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991.
Yoshiki Aoshima Hiroyuki Sakakibara Taka-aki Suzuki Shunsuke Yamazaki Kayoko Shimoi 《Experimental Animals》2014,63(3):331-338
Recent studies have suggested the possibility that nocturnal light exposure affects many
biological processes in rodents, especially the circadian rhythm, an endogenous
oscillation of approximately 24 h. However, there is still insufficient information about
the physiological effects of nocturnal light exposure. In this study, we examined the
changes in gene expression and serum levels of plasminogen activator inhibitor-1 (PAI-1),
a major component of the fibrinolytic system that shows typical circadian rhythmicity, in
C3H/He mice. Zeitgeber time (ZT) was assessed with reference to the onset of light period
(ZT0). Exposure to fluorescent light (70 lux) for 1 h in the dark period (ZT14) caused a
significant increase in hepatic Pai-1 gene expression at ZT16. Serum
PAI-1 levels also tended to increase, albeit not significantly. Expression levels of the
typical clock genes Bmal1, Clock, and
Per1 were significantly increased at ZT21, ZT16, and ZT18,
respectively. Exposure to nocturnal light significantly increased plasma adrenalin levels.
The effects of nocturnal light exposure on Pai-1 expression disappeared
in adrenalectomized mice, although the changes in clock genes were still apparent. In
conclusion, our results suggest that nocturnal light exposure, even for 1 h, alters
hepatic Pai-1 gene expression by stimulating the adrenal pathway.
Adrenalin secreted from the adrenal gland may be an important signaling mediator of the
change in Pai-1 expression in response to nocturnal light exposure. 相似文献
992.
Valentina Danesi Lorenzo Zani Axel Scheele Francesco Berra Luca Cristofolini 《Journal of biomechanics》2014
Definition of an anatomical reference frame is necessary for in vitro biomechanical testing. Nevertheless, there is neither a clear recommendation, nor consensus in the literature concerning an anatomical reference frame for in vitro testing of the human vertebrae. The scope of this work is to define a reference frame for the human vertebrae for in vitro applications. The proposed anatomical reference frame relies on alignment of well-defined points on the endplates, and on two landmarks on the posterior wall. The repeatability of the proposed alignment procedure has been tested in vitro by 5 operators, on 7 specimens. Furthermore, the feasibility and repeatability of the proposed procedure was assessed in silico, using CT-scans of the same specimens. 相似文献
993.
Jérôme Coupier Fédor MoiseevVéronique Feipel Marcel RoozeSerge Van Sint Jan 《Journal of biomechanics》2014
Despite the availability of the International Society of Biomechanics (ISB) recommendations for the orientation of anatomical frames, no consensus exists about motion representations related to finger kinematics. This paper proposes novel anatomical frames for motion representation of the phalangeal segments of the long fingers. A three-dimensional model of a human forefinger was acquired from a non-pathological fresh-frozen hand. Medical imaging was used to collect phalangeal discrete positions. Data processing was performed using a customized software interface (“lhpFusionBox”) to create a specimen-specific model and to reconstruct the discrete motion path. Five examiners virtually palpated two sets of landmarks. These markers were then used to build anatomical frames following two methods: a reference method following ISB recommendations and a newly-developed method based on the mean helical axis (HA). Motion representations were obtained and compared between examiners. Virtual palpation precision was around 1 mm, which is comparable to results from the literature. The comparison of the two methods showed that the helical axis method seemed more reproducible between examiners especially for secondary, or accessory, motions. Computed Root Mean Square distances comparing methods showed that the ISB method displayed a variability 10 times higher than the HA method. The HA method seems to be suitable for finger motion representation using discrete positions from medical imaging. Further investigations are required before being able to use the methodology with continuous tracking of markers set on the subject?s hand. 相似文献
994.
Hester Vlaardingerbroek Kenneth Ng Barbara Stoll Nancy Benight Shaji Chacko Leo A. J. Kluijtmans Wim Kulik E. James Squires Oluyinka Olutoye Deborah Schady Milton L. Finegold Johannes B. van Goudoever Douglas G. Burrin 《Journal of lipid research》2014,55(3):466-477
Total parenteral nutrition (TPN) is associated with the development of parenteral nutrition-associated liver disease (PNALD) in infants. Fish oil-based lipid emulsions can reverse PNALD, yet it is unknown if they can prevent PNALD. We studied preterm pigs administered TPN for 14 days with either 100% soybean oil (IL), 100% fish oil (OV), or a mixture of soybean oil, medium chain triglycerides (MCTs), olive oil, and fish oil (SL); a group was fed formula enterally (ENT). In TPN-fed pigs, serum direct bilirubin, gamma glutamyl transferase (GGT), and plasma bile acids increased after the 14 day treatment but were highest in IL pigs. All TPN pigs had suppressed hepatic expression of farnesoid X receptor (FXR), cholesterol 7-hydroxylase (CYP7A1), and plasma 7α-hydroxy-4-cholesten-3-one (C4) concentrations, yet hepatic CYP7A1 protein abundance was increased only in the IL versus ENT group. Organic solute transporter alpha (OSTα) gene expression was the highest in the IL group and paralleled plasma bile acid levels. In cultured hepatocytes, bile acid-induced bile salt export pump (BSEP) expression was inhibited by phytosterol treatment. We show that TPN-fed pigs given soybean oil developed cholestasis and steatosis that was prevented with both OV and SL emulsions. Due to the presence of phytosterols in the SL emulsion, the differences in cholestasis and liver injury among lipid emulsion groups in vivo were weakly correlated with plasma and hepatic phytosterol content. 相似文献
995.
