a defective metabolic burst had normal levels of ADCC. We conclude that ADCC toward anti-D coated erythrocyte target cells was the result of at least two independent but closely related cytotoxic pathways. Although one of these pathways appeared to involve the metabolic burst, the potentially cytotoxic reactive oxygen species did not appear to play a role in this system. 相似文献