食盐对普通玉米杂交种淀粉糊化性质的影响

采用快速粘度分析仪（RVA）研究了食盐对18种普通玉米杂交种淀粉糊化性质的影响。结果表明：食盐显著降低了所有普通玉米杂交种淀粉的峰值、破损值和回生值;提高了谷值、终粘度、出峰时间和成糊温度。但对不同的普通玉米杂交种淀粉的糊化性质的影响程度有显著差别。随着食盐溶液质量分数的增加,普通玉米杂交种淀粉的谷值、终粘度、出峰时间和成糊温度也逐渐增加,破损值和回生值则显著降低,峰值受食盐溶液质量分数的影响很小。     

纤维素酶对玉米秸青贮营养成分及其奶牛瘤胃降解率的影响

本研究探讨了添加纤维素酶制剂对玉米秸青贮营养成分含量变化及其瘤胃内降解率的影响。以去穗玉米秸为试验材料,分别以0.00 g/1kg(C)、0.05g/1kg(Ⅰ)、0.2g/1kg(Ⅱ)、1g/1kg(Ⅲ)进行添加纤维素酶,贮藏4周后进行常规营养成分含量变化分析和饲养试验。用4头装有永久性瘘管荷斯坦乳牛,按4×4拉丁方设计进行瘤胃内降解率的试验。结果为:Ⅰ组、Ⅱ组和Ⅲ组玉米秸青贮DM含量差异不显著,但均显著低于C组;不同处理组的玉米秸青贮CP含量随纤维素添加量增加而显著提高,以1g/1kg纤维素酶添加处理的提高幅度最大;NDF和ADF含量均随着纤维素添加量增加而显著下降,其中1g/1kg纤维素酶添加处理的下降幅度最大。Ⅲ组、Ⅱ组和Ⅰ组玉米秸青贮的DM和CP奶牛瘤胃有效降解率均显著高于C组,并且Ⅲ组显著高于Ⅱ组和Ⅰ组;不同处理组的玉米秸青贮NDF有效降解率之间差异显著,Ⅲ组>Ⅱ组>Ⅰ组>C组;玉米秸青贮ADF有效降解率Ⅲ组、Ⅱ组和Ⅰ组之间无显著差异,但均显著高于C组。表明纤维素酶处理能提高青贮营养价值,且纤维素酶以1g/1kg添加量为宜。     

Pituitary stalk meningioma: case report

We report a 45-year-old woman with a meningioma which was in contact with only the pituitary stalk on MRI. As the pituitary stalk has no dura mater, we suggest this tumour may have originated from the arachnoid membrane of the pituitary stalk. Though some reports have shown that meningiomas can arise from sites lacking a dural component, this is the first report of a meningioma originating from the pituitary stalk. Received: 21 December 1995 Accepted: 26 February 1996     

药用淀粉生产工艺改进研究

用十二烷基硫酸钠或十二烷基磺酸钠与亚硫酸的混合液浸泡玉米，能有效地降低玉米淀粉中的蛋白质含量，较单独用亚硫酸浸泡，所得玉米淀粉的蛋白质含量可分别降低４０％和３５％。     

Inhibition of IgE formation in mice by glycoproteins from corn silk

The inhibitory effects of glycoproteins separated from a hot water extract of corn silk (U-CSE) on the formation of IgE antibodies after primarily and secondarily challenged responses with dinitrophenyl (DNP)-ovalbumin (OVA) antigen in mice were investigated using the passive cutaneous anaphylaxis (PCA) test. When U-CSE was given intranasally or intraperitoneally the day before primary immunization, IgE antibody production was strongly inhibited. Furthermore, it was found that new formation of IgE antibodies was readily inhibited by U-CSE administration in mice with high levels of IgE after primary immunization. It was also found that U-CSE markedly suppressed IgE antibody formation in secondarily challenged responses with the antigen. U-CSE may be clinically applicable to type I allergic diseases.     

