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61.
作者于2005年2月从广东省湛江市硇洲岛一位渔民手中采集到一块鲸类的脊椎骨,据渔民对该搁浅鲸类的外形描述推断该骨骼属于一种大型须鲸.为了鉴定该脊椎骨所属的种类,本文利用分子生物学技术,从中提取基因组DNA,并以此为模板特异性扩增Cyt b基因的部分序列进行物种鉴定.  相似文献   
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The dietary polyphenolic compound resveratrol, by activating the protein deacetylase enzyme silent information regulator 2/sirtuin 1 (SIRT1), prolongs life span in evolutionarily distant organisms and may mimic the cytoprotective effects of dietary restriction. The present study was designed to elucidate the effects of resveratrol on cigarette smoke-induced vascular oxidative stress and inflammation, which is a clinically highly relevant model of accelerated vascular aging. Cigarette smoke exposure of rats impaired the acetylcholine-induced relaxation of carotid arteries, which could be prevented by resveratrol treatment. Smoking and in vitro treatment with cigarette smoke extract (CSE) increased reactive oxygen species production in rat arteries and cultured coronary arterial endothelial cells (CAECs), respectively, which was attenuated by resveratrol treatment. The smoking-induced upregulation of inflammatory markers (ICAM-1, inducible nitric oxide synthase, IL-6, and TNF-alpha) in rat arteries was also abrogated by resveratrol treatment. Resveratrol also inhibited CSE-induced NF-kappaB activation and inflammatory gene expression in CAECs. In CAECs, the aforementioned protective effects of resveratrol were abolished by knockdown of SIRT1, whereas the overexpression of SIRT1 mimicked the effects of resveratrol. Resveratrol treatment of rats protected aortic endothelial cells against cigarette smoking-induced apoptotic cell death. Resveratrol also exerted antiapoptotic effects in CSE-treated CAECs, which could be abrogated by knockdown of SIRT1. Resveratrol treatment also attenuated CSE-induced DNA damage in CAECs (comet assay). Thus resveratrol and SIRT1 exert antioxidant, anti-inflammatory, and antiapoptotic effects, which protect the endothelial cells against the adverse effects of cigarette smoking-induced oxidative stress. The vasoprotective effects of resveratrol will likely contribute to its antiaging action in mammals and may be especially beneficial in pathophysiological conditions associated with accelerated vascular aging.  相似文献   
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Fenneropenaeus chinensis is distributed along the coasts of the northern seacoast of China and the Korean Peninsula. According to their migration routes, spawning and overwintering places, F. chinensis is divided mainly into three geographic variety populations. These populations represent potentially different genetic resources important to hybridisation breeding programs. To evaluate heterosis of the total protein concentration (PC), haemocyanin concentration (HC), penoloxidase (PO) activity, acid phosphatase (ACP) activity, alkaline phosphatase (ALP) activity and antimicrobial activity (Ua) mating was produced between and within Yellow and Bo sea (YB) population and southern seacoast of Korean Peninsula (SK) population, and the offspring of 49 families was reared to 7.64 g in the controlled environment. The results showed that the content of all haemolymph analytes of SK population was higher than that of YB population, and the immunocompetence in all hybridisations were higher than that in YB male x YB female except of HC in YB male x SK female. Nine of 12 hybridisations had manifested positive heterosis in six haemolymph analytes. Heterosis of SK x YB was all-positive, and this hybridisation was better than YB x SK in HC, PO, ALP activity and Ua. The results suggested that the haemolymph analytes of YB and SK populations had many genetic differences, and hybridisation was an important tool to increase immune reaction and adverse resistance.  相似文献   
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Type 2 diabetes (T2D) is a leading risk factor for a variety of cardiovascular diseases including coronary heart disease and atherosclerosis. Exercise training (ET) has a beneficial effect on these disorders, but the basis for this effect is not fully understood. This study was designed to investigate whether the ET abates endothelial dysfunction in the aorta in T2D. Heterozygous controls (m Lepr(db)) and type 2 diabetic mice (db/db; Lepr(db)) were either exercise entrained by forced treadmill exercise or remained sedentary for 10 wk. Ex vivo functional assessment of aortic rings showed that ET restored acetylcholine-induced endothelial-dependent vasodilation of diabetic mice. Although the protein expression of endothelial nitric oxide synthase did not increase, ET reduced both IFN-γ and superoxide production by inhibiting gp91(phox) protein levels. In addition, ET increased the expression of adiponectin (APN) and the antioxidant enzyme, SOD-1. To investigate whether these beneficial effects of ET are APN dependent, we used adiponectin knockout (APNKO) mice. Indeed, impaired endothelial-dependent vasodilation occurred in APNKO mice, suggesting that APN plays a central role in prevention of endothelial dysfunction. APNKO mice also showed increased protein expression of IFN-γ, gp91(phox), and nitrotyrosine but protein expression of SOD-1 and -3 were comparable between wild-type and APNKO. These findings in the aorta imply that APN suppresses inflammation and oxidative stress in the aorta, but not SOD-1 and -3. Thus ET improves endothelial function in the aorta in T2D via both APN-dependent and independent pathways. This improvement is due to the effects of ET in inhibiting inflammation and oxidative stress (APN-dependent) as well as in improving antioxidant enzyme (APN-independent) performance in T2D.  相似文献   
68.
A series of 4-aryl-cyclopenta[b]pyran derivatives, designed based on natural product scaffold, were synthesized efficiently via multi-component reaction under solvent-free and catalyst-free conditions. This chemistry provides a new compound library with potential activity for biomedical screening.  相似文献   
69.
S Zou  F Wu  C Guo  J Song  C Huang  Z Zhu  H Yu  Y Guo  X Lu  Y Ruan 《PloS one》2012,7(7):e40718

