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51.
N E Miller C H Bolton T M Hayes D Bainton J W Yarnell I A Baker P M Sweetnam 《Journal of epidemiology and community health》1988,42(3):220-225
In surveys of 4860 middle-aged men in Caerphilly (South Wales) and Speedwell (Bristol) alcohol consumption has been related to high density lipoprotein (HDL) cholesterol and its major subfractions, HDL2 and HDL3, measured in a single fasting blood sample. The results confirm that high density lipoprotein cholesterol concentration increases as the amount of alcohol regularly consumed increases. The relationship appears to be linear and is independent of age, smoking habit, body mass index, low density lipoprotein cholesterol and plasma total triglyceride. This rise in HDL cholesterol is not mediated through either HDL2 cholesterol or HDL3 cholesterol alone. Both subclasses increase significantly and by similar amounts with increasing alcohol intake. 相似文献
52.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
53.
The Effects of Serum from Patients with Acute Liver Failure on the Growth and Metabolism of Hep G2 Cells 总被引:6,自引:0,他引:6
In many bioartificial liver systems currently being designed and evaluated for use in fulminant hepatic failure, direct contact is required between the patient's blood and the liver cells in the device. The efficacy of such devices will be influenced by the interaction of fulminant hepatic failure (FHF) patient serum with the cells. We have found that FHF serum inhibits the growth rate and the synthesis of DNA, RNA, and protein; disturbs glutathione homeostasis; and induces morphological changes in cultured human Hep G2 cells. These interactions should influence the design of bioartificial liver devices based on proliferating cell lines and indicate the requirement to pretreat FHF patient plasma to reduce the toxin load. 相似文献
54.
55.
Normal and regenerating optic fibers in goldfish tectum: HRP-EM evidence for rapid synaptogenesis and optic fiber-fiber affinity 总被引:1,自引:0,他引:1
The distribution of normal and regenerating retinal fibers and synapses was studied on tectum in goldfish by light (LM) and electron microscopy (EM). Since labeling of the early regenerating fibers was previously reported to be difficult, a new 'cold-fill' HRP labeling protocol was developed, which labeled regenerating optic fibers and terminals on tectum as early as 14 days after nerve crush when they first arrive on tectum. In order to characterize the laminar distribution of optic afferents in normal fish and in fish regenerating for 14-240 days, EM photomontages of areas 14 microns wide by 160 microns deep through the HRP-labeled primary optic innervation layer (S-SO-SFGS) were constructed. The time points in regeneration that were examined spanned the period in which others have shown that an initially diffuse retinotopic map becomes spatially restricted. At the LM level regenerating optic fibers were restricted to the optic lamina. They reinnervated tectum in an anterior to posterior sequence as previously seen with autoradiography. In addition, at 14 days, some "pioneer" optic fascicles were found to have already grown to posterior tectum where they gave rise to branches with boutonlike terminations and growth-cone-like processes. Form the ultrastructural analysis it was clear that optic fibers and terminals observed strict laminar boundaries as they partitioned themselves in the optic laminae (S, SO and SFGS) in both normal and regenerating fish. The behavior of optic fibers was lamina specific with respect to synapse formation and the orientation of fiber outgrowth. As early as 14 days regeneration, optic fibers made synapses onto the four types of postsynaptic profiles observed in normal fish. Numerous optic terminals were labeled at 14 days, and there appeared to be no waiting period between fiber ingrowth to the SO and synapse formation in the S and SFGS. At 14-60 days, atypical synaptic contacts which appear to be nascent synapses were made by labeled optic fibers in fascicles and by growth-cone-like processes. By 21-30 days, the density of optic terminals was high and there were many more fasciculated optic fibers in the SFGS than normal as late as 350 days. These findings suggest that optic fiber lamination is highly constrained by tectal cues, that fibers rapidly regenerate many synaptic terminals before retinotopic map refinement is complete, and that fibers have a strong affinity for each other. 相似文献
56.
