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1.
浒苔多糖的分离、纯化和分析   总被引:1,自引:0,他引:1  
浒苔(Enteromorphaprolifera)经热水提取,Sevage法除去蛋白质,用乙醇沉淀,SephadexG-100柱层析,得浒苔多糖(简称EP)精制品。经SephadexG-200柱层析鉴定为单一对称性洗脱峰。红外光谱分析具有多糖特征吸收峰,紫外光谱分析未见有核酸和蛋白质的特征吸收峰。总糖含量为88.8%,其中糖醛酸含量为33.6%。单糖组成为L-阿拉伯糖、L-岩藻糖、D-甘露糖、D-半乳糖及D-葡萄糖,平均分子量为25000。  相似文献   
2.
浒苔多糖剂量150mg/kg可使高胆固醇血症小鼠血清胆固醇下降22%,剂量168mg/kg可使高脂血症大鼠TCH和TG分别降低58%和61%,HDL升高27%,剂量250mg/kg可分别提高血清、脑和肝SOD活力33%、118%和224%,剂量168mg/kg对高血脂大鼠血清和心脏LPO含量降低35%和46%。  相似文献   
3.
Thymidylate synthetase is the major target of 5-fluorouracil (5-FU), which is widely used for the treatment of gastric cancer (GC) and colorectal cancer (CRC). This meta-analysis aimed to elucidate the effect of Ts polymorphisms on the efficacy of 5-FU-based chemotherapy in GC and CRC patients. Individual data were analyzed from 10 studies of 1102 GC and CRC patients treated with 5-FU-based regimens. The primary outcomes of interest were overall survival (OS) and progression-free survival (PFS). Data were pooled using the program STATA version 10.0 (Stata Corporation, College Station, TX). The relationship between the Ts polymorphism and survival following 5FU-based treatment of GC and CRC patients was systematically summarized. Compared with the C allele, the G allele was associated with shorter PFS but with similar OS in Caucasian CRC patients. Compared with the 3R/3R genotype, the 2R/3R or 2R/2R genotype was associated with the same PFS, but with a shorter OS, particularly in Caucasian CRC patients. These results show a correlation between survival following 5-FU-based therapy and tumor genotype in Caucasian CRC patients. Larger studies and further clinical trials are required to confirm this observation.  相似文献   
4.
Degradation of terephthalate (TA) through microbial syntrophy under moderately thermophilic (46 to 50°C) methanogenic conditions was characterized by using a metagenomic approach (A. Lykidis et al., ISME J. 5:122–130, 2011). To further study the activities of key microorganisms responsible for the TA degradation, community analysis and shotgun proteomics were used. The results of hierarchical oligonucleotide primer extension analysis of PCR-amplified 16S rRNA genes indicated that Pelotomaculum, Methanosaeta, and Methanolinea were predominant in the TA-degrading biofilms. Metaproteomic analysis identified a total of 482 proteins and revealed a distinctive distribution pattern of microbial functions expressed in situ. The results confirmed that TA was degraded by Pelotomaculum spp. via the proposed decarboxylation and benzoyl-coenzyme A-dependent pathway. The intermediate by-products, including acetate, H2/CO2, and butyrate, were produced to support the growth of methanogens, as well as other microbial populations that could further degrade butyrate. Proteins related to energy production and conservation, and signal transduction mechanisms (that is, chemotaxis, PAS/GGDEF regulators, and stress proteins) were highly expressed, and these mechanisms were important for growth in energy-limited syntrophic ecosystems.  相似文献   
5.
Type I and II pyrethroid insecticides display different neurotoxicity. To investigate the long-term (60 days exposure) metabolic effect of the two types of pyrethroid insecticides deltamethrin and permethrin, 1H nuclear magnetic resonance (NMR) spectroscopy-based metabonomics was used to analyze the biochemical composition of urine and serum samples from rats administrated daily with deltamethrin or permethrin for 60 consecutive days, and principal component analysis used to visualize similarities and differences in the resultant biochemical profiles. Rats treated with either deltamethrin or permethrin displayed increased levels of urinary acetate, dimethylamine, dimethylglycine, trimethylamine and serum free amino acids, and decreased urinary 2-oxoglutarate, all of which are indicative of kidney lesions and nephrotoxicity. The reduced excretion of tricarboxylic acid cycle intermediates, together with increased 3-D-hydroxybutyrate, acetate, and lactate in treated rats could suggest disturbance of the energy metabolism, including an increased rate of anaerobic glycolysis, enhanced fatty acid β-oxidation and ketogenesis. These results show that these two types of insecticides have similarities in the urine and serum spectra, indicating that similar metabolic pathways are perturbed by the insecticides, which induced hepatotoxicity and nephrotoxicity. This approach may lead to the discovery of novel biomarkers of pyrethroids toxicity and thereby provide new insights into the toxicological mechanisms of pesticides pyrethroids.  相似文献   
6.
A novel halophilic, filamentous actinomycete, designated TRM 4064T, was isolated from a hypersaline habitat in Sichuan Province, China. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of strain TRM 4064T showed that it was most closely related to Actinopolyspora mortivallis (99.1 % sequence similarity). The sequence similarities between strain TRM 4064T and other Actinopolyspora species with validly-published names were <97.0 %. However, it had relatively low mean values for DNA–DNA relatedness with the A. mortivallis DSM 44261T (23.2 %). Optimal growth occurred at 37 °C, pH 7.0 and in the presence of 13 % (w/v) NaCl. The whole-cell sugar pattern consists of xylose, glucose, ribose and arabinose. The predominant menaquinones are MK-10(H4) (38.2 %), MK-9(H4) (25.1 %), MK-9(H2) (28.6 %) and MK-8(H4) (7.3 %). The major fatty acids are anteiso-C17:0 (36.9 %) and iso-C17:0 (19.3 %). The diagnostic phospholipids detected were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylcholine (PC), phosphatidylinositol (PI) and two unknown phospholipids. The G+C content of the genomic DNA of the type strain is 66.3 mol%. Strain TRM 4064T therefore represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora dayingensis sp. nov. is proposed. The type strain is TRM 4064T (= KCTC 19979T = CCTCC AA 2010010T).  相似文献   
7.