Safety assessment of high fructose corn syrup (HFCS) as an ingredient added to cigarette tobacco

A tiered testing strategy has been developed to evaluate the potential for new ingredients, tobacco processes, and technological developments to alter the biological activity that results from burning tobacco. A series of studies was initially conducted with cigarettes containing 3% high fructose corn syrup (HFCS) as an alternate tobacco casing material to corn syrup/invert sugar, including determination of selected mainstream cigarette smoke (MS) constituent yields, Ames assay, sister chromatid exchange (SCE) assay in Chinese hamster ovary (CHO) cells, a 30-week dermal tumor-promotion evaluation of cigarette smoke condensate (CSC) in SENCAR mice, and a 13-week subchronic inhalation study of MS in Sprague-Dawley rats. A second series of studies was conducted with cigarettes containing 3%, 4% and 5% HFCS including MS chemistry, Ames assay, SCE assay in CHO cells, and a neutral red cytotoxicity assays. Collectively, mainstream smoke chemistry, genotoxicity, dermal tumor-promotion, and inhalation toxicity studies demonstrated no differences between cigarettes with 3% HFCS and cigarettes with 3% corn syrup/invert sugar. Also, mainstream smoke chemistry and genotoxicity of cigarettes with 4% and 5% HFCS were not different from cigarettes with 3% HFCS. In conclusion, the addition of up to 5% HFCS to cigarette does not alter the mainstream smoke chemistry or biological activity of mainstream smoke or mainstream smoke condensate as compared to cigarettes with 3% corn syrup/invert sugar with regard to the parameters investigated and presented.     

Supradiaphragmatic ectopic adrenocorticotropic hormone-secreting adenoma

A 22-year-old woman with Cushing's syndrome, caused by an extremely rare suprasellar ectopic pituitary adenoma, is presented. Magnetic resonance imaging and computed tomography revealed a well-circumscribed mass in the right suprasellar region. Endocrinological tests showed elevated s-adrenocorticotropic hormone level and hypercortisolemia. The tumor was totally removed by right subfrontal approach. At the time of the operation, the tumor was in continuity with the distal pituitary stalk but not with the pituitary gland. The diaphragma sellae was intact. Histologic diagnosis of the tumor specimen was confirmed as a pituitary adenoma. After surgical removal of the tumor, continued improvement in the patient's laboratory results and disappearance of her endocrine symptoms strongly indicated the absence of adenoma cells in the pituitary gland or stalk. Six years post-surgery, there was no evidence of recurrence in the patient's clinical and laboratory examination. This tumor probably originated from aberrant anterior pituitary cells of the pituitary stalk.     

酸性核糖体磷酸化蛋白P(0-2)的研究进展

酸性核糖体磷酸化蛋白P0、P1、P2是位于真核生物核糖体60S大亚基上的三种核糖体磷酸化蛋白,它们在核糖体上共同组成一个独特的向外侧凸出的五聚体复合物核糖体茎区,此茎区与核糖体上的28 SrRNA的一个保守结构域共同形成一个GTPase相关位点,并在蛋白质翻译延伸过程起着重要的作用。此外,酸性核糖体磷酸化蛋白P0、P1、P2还与细胞凋亡、肿瘤和免疫性疾病的发生、发展密切相关。本文就这三个蛋白结构、功能及其相关作用机制作一综述。     

Protein‐energy intakes in a malnourished population after increasing the supply of the dietary staples

This paper examines the extent to which food intake in malnourished populations is affected by increasing the availability of the dietary staples. Free amounts of corn and beans were supplied to 47 families in a rural Guatemalan community during eight weeks. Relative to a six‐week baseline period, adults increased their intakes by about 400 kcal (1.68 MJ) and 15 gof protein per day. The average changes for pre‐school children were 198 kcl (0.83 MJ) and 5.8 g of protein per day. The findings suggest that it is possible for adults to satisfy their energy and protein needs by consuming more corn and beans. In children, bulk may be a limiting factor and it may be necessary to resort to additional measures, such as increasing the energy density of the diet, to satisfy needs.     

High fructose corn syrup and diabetes prevalence: A global perspective

Abstract

The overall aim of this study was to evaluate, from a global and ecological perspective, the relationships between availability of high fructose corn syrup (HFCS) and prevalence of type 2 diabetes. Using published resources, country-level estimates (n =43 countries) were obtained for: total sugar, HFCS and total calorie availability, obesity, two separate prevalence estimates for diabetes, prevalence estimate for impaired glucose tolerance and fasting plasma glucose. Pearson's correlations and partial correlations were conducted in order to explore associations between dietary availability and obesity and diabetes prevalence. Diabetes prevalence was 20% higher in countries with higher availability of HFCS compared to countries with low availability, and these differences were retained or strengthened after adjusting for country-level estimates of body mass index (BMI), population and gross domestic product (adjusted diabetes prevalence=8.0 vs. 6.7%, p=0.03; fasting plasma glucose=5.34 vs. 5.22 mmol/L, p=0.03) despite similarities in obesity and total sugar and calorie availability. These results suggest that countries with higher availability of HFCS have a higher prevalence of type 2 diabetes independent of obesity.