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991.
Kikuchi-Fujimoto disease (KFD) is a rare cause of cervical lymphadenitis which mostly affects Asian women but is sometimes observed in the pediatric population. This study analyzed the clinical manifestations and disease course in children with KFD. Retrospective chart review and telephone interview were used to collect data for 13 children (8 boys and 5 girls) with a diagnosis of KFD from January 1988 to January 2003. Involvement of the posterior cervical lymph nodes was found in 12 patients, leukopenia in 9, and all patients had C-reactive protein less than 5 mg/dL. A high antinuclear antibody titer was associated with a more protracted and complicated course. Five of the 13 patients had new symptoms compatible with an autoimmune process during follow-up, with neurological symptoms the most common. In conclusion, the risk of evolution into an autoimmune syndrome in pediatric KFD patients is high, and careful long-term observation is mandatory.  相似文献   
992.
The extent of population diversity among GB virus C (GBV-C)/hepatitis G virus (HGV) within a persistently infected individual (Iw) was investigated by sequence analysis of multiple clones generated from polymerase chain reaction (PCR)-amplified products of cDNA analogous to fragments of 5 non-coding region (5NC), envelope region 1/2 (E1/E2) and non-structural region 3 (NS3) of viral genome. Although nucleotide substitutions were more common in coding regions than in the 5NC region, there was no region corresponding to the hypervariable region of hepatitis C virus in the E1/E2 region. Transition substitution exceeded transversion by 7 to 12-fold, and 79.4% of substitutions were synonymous. This bias against substitutions producing amino acid replacements and the use of Pfu DNA polymerase with an error rate 10 times lower than the observed frequency of substitution, suggests that most substitutions were not artefactual. This data suggests that individual genomes of HGV within an infected individual may differ from each other at 0.23–0.84% nucleotide position and at 0.42–0.61% amino acid position.  相似文献   
993.
Hydrothermal method was used to prepare the hydroxyapatite (HA) coating on CaO-SiO2-B2O3-Na2O glass. The phase composition, morphology and microstructure of HA coated glass composites were analyzed using XRD, EPMA, FT-IR and SEM techniques. It revealed that HA coating possessed a porous gradient construction; HA coating was tightly bonded with the glass substrate by the interface layer. During the formation of HA coating, the hydrated silica produced by the corrosion of glass substrate in the hydrothermal solution provided favorable sites for apatite nucleation. With the dissolving of HA powder and the growth of apatite small crystallites, Ca+, PO(4 (3-)) ions would precipitate on the surface of glass to form the HA coating. Silicon element released from glass reacted with calcium produced by the dissolution of HA to form the tight reaction layer. HA coating is formed by the mechanism of dissolving-ions immigrating-precipitating pattern.  相似文献   
994.
We report here the molecular cloning of a newly identified preprotachykinin gene, Pptc, which specifies the sequence for a new preprotachykinin protein and bioactive peptide designated hemokinin 1 (HK-1). PPT-C mRNA was detected primarily in hematopoietic cells in contrast to the previously described Ppta and Pptb genes, which are predominantly expressed in neuronal tissues. HK-1 has several biological activities that are similar to the most studied tachykinin, substance P, such as induction of plasma extravasation and mast cell degranulation. However, HK-1 also has properties that are indicative of a critical role in mouse B cell development. HK-1 stimulated the proliferation of interleukin 7-expanded B cell precursors, whereas substance P had no effect. HK-1, but not substance P, promoted the survival of freshly isolated bone marrow B lineage cells or cultured, lipopolysaccharide-stimulated pre-B cells. N-acetyl-L-trytophan-3,5-bistrifluromethyl benzyl ester, a tachykinin receptor antagonist, increased apoptosis of these cells and in vivo administration of this antagonist led to specific reductions of the B220lowCD43 population (the pre-B cell compartment) in the bone marrow and the IgMhighIgDlow population (the newly generated B cells) in the spleen. Thus, HK-1 may be an autocrine factor that is important for the survival of B cell precursors at a critical phase of development.  相似文献   
995.
