全文获取类型
收费全文 | 532篇 |
免费 | 59篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 50篇 |
妇产科学 | 6篇 |
基础医学 | 67篇 |
口腔科学 | 29篇 |
临床医学 | 56篇 |
内科学 | 124篇 |
皮肤病学 | 19篇 |
神经病学 | 26篇 |
特种医学 | 82篇 |
外科学 | 39篇 |
综合类 | 17篇 |
预防医学 | 11篇 |
眼科学 | 5篇 |
药学 | 40篇 |
肿瘤学 | 17篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 9篇 |
2018年 | 11篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 14篇 |
2014年 | 16篇 |
2013年 | 24篇 |
2012年 | 23篇 |
2011年 | 16篇 |
2010年 | 41篇 |
2009年 | 31篇 |
2008年 | 22篇 |
2007年 | 17篇 |
2006年 | 19篇 |
2005年 | 17篇 |
2004年 | 11篇 |
2003年 | 10篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 9篇 |
1998年 | 28篇 |
1997年 | 34篇 |
1996年 | 33篇 |
1995年 | 27篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 12篇 |
1988年 | 13篇 |
1987年 | 15篇 |
1986年 | 10篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 10篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1968年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有597条查询结果,搜索用时 15 毫秒
531.
532.
H Massiou C Tzourio M El Amrani MG Bousser 《Cephalalgia : an international journal of headache》1997,17(1):37-39
Verbal scales are currently used as efficacy parameters in acute migraine trials. In order to determine the correlation between headache intensity, functional disability, and relevant pain reduction, 100 patients completed a questionnaire. Our results showed that a verbal scale of headache intensity alone has different implications from one that includes pain intensity and functional ability. The reduction from a moderate to a mild headache was satisfactory to only 15% of the patients. In contrast, 77% of patients were satisfied when the headache intensity was reduced from severe to mild. These findings imply that, in assessing the efficacy of drugs used for migraine, a redaction in pain intensity from moderate to mild should not be considered as a good outcome. 相似文献
533.
Gadow EC; Paz JE; Lopez-Camelo JS; Dutra MG; Queenan JT; Simpson JL; Jennings VH; Castilla EE 《Human reproduction (Oxford, England)》1998,13(7):1991-1995
Unintended pregnancies are accepted as associated with social, maternal and
perinatal risks, but few data exist in South America. In a selected network
of hospitals participating in the ECLAMC (Spanish acronym for Latin
American Collaborative Study of Congenital Malformations), the frequency of
unintended pregnancies was 49.8% in 5155 mothers of normal liveborns, as
interviewed in the post-partum period (1992-1994). Compared with the
intended pregnancy group, these mothers were more frequently multiparous,
conceived easily, had a surprisingly higher mean maternal age, lower
educational level, and Black ancestors. The frequency of mistimed
pregnancies was the highest among primiparae. No adverse perinatal outcome
could be found with regard to low birthweight (< 2500 g), prematurity
(< 37 weeks), and early neonatal death. The rates of Caesarean delivery,
twinning and sex ratio were similar in intended and unintended groups.
Logistic regression analysis showed that maternal education could be a
confounding factor associated with other maternal variables. The rate of
unintended pregnancies in the present study is significantly higher than
that described for other regions. Knowledge of the characteristics of women
experiencing unintended pregnancies would allow proper public health
strategies.
相似文献
534.
535.
An undetectable source of technical error that could lead to false negative results in enzyme linked immunosorbent assay of antibodies to HIV-1 总被引:1,自引:0,他引:1
Since the institution of routine testing for antibodies to Human Immunodeficiency Virus (HIV) using the enzyme-linked immunosorbent assay (ELISA), the specificity and sensitivity of this assay system has received significant scrutiny. During previous use of this methodology, we have quantified rates of false biological positive results using commercial kit assays in a normal donor population. In this study, we have identified a potential source for false negative results. Using multiple lots of two different commercial ELISA kits, the absorbance readings at the test end point could not differentiate between normal non-reactive donor samples and blanks containing no sample. These results occur using normal donor samples, even though the assays could distinguish between blank wells and the manufacturers' "normal controls", provided with the assay. Our findings suggest that a technical pipetting error is presently undetectable, either visually or by statistical methods, and could permit an untested, potentially HIV-1 positive, unit to be released into the transfusable blood supply. A possible solution is suggested. 相似文献
536.
