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1.
2.
P M Battey J T Fulenwider R B Smith L G Martin M T Stewart G D Perdue 《Southern medical journal》1987,80(4):479-482
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation. 相似文献
3.
Medical experts have disputed whether childhood cyclic vomiting is a manifestation of epilepsy or a migraine equivalent. Quantitative EEG provides an objective measure of changes in brain activity during and between episodes. This paper reports reversible changes involving two episodes in a patient whose history included cyclic vomiting and emotional/behavioural problems. Abnormal delta activity seen during both episodes resolved at follow-up, when the patient asymptomatic. The brain wave changes counter the hypothesis that vomiting in these patients is psychosomatic, and support the interpretation of cyclic vomiting as a migraine equivalent. 相似文献
4.
Peter R. Martin Sondra Levin Giovanni Impeduglia Yoomi Choe John Karanian Anil B. Mukherjee 《Psychopharmacology》1989,97(2):253-256
To determine whether prenatal thiamine deficiency, a frequent concomitant of alcoholism, reduces the response to ethanol during adulthood in the rat as does ethanol exposure in utero (Abel et al. 1981), pregnant Sprague-Dawley rats received either control or thiamine deficient diets together with daily injections of the thiamine antagonist pyrithiamine. At 7 months of age, male offspring were exposed to precisely regulated ethanol vapor concentrations in an inhalation chamber for 24 h and blood ethanol concentrations (BECs) and ethanol-induced intoxication were determined. Prenatally thiamine deficient rats and controls were indistinguishable in terms of appearance, body and liver weights, and the ratios of liver to body weight and brain to liver weight. However, total body water was significantly greater, and BECs and behavioral impairment were decreased, in the experimental rats. These findings indicate that prenatal thiamine deprivation is associated with reduced pharmacologic effect of ethanol as a result of increases in its volume of distribution and rate of metabolism. 相似文献
5.
A 1975 report stated that a schizophrenic genotype may be manifested in infants by a neurointegrative defect called pandysmaturation. Recent evidence supports this: (1) 12 studies found delayed development in schizophrenics' infants and in preschizophrenics; (2) "blind" psychometric evaluations favored an adult schizotypal disorder in four to six of seven high-risk subjects with pandysmaturation in the New York study; and (3) finally, in a partial replication of this method using the Jerusalem data, blind diagnoses of "probable" and "possible" pandysmaturation were significantly related to a parental diagnosis of schizophrenia and to cognitive and motor neurointegrative deficits at 10 years. Obstetrical complications were unrelated to diagnosis, pandysmaturation, or outcome in the overall sample. However, we found a small subgroup of schizophrenic offspring in whom the most severe motor deficits at follow-up were related to obstetrical complications, pandysmaturation, and low birth weight. 相似文献
6.
Characterization of three species of nucleocapsids of equine herpesvirus type-1 (EHV-1). 总被引:26,自引:0,他引:26
Three distinct species of nucleocapsids of equine herpesvirus type-1 (EHV-1) were isolated from infected L-M cell nuclei. The particles were classified on the basis of their densities in Renografin gradients as Light (L; ? = 1.237 g/cc), Intermediate (I; ? = 1.244 g/cc), and Heavy (H; ? = 1.258 g/cc). Analysis of the three nucleocapsid species, radioactively labeled with an 3H-labeled or 14C-labeled amino acid mixture, by discontinuous SDS-polyacrylamide-gel electrophoresis revealed significant and reproducible differences in their structural protein compositions. H nucleocapsids were comprised of six major proteins (I, II, III, IV, IVa, and V) with respective molecular weights of 148,000, 59,000, 46,000, 37,000, 30,000, and 18,000; these proteins comprised 63.7, 9.3, 6.0, 10.8, 5.3, and 4.1%, respectively, of total protein. These six proteins were also present in I nucleocapsids, however nucleocapsid protein IVa (MW, 30,000) was present only as a minor component and comprised less than 1% of total protein. L nucleocapsids were comprised of only four of these major structural proteins, as proteins III (MW, 46,000) and IVa (MW, 30,000) were absent. In addition, several minor proteins, each comprising less than 1% of total nucleocapsid protein, were present in each nucleocapsid species.Electrophoretic analysis of nucleocapsids labeled with [3H]arginine indicated that proteins extremely rich in arginine are not present in these three species. Phosphoproteins both of enveloped virions and of nucleocapsids were identified by electrophoretic analysis of particles radioactively labeled with inorganic phosphate (H332PO4). Twelve virion structural proteins were phosphorylated in vivo; five of these, including the major virion phosphoprotein VP 10 (MW, 127,000), were envelope specific proteins. Four of these 12 viral proteins were also phosphorylated in nucleocapsids, however the pattern of phosphorylation of nucleocapsid proteins varied among the three species. The two major phosphoproteins of nucleocapsids were proteins III and IVa which are absent in L nucleocapsids; protein V is phosphorylated only in H nucleocapsids.Analysis of the DNA content of the three nucleocapsid species indicated that preparations of H nucleocapsids contain more DNA than do those of the I and L species. Electron microscopic analysis of the nucleocapsids supported these results, as L and I nucleocapsids lack a dense inner nucleoid structure characteristic of the H species. 相似文献
7.