Magda M. El-Mahdi Wafaa A. Mansour Olfat Hammam Noha A. Mehana Taghreed M. Hussein 《The Korean journal of parasitology》2014,52(2):151-162
The technique of stem cells or hepatocytes transplantation has recently improved in order to bridge the time before whole-organ liver transplantation. In the present study, unfractionated bone marrow stem cells (BMSCs) were harvested from the tibial and femoral marrow compartments of male mice, which were cultured in Dulbecco''s modified Eagle''s medium (DMEM) with and without hepatocyte growth factor (HGF), and then transplanted into Schistosoma mansoni-infected female mice on their 8th week post-infection. Mice were sacrificed monthly until the third month of bone marrow transplantation, serum was collected, and albumin concentration, ALT, AST, and alkaline phosphatase (ALP) activities were assayed. On the other hand, immunohistopathological and immunohistochemical changes of granuloma size and number, collagen content, and cells expressing OV-6 were detected for identification of liver fibrosis. BMSCs were shown to differentiate into hepatocyte-like cells. Serum ALT, AST, and ALP were markedly reduced in the group of mice treated with BMSCs than in the untreated control group. Also, granuloma showed a marked decrease in size and number as compared to the BMSCs untreated group. Collagen content showed marked decrease after the third month of treatment with BMSCs. On the other hand, the expression of OV-6 increased detecting the presence of newly formed hepatocytes after BMSCs treatment. BMSCs with or without HGF infusion significantly enhanced hepatic regeneration in S. mansoni-induced fibrotic liver model and have pathologic and immunohistopathologic therapeutic effects. Also, this new therapeutic trend could generate new hepatocytes to improve the overall liver functions. 相似文献
996.
Daniel M. Kelly Joanne E. Nettleship Samia Akhtar Vakkat Muraleedharan Donna J. Sellers Jonathan C. Brooke David S. McLaren Kevin S. Channer T. Hugh Jones 《Life sciences》2014
Aims
Non-alcoholic fatty liver disease and its precursor hepatic steatosis is common in obesity and type-2 diabetes and is associated with cardiovascular disease (CVD). Men with type-2 diabetes and/or CVD have a high prevalence of testosterone deficiency. Testosterone replacement improves key cardiovascular risk factors. The effects of testosterone on hepatic steatosis are not fully understood.Main methods
Testicular feminised (Tfm) mice, which have a non-functional androgen receptor (AR) and very low serum testosterone levels, were used to investigate testosterone effects on high-cholesterol diet-induced hepatic steatosis.Key findings
Hepatic lipid deposition was increased in Tfm mice and orchidectomised wild-type littermates versus intact wild-type littermate controls with normal androgen physiology. Lipid deposition was reduced in Tfm mice receiving testosterone treatment compared to placebo. Oestrogen receptor blockade significantly, but only partially, reduced the beneficial effects of testosterone treatment on hepatic lipid accumulation. Expression of key regulatory enzymes of fatty acid synthesis, acetyl-CoA carboxylase alpha (ACACA) and fatty acid synthase (FASN) were elevated in placebo-treated Tfm mice versus placebo-treated littermates and Tfm mice receiving testosterone treatment. Tfm mice on normal diet had increased lipid accumulation compared to littermates but significantly less than cholesterol-fed Tfm mice and demonstrated increased gene expression of hormone sensitive lipase, stearyl-CoA desaturase-1 and peroxisome proliferator-activated receptor-gamma but FASN and ACACA were not altered.Significance
An action of testosterone on hepatic lipid deposition which is independent of the classic AR is implicated. Testosterone may act in part via an effect on the key regulatory lipogenic enzymes to protect against hepatic steatosis. 相似文献997.
998.
Oytun Erbaş Volkan Solmaz Dürdane Aksoy Altuğ Yavaşoğlu Mustafa Sağcan Dilek Taşkıran 《Life sciences》2014
Aim
The aim of this study was to examine the effects of cholecalciferol on systemic inflammation and memory in the setting of fatty liver disease in rats.Materials and methods
To induce the development of fatty liver disease, the rats were fed a 35% fructose solution over 8 weeks. Group I (n = 6) was designated as the control group and fed with standard rat chow. Group II (n = 6) was provided with, standard rat chow, and 0.3 μg/kg/day of oral cholecalciferol over a duration of 2 weeks. In addition to standard rat chow, group III (n = 6) and group IV (n = 6) were given 4 mL of the 35% fructose solution per day via oral gavage for 8 weeks. However, group IV was also given 0.3 μg/kg/day of oral cholecalciferol over 2 weeks. After the treatment period, passive avoidance tasks were performed by all groups. The liver and brain were harvested for subsequent biochemical and histopathologic analyses.Key findings
The development of fatty liver extends the memory latency period of passively avoiding tasks after 1 trial. Moreover, there were increases in brain TNF-α and plasma MDA levels according to two-way analysis of variance. Cholecalciferol supplementation decreased the latency period of passively avoiding tasks in rats with hepatosteatosis, and also significantly reduced brain TNF-α and plasma MDA levels.Significance
Fatty liver may contribute to the development of systemic inflammation, which affects cognition and causes deficits in memory; however, the anti-inflammatory and antioxidant properties of vitamin D may improve the cognitive function of rats with hepatosteatosis. 相似文献1000.