Calcification of the ductus venosus: a cause of right upper quadrant calcification in the newborn 总被引:1,自引:0,他引:1
The authors report three cases of ductus venosus calcification as an additional cause of vascular liver calcification in the newborn. All three infants had umbilical venous catheters. The calcification may be caused by extravasated fluids given through the catheter or by local trauma due to catheter insertion. An obliquely oriented, paravertebral "tram-track" calcification in the right upper quadrant, particularly in a premature infant with a history of umbilical venous catheterization, should suggest the diagnosis of calcified ductus venosus. 相似文献
537.
Cabrera Pivaral CE Martínez Ramírez A Vega López MG González Pérez G Muñoz De La Torre A 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(4):525-530
Nutritional practices of diabetics reflect both human behavior and the health culture of such patients. They also represent how the diabetic deals with the health/illness issue. The purpose of this survey was to identify and relate nutritional practices with metabolic control, age, sex, years of schooling, and time since diagnosis of illness. The sample was taken from 114 cases selected through systematic random sampling in five family practice units in Guadalajara. Using thirteen structured, coded, and quantified questions of the Likert type, the study evaluated nutritional practice with a range of 0-65. Results showed that 21% of the diabetics had appropriate nutritional practices (>31 points), and when related with years of schooling and time since diagnosis of illness, they showed statistically significant differences (p=0.05). Simple regression showed that 9% of metabolic control can be explained by nutritional practices. 相似文献
538.
539.
Seventy-one children with nocturnal enuresis were enrolled in a controlled trial. The children were allocated to two matched groups. Children in both groups used an enuresis alarm until the end of treatment. Children in the first group were treated with 40/^g of intranasal desmopressin (Desmospray) for up to 6 weeks at the start of treatment with the alarm. During the observation period before treatment there were 2.3 dry nights per week in both groups. At the end of treatment there was a significant difference in the mean number of dry nights per week between the two groups (6.3 in the alarm and desmopressin group and 4.8 in the alarm group) and also in the number of children becoming reliably dry. The combination of desmopressin and alarm was particularly helpful for children with severe wetting and those with family and behavioural problems. Desmopressin, enuresis alarm, nocturnal enuresis
MG Bradbury, Department of Paediatrics and Child Health, St James's University Hospital, Leeds LS9 7TF, UK 相似文献
MG Bradbury, Department of Paediatrics and Child Health, St James's University Hospital, Leeds LS9 7TF, UK 相似文献
540.
Maria V Croce Andrea G Colussi MG DE Bravo Michel R Price Amanda Segal-Eiras 《Pathology oncology research : POR》1998,4(4):259-266
The most common clinical form of lung cancer is a disseminated disease with distant metastases; several years of cancer progression
precede presentation, and this ultimately limits the efficacy of curative therapy. In this immunohistochemical study, we examined
a mucinous adenocarcinoma cell line, maintained by xenogeneic transplantation, and a spontaneous metastatic variant which
produces distant tumors (in liver, spleen and kidney). The aim was to investigate possible parameters which characterize the
metastatic process. Histopathological comparison between the two subcutaneous transplanted tumor lines showed that both lines
presented a similar cellular morphology, a different pattern of cellular growth and an increased vascularization in the metastatic
line with respect to its parent. All the tumor sections expressed differential immune reactivity with monoclonal antibodies
against Lewis y (MAb C14), sialyl-Lewis x (MAb SNH3) and Lewis x (MAb FH2) determinants. Neither expressed MUC 1 mucins detectable
with monoclonal antibodies reactive with the mucin protein core (MAbs C595 and SM3) nor was carcinoembryonic antigen (MAb
C365) expressed. Neoplastic cells were reactive with an anti-pan cytokeratin monoclonal antibody confirming their epithelial
histogenesis. Our findings have been evaluated with respect to defining metastatic phenotypes in lung cancer by examination
of distinct histopathological and immunological parameters. 相似文献