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991.
992.
Three previously healthy children developed gastroenteritis which led within a few days to systemic infections, two cases of bacteremia and one of meningitis. A lactose-fermentingSalmonella virchow strain was isolated from cerebrospinal fluid and blood cultures. In one case, this strain was also isolated from stool cultures. All the children had been fed the same milk formula. There was no other relationship between them. The batch of dried-milk formula was confirmed as the source of the infection by isolation of an identical lactose-fermentingSalmonella virchow strain by the Centro Nacional de Alimentación.  相似文献   
993.
In this study, a novel composite bone substitute was implanted in animal models (rats) and their in vivo characteristics were examined. A D,L-lactide and E-caprolactone copolymer (Mw: 80,000; Mn:40,000, and PI:2.00) was synthesized by ring-opening polymerization of the respective dimers using stannous octoate as the catalyst. The final ratio of D,L-lactide to epsilon-caprolactone obtained by 1NMR was 60/40. Hydroxyapatite (HA) powder was loaded in the copolymer. The HA/copolymer ratio was 60/40 (w/w). These composites were easily shaped by hand. Animal tests were performed on mature wistar rats (n=30). Defects were created on the proximal, the thickest part of the femur. The bone defects of the first group were filled with polymer/HA composite, the second group filled with only HA and the third group was left empty. Histologic examination of bone tissues showed new bone formation around the yellow-green polymer/HA composite material in the first group of animals whereas no evidence of new bone growth was observed in other groups.  相似文献   
994.
In order to evaluate the heart and liver responses after adriamycin (ADR) toxic aggression, with and without exogenous L-carnitine (CAR) protection, female Sprague-Dawley rats, body weight 40-60 g, were randomized into four groups: CON, ADR, CAR and CAR-ADR. ADR was injected i.v. at a dose of 15-18 mg/kg body wt (0.1 ml). CAR was administered i.v. at a dose of 20 mg (0.1 ml) before each subdose of ADR, and then orally at 180 mg/kg body wt daily for 12 weeks. Long-term cardiac and hepatic subcellular damage were determined by transmission electron microscopic analysis of ultrathin sections. The ADR-induced long-term cardiac subcellular pathology included loss, disruption and disassembly of myofibrils, and mitochondrial swelling and condensation. On the other hand, the ADR-induced subcellular hepatic alterations consisted of polymorphic mitochondria, cytoplasmic vacuolization and accumulation of lipid droplets. Apparently, cardiac tissue was more affected by ADR toxic aggression than hepatic tissue. However, these alterations were of less severity in protected groups, in both heart and liver, suggesting CAR as a possible hepatoprotector agent against ADR toxicity. Because of the liver-L-carnitine-heart relationship, studying ADR-hepatotoxicity could be helpful in the further understanding of severe ADR-cardiotoxicity.  相似文献   
995.
Immunofluorescence studies on Epstein-Barr virus (EBV)-transformed lymphoblastoid cells have previously shown that the latent membrane transforming protein (LMP-1) is found in patch-like inclusions which also immunostain for vimentin. We now show that EBV transformation causes a major reorganization of intermediate filaments, microtubules, mitochondria, and lysosomal elements, which generally become oriented around the microtubule organizing centre. Immunogold electron microscopy shows that LMP-1 is primarily concentrated in secondary lysosomes together with ubiquitin-protein conjugates and heat-shock protein 70. Intermediate filament inclusion formation with the above characteristics may be a general response triggered by other membrane glycoproteins; as seen, for example, in major human neurodegenerative diseases such as diffuse Lewy body disease.  相似文献   
996.
This article reports on the experience with 38 biopsies from nasal mucosa, submitted with the question of immotile cilia syndrome. Fixation in glutaraldehyde with MgSO4 is preferable. At least 50 cilia should be scrutinized in the electron microscope, and dynein arms, radial spokes, sheaths, nexin links and orientation should be tabulated. Six cases displayed virtual absence of inner and outer dynein arms. The orientation of these cilia was random. Two of the patients had situs inversus. In biopsies considered not to represent the immotile cilia syndrome, about four inner and seven outer dynein arms were found per cilium.  相似文献   
997.
Two cases of acute Wernicke's encephalopathy with severe hypothermia as the major presenting feature are reported. Treatment with thiamine was rapidly introduced, but hypothermia nevertheless persisted for several weeks, at times masked by intercurrent infections.  相似文献   
998.
Constitutional t(15;17)   总被引:2,自引:0,他引:2  
  相似文献   
999.
The fine specificity of nine cytolytic T lymphocyte (CTL) clones obtained after stimulation of HLA-B27- responder lymphocytes with B27.1+ lymphoblastoid cell lines has been analyzed. These clones defined three different reaction patterns when tested against a panel of target cells including those expressing all known HLA-B27 subtypes: (a) specific recognition of HLA-B27.1, B27.2 and B27d, (b) selective reactivity with B27.1, B27d and HLA-B40 and (c) selective recognition of B27.1, B27.2, B27d, B27f and B40. Representative clones within each group were analyzed in detail. Differences in lytic ability of the various susceptible targets within each group were established by cold target inhibition analyses and by blocking experiments with anti-CD3 and anti-CD8 monoclonal antibodies. When correlated with the known structure of the HLA-B27 subtypes, these results demonstrate the critical relevance of amino acid changes within residues 77-81 and at position 152 in modulating allospecific CTL recognition of HLA-B27.1 and suggest that these residues could be involved in the structure of immunodominant regions of this antigen. The observed cross-reactions with HLA-B40, differing from B27.1 in 16 amino acid residues, suggest that the simultaneous occurrence of multiple amino acid changes could have mutually compensatory effects, so that a cross-reactive epitope might result from various combinations of polymorphic residues.  相似文献   
1000.
Autonomic and peripheral nerve functions as well as the possible short-term effect of a novel aldose reductase inhibitor (ARI) on neuropathy were evaluated in 30 male type I diabetics (age 25-44 years, mean 34; duration of diabetes 10-20 years, mean 34) with neurographic signs of peripheral neuropathy (PN). Autonomic neuropathy (AN) was established by the heart rate reactions to deep breathing (E/I ratio = vagal function) and to tilt (acceleration index = sympathetic and vagal functions; the brake index = vagal function). Twenty-nine patients, 13 with AN, completed the study. Among neurographic variables, only sural nerve function tests correlated with autonomic functions. Patients with AN showed significantly lower mean sensory action potential amplitudes (SAPA) sural, indicating axonal losses, than patients without AN (3.58 +/- 0.79 microV v. 7.34 +/- 1.12 microV; p less than 0.01). PN as measured by neurography did not improve during ARI treatment. On the other hand, vagal function (brake indices) improved (p less than 0.05) during ARI in AN patients.  相似文献   
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