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991.
The prevalence of MHL in 202, 1 to 6 year-old children with communication disorders who visited our clinic in 1991 was investigated. 1) 31% of the subjects had MHL bilaterally. The prevalence of MHL was 44% at age 1 year, 20% at age 2 years, 36% at age 3 years, 24% at age 4 years, 39% at age 5 years, 33% at age 6 years. 2) 88% of children with MHL had OME, 10% had mild sensorineural hearing loss, and 2% had cerminous plug. 3) The prevalence of MHL in children with mental retardation and autistic disorders was 9%, that with stuttering was 9%, that of OME accompanied by moderate and severe hearing disorders was 6%. 4) The primary causes in 191, except for those with stuttering, were as follows; the prevalence of MHL was 30%, that of mental retardation and autistic disorders was 24%, and that of articulation disorders was 28%. 5) On the other hand, the prevalence of MHL in children with retarded language development and articulation disorders was 30%, which was significantly higher than that of the other communication disorders. Accordingly, the results of this study suggest that MHL in early childhood greatly influences communication disorders.  相似文献   
992.
993.
A 35-year-old male patient clinically characterized by massive proteinuria and hypertension without evidence of systemic diseases is reported. Histological investigation of renal biopsy specimens revealed extensive nodular formations in the mesangial areas in every glomerulus. Light-microscopic examination did not allow discrimination between the glomerular changes found in these specimens and the nodular glomerulosclerosis described in patients with diabetes mellitus. Electron-microscopic examination confirmed the presence of massive, nodular, mesangial expansions consisting of finely fibrillar substances without electron-dense deposits and circumferential mesangial interposition. Immunofluorescent examination showed deposition of IgG, C3, fibrinogen and kappa and lambda light chains in mesangial areas, peripheral capillary loops and a part of the nodules. Furthermore, collagen types IV, V, VI and laminin were detected in the nodules. Amyloid was not observed in these nodules. This diagnosis has not been made, and the mechanism of this nodular glomerulosclerosis remains unknown.  相似文献   
994.
Atlantoaxial transarticular fixation is a proven stabilization technique used to augment conventional sublaminar fusion. Along with its superior biomechanical profile comes the inherent risk of neurovascular injury and potential compromised fixation during its application. This article presents a detailed systematic guide to this procedure including preoperative evaluation, positioning, and the more subtle aspects of the surgical technique. A new instrumentation design that has enhanced the ease and accuracy of screw placement with less operative frustration and potential morbidity of previous systems also is presented.  相似文献   
995.
BACKGROUND: This study characterized the phenotypic subsets of isolated gastric lymphocytes and the cellular immune response in cultured gastric biopsy specimens. METHODS: Endoscopy specimens from 40 Helicobacter pylori-positive and 40 H. pylori-negative patients were studied. a) Isolated gastric lymphocytes were analysed for CD4+, CD8+ T-lymphocyte subsets, activated T cells, and natural killer cells on a fluorescence-activated cell sorter, using monoclonal antibodies. b) The supernatant of cultured gastric biopsy specimens were assayed for interleukin (IL)-2, IL-4, and IL-6 levels. RESULTS: In H. pylori-positive patients there was (a) a decrease in CD4+/CD8+ T cells, no change in activated T cells, and an increase in natural killer cells, and (b) no change in IL-2 levels and a significant increase in IL-4 and IL-6 levels. CONCLUSIONS: There is an increase in CD8+ lymphocytes and natural killer cells, and the observed increase in IL-4 and IL-6 might be important in H. pylori-associated gastritis.  相似文献   
996.
After administration of CTP-11, a camptothecin derivative exhibiting a wide spectrum of antitumor activity, dose-limiting gastrointestinal toxicity with great interpatient variability is observed. Because the biliary excretion is a major elimination pathway for CPT-11 and its metabolites [an active metabolite, 7-ethyl-10-hydroxy-camptothecin (SN-38), and its glucuronide, SN38-Glu], several hypotheses for the toxicity involve biliary excretion. Here, we investigated whether primary active transport is involved in the biliary excretion of anionic forms of CPT-11 and its metabolites in humans using bile canalicular membrane vesicles (cMVs). Uptake of the carboxylate form of CPT-11 and the carboxylate and lactone forms of SN38-Glu by cMVs prepared from five human liver samples was ATP dependent. The concentration dependence of the ATP-dependent uptake of the carboxylate form of CPT-11 and SN38-Glu suggests the involvement of at least two saturable transport components, both with lower affinity and higher capacity than in rats. The ATP-dependent uptake of the carboxylate form of SN-38 showed a single saturable component but was detectable only in one human cMV sample. Both carboxylate and lactone forms of SN38-Glu uptake also showed a large intersample variability, although the variability was less than that observed for the carboxylate form of SN-38. On the other hand, the carboxylate form of CPT-11 exhibited much less variability. The carboxylate forms of SN38-Glu and SN-38 almost completely inhibited the ATP-dependent uptake of leukotriene C4, a well-known substrate of canalicular multispecific organic anion transporter, whereas the inhibition by the carboxylate form of CPT-11 was not as marked. Thus, multiple primary active transport systems are responsible for the biliary excretion of CPT-11 and its metabolites, and the major transport system for CPT-11 differs from that for the other two compounds. A greater degree of inter-cMV variability in the uptake of SN-38 and SN38-Glu may imply that interindividual variability in biliary excretion of these metabolites might contribute to interpatient variability in the toxicity caused by CPT-11.  相似文献   
997.
998.
A new vectorial finite-element method for the analysis of dielectric waveguide problems is formulated in terms of all three components of the magnetic field H. In this approach, the relation div H = 0 is satisfied and the spurious non-physical solutions do not appear.  相似文献   
999.
A 1-Mb (256 K×4 b) CMOS static random-access memory with a high-resistivity load cell was developed with 0.7-μm CMOS process technology. This SRAM achieved a high-speed access of 18 ns. The SRAM uses a three-phase back-bias generator, a bus level-equalizing circuit and a four-stage sense amplifier. A small 4.8×8.5-μm2 cell was realized by the use of a triple-polysilicon structure. The grounded second-polysilicon layer increases cell capacitance and suppresses α-particle-induced soft errors. The chip size measures 7.5×12 mm2  相似文献   
1000.
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