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排序方式: 共有217条查询结果,搜索用时 12 毫秒
41.
A recent report from the Institute of Medicine of the National Academies (IOM) calls for states to amend regulations on the practice of advanced practice registered nurses (APRNs). This article reviews the roles of APRNs, the IOM recommendations, and efforts by national and state stakeholders to remove legal barriers to APRN practice. 相似文献
42.
Benjamin N Greenwood Teresa E Foley Heidi E W Day Daniel Burhans Leah Brooks Serge Campeau Monika Fleshner 《Neuropsychopharmacology》2005,57(5):559-568
BACKGROUND: Altered serotonergic (5-HT) neurotransmission is implicated in the antidepressant and anxiolytic properties of physical activity. In the current study, we investigated whether physical activity alters factors involved in the regulation of central 5-HT neural activity. METHODS: In situ hybridization was used to quantify levels of 5-HT transporter (5-HTT), 5-HT(1A), 5-HT(1B), and alpha(1b)-adrenergic receptor (alpha(1b) ADR) messenger ribonucleic acids (mRNAs) in the dorsal (DRN) and median raphe (MR) nuclei of male Fischer rats after either sedentary housing or 3 days, 3 weeks, or 6 weeks of wheel running. RESULTS: Wheel running produced a rapid and lasting reduction of 5-HT(1B) mRNA in the ventral DRN. Three weeks of wheel running decreased 5-HTT mRNA in the DRN and MR and increased alpha(1b) ADR mRNA in the DRN. After 6 weeks of wheel running, 5-HTT mRNA remained reduced, but alpha(1b) ADR mRNA returned to sedentary levels. Serotonin(1A) mRNA was increased in the MR and certain DRN subregions after 6 weeks only. CONCLUSIONS: Data suggest that the central 5-HT system is sensitive to wheel running in a time-dependent manner. The observed changes in mRNA regulation in a subset of raphe nuclei might contribute to the stress resistance produced by wheel running and the antidepressant and anxiolytic effects of physical activity. 相似文献
43.
LB Jardim R Palma-Dias LCS Silva P Ashton-Prolla R Giugliani 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(8):943-946
We attempted to evaluate the role of maternal hyperphenylalaninaemia (HPA) as an isolated cause of mental retardation and microcephaly in children. This transversal study observed the plasma phenylalanine from mothers of 161 children with mental retardation and/or microcephaly of unknown origin. In this sample, we found two women with previously undiagnosed HPA, a frequency (2/161) higher than expected for our general population (1:12 500) ( p < 0.001). We concluded that the plasma phenylalanine levels should be determined during preconceptional evaluation of every woman of reproductive age that already has had a child affected either by mental retardation or microcephaly of unknown cause. It is particularly significant where women currently having their pregnancies have not been screened for phenylketonuria as newborns, as happens in most developing countries. 相似文献
44.
45.
Schwartz LB; Chiu AS; Courtney M; Krey L; Schmidt-Sarosi C 《Human reproduction (Oxford, England)》1997,12(1):45-50
To evaluate embryonic and endometrial factors for their value in predicting
pregnancy outcome in in-vitro fertilization (IVF) and embryo transfer, a
retrospective data collection and prospective uterine artery colour Doppler
imaging study was performed in a university-based IVF-embryo transfer
programme setting. A total of 210 patients were included and grouped as
follows: (I) IVF with controlled ovarian stimulation (214 cycles); (II)
frozen-thaw cycle of autologous embryos (30 cycles); (III) oocyte donation,
no cryopreservation (12 cycles); (IV) frozen-thaw cycle with embryos from
donated oocytes (10 cycles). Embryo quality was significantly better in
pregnant than non-pregnant cycles (group I, P = 0.0104; groups II-IV, P =
0.0418). The endometrial echo was significantly thicker in pregnant versus
non-pregnant patients in group I (P = 0.0059), but not in groups II-IV (P =
0.741). Past uterine surgery or abnormalities had no effect on pregnancy
outcome. There were no significant differences in mean uterine artery
resistance index or peak systolic velocity in pregnant versus non-pregnant
patients in groups II-IV. Thus, embryo quality is the most reliable
predictor of pregnancy outcome. Endometrial measurements were significantly
thicker in subsequently pregnant patients only in group I, where the
endometrium reflects the hormonal environment. Doppler parameters were not
useful in predicting pregnancy outcome.
