全文获取类型
收费全文 | 5022篇 |
免费 | 380篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 94篇 |
儿科学 | 140篇 |
妇产科学 | 135篇 |
基础医学 | 604篇 |
口腔科学 | 185篇 |
临床医学 | 538篇 |
内科学 | 873篇 |
皮肤病学 | 73篇 |
神经病学 | 235篇 |
特种医学 | 572篇 |
外科学 | 696篇 |
综合类 | 88篇 |
一般理论 | 6篇 |
预防医学 | 418篇 |
眼科学 | 49篇 |
药学 | 373篇 |
1篇 | |
肿瘤学 | 338篇 |
出版年
2022年 | 32篇 |
2021年 | 83篇 |
2020年 | 51篇 |
2019年 | 79篇 |
2018年 | 71篇 |
2017年 | 71篇 |
2016年 | 83篇 |
2015年 | 97篇 |
2014年 | 130篇 |
2013年 | 164篇 |
2012年 | 234篇 |
2011年 | 264篇 |
2010年 | 144篇 |
2009年 | 129篇 |
2008年 | 201篇 |
2007年 | 226篇 |
2006年 | 195篇 |
2005年 | 198篇 |
2004年 | 165篇 |
2003年 | 189篇 |
2002年 | 141篇 |
2001年 | 120篇 |
2000年 | 112篇 |
1999年 | 106篇 |
1998年 | 127篇 |
1997年 | 118篇 |
1996年 | 102篇 |
1995年 | 89篇 |
1994年 | 59篇 |
1993年 | 83篇 |
1992年 | 58篇 |
1991年 | 69篇 |
1990年 | 78篇 |
1989年 | 101篇 |
1988年 | 90篇 |
1987年 | 89篇 |
1986年 | 105篇 |
1985年 | 121篇 |
1984年 | 83篇 |
1983年 | 76篇 |
1982年 | 49篇 |
1981年 | 59篇 |
1980年 | 55篇 |
1978年 | 45篇 |
1977年 | 48篇 |
1976年 | 53篇 |
1975年 | 46篇 |
1972年 | 29篇 |
1971年 | 30篇 |
1966年 | 30篇 |
排序方式: 共有5418条查询结果,搜索用时 265 毫秒
11.
12.
Many people die in emergency departments (EDs) across the United States from sudden illnesses or injuries, an exacerbation of a chronic disease, or a terminal illness. Frequently, patients and families come to the ED seeking lifesaving or life-prolonging treatment. In addition, the ED is a place of transition-patients usually are transferred to an inpatient unit, transferred to another hospital, or discharged home. Rarely are patients supposed to remain in the ED. Currently, there is an increasing amount of literature related to end-of-life care. However, these end-of-life care models are based on chronic disease trajectories and have difficulty accommodating sudden-death trajectories common in the ED. There is very little information about end-of-life care in the ED. This article explores ED culture and characteristics, and examines the applicability of current end-of-life care models. 相似文献
13.
Ohne Zusammenfassung 相似文献
14.
Background - A case of primary thyroid T cell lymphoma leading to lethal tracheal perforation during chemotherapy is described. 相似文献
15.
Both cyproterone acetate (CPA) and the gonadotrophin-releasing hormone
agonist (GnRHa) have been shown to be effective for the treatment of
hirsutism. We wished to compare the effectiveness of CPA in two standard
doses with GnRHa and add-back therapy and to compare the length of
remission after these treatments. A total of 60 hirsute hyperandrogenic
women was assigned to the following treatment groups: CPA 2 mg with 35
microg of ethinylestradiol for 21 days each month (Diane group), CPA 50 mg,
days 5-15, and ethinylestradiol 50 microg, days 5-25, each month (CPA
group) or Decapeptyl 3.75 mg i.m. every 28 days with the addition of
conjugated oestrogen 0.625 mg, days 1-21, and medroxyprogesterone acetate
10 mg, days 12-21 (GnRHa group). Hirsutism was graded by the
Ferriman-Gallwey-Lorenzo (FGL) index and anagen hair shaft diameters and
serum luteinizing hormone (LH) and testosterone were assessed before and
every 3 months during and after treatment. All women were treated for 1
year with 1 year follow-up. At baseline hirsutism and endocrine patterns
were similar in all groups. After one year of treatment, hirsutism
decreased in all groups but the changes were greater (P <0.05) in the
CPA and GnRHa groups than in the Diane group. Serum LH and testosterone
were lowest in the GnRHa group. After withdrawal, hirsutism increased
rapidly in the Diane and CPA groups and after 6 months, FGL scores and hair
shaft diameters were similar to pretreatment values. In the GnRHa group,
hirsutism increased more gradually and after 1 year of withdrawal, FGL
scores and hair diameters were significantly (P <0.05) less than
pretreatment values. Serum LH and testosterone increased rapidly in all
three groups reaching pretreatment values by 6 months. These data suggest
equal efficacy of the GnRHa and the high dose CPA regimen for the treatment
of hirsutism in hyperandrogenic women. GnRHa with add-back treatment
appears to result in a longer remission of hirsutism in comparison with
CPA.
相似文献
16.
17.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献
18.
Changes in regional ventilation and perfusion of the lung after endoscopic laser treatment. 总被引:4,自引:2,他引:2
下载免费PDF全文
![点击此处可从《Thorax》网站下载免费的PDF全文](/ch/ext_images/free.gif)
To determine whether endoscopic laser treatment improves both ventilation and perfusion in patients with advanced lung cancer, krypton-81m ventilation and technetium-99m labelled macro-aggregate perfusion scanning was performed immediately before and two or four days after treatment in a consecutive series of 28 patients. Twelve patients had not received any other treatment before laser therapy and 16 had undergone previous treatments that included radiotherapy. Ventilation and perfusion were quantified by expressing the number of counts in the affected lung as a percentage of the total counts. Ventilation and perfusion improved after laser treatment in 23 patients (82%). The mean ventilation score in the affected lung rose by 50% (p less than 0.001) and the mean perfusion score rose by 24% (p less than 0.001). Incremental changes in ventilation and perfusion scores were positively correlated (r = 0.80). Mean spirometric values, six minute walking distance, the Karnofsky performance index, and breathlessness and wellbeing scores also improved significantly. Patients with main bronchial obstruction who had had no radiotherapy showed the most striking improvements. It is concluded that the removal of intraluminal tumour from the bronchial tree leads to matched improvements in ventilation and perfusion in most patients and that this is associated with valuable improvement in symptoms. 相似文献
19.
20.