全文获取类型
收费全文 | 99053篇 |
免费 | 4028篇 |
国内免费 | 218篇 |
专业分类
耳鼻咽喉 | 1458篇 |
儿科学 | 3114篇 |
妇产科学 | 2502篇 |
基础医学 | 13438篇 |
口腔科学 | 2642篇 |
临床医学 | 6010篇 |
内科学 | 22794篇 |
皮肤病学 | 2782篇 |
神经病学 | 7697篇 |
特种医学 | 2230篇 |
外国民族医学 | 2篇 |
外科学 | 12441篇 |
综合类 | 543篇 |
一般理论 | 25篇 |
预防医学 | 11187篇 |
眼科学 | 2249篇 |
药学 | 7406篇 |
1篇 | |
中国医学 | 314篇 |
肿瘤学 | 4464篇 |
出版年
2023年 | 552篇 |
2022年 | 328篇 |
2021年 | 1623篇 |
2020年 | 824篇 |
2019年 | 1892篇 |
2018年 | 3329篇 |
2017年 | 1976篇 |
2016年 | 1889篇 |
2015年 | 2185篇 |
2014年 | 2312篇 |
2013年 | 3767篇 |
2012年 | 6379篇 |
2011年 | 6456篇 |
2010年 | 3304篇 |
2009年 | 2379篇 |
2008年 | 5314篇 |
2007年 | 5639篇 |
2006年 | 5489篇 |
2005年 | 5528篇 |
2004年 | 5072篇 |
2003年 | 4735篇 |
2002年 | 4494篇 |
2001年 | 3190篇 |
2000年 | 3407篇 |
1999年 | 2693篇 |
1998年 | 496篇 |
1997年 | 327篇 |
1996年 | 369篇 |
1992年 | 1301篇 |
1991年 | 1176篇 |
1990年 | 1111篇 |
1989年 | 981篇 |
1988年 | 906篇 |
1987年 | 904篇 |
1986年 | 832篇 |
1985年 | 807篇 |
1984年 | 600篇 |
1983年 | 477篇 |
1979年 | 598篇 |
1978年 | 356篇 |
1976年 | 340篇 |
1975年 | 362篇 |
1974年 | 531篇 |
1973年 | 493篇 |
1972年 | 434篇 |
1971年 | 390篇 |
1970年 | 473篇 |
1969年 | 435篇 |
1968年 | 418篇 |
1967年 | 376篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
A technique to anesthetize turtles with ether is presented, in which a plastic cannula is passed through the glottis into the trachea. This procedure avoids apnea and allows ether vapours obtained from a chamber to be introduced, by the animal respiratory movements or by means of a pump, into the animal lungs. The anesthesia is rapidly obtained and lasts from 45-90 minutes. The time of recovery from anesthesia ranged from 60-90 minutes. With this technique no deaths were observed and the same animal could be anesthetized repeatedly. 相似文献
62.
63.
64.
We have analyzed the cellular and humoral immunity to the mycobacterial 65 KDa heat shock protein (hsp65) in a group of Freund's Adjuvant-immunized rats with a limited susceptibility to Adjuvant arthritis. According to the arthritis indices during the period of study (35 days), two different groups of rats could be distinguished; a) autoimmune Adjuvant arthritic rats (AA), and b) Non-arthritic animals (NA), including both rats which did not display any disease symptoms and rats suffering mild transient inflammation. The cellular response to the immunizing agent (Mycobacterium tuberculosis) or the mitogen Concanavalin A was comparable between both groups of rats. However, we detected an impaired cellular response to the individual hsp65 antigen in the animals that did not develop the disease. On the contrary, the level of hsp65-specific antibodies was much higher in NA animals than in AA rats suggesting a protective role for the hsp65 specific antibodies. 相似文献
65.
J M Barbero A I Ezpeleta M López Gil J L Barroso F García-Cosío 《Revista espa?ola de cardiología》1991,44(7):485-487
A 76-year-old woman with an inferior wall myocardial infarction, with right ventricular involvement, developed severe arterial hypoxemia with neurological involvement. Pulmonary edema or embolism and chronic obstructive pulmonary disease were ruled-out, and a right-to-left shunt was demonstrated by contrast echocardiography at the level of the foramen ovale. After inotropic support and oxygen supplementation, the patient recovered, although with significant neurological sequelae. No focal lesions were detected in the central nervous system by computerized tomography. Hypoxemia improved, coinciding with the disappearance of right-to-left shunt by contrast echocardiography. 相似文献
66.
