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青岛近海及其临近海域冬季微微型浮游植物的分布   总被引:2,自引:0,他引:2  
微微型浮游植物(0.2~2.0 μm) 是海水中最小的自养浮游生物, 在世界各海域广泛分布, 并在海洋有机物质循环中起着非常重要的作用.利用荧光显微技术对青岛近海及其邻近海域冬季微微型浮游植物丰度进行了调查,研究了微微型浮游植物的空间变化和昼夜变化的特征, 并分析了微微型浮游植物丰度与环境因子的相关性. 结果显示, 冬季该海域以富含藻红素(Phycoerythrin-rich, PE)的聚球藻(Synechococcus, Syn)细胞占优势,微微型真核藻类(Picoeukaryote, Euk)次之,而富含藻蓝素(Phycocyanin-rich, PC)的聚球藻细胞数量很低, 未发现原绿球藻(Prochlorococcus, Pro)的存在.Syn 的变化范围为8.97×103~1.95×105 cells·ml-1, 平均4.67×104 cells·ml-1; Euk的变化范围为1.95×102~1.01×104 cells·ml-1, 平均2.39×103 cells·ml-1. Syn丰度在胶南以南海域出现高值区域, 在即墨海域和崂山东南海域出现低值区域. Euk丰度在日照海域出现高值区域; 崂山海域为低值区域; 各水层Syn和Euk丰度均无明显差异(P﹥0.05). 对胶州湾中部连续站4层水体的24 h昼夜连续变化进行观测发现, Syn、Euk丰度都有明显昼夜波动.相关性分析表明: Syn与温度、 电导率呈正相关, 与溶氧浓度呈显著负相关; Euk与盐度和溶氧浓度呈显著负相关. 微微型浮游植物对总浮游植物生物量的贡献约为20%.  相似文献   
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为了研究重组CHO细胞乙肝表面抗原(CHO-rHBsAg)在小鼠中诱导T细胞免疫应答的能力,全面评价疫苗的免疫原性,以CHO-rHBsAg免疫BALB/c小鼠,常规制备小鼠脾脏淋巴细胞并在体外以抗原或特异多肽刺激;采用ELISA法测定抗原特异性T淋巴细胞分泌的细胞因子,乳酸脱氢酶法(LDH)测定抗原特异性细胞毒T淋巴细胞(CTL)活性,酶联斑点法(ELISPOT)测定CTL频数(CTLp),应用流式细胞仪分析T淋巴细胞亚群。结果显示,rHBsAg可在小鼠中诱导Th1及Th2类细胞因子;加铝佐剂的rHBsAg较未加佐剂的抗原可诱导较高水平的IFN-γ、CTL克隆及较高百分比的CD8+T淋巴细胞亚群。重组CHO细胞来源的HBsAg可在BALB/c小鼠中诱导一定程度的细胞免疫应答。  相似文献   
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Initial studies have revealed subtle differences in the T cell proliferative response to whole SIV antigen in the peripheral blood mononuclear cells (PBMC) from sooty mangabeys and rhesus macaques. Preliminary findings utilizing the cellular Western blot assay are described.  相似文献   
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PurposeWe aimed to evaluate the association between iron deficiency without anemia (IDNA) and serum lipid profiles in young women of around 20 years of age.MethodsThis study included non-anemic (hemoglobin ≥ 12 g/dL) female volunteers aged 18 to 22 years who were not taking mineral/vitamin supplements and living in the metropolitan area of Tokyo, Japan. These volunteers were classified into two groups based on their sFer (serum ferritin) levels: normal group (sFer ≥ 20 ng/mL, n = 36) and IDNA group (sFer < 20 ng/mL, n = 29). Venous blood samples were obtained from the antecubital veins of these volunteers after 10–12-h fasting to measure the hematological and biochemical parameters, including lipid levels and iron status. The results of each group were compared using Student’s t-test or the Mann–Whitney U test (for inhomogeneous variance).ResultsThe serum cholesterol levels varied depending on the iron status in the women. Serum high-density lipoprotein cholesterol (HDL-C) levels in the IDNA group were significantly higher (P = 0.006) than that in the normal group. However, the levels of total cholesterol (T-CHO), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were not significantly different between the groups. Serum LDL-C levels were positively and significantly correlated with sFer levels in the IDNA group (Kendall’s rank correlation 0.264, P = 0.044), but not in the normal group. The sFer level was not correlated with serum HDL-C in both groups. The reason for the high serum HDL-C levels in young women with IDNA is not yet clear. Compared to the normal group, the frequency of eating bread containing bran was significantly higher (P = 0.031) and that for yogurt was significantly lower (P = 0.040) in the IDNA group. The proportion of the women who were susceptible to infection, which was measured using the Cornell Medical Index, was significantly higher in the IDNA group than in the normal group. Among those susceptible to infection, the serum HDL-C level of the volunteers in the IDNA group was significantly higher than that of the volunteers in the normal group (P = 0.024).ConclusionsOur findings suggest that lipid parameters may be associated with IDNA and susceptibility to infection. Further research is needed to elucidate the mechanisms underlying the changes in the serum cholesterol levels in individuals with IDNA and the clinical significance of these findings.  相似文献   
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染色质高级结构是基因转录调节的重要因素,染色质多重相互作用是高级结构中的一种,是多个(≥3)染色质片段在空间上相互接触而形成的紧凑结构。为了解染色质多重相互作用这类高级结构的特征及其在干细胞中分化中起到的作用,通过对Hi-C数据进行相关分析并计算基因的FPKM表达量,研究了染色质多重相互作用。分析发现:多重相互作用约占所有作用的30%,包含近70%的基因;此类作用区域的高表达基因多于低表达基因;且与组蛋白乙酰化相关性高。在分化过程中,多重作用位点数目和比例减少;位于多重作用区域的基因的表达略有降低;组蛋白乙酰化(H3K27ac和H3K23ac)在多重作用区域的减弱,而组蛋白甲基化(H3K4me3和H3K27me3)倾向于增强。结果表明,染色质多重相互作用是一种广泛存在的染色质高级结构,在干细胞分化中有重要作用,此类结构多具有H3K27ac修饰,调节基因的表达。总之,染色质多重相互作用是一种重要的基因转录调节因素,在细胞分化中具有调控作用。  相似文献   
