全文获取类型
收费全文 | 2771篇 |
免费 | 195篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 229篇 |
妇产科学 | 50篇 |
基础医学 | 262篇 |
口腔科学 | 79篇 |
临床医学 | 243篇 |
内科学 | 644篇 |
皮肤病学 | 29篇 |
神经病学 | 149篇 |
特种医学 | 512篇 |
外科学 | 239篇 |
综合类 | 56篇 |
一般理论 | 5篇 |
预防医学 | 127篇 |
眼科学 | 119篇 |
药学 | 102篇 |
中国医学 | 3篇 |
肿瘤学 | 138篇 |
出版年
2023年 | 9篇 |
2022年 | 12篇 |
2021年 | 14篇 |
2020年 | 15篇 |
2019年 | 27篇 |
2018年 | 28篇 |
2017年 | 24篇 |
2016年 | 34篇 |
2015年 | 56篇 |
2014年 | 45篇 |
2013年 | 89篇 |
2012年 | 65篇 |
2011年 | 77篇 |
2010年 | 104篇 |
2009年 | 87篇 |
2008年 | 68篇 |
2007年 | 71篇 |
2006年 | 71篇 |
2005年 | 68篇 |
2004年 | 55篇 |
2003年 | 54篇 |
2002年 | 59篇 |
2001年 | 54篇 |
2000年 | 68篇 |
1999年 | 57篇 |
1998年 | 148篇 |
1997年 | 128篇 |
1996年 | 130篇 |
1995年 | 100篇 |
1994年 | 76篇 |
1993年 | 85篇 |
1992年 | 51篇 |
1991年 | 57篇 |
1990年 | 49篇 |
1989年 | 96篇 |
1988年 | 76篇 |
1987年 | 82篇 |
1986年 | 82篇 |
1985年 | 78篇 |
1984年 | 49篇 |
1983年 | 52篇 |
1982年 | 52篇 |
1981年 | 34篇 |
1980年 | 39篇 |
1979年 | 42篇 |
1978年 | 23篇 |
1977年 | 27篇 |
1976年 | 28篇 |
1975年 | 27篇 |
1969年 | 10篇 |
排序方式: 共有2989条查询结果,搜索用时 18 毫秒
41.
Anxiety during pregnancy and fetal attachment after in-vitro fertilization conception 总被引:3,自引:4,他引:3
McMahon CA; Ungerer JA; Beaurepaire J; Tennant C; Saunders D 《Human reproduction (Oxford, England)》1997,12(1):176-182
The aim of this study was to compare 70 couples who had conceived by in-
vitro fertilization (IVF) with 63 matched controls for the prevalence of
anxiety and quality of attachment to the baby during pregnancy. Results for
mothers showed no group differences using a global measure of anxiety, the
Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific
measures revealed significantly higher levels of anxiety in IVF mothers
about the survival and normality of their unborn babies, about damage to
their babies during childbirth and about separating from their babies after
birth. When IVF mothers were differentiated according to the number of
treatment cycles, more differences in anxiety level were revealed, with
most increases occurring in mothers who had experienced two or more
treatment cycles. IVF fathers did not differ from controls on the global
anxiety measure. No data on pregnancy-specific anxiety were available for
fathers. Neither IVF mothers nor IVF fathers differed from controls on
measures of attachment to the baby during pregnancy. Results are discussed
in the context of the need for researchers to employ differentiated and
issue-specific measures to identify concerns that may be unique to IVF
couples. Clinical implications regarding the need for psychological support
during pregnancy are also discussed.
相似文献
42.
43.
44.
45.
Hungry rats display the characteristic "satiety sequence" after drinking a glucose solution: The end of ingestion is accompanied by grooming and exploring, followed by resting. With saccharin solutions over a range of concentrations, however, ingestion is accompanied and followed by persistent grooming and exploring; resting rarely occurs. Gastric preloads of glucose solution promote resting to reinstate the "satiety sequence" after a bout of saccharin ingestion. Therefore, the systemic effects of glucose are sufficient to promote resting. In the absence of postingestive factors, the "satiety sequence" is incomplete following saccharin ingestion as it is after sham-feeding. 相似文献
46.
Childhood leukemia. Emotional impact on patient and family 总被引:6,自引:0,他引:6
C M Binger A R Ablin R C Feuerstein J H Kushner S Zoger C Mikkelsen 《The New England journal of medicine》1969,280(8):414-418
47.
