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991.
Integrin expression in normal and out-of-phase endometria 总被引:7,自引:6,他引:7
Creus M; Balasch J; Ordi J; Fabregues F; Casamitjana R; Quinto L; Coutifaris C; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(12):3460-3468
Integrins have recently been proposed as having a major role in endometrial
receptivity. Different patterns of integrin expression have been described
during the normal endometrial cycle, and the co- expression of several
integrins, mainly alpha1, alpha4 and beta3 has been considered as specific
to the 'window of implantation'. In the present study 55 infertile patients
underwent two endometrial biopsies during a single menstrual cycle. An
early biopsy was done on postovulatory days 6-8, and a late biopsy was
performed on postovulatory days 10 to 12. Histological dating as well as
immunohistochemical evaluation of alpha1, alpha4, beta1, beta3, beta5,
alpha(v)beta3 integrin expression and oestrogen and progesterone receptors
were determined in all endometrial biopsies. Oestradiol and progesterone
serum concentrations in serum were evaluated on the same days of the
endometrial samplings. Nine out of the 55 midluteal biopsies (16.4%) showed
out-of-phase endometria, but all biopsies were in phase in the late luteal
phase. Differences in integrin expression between in- and out-of-phase
biopsies were observed only for alpha(v)beta3 integrin glandular expression
during the midluteal phase. Alpha(v)beta3 integrin glandular expression was
found in all late luteal phase biopsies. Alpha(v)beta3 expression was
closely correlated with histological maturation of the endometrium
appearing suddenly at postovulatory day 6-7 and being expressed by all
endometria dated as postovulatory day > or = 8, irrespective of
midluteal endometrial biopsies being in phase or out of phase. No
differences in integrin expression were detected between patients with or
without endometriosis or between patients who became spontaneously pregnant
and those who did not. In conclusion, further studies are necessary before
patterns of integrin expression may offer an alternative to predict uterine
receptivity and implantation potential.
相似文献
992.
A randomized controlled trial of three low-dose gonadotrophin protocols for unexplained infertility 总被引:1,自引:4,他引:1
This randomized controlled trial assessed which of three low-intensity
ovulation induction protocols was associated with the highest rate of cycle
completion among infertile women undergoing intrauterine insemination (IUI)
with their husband's spermatozoa. Sixty-three women aged < or = 42 years
with normospermic partners participated in the study. The primary diagnosis
of infertility was unexplained in 89% of subjects, endometriosis in 6% and
tubal factor in 5%. Women were assigned to three groups according to
recombinant FSH dosage: group A received two ampoules (75 IU FSH per
ampoule) on cycle day 4, and one ampoule on days 6 and 8 (total four
ampoules); group B received two ampoules on days 4, 6 and 8 (total six
ampoules); group C received two ampoules on days 4, 6, 8 and 10 (total
eight ampoules). Daily ultrasound investigations began on cycle day 9-12
and human chorionic gonadotrophin (HCG) 5000 IU was administered when one
or two follicles > or = 18 mm were seen. IUI was scheduled for the next
day. HCG was given and/or ovulation shown to have occurred in 88 of 109
cycles attempted (81%) with no differences among the three dose groups. Two
singleton pregnancies occurred (2.3% per ovulatory cycle and 1.8% per cycle
start). There were no significant differences among the three regimes in
terms of cycle parameters, suggesting that an individualized and more
intensive approach to ovarian stimulation is necessary for many women with
unexplained infertility.
相似文献
993.
