全文获取类型
收费全文 | 1030篇 |
免费 | 63篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 49篇 |
妇产科学 | 9篇 |
基础医学 | 67篇 |
口腔科学 | 13篇 |
临床医学 | 158篇 |
内科学 | 271篇 |
皮肤病学 | 19篇 |
神经病学 | 27篇 |
特种医学 | 232篇 |
外科学 | 113篇 |
综合类 | 33篇 |
预防医学 | 80篇 |
眼科学 | 8篇 |
药学 | 47篇 |
中国医学 | 2篇 |
肿瘤学 | 27篇 |
出版年
2022年 | 4篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 13篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 17篇 |
2014年 | 25篇 |
2013年 | 31篇 |
2012年 | 28篇 |
2011年 | 17篇 |
2010年 | 29篇 |
2009年 | 28篇 |
2008年 | 25篇 |
2007年 | 58篇 |
2006年 | 25篇 |
2005年 | 22篇 |
2004年 | 19篇 |
2003年 | 21篇 |
2002年 | 23篇 |
2001年 | 23篇 |
2000年 | 15篇 |
1999年 | 21篇 |
1998年 | 63篇 |
1997年 | 38篇 |
1996年 | 62篇 |
1995年 | 45篇 |
1994年 | 40篇 |
1993年 | 51篇 |
1992年 | 14篇 |
1991年 | 10篇 |
1990年 | 23篇 |
1989年 | 31篇 |
1988年 | 35篇 |
1987年 | 41篇 |
1986年 | 36篇 |
1985年 | 30篇 |
1984年 | 20篇 |
1983年 | 12篇 |
1982年 | 13篇 |
1981年 | 27篇 |
1980年 | 20篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 15篇 |
1976年 | 7篇 |
1975年 | 9篇 |
1974年 | 4篇 |
1972年 | 3篇 |
排序方式: 共有1156条查询结果,搜索用时 15 毫秒
11.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
12.
13.
麻醉深度监测是外科手术中必不可少的步骤之一。目前已经提出多种监测麻醉深度的脑电信号分析方法,尤其熵方法得到了广泛的关注。提出一种新的麻醉深度监测方法-希尔伯特黄熵,先用经验模态分解—希尔伯特黄变换处理脑电信号获取希尔伯特黄边际谱,再根据香农熵定义得到希尔伯特黄熵。对19个接受吸入药物七氟醚麻醉的病人脑电信号的希尔伯特黄熵和时频均衡谱熵进行计算、测试和比较,结果表明:希尔伯特黄熵能够更准确的区分麻醉和清醒状态,更适合于麻醉深度监测。 相似文献
14.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
15.
16.
Jolinda LD Schram Joost Oude Groeniger Merel Schuring Karin I Proper Sandra H van Oostrom Suzan JW Robroek Alex Burdorf 《Scandinavian journal of work, environment & health》2021,47(2):127
Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce. 相似文献
17.
There is increasing use of polymerase chain reaction techniques to diagnose infection. We report the use of polymerase chain reaction using a generic section of the bacterial 16S rDNA gene--followed by nucleotide sequencing--to determine the species of the infecting bacteria. In the first case, the clinical and microbiological diagnosis of meningococcal septicaemia was in agreement with the results from polymerase chain reaction technique. In the second case, a Yersinia enterocolitica bacteremia was detected by the polymerase chain reaction technique, but missed with conventional blood culture techniques. 相似文献
18.
FJ Cowan JT Warner LM Lowes JP Riberio JW Gregory 《Archives of disease in childhood》1997,77(2):109-114
AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care. 相似文献
19.
FJ Cowan JT Warner FD Dunstan WD Evans JW Gregory HR Jenkins 《Archives of disease in childhood》1997,76(4):325-329
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. 相似文献
20.
BA Evans IA Hughes CL Bevan MN Patterson JW Gregory 《Archives of disease in childhood》1997,76(6):529-531
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone. 相似文献