Antiphospholipid antibodies and the outcome of pregnancy after the first in-vitro fertilization and embryo transfer cycle 总被引:1,自引:1,他引:1
Balasch J; Creus M; Fabregues F; Civico S; Reverter JC; Carmona F; Tassies D; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(5):1180-1183
Increased antiphospholipid antibody prevalence has been demonstrated by a
number of recent studies in in-vitro fertilization (IVF) patients but the
potential effects of antiphospholipid antibodies on the different
components of the reproductive process and the consideration of whether to
test IVF patients for antiphospholipid antibodies are controversial. The
present study was undertaken to investigate the possible association
between the presence of circulating antiphospholipid antibodies (namely the
lupus anticoagulant and anticardiolipin antibodies), among a series of 21
consecutive IVF patients having a clinical spontaneous abortion after their
first embryo transfer. As a control group (n=42), the nearest IVF cycle
resulting in an ongoing pregnancy before and after each miscarried IVF
cycle (i.e. the closest cycles in temporal relationship to the index cycle)
was used. One patient (4.8%) in the study group and two women (4.8%) among
controls were seropositive for antiphospholipid antibodies. These low and
similar seropositivity rates found in the two groups studied lead us to
conclude that antiphospholipid antibodies testing in IVF patients should be
considered only in those women having repeated failures of
implantation/clinical abortion after embryo transfer but not in an
infertile general population reaching an IVF programme.
相似文献
48.
Huisman JA; Paulussen RJ; Geurts TB; Odink J; Rekers H 《Human reproduction (Oxford, England)》1997,12(1):34-38
The objective was to demonstrate bioequivalence between s.c. and i.m.
administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio
3:1). In two randomized, single-centre, cross-over studies, 18 healthy
volunteers on each formulation were assigned to one of the two
administration sequences. Subjects were given single doses of one of the
above gonadotrophins after endogenous gonadotrophin production had first
been suppressed using high-dose oral contraceptive. Subsequently, rate
(Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone
(FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax
and AUC, analysis of variance (ANOVA) was performed on log-transformed data
and for tmax ANOVA was performed on ranks. Intramuscular and s.c.
injections of Humegon were bioequivalent with respect to the main
pharmacokinetic parameters, being AUC and Cmax of FSH absorption.
Intramuscular and s.c. injections of Normegon were bioequivalent with
respect to the AUC of FSH and not bioequivalent with respect to the Cmax of
FSH. For tmax of FSH as well as for most LH variables of both preparations,
bioequivalence could not be proven due to the high intra- and
interindividual variability and/or concentrations being close to the
detection limit. Thus, the main pharmacokinetic FSH variables after i.m.
and s.c. administration of Humegon and Normegon were bioequivalent.
相似文献
49.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
50.
Janice S. Lee Carol W. Bassim Harvey Kushner Ann G. Carr Pamela J. Gardner Laura A. Harney Kris Ann P. Schultz Douglas R. Stewart 《American journal of medical genetics. Part A》2019,179(9):1820-1825
Pathogenic germline variation in the microRNA processing gene DICER1 gives rise to an autosomal dominant, tumor‐predisposition disorder. Conditional deletion of Dicer1 in murine dental epithelium shows that it controls tooth patterning, size, number, and shape. The human dental phenotype of people with germline pathogenic variation in DICER1 is unknown. DICER1‐carriers (n = 57) and family controls (n = 55) were evaluated at the NIH Clinical Center dental clinic as part of a comprehensive medical evaluation. Digital panoramic radiographs, bite‐wing radiographs, and oral photographs were collected. A single observer, blind to DICER1 status, reviewed the dental records and determined the presence or absence of 11 dental characteristics as described in the clinic notes, radiographs, or oral photographs. Subjective phenotypes were reviewed on radiographs by two examiners (blind to DICER1 status) for the presence or absence of the dental characteristics to reduce inconsistencies. By simple association, bulbous crown, periodontitis, and taurodontism were all significant (p < .05). Logistic regression with chi‐square maximum likelihood estimates showed that bulbous crown and periodontitis remained significant. Recognition of these phenotypes may aid identification of individuals and families at risk for DICER1‐associated neoplasms. These findings may also guide dental care for individuals with germline DICER1 pathogenic variation. 相似文献