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Previous studies on Leishmania infantum and the canine immune response are derived mainly from short-term studies. To date, there have been no longitudinal studies that perform a serial analysis of the intensity of infection in conjunction with immunological parameters and clinical signs in Leishmania-infected dogs. For this purpose, six dogs were infected experimentally by the i.v. route and were monitored for 1 year. Clinical, immunological (humoral and cellular response) and parasitological (parasitaemia) parameters were evaluated monthly. Four dogs developed clinico-pathological signs compatible with leishmaniasis, whereas two dogs showed few abnormalities during the study. Evaluation of clinical, immunological and parasitological parameters showed that the intensity of Leishmania infection in blood samples, as indicated by the amount of Leishmania DNA, was correlated significantly with IgG, IgG1, IgG2, IgA, and IgM concentrations and with clinical signs. Parasitaemia and Leishmania-specific cell-mediated immunity were inversely correlated. Moreover, higher quantities of Leishmania DNA were detected in the liver, spleen, lymph node, skin and bone marrow of dogs exhibiting clinical signs than those exhibiting few such signs. These findings suggest that progressive disease in experimental canine leishmaniasis is associated with specific T-cell unresponsiveness and unprotective humoral responses which allow the dissemination and multiplication of L. infantum in different tissues.  相似文献   
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目的 建立主诊医师负责制下的住院绩效分配新模式,以适应医药分开改革的新要求。方法 探索基于医疗成果产出的岗位绩效管理考核和分配新制度,重点激励各主诊医师组医疗产出的工作量和工作难度,促使各主诊医师组增加服务量、提高技术水平和诊治疾病的难度。结果 以某科室各主诊医师组为例,从科室管理、团队建设、学科发展、工作效率等角度分析医改前后转变。结论 重点激励分配制度,逐步被医务人员所接受,并取得较为明显的成效。  相似文献   
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We have formatted an assay to detect Mycobacterium tuberculosis complex infections of non‐human primates. Commercially available reagents were used to elicit a specific immune response that was measured by interferon‐gamma release. Initial evaluation using blood samples from Rhesus macaques experimentally infected with M tuberculosis distinguished infected versus uninfected animals.  相似文献   
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To investigate effects of Zn supplementation on performance, mineral balance and immune response, 15 male crossbred cattle (Bos indicus×Bos taurus) bulls of about 14 ± 0.4 months of age and weighing 226.0 ± 9.1 kg were divided in to three groups of five. Bulls in the control group were fed wheat straw and a concentrate mixture (basal diet with 32.5 mg Zn/kg dry matter (DM)), and in ZnSO4 and ZnProp groups 35 mg Zn/kg DM was added through Zn sulphate and Zn propionate, respectively. All bulls were fed their respective treatment diets for 180 days. Daily feed intake was recorded and bulls were weighed at every 15 days to determine change in body weight (BW). After 120 days of feeding, bulls were vaccinated with Brucella abortus strain 19, and cell mediated and humoral immune responses were assessed between 120 and 148 days of experimental feeding. After 150 days of feeding, a metabolism study of 6 days duration was completed to determine nutrient digestibility and mineral balances (i.e., Ca, P, Zn, Cu, Fe and Mn). Intake of total DM, digestibility of DM, crude protein, ether extract, neutral detergent fibre and acid detergent fibre, N balance, average daily gain, feed: gain did not differ between the groups. Intake, excretion and balance of Ca, P, Zn, Cu, Fe and Mn also did not differ between the groups. However, retention of Zn was higher (P<0.001) in the ZnProp group. Bulls supplemented with Zn propionate had higher cell mediated (P<0.01) and humoral (P<0.05) immune response, while there was no alteration in immune response due to Zn sulphate supplementation. Results indicate that a diet containing about 32.5 mg Zn/kg DM was adequate to support normal growth and digestibility, but a better immune response occurred when Zn propionate was added to the diet at 35 mg/kg DM versus Zn sulphate.  相似文献   
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