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11.
介绍了一种从谷朊粉废水中提取戊聚糖的工艺,由此工艺得到的产品(戊聚糖质量分数约70%,蛋白质质量分数约20%)能较好地保持戊聚糖的特性.研究了其它添加剂(卡拉胶)对戊聚糖的乳化性,戊聚糖对肉制品持油、持水性以及其质构的影响.谷朊粉废弃水提取物与卡拉胶的复配产品在添加量(质量分数)为6%时能使肉制品有较好的持油性和相应的质构.  相似文献   
12.
Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%).  相似文献   
13.
14.
余甘子是一种具有较高的食用和药用价值的野生植物资源,风味独特,含有丰富的类SOD活性物质和其他多种具有生物活性的物质,具有清除自由基、抗肿瘤、抗衰老等保健作用。作者提出了余甘予保健口服液的生产工艺流程及配方,并采用改良的Marklund方法测定了类SOD的活力,结果较为满意。  相似文献   
15.
Common variable immunodeficiency (CVID) patients are unable to produce specific immunoglobulins after antigen contact in vivo. The aim of this study was to investigate whether in some cases of CVID a decreased de novo synthesis of IL-2 might be the cause of immunodeficiency and whether this deficiency can be corrected by IL-2 supplementation in vitro. Mononuclear cells from 17 CVID patients and from 10 healthy controls were cultured with monoclonal anti-CD3 antibody OKT3, pokeweed mitogen (PWM) or tetanus toxoid (TT) to stimulate IL-2 synthesis. In parallel, in vitro IgG and IgM synthesis was stimulated with Staphylococcus aureus Cowan I (SAC), PWM or TT in the presence or absence of IL-2. While lymphocytes of 11 out of 17 patients produced low to normal amounts of IL-2 upon stimulation with anti-CD3, only three patients showed low IL-2 production in response to PWM and five in response to TT. Regarding immunoglobulin synthesis in vitro, five patients completely failed to produce IgM or IgG upon stimulation with PWM, SAC or TT irrespective of the addition of IL-2. By contrast, four patients did not show any defect in vitro and synthesized normal amounts of IgM and IgG with any of the three stimuli. Finally, eight patients could be reconstituted for PWM-, SAC- and TT-induced IgM and/or IgG synthesis in vitro, by adding IL-2 to the culture system. This enhancing effect of IL-2 could be blocked by adding anti-IL-2 receptor antibodies to the cultures. Our findings indicate that a defective IL-2 synthesis after antigen stimulation may be one reason for the impaired immunoglobulin production in some cases of CVID.  相似文献   
16.
Background: As in many parts of the world, the Schirmer tear test is the main test used by optometrists in Saudi Arabia for assessing adequacy of tear production. Variability of the test has been reported in different ethnic groups but not in Arabs. This paper looks at the mean and repeatability of the values obtained by the Schirmer test in a normal Arab population Method: The test was performed on the right eyes of 23 young adult Saudi male subjects at five visits over two weeks. Result: Results showed that for each subject the test values were not repeatable, varying widely over the period of evaluation. The mean value was estimated at 10.6 mm and the 95 per cent confidence limits were 7.9 and 13.3 mm. It was also established that the greater the amount of tears, the greater the variability. Conclusion: This study supports the claim that the Schirmer test is not repeatable and hence is unreliable. Therefore, caution should be exercised in employing it for clinical diagnosis. (Clin Exp Optom 1995; 78: 5: 190–193)  相似文献   
17.
Peripheral blood mononuclear cells (PBMC) from Rhesus monkeys previously immunized with bovine type II collagen to induce arthritis were cultured with the same antigen. Because the native protein is poorly soluble in culture medium a heating step is often used. The antigen in this form induced PBMC proliferation, but epitopes for the induction of antibody production and arthritis were lost. To keep the native protein intact it was coated on affigel beads. With the immobilized antigen specific antibody production could be induced.  相似文献   
18.
Summary Estrogen has an important role in stimulating the growth of breast carcinomas. Inhibition of estrogen production is therefore a logical treatment strategy. A number of selective inhibitors have been developed against aromatase, a cytochrome P-450 enzyme which catalyzes the rate limiting step in the biosynthesis of estrogens. The mechanisms of the aromatase reaction, current knowledge of the enzyme, and regulation of its expression are discussed as the basis for inhibitor development. Two classes of aromatase inhibitors, steroidal and non-steroidal compounds, are now coming into use. Among the steroid substrate analogues, 4-hydroxyandrostenedione (4-OHA) has been shown to be effective in breast cancer patients with advanced disease and was recently approved for treatment in the United Kingdom. Several different classes of compounds which act as aromatase inhibitors are currently in clinical trials and should provide breast cancer patients with a number of treatment options. Among these are highly potent and selective non-steroidal inhibitors which have recently been found to suppress plasma and urinary estrogens over 95% in breast cancer patients. The potency of these newer aromatase inhibitors provides the opportunity to determine whether complete suppression of estrogen production and action will result in enhanced tumor regression.  相似文献   
19.
Semiconductor manufacturing: an introduction to processes and hazards   总被引:2,自引:0,他引:2  
Recent studies suggest that semiconductor workers have an increased incidence of work-related illness. Semiconductor manufacturing is a chemically intensive industry involving many potentially hazardous operations. As this industry moves into new geographic areas, health care professionals will be asked to evaluate medical or workplace conditions associated with unfamiliar and complex production processes. This paper provides an overview of semiconductor manufacturing processes for these health practitioners. Each step of device fabrication is detailed with its attendant chemical and physical hazards. Broader concepts of industrial control technology, clean room ventilation, and ergonomics are explained. The hazards are tabulated to allow rapid assessment of the risks inherent to each processing step. References have been chosen to guide the reader to more indepth information.  相似文献   
20.
AIMS: The rate of autologous urine production should not have a major disturbing influence on cystometric urodynamic parameters such as first filling sensation, normal desire to void, strong desire to void, and cystometric bladder capacity. Instructions to patients and drinking behavior can have considerable impact, especially if filling cystometry is preceded by free uroflowmetry. We studied the influence of autologous urine production during filling cystometry on total bladder volume. METHODS: Urodynamic investigations performed between September of 2000 and February of 2001 were analyzed. Only those urodynamic investigations for which total bladder capacity could be calculated were taken into account (i.e., catheterization before and after cystometry and no urine loss during the investigations). RESULTS: After screening, 186 investigations were used for further analysis. Mean filled volume (external infusion plus autologous urine production) was 346 +/- 152 mL, but mean real bladder capacity (i.e., voided volume + residual urine) was 391 +/- 170 mL. In all patients, 14% extra urine was produced due to autologous urine production (mean filling rate, 6.1 mL/min). In 42% of the investigations, the real bladder capacity was more than 110% of the infused volume. In 18% of the patients, the contribution of natural bladder filling was more than 25% of the infused volume. CONCLUSIONS: Natural bladder filling plays a substantial role during filling cystometry and has a disturbing influence on calculated urodynamic parameters. Attention should be paid to patient instructions before the urodynamic investigation. The combination of free uroflowmetry followed by filling cystometry should be avoided. This avoidance is especially important if interventional studies are performed. Careful interpretation of studies depending on bladder capacity parameters is mandatory, and such parameters should be corrected for autologous bladder filling.  相似文献   
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