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121.
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Subcellular fractions, isolated from the lymphoid cell line IM-1, are capable of stimulating a weak proliferative response in allogeneic lymphocytes. They also stimulate the generation of cytotoxic effector lymphocytes. The proliferative response to subcellular fractions, as measured by 3H-thymidine incorporation, is only one-fourth to one-sixth as great as that to intact IM-1 cells, suggesting that a component(s) synthesized during the mixed lymphocyte reaction (MLR), or a short-lived cellular constituent, may be responsible for the ability of intact cells to stimulate a lymphocyte proliferative response. This component appears to be lacking or in limiting quantity in subcellular fractions, including the soluble fractions. In contrast to the decreased proliferative response to subcellular fractions, the cytotoxic capacity of the stimulated lymphocytes is comparable to that after stimulation by intact IM-1 cells. The data demonstrate that, in this system, cytotoxic effector lymphocytes can be generated in the absence of the extensive proliferative response normally observed in the MLR. The antigenic stimulus responsible for the generation of cytotoxic effector cells appears to reside on intracellular components as well as on plasma membrane. In these reactions, specificity is shown by the failure of the cytotoxic cells to release 51Cr from autologous target cells. In fact, reactivity of lymphocytes stimulated by subcellular fractions is more specific than the reactivity of cells stimulated by intact IM-1 as judged by their lytic capacity for another target cell, RPMI 4265.  相似文献   
123.
Synopsis The histochemical localization of carbohydrates, ribonucleoproteins (RNA), lipids, some hydrolytic enzymes, succinate and lactate dehydrogenase and acetylcholinesterase were investigated in the prostate, urethral and bulbourethral glands of the camel. These glands probably secrete carbohydrate-protein complexes. In the bulbourethral glands, they are sulphated mucopolysaccharides. RNA was seen in the cytoplasm of the prostate and urethral glands. Neutral lipids were cytoplasmic and present in moderate amounts in the prostate and urethral glands and in traces, in the bulbourethral gland. Acid phosphatase-containing granules were abundant in the prostate, moderate in the urethral glands and in traces in the bulbourethral glands. Alkaline phosphatase was observed in the apical cytoplasm of the prostate and bulbourethral glands and in the ducts of the urethral glands. ATPase and adenosine 5-monophosphatase were seen in the basal laminae and interstitial tissue. In the urethral glands, adenosine 5-monophosphatase was distributed diffusely in the cytoplasm. Succinate dehydrogenase was seen in the urethral and bulbourethral glands. Varying degrees of lactate dehydrogenase activity was observed in all the glands. Acetylcholinesterase was confined to neural elements. The pars disseminata and the urethral glands were considered as two distinct glandular zones along the pelvic urethra. The significance of these histochemical results is discussed.  相似文献   
124.
Papiha  S. S.  Roberts  D. F.  Ali  S. G. M.  Islam  M. M. 《Human genetics》1975,29(4):285-290
Human Genetics - In a sample of Bengali Muslems from Dacca, haptoglobin, group-specific component, haemoglobin, adenosine deaminase, adenylate kinase, 6-phosphogluconate dehydrogenase,...  相似文献   
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Photoreceptor degeneration (PD) refers to a group of heterogeneous outer retinal dystrophies characterized by the death of photoreceptors. Both oxidative stress and inflammation are involved in the pathogenesis of PD. We investigate whether vitamin D has a potential for the treatment of PD by evaluating the anti‐oxidative stress and anti‐inflammatory properties of the active form of vitamin D3, 1,α, 25‐dihydroxyvitamin D3, in a mouse cone cell line, 661W. Mouse cone cells were treated with H2O2 or a mixture of H2O2 and vitamin D; cell viability was determined. The production of reactive oxygen species (ROS) in treated and untreated cells was measured. The expression of key anti‐oxidative stress and inflammatory genes in treated and untreated cells was determined. Treatment with vitamin D significantly increased cell viability and decreased ROS production in 661W cells under oxidative stress induced by H2O2. H2O2 treatment in 661W cells can significantly down‐regulate the expression of antioxidant genes and up‐regulate the expression of neurotoxic cytokines. Vitamin D treatment significantly reversed these effects and restored the expression of antioxidant genes. Vitamin D treatment also can block H2O2 induced oxidative damages. The data suggested that vitamin D may offer a therapeutic potential for patients with PD.  相似文献   
127.
There are few studies on rhinitis and sick building syndrome (SBS) among students in tropical countries. We studied associations between levels of five fungal DNA sequences, two mycotoxins (sterigmatocystin and verrucarol) and cat allergen (Fel d 1) levels in schools and rhinitis and other weekly SBS symptoms in the students. Fungal DNA was measured by quantitative PCR and cat allergen by ELISA. Pupils (N = 462) from eight randomly selected schools in Johor Bahru, Malaysia participated (96%). Dust samples were collected by cotton swabs and Petri dishes exposed for one week. None of the schools had a mechanical ventilation system, but all classrooms had openable windows that were kept open during lectures and indoor CO2 levels were low (mean 492 ppm; range 380–690 ppm). Weekly nasal symptoms (rhinitis) (18.8%), ocular (11.6%), throat (11.1%), dermal symptoms, headache (20.6%) and tiredness (22.1%) were common. Total fungal DNA in swab samples was associated with rhinitis (p = 0.02), ocular symptoms (p = 0.009) and tiredness (p = 0.001). There were positive associations between Aspergillus versicolor DNA in Petri dish samples, ocular symptoms (p = 0.02) and tiredness (p = 0.001). The level of the mycotoxin verrucarol (produced by Stachybotrys chartarum) in swab samples was positively associated with tiredness (p = 0.04). Streptomyces DNA in swab samples (p = 0.03) and Petri dish samples (p = 0.03) were negatively associated with tiredness. In conclusion, total fungal contamination, measured as total fungal DNA) in the classrooms, Aspergillus versicolor and verrucarol can be risk factors for rhinitis and SBS symptoms among students in the tropical country Malaysia.  相似文献   
128.
129.
Forty-four of 219 animals from Trinidad and Grenada, W.I., yielded 20 serotypes of Salmonella, 16 of which are known to have been associated with human infection in the United States in recent years. Toads (Bufo marinus) provided the greatest number of isolates. Other carriers were mammals, vultures, lizards, a tree-frog and a cave cockroach.  相似文献   
130.
Natural killer (NK) cells have significant capability in tumor immune-surveillance. The ability of lyse transformed cells immediately in an antigen-independent manner make them an attractive candidate for cancer cell therapy. Despite employment of NK cells in cancer immunotherapy, clinical trials are faced with serious limitations such as trouble with the penetration of NK cells in tumor sites, limited in vivo persistence, and tumor microenvironment interference. Taken together, the NK-cell cancer therapy is still infant scenario that has a long way to be translated in clinic. Current article first reviews characteristic features of NK lymphocytes. Then, it discusses about important disruptive barriers and motivator in the developmental stages of NK cells like as tumor microenvironment. Finally, some revolutionary approaches are highlighted utilizing of NK cells in cancer therapy.  相似文献   
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