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91.
92.
Type 1 diabetes is the consequence of exposure of genetically susceptible individuals to specific environmental precipitants. The innate immune system provides the initial response to exogenous antigen and links with the adaptive immune system. The aim of this study was to assess the role of polymorphisms occurring in the cytoplasmic region of toll-like receptor (TLR) 3 gene and immediate 5' sequence, in subjects of Zulu descent with type 1 diabetes in KwaZulu-Natal, South Africa. Seventy-nine subjects with type 1 diabetes and 74 healthy normal glucose tolerant gender-matched control subjects were studied. Parts of exon 4 and exon 3/intron 3 of the TLR3 gene were studied by polymerase chain reaction, direct sequencing and restriction enzyme digestion with Bts 1. Of the nine polymorphisms studied, a significant association with type 1 diabetes was found for the major allele in the 2593 C/T polymorphism and for the minor alleles in the 2642 C/A and 2690 A/G polymorphisms, which were found to be in complete linkage disequilibrium. Correction of the P-values for the number of alleles studied, however, rendered the results no longer significant. These results suggest that polymorphisms in the TLR3 gene, which is part of the innate immune system, may be associated with type 1 diabetes in this population.  相似文献   
93.
High level of plasma creatinine occurs in renal insufficiency, uremia, and other diseases. At present lowering of this metabolite is done by using dialysis and other techniques. In this article, we report the use of artificial cells microencapsulated genetically engineered E. coli DH5 cells for lowering plasma creatinine in-vitro and in-vivo. Result shows that artificial cells were able to lower plasma creatinine in-vitro from 21.80 +/- 1.10 mg/dl to 21.80 +/- 1.10 mg/dl in 60 minutes and to 19.34 +/- 0.60 mg/dl in 3 hours. Result also shows that when given orally on a daily basis, artificial cells microencapsulated genetically engineered E. coli DH5 cells were also able to lower plasma creatinine in rats.  相似文献   
94.
Biological membranes decorated with suitable contrast agents give rise to nonlinear optical signals such as two-photon fluorescence and harmonic up-conversion when illuminated with ultra-short, high-intensity pulses of infrared laser light. Microscopic images based on these nonlinear contrasts were acquired at video or higher frame rates by scanning a focused illuminating spot rapidly across neural tissues. The scan engine relied on an acousto-optic deflector (AOD) to produce a fast horizontal raster and on corrective prisms to offset the AOD-induced dispersion of the ultra-short excitation light pulses in space and time. Two membrane-bound derivatives of the green fluorescent protein (GFP) were tested as nonlinear contrast agents. Synapto-pHluorin, a pH-sensitive GFP variant fused to a synaptic vesicle membrane protein, provided a time-resolved fluorescent read-out of neurotransmitter release at genetically specified synaptic terminals in the intact brain. Arrays of dually lipidated GFP molecules at the plasma membrane generated intense two-photon fluorescence but no detectable second-harmonic power. Comparison with second-harmonic generation by membranes stained with a synthetic styryl dye suggested that the genetically encoded chromophore arrangement lacked the orientational anisotropy and/or dipole density required for efficient coherent scattering of the incident optical field.  相似文献   
95.
"Spontaneous" remission of leukemia has been observed in both humans and animals. Bierman et al2 in 1953 reported 11 cases of remis- sion in acute lymphoblastic leukemia (ALL) of childhood following acute infectious disease. In 1979 we saw a case of ALL remission in a child following a severe attack of respiratory infection.  相似文献   
96.
97.
This paper highlights a series of studies using the male rhesus monkey that has led to a model for the control of the onset of puberty in higher primates. The model proposes that the timing of puberty in these species is governed by the duration of a central brake that, during juvenile development, holds in check the hypothalamic network of gonadotropin-releasing hormone (GnRH) neurons, which, in the adult, drive the pituitary-gonadal axis. The neurobiology of this hypothalamic brake, and the physiological mechanisms that time its application and removal, are incompletely understood. Nevertheless, the pubertal resurgence of pulsatile GnRH release, which terminates the juvenile phase of primate development and triggers the initiation of puberty in man and monkeys, is associated with structural and molecular remodeling of the hypothalamus. A major component of this developmental plasticity appears to involve neuropeptide Y (NPY). NPY inhibits GnRH release, and NPY gene expression in the hypothalamus is elevated during juvenile development when GnRH release is restrained. Since the changes in hypothalamic function and morphology that trigger primate puberty unfold in the absence of gonadal steroid feedback, the possibility is raised that, in addition to activating the pituitary-gonadal axis at this stage of development, they may also contribute directly to the causation of behaviors and affective states that emerge at adolescence.  相似文献   
98.
A combination of pharmacological and cold cardioplegia in with hypothermia without perfusion in open-heart surgery guarantee the reversible character of shifts in energy and free radical balance in the myocardium. However, this procedure can impair coronary micricirculation due to structural and functional changes in microvessel endothelium. Our results demonstrate that new cytoprotective approaches are extremely needed for cardiac protection during surgery.  相似文献   
99.
The authors surveyed a community-based population of 628 persons who were 65 and over and who lived either in a rural Maryland county or in Baltimore. For each subject, the number of different medical problems, the subject's capacity to perform physical tasks, and the ability to function were assessed. The number and type of medical problems tended to be the best predictors of whether or not hospital or physician's office care were used, and of the volume of physician's office visits for subjects who sought outpatient care. The subject's ability to function was the best predictor of whether or not the subject used a paid home aide and the volume of family caregiving. Implications for research on association between need and use of long-term care are discussed.  相似文献   
100.
Abstract This project studies the use of church volunteers to reduce cardiovascular disease risk factors among their fellow church members. Our findings focus on the first 12 months of the project and address the following questions: 1) Can volunteers implement these programs with no on-site professional staff? 2) Are volunteer efforts facilitated by a local volunteer task force? and 3) Are implementation efforts aided by readily available professional staff involvement? In the intervention churches, 220 certified Risk Factor Leaders conducted 82 group programs with 740 registrants and 104 blood pressure screenings with 1,834 contacts. Our study shows volunteers to be effective implementers of heart health programs in churches. The involvement of a task force seemed to facilitate volunteer recruitment. Churches with a lower level of professional involvement had more blood pressure screenings. The effect of a task force or professional assistance on other volunteer efforts did not reach statistical significance.  相似文献   
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