Youths of today are forced to deal with the external pressures of alcohol and drug abuse on all levels-from the older youngsters across the street pressuring them to be "cool," to the "cute dog" enticing them with the glamour of being the original "party animal." Through today's mass communications, young people are exposed to negative, self-destructive attitudes. It is important, therefore, to expose them to a more positive influence and try to reach them through parental guidance, personal contact, and peer pressure. To achieve this, the University of Missouri's Kansas City Chapter of the American Pharmaceutical Association's Academy of Students of Pharmacy, in conjunction with the Metropolitan Kansas City Area Task Force on Alcohol and Other Drug Abuse, proposed the development of an annual drug abuse prevention program that specifically targets fifth graders in the greater Kansas City metropolitan area. A primary goal of Project Outreach (Organizations Unified to Reach Youth) is to unite drug abuse prevention programs in the greater Kansas City metropolitan area in their outreach efforts to give positive support to Kansas City's youth against alcohol and other drugs. Phase I of Project Outreach consisted of a series of programs for the parents in the community. Phase II entailed college students who spoke to fifth graders in their classrooms. These students also participated in poster and poem contents centered around drug abuse prevention. In Phase III, which featured an outstanding, motivated speaker, the sample group of 600 fifth graders in the area participated in a major event to give positive peer pressure to say no to drugs.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
57.
Charles B. Pratt Edwin C. Douglass William H. Meyer F. Ann Hayes Marc E. Horowitz Elizabeth I. Thompson Loraine Avery 《Investigational new drugs》1989,7(2-3):209-211
Summary 4 -Deoxydoxorubicin was given to 15 patients with drug-resistant pediatric malignant solid tumors with the objectives of determining the maximum tolerated dosage and dose-limiting toxicity. Maximum tolerated dosage was 36 mg/m2 given IV once every 3 weeks. Dose limiting toxicity was myelosuppression, which was severe and prolonged. Therapeutic benefits were not observed for these patients. 相似文献
58.
Assays of serum benzylamine oxidase (BzAO) have led some workers to postulate a relationship between elevated BzAO activity and diseases characterized by proliferating connective tissue. The present study was designed to determine whether BzAO activity of a cellular tissue is also affected. BzAO was assayed in homogenates of normal and atherosclerotic human aortae. Characterization done in normal aortae showed that BzAO is not a classical monoamine, diamine, polyamine, or lysyl oxidase, nor is it a ceruloplasmin. The enzyme is heat stable at 60 degrees C and is associated primarily with the microsomal fraction on density centrifugation. Compared with phenylethylamines and indoleamines, benzylamine is the best substrate. BzAO is sensitive to inhibition by hydrazines and chymotrypsin but not trypsin, and is insensitive to Triton X-100 and sulfhydryl-group blockade. BzAO activity of atherosclerotic plaque (expressed per gram wet weight or per milligram protein) was decreased markedly compared to that in adjacent, nonplaque regions and in normal aortae. However, on a per milligram DNA basis, the BzAO activity of plaque did not differ from that of nonplaque tissue. We conclude that there is a decreased cell population density in plaque, a contention supported by kinetic analysis. Plaque BzAO showed a decreased Vmax with no change in the Km of benzylamine compared with nonplaque tissue. Thus, if a relationship exists between BzAO activity and proliferating connective tissue, it is not apparent at the level of the cellular enzyme in atherosclerotic aortae of man. 相似文献
59.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
60.
Hayes S Turecki G Brisebois K Lopes-Cendes I Gaspar C Riess O Ranum LP Pulst SM Rouleau GA 《Human molecular genetics》2000,9(12):1753-1758
Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant disorder caused by the expansion of a polymorphic (CAG)(n) tract, which is translated into an expanded polyglutamine tract in the ataxin-2 protein. Although repeat length and age at disease onset are inversely related, approximately 50% of the age at onset variance in SCA2 remains unexplained. Other familial factors have been proposed to account for at least part of this remaining variance in the polyglutamine dis-orders. The ability of polyglutamine tracts to interact with each other, as well as the presence of intra-nuclear inclusions in other polyglutamine disorders, led us to hypothesize that other CAG-containing proteins may interact with expanded ataxin-2 and affect the rate of protein accumulation, and thus influence age at onset. To test this hypothesis, we used step-wise multiple linear regression to examine 10 CAG-containing genes for possible influences on SCA2 age at onset. One locus, RAI1, contributed an additional 4.1% of the variance in SCA2 age at onset after accounting for the effect of the SCA2 expanded repeat. This locus was further studied in SCA3/Machado-Joseph disease (MJD), but did not have an effect on SCA3/MJD age at onset. This result implicates RAI1 as a possible contributor to SCA2 neurodegeneration and raises the possibility that other CAG-containing proteins may play a role in the pathogenesis of other polyglutamine disorders. 相似文献