Background

Improving the health and well-being of women and children has long been a common goal throughout the world. From 2005 to 2011, Suizhou City had an annual average of 22,405 pregnant and parturient women (1.04% of the population) and 98,811 children under 5 years old (4.57% of the population). Understanding the status of maternal and child health care in Suizhou City during such period can provide the local health administrative department valid scientific bases upon which to construct effective policies.

Methods

Various types of annual reports on maternal and child health care were collected and analyzed retrospectively.

Results

Mortality rates for infants and children under 5 years showed a declining trend, while the rates of newborn home visiting, maternal health service coverage, and children health systematic management increased annually in Suizhou City from 2005 to 2011. The incidence of birth defect increased from 2.42‰ in 2005 to 3.89‰ in 2011. The maternal mortality ratio (MMR) fluctuated from 8.39/100,000 to 28.77/100,000, which was much lower than the national MMR (30.0/100,000 in 2010). The rates of hospitalized delivery and births attended by trained health personnel for pregnant women increased to more than 90% in the past five years.

Conclusions

The improvements in maternal and child health care work in Suizhou City are worthy of recognition. Thus, the government should continue to increase funding in these areas to promote the complete enhancement of the maternal and child health care system.  相似文献   
8.
为从分子水平探索不同地区伞裙追寄蝇种群间的内在联系,本文利用ISSR分子标记技术对8个不同地区伞裙追寄蝇自然种群进行遗传多样性、种群间分化程度以及聚类分析等研究。结果表明:筛选出11对多态性稳定的ISSR引物,对8个地区伞裙追寄蝇群体的80个个体进行PCR扩增,共获得166个重复性好且清晰可辨的ISSR条带,平均每条引物扩增出15.0909个片段,且均为多态性条带,多态信息含量(PIC)为0.8441-0.8653;香农信息指数(I)为0.1240-0.3455;Nei's遗传多样性指数(H)为0.0841-0.2285;基因分化率(Gst)为28.78%,基因流(Nm)的均值为1.5702,即遗传变异主要存在于个体之间,不同种群间基因交流处于中等水平;8个地区伞裙追寄蝇种群被划分为4个类群,种群间的遗传分化与地理距离呈正相关关系。  相似文献   
9.

Background

Abnormal expression of serum TGF-β1 was found in patients with diabetic nephropathy. However, the association of TGF-β1 with the risk of diabetic nephropathy remains unknown. The present study was undertaken to investigate whether such an association exists.

Methods

We searched the Chinese VIP, Wangfang, China National Knowledge Infrastructure, PubMed, Embase, and Google Scholar databases for relevant studies and extracted all eligible data. Stata12 software was used for statistical analysis.

Results

Nine reports met our criteria and were used for data extraction. There were 264 patients and 227 healthy controls from qualified reports in this meta-analysis. The results suggested that serum TGF-β1 levels were significantly up-regulated in patients with diabetic nephropathy; the instrumental variable was 3.94 (95% confidence interval 3.20–4.68, p<0.01).

Conclusions

Meta-analysis suggested that elevated serum TGF-β level in patients with diabetes is associated with a high risk of nephropathy. Further studies are required to validate these observations.  相似文献   
10.
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