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101.
102.
The effect of lipid lowering diet on low density lipoprotein (LDL) receptor activity has been studied in freshly isolated peripheral blood mononuclear cells (PBMCs) from 16 hypercholesterolemic male subjects during a three weeks' dietary intervention trial. The participants were randomized to an intervention group or to a control group. The subjects in the intervention group had a non-significantly larger increase in LDL receptor activity, determined as degradation of 125I-LDL at 37 degrees C, than the control group (49.7 +/- 18.1 and 35.4 +/- 21.2 ng/mg, respectively). Irrespective of assignment to the intervention group or control group, the eight subjects with the largest reduction in total serum cholesterol had significantly larger absolute and percentage increases in LDL receptor activity than the eight subjects with the smallest reduction in total serum cholesterol (p less than 0.05). Thus, it appears that the cholesterol reduction that can be achieved in humans by dietary intervention results in a small increase in LDL receptor activity in freshly isolated PBMCs.  相似文献   
103.
Psychological functioning across stages of treatment for infertility   总被引:12,自引:0,他引:12  
Psychological functioning was examined for a cross section of 104 couples in different stages of medical investigation for infertility. Couples were separated into three stages based upon the length of time they had been pursuing medical treatment for infertility: year 1, year 2, and year 3 and beyond. Emotional strain was moderately elevated during the first year, returned to more normal levels during the second year, and showed marked increases beyond year 3. Indices of marital adjustment and sexual satisfaction were stable across the first two stages but deteriorated after the third year. These data suggest that the stage of treatment may exert a major influence upon psychological functioning for infertile couples pursuing medical assistance. The results are consistent with a model of psychological strain that reflects an acute stress reaction to the initial diagnosis and treatment overlaid with a chronic strain response to longer-term treatment.Research was aided by a grant-in-aid of research from Sigma Xi, The Scientific Research Society, a research fellowship from the University of South Carolina, and NIMH Institutional Training Grant MH-15930.  相似文献   
104.
Unmethylated CpG motifs found in bacterial DNA are potent activators of the innate and acquired immune systems, and rapidly induce the production of proinflammatory cytokines. We hypothesized that CpG DNA may also elicit the production of prostaglandins (PG), which are central lipid mediators of the immune and inflammatory response. To test our hypothesis, we stimulated murine spleen cells and RAW 264.7 murine macrophage cells with CpG DNA and assessed the effects on the PG synthesis pathway. Compared to control, DNA-containing CpG motifs induced >5-fold increase in PGE (2) production and rapidly up-regulated cyclooxygenase-2 (COX-2) at both the mRNA and protein level. CpG DNA was an extremely strong inducer of COX-2 as concentrations as low as 3 ng/ml induced COX-2 protein expression. The CpG DNA-induced PGE (2) down-regulated the immune response elicited by CpG. Blockade of PGE (2) production with selective COX-2 inhibitors or neutralizing anti-PGE (2) antibody markedly enhanced IFN-gamma secretion in vitro from CpG DNA-stimulated spleen cells. Moreover, selective COX-2 inhibition increased CpG DNA-induced IFN-gamma secretion in vivo. Inhibition of COX-2 also increased CpG DNA-induced lytic activity of NK cells. Taken together, these data indicate that DNA containing CpG motifs is a potent inducer of COX-2 and PGE (2) production. CpG-induced PG may subsequently down-regulate the immune and inflammatory responses elicited by the CpG DNA.  相似文献   
105.
Eight mutations in the gene (the RYR1 gene) encoding the calcium release channel of sarcoplasmic reticulum (SR) in skeletal muscle are so far known to be very closely linked to malignant hyperthermia susceptibility in man and are regarded to be causative. We have examined 41 Swedish families where malignant hyperthermia had occurred in at least one member during anaesthesia, with respect to three of the known mutations. The mutations were Arg163Cys; Ile403Met and Arg614Cys (also known as the "pig mutation"). In three (i.e. 7%) of the families we detected the Arg614Cys mutation, and this was the only one of the mutations searched for that was observed. This indicates that other mutations than those searched for in this study must cause malignant hyperthermia susceptibility in most Swedish malignant hyperthermia susceptible families.  相似文献   
106.

