全文获取类型
收费全文 | 2226039篇 |
免费 | 158810篇 |
国内免费 | 5349篇 |
专业分类
耳鼻咽喉 | 30008篇 |
儿科学 | 72473篇 |
妇产科学 | 60300篇 |
基础医学 | 322290篇 |
口腔科学 | 61654篇 |
临床医学 | 207928篇 |
内科学 | 424144篇 |
皮肤病学 | 47235篇 |
神经病学 | 178566篇 |
特种医学 | 84361篇 |
外国民族医学 | 563篇 |
外科学 | 321860篇 |
综合类 | 47122篇 |
现状与发展 | 2篇 |
一般理论 | 697篇 |
预防医学 | 175713篇 |
眼科学 | 50255篇 |
药学 | 170707篇 |
12篇 | |
中国医学 | 5527篇 |
肿瘤学 | 128781篇 |
出版年
2019年 | 17642篇 |
2018年 | 25145篇 |
2017年 | 19304篇 |
2016年 | 21299篇 |
2015年 | 24015篇 |
2014年 | 33094篇 |
2013年 | 50048篇 |
2012年 | 68678篇 |
2011年 | 72878篇 |
2010年 | 42647篇 |
2009年 | 39487篇 |
2008年 | 67077篇 |
2007年 | 71484篇 |
2006年 | 71959篇 |
2005年 | 69003篇 |
2004年 | 65936篇 |
2003年 | 63132篇 |
2002年 | 61087篇 |
2001年 | 108716篇 |
2000年 | 111717篇 |
1999年 | 93563篇 |
1998年 | 25129篇 |
1997年 | 22417篇 |
1996年 | 22133篇 |
1995年 | 20959篇 |
1994年 | 19391篇 |
1993年 | 18191篇 |
1992年 | 72527篇 |
1991年 | 70449篇 |
1990年 | 68836篇 |
1989年 | 65675篇 |
1988年 | 60205篇 |
1987年 | 58905篇 |
1986年 | 55799篇 |
1985年 | 52904篇 |
1984年 | 39118篇 |
1983年 | 33199篇 |
1982年 | 19184篇 |
1979年 | 35404篇 |
1978年 | 24563篇 |
1977年 | 20934篇 |
1976年 | 19478篇 |
1975年 | 20878篇 |
1974年 | 25001篇 |
1973年 | 24392篇 |
1972年 | 22804篇 |
1971年 | 21314篇 |
1970年 | 19711篇 |
1969年 | 18443篇 |
1968年 | 17100篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
A L Dannenberg T R Coté M J Kresnow J J Sacks C M Lipsitz E R Schmidt 《Public health reports (Washington, D.C. : 1974)》1993,108(2):212-217
Most of the nearly 1,000 fatal bicycle-related injuries annually could be prevented if riders used safety helmets. Helmet use by adult bicyclists has received relatively little attention because educational campaigns to promote helmet use generally focus on children. Helmet use by adult and child bicyclists at 120 suburban and rural sites in three Maryland counties was observed on two Saturdays in 1990-91 during an evaluation of the impact of a mandatory helmet law. Concordance or discordance of helmet use within various groups of bicyclists--adults only, adults with children, and children only--was recorded. Helmet use among 2,068 adult bicyclists was 49 percent, 51 percent, and 74 percent in the three counties. In two counties combined, 52 percent (365 of 706) of solo adult bicyclists wore helmets compared with only 5 percent (5 of 94) of solo child bicyclists (P < .001). Helmet use or nonuse was concordant among 87 percent of 277 adult-adult pairs, 94 percent of 50 child-child pairs, and 91 percent of 32 adult-child pairs of bicyclists observed. Concordance rates of helmet use or nonuse were similarly high among pairs of adult bicyclists of the same or mixed sexes. These data are consistent with the concept that both adults and children tend to adopt the helmet-wearing behaviors of their companions. Public health efforts focused on adults should encourage helmet use by adult bicyclists both to prevent head injuries and to provide a role model for children. 相似文献
972.
What is the value of bcl-2 protein detection for histopathologists? 总被引:15,自引:0,他引:15
973.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
974.
A case of gasless laparoscopic esophagogastric myotomy for achalasia is presented. The technical aspects of the technique as well as the benefits of this approach are reviewed. 相似文献
975.
976.
977.
Our study was intended to determine whether power Doppler sonography can be considered superior to color Doppler technique in depiction of normal orbital vasculature. Ten healthy volunteers (20 eyes) were examined with a 10 MHz linear probe; each orbital vessel was recorded with both color and power Doppler methods; the images were reviewed independently by all the observers, who agreed that power Doppler clearly is superior to color Doppler technique for evaluation of the anatomy of orbital arteries and veins. 相似文献
978.
