全文获取类型
收费全文 | 1274篇 |
免费 | 78篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 93篇 |
妇产科学 | 13篇 |
基础医学 | 110篇 |
口腔科学 | 32篇 |
临床医学 | 91篇 |
内科学 | 237篇 |
皮肤病学 | 30篇 |
神经病学 | 48篇 |
特种医学 | 138篇 |
外科学 | 160篇 |
综合类 | 137篇 |
预防医学 | 99篇 |
眼科学 | 4篇 |
药学 | 59篇 |
中国医学 | 39篇 |
肿瘤学 | 77篇 |
出版年
2023年 | 8篇 |
2022年 | 14篇 |
2021年 | 33篇 |
2020年 | 23篇 |
2019年 | 16篇 |
2018年 | 32篇 |
2017年 | 17篇 |
2016年 | 25篇 |
2015年 | 35篇 |
2014年 | 45篇 |
2013年 | 42篇 |
2012年 | 62篇 |
2011年 | 60篇 |
2010年 | 83篇 |
2009年 | 69篇 |
2008年 | 40篇 |
2007年 | 46篇 |
2006年 | 53篇 |
2005年 | 36篇 |
2004年 | 40篇 |
2003年 | 32篇 |
2002年 | 18篇 |
2001年 | 18篇 |
2000年 | 19篇 |
1999年 | 27篇 |
1998年 | 45篇 |
1997年 | 59篇 |
1996年 | 52篇 |
1995年 | 40篇 |
1994年 | 35篇 |
1993年 | 32篇 |
1992年 | 11篇 |
1991年 | 10篇 |
1990年 | 18篇 |
1989年 | 28篇 |
1988年 | 20篇 |
1987年 | 18篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 10篇 |
1983年 | 3篇 |
1982年 | 9篇 |
1981年 | 9篇 |
1980年 | 12篇 |
1979年 | 3篇 |
1977年 | 7篇 |
1976年 | 6篇 |
1971年 | 3篇 |
1958年 | 4篇 |
1957年 | 2篇 |
排序方式: 共有1371条查询结果,搜索用时 15 毫秒
1.
舌黏膜尿道成形治疗尿道狭窄的初步报告 总被引:3,自引:0,他引:3
目的:探讨舌黏膜补片法尿道成形治疗尿道狭窄的疗效。方法:采用舌黏膜尿道成形治疗尿道狭窄14例。尿道狭窄段3.5~14cm,平均6.2cm;术前耻骨上膀胱造瘘8例,余6例排尿均较为困难,最大尿流率2.5~5.5ml/s,平均3.8ml/s。结果:术后随访2~8个月,1例因伤口感染致尿道皮肤瘘,余患者均排尿通畅,最大尿流率增至22~51ml/s,平均29.6ml/s。结论:舌黏膜具有取材方便、对患者创伤小、抗感染力强等特点,是一种较好的尿道替代物,尤其适合尿道狭窄段<6cm的患者。 相似文献
2.
Benjamin Clapp Melba Jarmillo Valeria Vigil Luis Macias Marcia Bouton Cuatemoc Gallardo Andrew Kassir 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):242-245
BACKGROUND AND OBJECTIVES: The purpose of this study was to determine patient recall and comprehension after laparoscopic appendectomy in an underserved population. Laparoscopic surgery can lead to diagnostic uncertainty secondary to poor recall and variable port placement. METHODS: After institutional review board approval, we identified a cohort of patients who underwent laparoscopic appendectomy from 2000 to 2004 at a single institution. We then attempted to contact the patients to conduct a 10-question telephone survey, which determined whether the patient spoke English or Spanish as a primary language, ethnicity, educational level, and questions about recall of perioperative events and diagnoses. If we could not reach the patient, we tried to call back on 2 different occasions. RESULTS: Between 2000 and 2004, 186 patients underwent laparoscopic appendectomy. Of these, 65% were Hispanic. We found that only 17% of these patients returned for a postoperative visit. Only 19.3% could be contacted by phone. Forty-seven percent of the patients contacted by phone spoke Spanish exclusively. Overall 92% of patients contacted knew what operation they had, and gave their correct diagnosis. CONCLUSIONS: The low percentage of patients available to follow-up makes this study statistically insignificant. However, we believe that fact in itself is important. In Southwestern states, we see a large migrant population. This highlights the need to communicate effectively with the patients at the time of surgery, which we speculate we did based on the percentage of patients that knew their diagnosis. 相似文献
3.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
4.
5.
6.
Katherine Patterson Corinna Young Steven Paul Woods Ofilio Vigil Igor Grant J. Hampton Atkinson 《International journal of methods in psychiatric research》2006,15(2):75-82
Major Depressive Disorder (MDD) is among the most prevalent but underdiagnosed psychiatric disorders in persons with HIV infection. Given the known adverse impact of comorbid MDD on HIV disease progression and health‐related quality of life, it is important both for research and for efficient, effective clinical care, to validate existing screening measures that may discriminate between MDD and the somatic symptoms of HIV (such as fatigue). In the current study, we evaluated the concurrent predictive validity of the Profile of Mood States (POMS) Depression‐Dejection scale in detecting current MDD in 310 persons with HIV infection. The Structured Clinical Interview for DSM‐IV (SCID) diagnosis of MDD and the Cognitive‐Affective scale from the Beck Depression Inventory (BDI‐CA) served as comparative diagnostic and severity measures of depression, respectively. Results demonstrated that the POMS Depression‐Dejection scale accurately classified persons with and without MDD SCID diagnoses, with an overall hit rate of 80%, sensitivity of 55%, specificity of 84%, and negative predictive power of 91% using a recommended cutpoint of 1.5 standard deviations above the normative mean. Moreover, the POMS performed comparably to the BDI‐CA in classifying MDD. Findings support the predictive validity of the POMS Depression‐Dejection scale as a screening instrument for MDD in persons with HIV disease. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
7.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
8.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
9.
10.
本文详细介绍了在新疆发现的花蠕形蚤、叶氏蠕形蚤、北山羊蠕形蚤、羊长喙蚤和狍长喙蚤的形态学特点、地理分布和某些生物学特性。 相似文献