Haematocrit, leukocyte and platelet counts and the severity of the ovarian hyperstimulation syndrome 总被引:2,自引:1,他引:2
Fabregues F; Balasch J; Manau D; Jimenez W; Arroyo V; Creus M; Rivera F; Vanrell JA 《Human reproduction (Oxford, England)》1998,13(9):2406-2410
Previous studies have shown that severe ovarian hyperstimulation syndrome
(OHSS) is secondary to circulatory dysfunction due to the simultaneous
occurrence of increased vascular permeability and marked arteriolar
vasodilation which lead to an intense homeostatic stimulation of the
renin-aldosterone and sympathetic nervous systems and antidiuretic hormone
(ADH). In the present report, we have investigated the correlation between
changes in haematocrit concentration, and white blood cell (WBC) and
platelet counts and the severity of OHSS, as assessed by these markers of
effective intra- arterial blood volume, in a series of 50 patients. In
comparison with recovery values (4-5 weeks after hospital discharge), OHSS
patients showed arterial hypotension, tachycardia, oliguria, very high
plasma concentrations of renin, aldosterone, norepinephrine and ADH, and
increased mean haematocrit values and WBC and platelet counts. The
haematocrit concentration values were directly related to the plasma
concentrations of vasoactive substances (plasma renin activity,
aldosterone, norepinephrine and ADH) during OHSS (P < 0.001). In
contrast, no correlation was evident between WBC or platelet counts and
neurohormonal measurements during the syndrome. It is concluded that
haematocrit, but not WBC or platelet counts, can act as a biological marker
of the severity of OHSS as indicated by plasma measurement of
volume-dependent endogenous vasoactive substances.
相似文献
994.
Angelopoulos T; Krey L; McCullough A; Adler A; Grifo JA 《Human reproduction (Oxford, England)》1997,12(10):2208-2216
Although round spermatids have been studied extensively using staining
techniques and electron microscopy, little information is available about
their appearance in living conditions. We describe a method of collecting
and identifying round spermatids from ejaculates and testicular biopsies.
The validity of the selection procedure was confirmed by fluorescence
in-situ hybridization. Based on cell size, morphological characteristics of
nucleus and cytoplasm, and on the nucleus/cytoplasm ratio, we harvested a
population of cells that was 84% haploid. This procedure can be applied to
select spermatids for clinical or research purposes.
相似文献
995.
996.
A simplified serum-free method for preparation and cultivation of human granulosa-luteal cells 总被引:1,自引:0,他引:1
Figenschau Y; Sundsfjord JA; Yousef MI; Fuskevag OM; Sveinbjornsson B; Bertheussen K 《Human reproduction (Oxford, England)》1997,12(3):523-531
A simplified method for the preparation and long-term cultivation of
granulosa-luteal cells in serum-free medium is described. The cells were
harvested from women undergoing in-vitro fertilization, enriched by
sedimentation and dissociated by enzymatic treatment. We demonstrated, by
introducing a synthetic serum replacement (SSR2), that these primary cell
cultures cultivated in monolayers on an extracellular matrix may be used in
experiments exceeding 7 days with low cell loss and cell death. No adverse
effect on progesterone production was found. There was a high diversity in
progesterone production between cells from individual patients. After
several days in culture, the cells were challenged with human chorionic
gonadotrophin which revived the rapidly decreasing progesterone production.
We were unable to demonstrate an increase in cell number after 7 days of
cultivation when the cells were grown in medium supplemented with either
serum or SSR2. The mitogens epidermal growth factor and basic fibroblast
growth factor had no influence on proliferation. We also found that the
present method prevents leukocyte contamination in the granulosa-luteal
cell cultures. Compared with the common method based on the enrichment of
granulosa-luteal cells on a density gradient (Ficoll/Percoll), this method
saves time, labour and expense, in addition to augmenting purity.
相似文献
997.