Captopril is a suitable drug to treat high blood pressure in diabetic patients. This Angiotensin-Converting Enzyme Inhibitor (ACEI) is a vasodilator without tachycardia and saline retention. Furthermore, captopril is one of antihypertensive drugs with less adverse effects. It does not induce metabolic changes, improves glucose tolerance and brake the evolution of renal insufficiency. About 50-60% of patients are under control (DBP < 90 mmHg) with captopril monotherapy. In the present paper, were included 64 women and 16 men with diabetes mellitus and mild-moderate hypertension, I-II phase WHO. The average age (mean +/- S.D.) was 66.6 +/- 9.2 years. All patients were treated with 25 mg/12 h of captopril, for one month. If blood pressure was not under control, captopril treatment enhanced to 50 mg/12 h during second month. After this period of two months, patients under control were got out of this study. 37 patients (46.25%) needed a second drug. In randomized form, 20 patients associated 25 mg HCTZ one time a day (CAP + HCTZ); and 17 patients associated 20 mg/12 h of nifedipine retard (CAP + NIF). The study continued for 4 months more. Both treatments reduced blood pressure in significant form without changes statistical significant in the heart rate, weight, glycemia, cholesterol, triglycerides, c-HDL, uric acid, creatinine, Na+ and K+ blood levels. CAP + HCTZ controlled (DBP < 90 mHg) 85% and CAP + NIF 81.25% of patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
67.
We compared three different microsurgical vasovasostomy techniques on the rat vas deferens using absorbable and non-absorbable sutures and a fibrin adhesive technique. The best method was an extramucosal technique over a splint using vicryl. The worst results were seen using adhesive. 相似文献
68.
The aim of the study was the investigation of the biochemical condition of elements likely to directly participate in active
closing of the urethral lumen. We estimated glycogenolysis in urinary bladder, perivesical connective tissue and levator ani
muscle (LAM) samples obtained intraoperatively from 80 stress incontinent women. Glycogen content as well as activities of
active and total glycogen phosphorylase and acid exo-1,4-alpha-glucosidase were measured. Material from the urinary bladder
and perivesical connective tissue was insignificantly altered, and glycogen contents in the bladder (2.03±1.38 g/100 g wet
tissue) were considered to be normal. In the LAM glycogenolysis was much more activated than in other tissues (p<0.001 by
Fischer's exact test). Of LAM specimens 78% (22/28) revealed imbalanced biochemistry of glycogen with activation of hydrolytic
decomposition. We conclude that stress urinary incontinence in women is frequently associated with metabolic alterations in
the periurethral striated fibres. This study indirectly supports our recent hypothesis on the pathogenesis of the disease
in terms of muscle fibre type transitions. 相似文献
69.
V Rafnsson S G Jóhannesdóttir H Oddsson H Benediktsson H Tulinius G Magnússon 《Scandinavian journal of work, environment & health》1988,14(3):197-200
A retrospective cohort study of mortality and cancer morbidity was carried out among 295 marine engineers and 182 machinists with special regard to cancer of the lung. The cohort was defined as all graduates from engineering and machinists school in Iceland during 1936-1955. During vocational training, as well as in their professional lives, marine engineers and machinists are exposed to asbestos, different kinds of mineral oils, and exhaust gases with marked individual variation as regards mode and magnitude of exposure. For deaths occurring between 1951 and 1982 information was obtained from the Statistical Bureau of Iceland. Significantly increased standardized mortality ratios were determined for cancer of the trachea, bronchus, and lung for the entire cohort. Record linkage with the Cancer Register revealed 36 cancers in the period 1955-1982. No statistically significant excess was found for the overall cancer incidence or for the incidence of cancer at any particular site. A special survey of smoking status showed that cigarette smoking was not as common among the subjects of the cohort as among the general male population in Reykjavik. These results support the suggestion that the increased mortality of lung cancer in the study group had a causal relationship to occupational exposure, particularly to asbestos exposure. 相似文献
70.