The shal gene encoding the transient potassium current, I A, plays important roles in shaping the firing properties of neurons in the pyloric network in the stomatogastric ganglion (STG) of the spiny lobster, Panulirus interruptus. However, when we overexpressed the shal protein in pyloric dilator (PD) neurons, the effect of increased I A was compensated by a parallel upregulation of the hyperpolarization activated inward current (I h). In an attempt to temporally separate the overexpression of shal from the compensatory up-regulation of I h channels, we inserted an endoplasmic reticulum (ER) export signal sequence, FCYENE, into the shal gene. This signal sequence accelerated the surface expression of shal protein in Xenopus oocytes and PD neurons. However, the accelerated expression of shal still did not alter the firing properties of the injected neuron, suggesting that the compensatory upregulation of I h occurs simultaneously with the upregulation of I A.  相似文献   
996.
Hyperimmunoglobulin E syndrome is a primary immunodeficiency disease characterized by markedly high titers of serum immunoglobulin E (IgE), chronic eczema, recurrent staphylococcal infections, pneumatoceles, reduced neutrophil chemotaxis, and variable impaired T cell function. There are no clinical tools for diagnosis and definitive laboratory investigation. Variability of presentation makes it easy to confuse the diagnosis with that of severe atopy or other rare immunodeficiencies. We report a case of a 6-year-old boy with hyperimmunoglobulin E syndrome with recurrent methicillin-resistant Staphylococcus aureus furunculosis. Physical examination revealed a peculiar facial appearance, pruritic dermatitis, and furunculosis over the scalp, neck, and back. Laboratory investigation revealed mild leukocytosis with eosinophilia, a very high immunoglobulin E level, defective neutrophil chemotaxis, and impaired lymphocyte proliferation to anti-CD3/CD28 monoclonal antibodies. The boy was discharged without incident after 2 weeks of antibiotic therapy and debridement.  相似文献   
997.
Spontaneous acute tumor lysis syndrome with advanced gastric cancer   总被引:3,自引:0,他引:3  
Acute tumor lysis syndrome (TLS) occurs frequently in hematologic malignancies such as high-grade lymphomas and acute leukemia, which are rapidly proliferating and chemosensitive tumors. It occurs rarely in solid tumors and has never been reported in gastric adenocarcinoma. Typical biochemical findings of acute tumor lysis syndrome are hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia in patients with a malignancy. Rapid changes of these electrolytes may cause cardiac arrhythmia, seizure, acute renal failure and sudden death. Therefore, as soon as it is detected, it should be taken care of immediately. Until now almost all cases of TLS associated with solid tumor have developed after cytoreductive therapy in chemosensitive tumors. We report here a case of spontaneous acute tumor lysis in a patient of advanced gastric cancer with hepatic metastases and multiple lymphadenopathy. The biochemical finding of TLS improved with the management and tumor burden also showed slight response to the one cycled combination chemotherapy but the patient died of progressive pneumonia.  相似文献   
998.
B H Wen  S R Yu  G Q Yu  Q J Li  X Zhang 《Acta virologica》1991,35(6):538-544
Four Coxiella burnetii isolates in China and two reference strains were compared by SDS-PAGE and immunoblotting. The SDS-PAGE profiles of whole cells and LPS of Chinese isolates Qiyi, Xinqiao, and YS-8 were found closely related to Henzerling strain, and different from the Grita strain. In immunoblot assay of LPS and proteinase K-digested whole rickettsiae minor differences were seen in polysaccharide structure among the Chinese isolates by phase I monoclonal antibody. The present results suggest that the strains reported here may be divided into three groups according to the polysaccharide structure: Xinqiao and Henzerling strains (1), YS-8 and Grita (2), and Qiyi (3).  相似文献   
999.
1000.
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