全文获取类型
收费全文 | 1187篇 |
免费 | 61篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 68篇 |
妇产科学 | 8篇 |
基础医学 | 125篇 |
口腔科学 | 21篇 |
临床医学 | 153篇 |
内科学 | 301篇 |
皮肤病学 | 51篇 |
神经病学 | 19篇 |
特种医学 | 298篇 |
外科学 | 80篇 |
综合类 | 23篇 |
预防医学 | 40篇 |
眼科学 | 5篇 |
药学 | 55篇 |
中国医学 | 2篇 |
肿瘤学 | 56篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 9篇 |
2019年 | 8篇 |
2018年 | 19篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 14篇 |
2014年 | 14篇 |
2013年 | 40篇 |
2012年 | 24篇 |
2011年 | 15篇 |
2010年 | 40篇 |
2009年 | 60篇 |
2008年 | 24篇 |
2007年 | 59篇 |
2006年 | 23篇 |
2005年 | 24篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 16篇 |
1999年 | 20篇 |
1998年 | 71篇 |
1997年 | 80篇 |
1996年 | 101篇 |
1995年 | 61篇 |
1994年 | 59篇 |
1993年 | 52篇 |
1992年 | 16篇 |
1991年 | 17篇 |
1990年 | 24篇 |
1989年 | 42篇 |
1988年 | 41篇 |
1987年 | 40篇 |
1986年 | 47篇 |
1985年 | 43篇 |
1984年 | 10篇 |
1983年 | 16篇 |
1982年 | 16篇 |
1981年 | 10篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1978年 | 12篇 |
1977年 | 9篇 |
1976年 | 13篇 |
1975年 | 13篇 |
1973年 | 2篇 |
排序方式: 共有1306条查询结果,搜索用时 15 毫秒
51.
María Belén Acevedo J. Christopher Eagon Bruce D. Bartholow Samuel Klein Kathleen K. Bucholz Marta Yanina Pepino 《Surgery for obesity and related diseases》2018,14(3):277-283
Background
While it is well established that Roux-en-Y gastric bypass (RYGB) causes a rapid and heightened peak blood alcohol concentration (BAC), results from previous studies on the effects of sleeve gastrectomy (SG) on alcohol pharmacokinetics are conflicting. Data from 2 studies found SG did not affect BAC, whereas another study found SG caused a heightened peak BAC after alcohol ingestion. Moreover, these 3 studies estimated BAC from breathalyzers, which might not reliably estimate peak BAC.Objectives
The aims of this study were to evaluate (1) the effect of SG, relative to RYGB and a presurgery group, on alcohol pharmacokinetics and subjective effects, and (2) whether breathalyzers are reliable in this population.Setting
Single-center prospective nonrandomized trial.Methods
We performed alcohol challenge tests in 11 women who had SG surgery 1.9 ± .1 years ago (body mass index = 35.1 ± 6.6 kg/m2), 8 women who had RYGB surgery 2.2 ± .4 years ago (body mass index = 30.0 ± 5.2 kg/m2), and 9 women who were scheduled for bariatric surgery (body mass index = 44.1 ± 4.0 kg/m2). BACs were estimated from breath samples and measured by gas chromatography at various times after consuming approximately 2 standard drinks.Results
BAC increased faster, peak BAC was approximately 2-fold higher, and feelings of drunkenness were heightened in both SG and RYGB groups relative to the presurgery group (P values<.001). BAC estimated from breath samples underestimated BAC by 27% (standard deviation = 13%) and missed peak BACs postsurgery.Conclusions
SG, similar to RYGB, causes marked alterations in the response to alcohol ingestion manifested by a faster and higher peak BAC. The breathalyzer is invalid to assess effects of gastric surgeries on pharmacokinetics of ingested alcohol. 相似文献52.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
53.
Direct sagittal computed tomographic scanning (DSCT) of the shoulder was performed in 42 symptomatic patients, six healthy volunteers, and two cadaver shoulders. Axial CT scanning and double-contrast arthrography with plain radiographs were performed in 41 patients for comparison. DSCT enabled correct identification of 27 of 29 lesions in 24 patients. Seventeen patients had normal shoulders. Axial CT scanning and DSCT together enabled correct identification of all lesions and were markedly superior to plain-film arthrography. DSCT enabled diagnosis of all cases of complete rotator cuff tear plus three cases of incomplete tear and three of rotator cuff atrophy not identified by the other techniques. Axial CT scanning was better than DSCT for diagnosis of Bankart lesions. 相似文献
54.
Urine-compatible polymer for long-term ureteral stenting 总被引:1,自引:0,他引:1
Internal double-J ureteral stents were designed from a urine-compatible polymer (C-Flex), and 35 stents were placed in patients. The overall patency rate for the stents was 80%, with most stent failures occurring before 2 months; the follow-up period ranged from 2 to 16 months, with a mean follow-up for all stents of 5.0 months. Stents were considered patent at last follow-up only if they had been in place for at least 2 months. No migration or fracture of the stents occurred. Physical properties of urine-exposed stents were compared with those of virgin tubing and tubing exposed for 1 year to shelf conditions. Stent patency was optimized by increasing urine flow by increasing the patient's voluntary oral intake, administering prophylactic oral antibiotics, and avoiding placement of stents into grossly bloody or infected collecting systems. 相似文献
55.
Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4 总被引:4,自引:0,他引:4
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci. 相似文献
56.
Immunologic studies performed in a case of autoimmune chronic hemolytic anemia with low titer cold agglutinins (1/16) demonstrated that the cold agglutinins corresponded to monoclonal IgG with anti-Pr specificity. This antibody had a large thermal amplitude, being active at 37 degrees C. These unusual characteristics may define a distinct subset of chronic cold agglutinin disease. 相似文献
57.
Patricia K. Eagon PhD Lynne E. Porter MD Judith S. Gavaler BS Kimberly M. Egler BS David H. Van Thiel MD 《Alcoholism, clinical and experimental research》1981,5(2):183-187
Male, but not female, rat liver cytosol contains an estrogen-binding protein with unique properties: rapid binding of estradiol, high binding capacity, moderate affinity for estradiol, and specificity for steroidal estrogens and weak androgens, but not for nonsteroidal estrogens or other steroids. The estradiol-binding activity of this protein is reduced in cytosol from livers of alcohol-fed rats as compared to that from their isoca-lorically fed controls. The properties of this male-specific hepatic estrogen-binding protein suggest a role for this protein in the regulation of estrogen levels in the male animal. Moreover, the reduction in activity of this unique protein in the liver of alcohol-fed animals may explain, at least in part, the feminization commonly seen in chronic alcoholic men. 相似文献
58.
E Aubeny M Buhler JC Colau E Vicaut M Zadikian M Childs 《The European journal of contraception & reproductive health care》2013,18(4):267-277
Objectives This follow-up study was planned to establish the frequency with which women miss their contraceptive pill, and to observe their behavior when they forget it. In those women who changed from a continuous cycle to an interrupted type of cycle, or vice versa, the study also aimed to evaluate the impact of this change on the pattern of omission of pills. Methods The longitudinal, prospective cohort study included healthy women of child-bearing age for whom a change of pill was being prescribed by their gynecologist. Data were recorded during the 6 months preceding inclusion in the study, and for the 6 months of follow-up; the women were asked to complete a diary in which they recorded the number and exact times of pill omission, and their behavior at each omission. Results A total of 617 gynecologists included 3316 women into the study; of these, a group of 2418 (73%) revisited the same gynecologist at follow-up. The groups who either visited the same or a different gynecologist were similar with respect to age, oral contraception type, omission type and frequency. A large non-compliance rate and women's difficulties in maintaining safe contraception after missing a pill were observed in the group with follow-up. Women were never risk-free when they missed a pill; they turned to numerous sources for discordant or conflicting information; 15% of 'not-forgetting' women at the pre-inclusion cycle recorded at least one omission at the last cycle of the 6-month follow-up period. Omission fluctuations during the observational period make it difficult to designate 'forgetful' or 'non-forgetful' classes of women. Administration of the pill in a continuous cycle, and probably 'study' and 'auto-questionnaire' effects, contributed to an improvement in compliance. In the group taking the continuous cycle pill, the omission number slightly decreased, particularly on the first day and week of the cycle, irrespective of the initial cycle type. Conclusions The importance of the phenomenon of non-compliance rate is confirmed as well as women's difficulties in knowing how to maintain contraceptive safety. The continuous cycle regimen is likely to improve women's compliance during the critical period of the cycle. 相似文献
59.
T2 values in the human brain: comparison with quantitative assays of iron and ferritin 总被引:8,自引:0,他引:8
Chen JC; Hardy PA; Clauberg M; Joshi JG; Parravano J; Deck JH; Henkelman RM; Becker LE; Kucharczyk W 《Radiology》1989,173(2):521-526
Magnetic resonance (MR) imaging with a whole-body imager was performed in 10 fresh, unfixed whole human brains selected randomly from cadavers. All subjects were neurologically intact before death. T2 time constants were measured within the caudate nucleus, putamen, globus pallidus, cortical gray matter, subcortical white matter, and optic radiation. These regions were then excised, and T2 values were measured again with a 1.5-T MR spectrometer. Quantitative assays of iron, ferritin, and protein from these areas were then performed. Iron concentration varied significantly among brain regions, whereas ferritin and protein concentrations were constant among brain regions and among individuals. Neither iron nor ferritin concentration showed any consistent correlation with T2 values. Histologic examination of brain micro-sections with iron- and ferritin-specific stains of demonstrated poor correlation with biochemical assays of ferritin and iron concentrations. Results indicate that T2 values correlate poorly with iron and ferritin concentrations found in neurologically intact brains. 相似文献
60.
Eric D. Jenkins Victoria Yom Lora Melman L. Michael Brunt J. Christopher Eagon Margaret M. Frisella Brent D. Matthews 《Surgical endoscopy》2010,24(12):3002-3007