William J. Engellenner Lloyd Rozboril Valerie P. Perdue Richard G. Burright Peter J. Donovick 《Physiology & behavior》1982,28(1):177-179
An inexpensive and easily constructed metabolic cage for mice is presented. This apparatus can reliably monitor food and fluid consumption, as well as urine and fecal output, in a relatively non-intrusive manner. 相似文献
8.
Monocyte/macrophage activation by normal bacteria and bacterial products: implications for altered epithelial function in Crohn's disease 总被引:2,自引:0,他引:2
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Zareie M Singh PK Irvine EJ Sherman PM McKay DM Perdue MH 《The American journal of pathology》2001,158(3):1101-1109
Intestinal immune cells are less reactive than those in the peripheral blood; however, such cells from patients with Crohn's disease may be more responsive to bacterial products. Our study examined if nonpathogenic bacteria or lipopolysaccharide (LPS), can affect epithelial function in the presence of monocytes/macrophages. Lamina propria mononuclear cells (LPMCs) and peripheral blood monocytes (PBMs) were obtained from patients with Crohn's disease and control patients. Filter-grown T84 epithelial monolayers were co-cultured with nonactivated or LPS-activated LPMCs or PBMs for 48 hours. Epithelial secretory [baseline short-circuit current (Isc) and DeltaIsc to forskolin] and barrier (transepithelial electrical resistance) parameters were measured in Ussing chambers. LPS-activated PBMs from both controls and patients with Crohn's disease significantly increased Isc ( approximately 300%) and reduced transepithelial electrical resistance ( approximately 40%). Epithelial function was not altered after co-culture with control LPMCs +/- LPS. However, LPMCs from patients with Crohn's disease spontaneously secreted tumor necrosis factor-alpha, and induced epithelial changes similar to those produced by LPS-activated PBMs. Co-culture with control Escherichia coli and PBMs induced comparable changes in epithelial physiology, which were abrogated by anti-tumor necrosis factor-alpha antibody. We conclude that LPMCs of patients with Crohn's disease are spontaneously activated, possibly by gram-negative luminal bacteria, and can directly cause significant alterations in epithelial ion transport and barrier functions. 相似文献
9.
This study compared the tissue distribution and cellular expression of Ia antigen in jejunal and ileal epithelium at various stages of intestinal inflammation produced by infecting rats with the nematode parasite Nippostrongylus brasiliensis. Tissues were examined at Day 0 (control), Day 4 (early), Day 10 (acute), and Day 16 (recovering). Frozen sections were stained with the MRC OX-4 anti-Ia monoclonal antibody using an immunoperoxidase technique. Control jejunal sections demonstrated positive epithelial Ia expression mainly in the mid-regions of the villi. The stain appeared to be mostly intracellular in the supranuclear area; the basolateral membrane stained faintly. At Day 4, a greater percentage of the epithelial cells expressed Ia, including those at the tips of the villi. The Day 10 sections demonstrated no staining at all of villus enterocytes, but the crypt epithelium was Ia positive. At Day 16, the pattern of Ia expression was similar to that seen in the early infection. In the ileum, stain was present in enterocytes over most of the villus and crypt regions except in the villus-crypt junction and did not change significantly during infection. We conclude that the changes in the expression of Ia antigen by intestinal epithelium are local to the site of infection and probably occur as a consequence of the host's inflammatory response. 相似文献
10.
Sondra Schlesinger Barbara Weiss Daniel Goran Milton Schlesinger Ranieri Cancedda 《Medical microbiology and immunology》1974,160(4):311-329
Our studies on the formation of Sindbis virus proteins have established that: 1. one of the two envelope proteins (E2) accumulates in infected cells as a higher molecular weight precursor that is slowly converted to the virion protein; 2. the large protein (mol. wt 130000 daltons), that accumulates in cells infected with a temperature-sensitive mutant of Sindbis virus contains sequences of the three virion proteins; and 3. the protein (mol. wt. 100000 daltons) isolated from BHK cells infected with Sindbis virus is related in sequence to the two envelope proteins.We have investigated the formation of defective-interfering (DI) particles of Sindbis virus and their ability to inhibit the replication of standard virus. BHK cells infected with passages of Sindbis virus containing DI particles accumulate a species of RNA (20S) that is about half the molecular weight of the 26S RNA. We have demonstrated by competitive hybridization experiments that 20S RNA contains half the sequences of 26S RNA. We also present evidence that in contrast to 26S RNA, 20S does not bind to polysomesin vivo and is not translatedin vitro.Presented on the Meeting on Studies on Virus Replication of the Commission of the European Communities in Brüssel, May 1974. 相似文献