J. M. Johnston P. Grondziowski R. M. Windisch R. A. Eder L. Lytle 《Acta diabetologica》1995,32(4):213-216
A feasibility study was undertaken to evaluate laboratory phlebotomists performing bedside glucose monitoring (BGM) over a
3-month period on a medical and surgical floor. Specific questions included: feasibility of providing testing on a 24-h basis,
accuracy, appropriate utilization, effect on patient care, and an analysis of cost. In all, 1975 tests were performed on 114
patients. BGM results were within 15% of the laboratory's result 97% of the time. Patient and physician satisfaction was high.
Although the cost of BGM is slightly higher than a laboratory glucose test, its use appeared to reduce the length of hospital
stay by 0.47 days. Practical information on initiating a highly successful BGM program is provided. 相似文献
979.
Recent reports suggest that oxygen radical-induced lipid peroxidation plays a role in the retrograde degeneration of motor neurons following facial nerve axotomy in the neonatal rat. The purpose of the present study was to explore this notion further by testing the neuroprotective properties of two novel brain-penetrating, lipid peroxidation inhibitors, U-101033E and U-104067F, in this model of neuronal degeneration. In Experiment 1, 14-day-old rats were pretreated with 3, 10, or 30 mg/kg U-101033E (po) 10 min before right facial nerve axotomy (Day 0) and then posttreated once a day from Day 1 to Day 6, and once every other day from Day 8 to Day 21. Rats were sacrificed 21 days postaxotomy and surviving cholinergic cell bodies were identified using choline acetyltransferase immunocytochemistry. Both 10 and 30 mg/kg U-101033E significantly enhanced motor neuron survival, with survival rates of 65.9–88.9% being noted in comparison to 51.7–62% survival in vehicle controls (P ≤ 0.05). Experiment 2 demonstrated a significant neuroprotective effect of 10 and 30 mg/kg U-104067F using the same dosing schedule. Experiment 3 was designed to test whether shorter periods of drug exposure (e.g., 5 or 7 days) would be sufficient to preserve motor neurons in rats treated with 10 mg/kg U-101033E. The results suggested that as little as 5 days of drug treatment is sufficient to enhance motor neuron survival. Finally, Experiment 4 demonstrated an 18–19% increase in motor neuron survival in rats treated with 10 and 30 mg/kg U-104067F for 5 consecutive days postaxotomy. Taken together, the attenuation of motor neuron degeneration by the two pyrrolopyrimidine lipid peroxidation inhibitors, U-101033E and U-104067F, lends support to the notion that lipid peroxidation contributes to the pathogenesis of axotomy-induced neurodegeneration. 相似文献
980.
Summary
Candida endocarditis is an unusual but severe complication of systemic infection caused byCandida albicans and occasionally by other fungal species. We describe seven cases that occurred during a period of 20 years in western Sweden. In four cases infections were located on prosthetic valves and in three cases native valves were involved. Three patients died of the disease in the acute phase. A definite diagnosis was established in one of four survivors. This patient had an aortic valve endocarditis and a saddle embolisation and was treated with immediate surgery, followed by intensive treatment with liposomal amphotericin B + flucytosine. Fungal endocarditis is still a serious disease with a high mortality and whenever the diagnosis is suspected, antifungal therapy must be started and transesophageal sonography should be performed to visualize vegetations. Immediate surgery should be considered.
Pilzendokarditis — Bericht über sieben Fälle und kurze Literaturübersicht
Zusammenfassung DieCandida-Endokarditis ist eine seltene, aber schwere Komplikation einer systemischen Infektion durchCandida albicans und gelegentlich auch durch andere Pilzspezies. Wir berichten über sieben Fälle, die in einem Zeitraum von 20 Jahren in Westschweden beobachtet wurden. In vier Fällen waren Klappenprothesen und in drei Fällen natürliche Klappen betroffen. Drei Patienten starben in der akuten Phase an der Krankheit. Bei einem der vier überlebenden Patienten konnte die Diagnose eindeutig gesichert werden. Dieser Patient hatte eine Aortenklappenendokarditis und einen reitenden Embolus. Er wurde sofort operiert und hochdosiert mit liposomalem Amphotericin B und mit Flucytosin behandelt. Die Pilzendokarditis ist nach wie vor eine ernste, mit hoher Letalität belastete Krankheit. Die antimykotische Therapie muß bereits beim ersten Verdacht begonnen werden. Um Vegetationen nachzuweisen, sollte die transösophageale Sonographie durchgeführt werden. Ein sofortiges chirurgisches Eingreifen ist zu erwägen.相似文献