Background

Both insufficient and excess iodine may produce thyroid disease. After salt iodization in China, the median urine iodine concentration (UIC) of children aged 8–10 years appeared adequate. However, it is unknown whether dietary changes due to rapid economic development in Shanghai have affected whole population iodine nutrition.

Objective

To assess dietary iodine intake, UIC and the prevalence of thyroid disease in the general population of Shanghai.

Design

A cross-sectional survey was conducted with general participants aged 5–69 years (n = 7,904) plus pregnant and lactating women (n = 380 each) selected by stratified multistage sampling. The iodine concentrations in their salt, drinking water and urine were measured. Daily iodine intake was estimated using the total diet study approach. Serum thyroid hormone concentrations and thyroid-related antibodies were measured and thyroid ultrasonography was performed.

Results

The median iodine concentration in salt was 29.5 mg/kg, and 12.8 µg/L in drinking water. Iodized salt, used by 95.3% of participants, contributed 63.5% of total dietary iodine. Estimated daily iodine intake was 225.96 µg. The median UIC of general participants was 146.7 µg/L; UIC <100 µg/L (iodine insufficiency) was seen in 28.6%; UIC >300 µg/L (iodine excess) in 10.1%. Pregnant women had a median UIC of 135.9 µg/L, with UIC <150 µg/L in 55.4%. Thyroid nodules and subclinical hypothyroidism were found in 27.44% and 9.17%, respectively.

Conclusions

According to published criteria, the current dietary iodine intake in Shanghai was generally sufficient and safe, but insufficient in pregnant women. Thyroid nodules and subclinical hypothyroidism were the commonest thyroid diseases identified.  相似文献   
70.
Adiponectin (APN) can confer protection against metabolism-related illnesses in organs such as fat, the liver, and skeletal muscle. However, it is unclear whether APN improves endothelial-dependent nitric oxide-mediated vasodilation in type 2 diabetes and, if so, by what mechanism. We tested whether exogenous APN delivery improves endothelial function in type 2 diabetic mice and explored the mechanisms underlying the observed improvement. To test the hypothesis, we injected adenovirus APN (Ad-APN) or adenovirus β-galactosidase (Ad-βgal; control virus) via the tail vein in control (m Lepr(db)) and diabetic (Lepr(db); db/db) mice and studied vascular function of the aorta ex vivo. Ad-APN improved endothelial-dependent vasodilation in db/db mice compared with Ad-βgal, whereas Ad-APN had no further improvement on endothelial function in control mice. This improvement was completely inhibited by a nitric oxide synthase inhibitor (N(G)-nitro-l-arginine methyl ester). Serum triglyceride and total cholesterol levels were increased in db/db mice, and Ad-APN significantly reduced triglyceride levels but not total cholesterol levels. Immunoblot results showed that interferon-γ, gp91(phox), and nitrotyrosine were markedly increased in the aorta of db/db mice. Ad-APN treatment decreased the expression of these proteins. In addition, mRNA expression of TNF-α, IL-6, and ICAM-1 was elevated in db/db mice, and Ad-APN treatment decreased these expressions in the aorta. Our findings suggest that APN may contribute to an increase in nitric oxide bioavailability by decreasing superoxide production as well as by inhibiting inflammation and adhesion molecules in the aorta in type 2 diabetic mice.  相似文献   
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