Engle SJ; Womer DE; Davies PM; Boivin G; Sahota A; Simmonds HA; Stambrook PJ; Tischfield JA 《Human molecular genetics》1996,5(10):1607-1610
Complete hypoxanthine-guanine phosphoribosyl-transferase (HPRT) deficiency
in humans results in the Lesch-Nyhan syndrome which is characterized, among
other features, by compulsive self-injurious behavior. HPRT-deficient mice
generated using mouse embryonic stem cells exhibit none of the behavioral
symptoms associated with the Lesch- Nyhan syndrome. Administration of drugs
that inhibit adenine phosphoribosyltransferase (APRT) in HPRT-deficient
mice has produced the suggestion that deficiency of APRT in combination
with HPRT- deficiency in mice may lead to self-mutilation behavior [C.L. Wu
and D.W. Melton (1993) Nature Genet. 3, 235-240]. To test this proposition,
we bred HPRT-APRT-deficient mice. Although the doubly-deficient mice
excrete adenine and its highly insoluble derivative, 2,8- dihydroxyadenine,
which are also associated with human APRT deficiency, additional
abnormalities or any self-injurious behavior were not detected. Thus,
APRT-HPRT-deficient mice, which are devoid of any purine salvage pathways,
show no novel phenotype and are not a model for the behavioral
abnormalities associated with the Lesch-Nyhan syndrome as previously
suggested.
相似文献
998.
999.
Evaluation of the performance of hysterosalpingo contrast sonography in 500 consecutive, unselected, infertile women 总被引:1,自引:1,他引:1
Hamilton JA; Larson AJ; Lower AM; Hasnain S; Grudzinskas JG 《Human reproduction (Oxford, England)》1998,13(6):1519-1526
The performance of hysterosalpingo contrast sonography (Hy Co Sy) as a
first-line, outpatient investigation of tubal patency was examined in 500
consecutive, infertile women, at one centre. Hy Co Sy was completed in 463
(92.6%) cases, using a galactose microbubble contrast agent (Echovist-200)
and transvaginal sonography. Initial plain scanning identified adnexal
pathology in 198 women (39.6%). Examination with Echovist was attempted for
905 tubes and only 67 (7.4%) were not assessable; after the first 100 women
this decreased to 35 tubes (4.8%). A sonographic appearance compatible with
blocked tubes was found on 118 (14.1%) occasions but it was also possible
to identify variations in the appearance/filling/spilling patterns of
individual tubes which increased the number assessed as abnormal to 193
(23.0%). Comparison with laparoscopy and dye chromopertubation findings
from the past three years was possible for 185 (37%) women, representing
282 tubes, which gave Hy Co Sy an overall concordance rate of 85.8%,
sensitivity of 90.4%, specificity of 70.3%, positive predictive value of
91.2% and negative predictive value of 68.2%. Some 51.0% of women described
only mild discomfort and there were no significant postprocedure
complications. Hy Co Sy appears to be an acceptable first- line screen and
may select out women in whom more invasive investigations are likely to
reveal pathology.
相似文献
1000.
Linkage analysis of candidate regions for coeliac disease genes 总被引:5,自引:0,他引:5
Houlston RS; Tomlinson IP; Ford D; Seal S; Marossy AM; Ferguson A; Holmes GK; Hosie KB; Howdle PD; Jewell DP; Godkin A; Kerr GD; Kumar P; Logan RF; Love AH; Johnston S; Marsh MN; Mitton S; O'Donoghue D; Roberts A; Walker-Smith JA; Stratton MF 《Human molecular genetics》1997,6(8):1335-1339
A strong HLA association is seen in coeliac disease [specifically to the
DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account
for the increased risk seen in relatives of affected cases. One or more
genes at HLA-unlinked loci also predispose to coeliac disease and are
probably stronger determinants of disease susceptibility than HLA. A recent
study has proposed a number of candidate regions on chromosomes 6p23
(distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3,
19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked
susceptibility gene. We have examined these regions in 28 coeliac disease
families by linkage analysis. There was excess sharing of chromosome 6p
markers, but no support for a predisposition locus telomeric to HLA. No
significant evidence in favour of linkage to coeliac disease was obtained
for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or
22cen. There was, however, excess sharing close to D15S642. The maximum
non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for
linkage of coeliac disease to chromosome 15q26 is not strong, the well
established association between coeliac disease and insulin dependent
diabetes mellitus, together with the mapping of an IDDM susceptibility
locus (IDDM3) to chromosome 15q26, provide indirect support for this as a
candidate locus conferring susceptibility to coeliac disease in some
families.
相似文献