相似文献
46.
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48.
Lack of a co-promoting effect of a 60 Hz magnetic field on skin tumorigenesis in SENCAR mice 总被引:1,自引:3,他引:1
Sasser LB; Anderson LE; Morris JE; Miller DL; Walborg EF Jr; Kavet R; Johnston DA; DiGiovanni J 《Carcinogenesis》1998,19(9):1617-1621
It has been proposed that extremely low frequency (ELF) magnetic fields may
enhance tumorigenesis through a co-promotional mechanism. This hypothesis
has been further tested using the two-stage model of mouse skin
carcinogenesis, i.e. 12-O-tetradecanoylphorbol-13-acetate (TPA)- induced
promotion of skin tumors in mice initiated by a single subcarcinogenic dose
of 7,12-dimethylbenz[a]anthracene. Experimentation described herein
utilized the SENCAR mouse and examined the effect of a magnetic field on
skin tumor promotion induced by three different doses of TPA within its
dose-response range, i.e. 0.85, 1.70 or 3.40 nmol, administered twice per
week. SENCAR mice (56/treatment group) were exposed to a 60 Hz magnetic
field having a flux density of 2 mT for 6 h/day for 5 days/week and
compared with mice exposed to the ambient magnetic field. Tumor incidence
and multiplicity were monitored weekly for 23 weeks of TPA promotion.
Statistical evaluation of the effects of the magnetic field on tumor
incidence and multiplicity did not reveal any statistically significant
effects; thus, within the sensitivity limits imposed by the animal model
and the exposure parameters employed, no promotional or co-promotional
effect of a 2 mT magnetic field on skin tumor development in SENCAR mice
could be demonstrated.
相似文献
49.
P Lu T Mamiya LL Lu A Mouri LB Zou T Nagai M Hiramatsu T Ikejima T Nabeshima 《British journal of pharmacology》2009,157(7):1270-1277
Background and purpose:
Accumulated evidence suggests that oxidative stress is involved in amyloid β (Aβ)-induced cognitive dysfunction. Silibinin (silybin), a flavonoid derived from the herb milk thistle (Silybum marianum), has been shown to have antioxidative properties; however, it remains unclear whether silibinin improves Aβ-induced neurotoxicity. In the present study, we examined the effect of silibinin on the memory impairment and accumulation of oxidative stress induced by Aβ25–35 in mice.Experimental approach:
Aggregated Aβ25–35 (3 nmol) was intracerebroventricularly administered to mice. Treatment with silibinin (2, 20 and 200 mg·kg−1, once a day, p.o.) was started immediately after the injection of Aβ25–35. Locomotor activity was evaluated 6 days after the Aβ25–35 treatment, and cognitive function was evaluated in a Y-maze and novel object recognition tests 6–11 days after the Aβ25–35 treatment. The levels of lipid peroxidation (malondialdehyde) and antioxidant (glutathione) in the hippocampus were measured 7 days after the Aβ25–35 injection.Key results:
Silibinin prevented the memory impairment induced by Aβ25–35 in the Y-maze and novel object recognition tests. Repeated treatment with silibinin attenuated the Aβ25–35-induced accumulation of malondialdehyde and depletion of glutathione in the hippocampus.Conclusions and implications:
Silibinin prevents memory impairment and oxidative damage induced by Aβ25–35 and may be a potential therapeutic agent for Alzheimer''s disease. 相似文献50.