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1.
We report a case of recurrent calculi in a Kock pouch continent urinary diversion. An open operation was avoided by successfully excising the Marlex mesh and removing it with the associated calculi in an endoscopic fashion.  相似文献   
2.
Treatment of experimental pyelonephritis in the monkey   总被引:4,自引:0,他引:4  
Previous studies show that chronic pyelonephritis and end stage renal disease may follow acute pyelonephritis in children and adolescents when improperly or inadequately treated. Our study shows that there is a significant decrease in renal function following untreated acute bacterial pyelonephritis due to nephron loss. The acute inflammatory response is responsible for much of the renal damage, although damage from renal ischemia is an additional significant factor. The present study used a combination of an antibiotic and a xanthine oxidase inhibitor (allopurinol) as compared to antibiotic therapy alone begun 72 hours after infection. Both were successful in eradicating the infection rapidly, but did not entirely prevent renal damage. Treatment prior to 72 hours thus is important. It appears that the combined treatment, designed to eradicate the bacteria as well as reduce the post-ischemic reperfusion damage and the phagocytic burst of phagocytosis is ideal, as this combined treatment was effective in preventing almost all renal damage and loss of renal function.  相似文献   
3.
Immunization with an inactivated whole-virus vaccine is highly effective in preventing lentivirus infection. The viral protein(s) essential to the induction of protective responses, however, have not been identified. To define the role of virion components in the induction of protective immunity, we evaluated the efficacy of glycoprotein-enriched and glycoprotein-depleted simian immunodeficiency virus (SIV) subunit vaccines prepared by lentil-lectin affinity chromatography of gradient-purified virions using the immunization and challenge regimen previously found successful with an inactivated whole-virus vaccine. Infection was determined by successful recovery of virus, the induction of SIV-specific antibody responses, and infection of naive recipients by inoculation with lymph-node-derived lymphocytes from the vaccinates. Immunization with the glycoprotein-enriched preparation prevented infection in two out of four monkeys, whereas the glycoprotein-depleted vaccine failed to prevent infection in all four vaccinates tested. However, the glycoprotein-depleted vaccine appeared to moderate the progression of SIV-induced disease compared with non-immunized infected control monkeys inoculated with the same challenge dose. These data suggest that subunit vaccines containing sufficient quantities of viral glycoproteins can protect against SIV infection, whereas subunit vaccines composed predominantly of viral core proteins cannot. The development of effective vaccines against HIV infection should include studies on the optimum presentation of the viral envelope glycoproteins to produce long-term broadly protective immune responses.  相似文献   
4.
目的 探索LDH实验检测细胞活力的可行性。方法 原代培养骨髓细胞和软骨细胞,用LDH实验测定上述两组细胞的活力,并与镜下活体观察到细胞的生长状况相比较。与目前比较成熟的测定细胞活力的MTS实验的测得的值相比较。结果 LDH实验对上述两组细胞的活力的测定结果与镜下活体观察到的结果相符合。与MTS实验的测得的结果经统计学处理无显著差异。结论 LDH实验可用于细胞活力的直接测定,而对活细胞的生存、繁殖无影响。  相似文献   
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Glutaurine (gamma-L-glutamyl taurine), a proposed hormone isolated from parathyroid gland oxyphil cells, was examined for its effect on circulating thyroid hormones in the rat. In acute experiments performed over a 24 hr. period, glutaurine depressed plasma triiodothyronine (T3) levels in a dose-dependent manner; however, thyroxine (T4) levels were not affected significantly. In chronic experiments performed over a 2 wk. period, glutaurine significantly increased T3 levels, but, as with acute studies, the effect of T4 levels was not significantly altered. Following acute glutaurine administration, TSH levels were elevated above control. The increased T3 observed following chronic glutaurine administration may be due to a secondary increase in TSH levels. These data support the hypothesis that glutaurine aids in peripheral thyroid hormonal regulation. Observed differences between acute and chronic glutaurine action are though to result from the effect of glutaurine on the negative feedback inhibiting action of TSH.  相似文献   
8.

Background  

Temporomandibular joint (TMJ) arthritis is frequently seen in children with chronic arthritis. It has rarely been described in a non-infectious acute setting. We report a case of reactive arthritis isolated to the TMJs and cervical spine.  相似文献   
9.
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that activating mutations in this receptor might cause autosomal dominant hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified, in two families with ADHP, heterozygous missense mutations in the Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of 50 normal controls had either mutation. We also identified a de novo, missense Ca(2+)-sensing receptor mutation in a child with severe sporadic hypoparathyroidism. The amino acid substitution in one ADHP family affected the N-terminal, extracellular domain of the receptor. The other mutations involved the transmembrane region. Unlike patients with acquired hypoparathyroidism, patients with these mutations had hypercalciuria even at low serum calcium concentrations. Their greater hypercalciuria presumably reflected activation of Ca(2+)-sensing receptors in kidney cells, where the receptor negatively regulates calcium reabsorption. This augmented hypercalciuria increases the risk of renal complications and thus has implications for the choice of therapy.   相似文献   
10.
Platelet-derived growth factor BB (PDGF BB) and the PDGF receptor b are expressed on mesotheliomacells, but their biological function has not yet been defined. In the present study we used Boyden chambersfitted with filters coated with the adhesive matrix proteins fibronectin, laminin, collagen type IV or the non-matrixadhesive molecule poly-L-lysine (PLL). Mesothelioma cells migrated towards PDGF BB at concen-trationsranging from 0.78 to 12.5 ng/ml if matrix proteins were present as adhesive substrates. This migrationwas integrin dependent since the same cells failed to migrate if the adhesive interactions necessary for migra-tionwere provided by molecules other than integrins. Migration of mesothelioma cells on fibronectin, lamininor collagen-type IV in response to PDGF BB was inhibited if the cells were pretreated with blocking anti-bodiesto a3b1 integrin. These findings describe for the first time PDGF BB as a chemoattractant for malig-nantmesothelioma cells and that collaboration between PDGF receptor b and integrin a3b1 is necessaryfor the motile response of these cells to PDGF BB.©Kluwer Academic Publishers  相似文献   
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