Background  

The CC chemokine receptors CCR1, CCR2 and CCR5 are critical for the recruitment of mononuclear phagocytes to the central nervous system (CNS) in multiple sclerosis (MS) and other neuroinflammatory diseases. Mononuclear phagocytes are effector cells capable of phagocytosing myelin and damaging axons. In this study, we characterize the regional, temporal and cellular expression of CCR1, CCR2 and CCR5 mRNA in the spinal cord of rats with myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (MOG-EAE). While resembling human MS, this animal model allows unique access to CNS-tissue from various time-points of relapsing neuroinflammation and from various lesional stages: early active, late active, and inactive completely demyelinated lesions.  相似文献   
107.
We present the result of a cytogenetic study of a case of follicular carcinoma of the thyroid and its metastasis. Both tumors have a low number of chromosomes. The primary tumor is characterized by a idic(22;22)(p11;p11). The skeletal metastasis has also structural abnormalities of chromosome 22.  相似文献   
108.
Bengt  Berg 《Tissue antigens》1981,18(5):306-315
The influence of HLA-A, B-matching on the results of 362 cadaver renal transplantations was analyzed. Of these, 34 of the patients had diabetes and 105 were 55 years old or more. The case material was divided into groups, based on the number of HLA-A, B incompatibilities. The occurence of factors having a possible bearing on kidney graft survival was determined in each match group. It was found that several of these factors, such as the immunosuppressive agents given and the number of high-risk patients, were unequally distributed in the various groups. This may be related to changes in policy that have occured since the transplant unit was moved to Huddinge Hospital in November 1973. In order to obtain homogeneous case material, the Huddinge series was analyzed separately.
A significant difference in survival was found in both materials between transplants with 2 or less incompatibilities and those with more than 2 incompatibilities. A significant difference in patient survival between these two groups was found in the total case material.  相似文献   
109.
110.
Escherichia coli C25 maintained population levels of 10(9) to 10(10) per g of cecum and translocated to 100% of the middle mesenteric lymph nodes in gnotobiotic mice monoassociated with E. coli C25. Intragastric inoculation of these mice with the cecal contents from specific-pathogen-free mice reduced the population levels of E. coli C25 to 10(6) per g of cecum and completely inhibited translocation to the mesenteric lymph nodes. Intragastric inoculation with heat-treated, Formalintreated, or filtered cecal contents did not reduce the population levels of E. coli C25 or reduce the incidence of translocation of E. coli C25 to the mesenteric lymph nodes. Thus, viable bacteria apparently are required in the cecal contents inocula to reduce the population levels and the incidence of translocation of E. coli C25. Treatment with streptomycin plus bacitracin decreased the anaerobic bacterial levels in these gnotobiotic mice, allowing increased population levels of E. coli C25 and increased translocation to the mesenteric lymph nodes. E. coli C25 also translocated to the mesenteric lymph nodes of specific-pathogen-free mice treated with streptomycin and bacitracin before colonization with E. coli C25. The high cecal population levels of E. coli C25 in these antibiotic-decontaminated specific-pathogen-free mice apparently overwhelm any barrier to translocation exerted by the immunologically developed lamina propria of the specific-pathogen-free mice. Inoculation of gnotobiotic mice with a cecal flora also reduced the population levels of an indigenous strain of E. coli with a concomitant inhibition of translocation of the indigenous E. coli to the mesenteric lymph nodes. Thus, bacterial antagonism of the gastrointestinal population levels of certain indigenous bacteria, such as E. coli, by other members of the normal bacterial flora appears to be an important defense mechanism confining bacteria to the gastrointestinal tract.  相似文献   
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