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91.
92.
To evaluate the pathogenetic roles of immune complexes and alveolar hyaline membrane in idiopathic interstitial pneumonia (IIP), immunohistological and ultrastructural studies of the kidney and lung were performed in 23 cases of IIP, 19 cases of autoimmune diseases, 17 cases of interstitial pneumonia other than IIP, and 11 cases of bronchopneumonia as a control group. None of the cases of IIP or interstitial pneumonia other than IIP showed immune complexes in the alveolar and glomerular capillary walls. On the other hand, one case of SLE was positive for IgG and components of complement along the alveolar and glomerular capillary walls. The alveolar hyaline membrane in the present cases revealed immunoglobulins as well as components of complement, which were poorly soluble in chaotropic solution or acidic buffer. These results indicate that circulating immune complexes play a minor role in the pathogenesis of IIP and other types of interstitial pneumonia, and that there is no relationship between immune complex deposition in alveoli and the alveolar hyaline membrane. It is necessary to further investigate factors other than immune complexes involved in alveolar tissue damage and to clarify the significance of the hyaline membrane in the processes occurring from acute changes to pulmonary fibrosis in IIP.  相似文献   
93.
太空发育鸡胚的前庭感受器细胞形态学研究   总被引:4,自引:0,他引:4  
为了探讨太空微重力对鸡胚前庭感觉上皮细胞的形态发育的影响 ,选取在航天飞机 (STS-2 9)发育鸡胚和地面发育鸡胚各两只 ,利用计算机显微测量技术分别测量椭圆囊和球囊的毛细胞、支持细胞核的切面面积、周长、形状系数。太空发育鸡胚的球囊支持细胞核的切面面积、周长显著大于地面组 ,形状系数无差异 ;太空发育鸡胚的椭圆囊支持细胞核的切面面积、周长、形状系数以及椭圆囊和球囊毛细胞的切面面积、周长与地面发育鸡胚相比无明显差异。微重力可能对球囊支持细胞核的体积发育有影响 ,对椭圆囊和球囊的毛细胞以及椭圆囊支持细胞核的形态发育无影响。  相似文献   
94.
A case of giant inflammatory polyposis associated with a localized inflammatory bowel disease of the descending colon in a 49-year-old man is presented. Lower abdominal distension rapidly appeared without any previous history of gastrointestinal disease. Two months later, he underwent a left hemicolectomy. Postoperative recovery was complete and he remains in good health more than 2 years later. The resected colon showed a giant and bizarre polyposis measuring up to 12 cm in length and 2 cm in height and covering the entire circumference of the colon. The polyposis consisted of narrow worm- or noodle-like polyps that bridged over the irregularly shaped ulcers, which sometimes extended into muscularis propria. Although longitudinal ulcers or scars, stricture, and a cobble-stone appearance were not observed, transmural inflammation and deep fissures were found in the interpolypoid area. From these findings, this case seems to be more similar to Crohn's disease than other inflammatory bowel diseases.  相似文献   
95.
BACKGROUND: The loop-mediated isothermal amplification (LAMP) method is a novel technique for the amplification of specific DNA sequences. OBJECTIVES: To establish the LAMP method for amplifying Epstein-Barr virus (EBV) DNA and to examine its reliability for the detection of EBV DNA in clinical specimens. STUDY DESIGN: Sera from 108 patients, who were initially suspected of primary EBV infection, were tested by the EBV LAMP method, and the results were compared with those of the real-time PCR assay. Serological examination was regarded as the standard diagnostic method. RESULTS: To diagnose primary EBV infection, the sensitivity of LAMP was 86.4% and the specificity was 100%. The sensitivity of the real-time PCR assay was 84.1% and the specificity was 98.4%. Longitudinal analysis showed that the detection rate of EBV DNA in serum by the LAMP method decreased with time in accordance with the decrease of the EBV load. EBV DNA could not be detected in serum 40 days after onset of symptoms. CONCLUSIONS: These results indicate that the sensitivity and specificity of the LAMP method are comparable to those of real-time PCR and that detecting EBV DNA in serum by this method is potentially useful for diagnosing primary EBV infection.  相似文献   
96.
Complementary DNAs to the 5 proximal region of the dengue virus type 3 RNA were cloned into bacterial plasmids and the nucleotide sequence of 3,000 bases from the 5 terminus of the genome were determined by DNA and RNA sequencing methods using dideoxy chain-termination reactions. Comparison of the nucleotide sequence thus obtained with those of other flavivirus genomes revealed significant homology existing in nucleotide sequence of the flavivirus genomes. When we compared amino acid sequence deduced from the nucleotide sequence with those of other flaviviruses, this genome region was found to include sequences encoding three viral structural proteins C, M, and E and a part of the viral nonstructural protein NS1 in this order in addition to the 5-noncoding sequence. The characteristics and functions of these proteins were discussed based on the deduced amino acid sequences and their hydrophobic profiles. The genetic relationship of flaviviruses was also discussed based on the genetic variation observed in their genomes.  相似文献   
97.
Fluconazole monotherapy for cryptococcosis in non-AIDS patients   总被引:3,自引:0,他引:3  
Treatment with 200 to 400 mg/day fluconazole was evaluated in 44 patients without AIDS who had cryptococcosis (19 with cryptococcal meningitis, 22 with pulmonary cryptococcosis, 3 with other cryptococcal infections). For all patients, the clinical response rate was 89% (48% were clinically cured and 41 % clinically improved). Of the patients with cryptococcal meningitis, 89% were mycologically cured. These rates are comparable to those obtained in the treatment of AIDS patients with cryptococcal disease. In the group of patients with cryptococcal meningitis, there was a high rate of agreement between the mycological response to therapy and cryptococcal antigen test results. The use of cryptococcal antigen testing is recommended in all patients with cryptococcosis.  相似文献   
98.
BACKGROUND: The yeast [PSI+] factor is transmitted by a prion mechanism involving self-propagating Sup35 aggregates. As with mammalian prions, a species barrier prevents prion transmission between yeast species. The N-terminal of Sup35 of Saccharomyces cerevisiae, necessary for [PSI+], contains two species-signature elements-a Gln/Asn-rich region (residues 1-41; designated NQ) that is followed by oligopeptide repeats (designated NR). RESULTS: In this study, we show that S. cerevisiae[PSI+] is transmissible through plasmid shuffling and cytoplasmic transfer to heterotypic Sup35s whose NQ is replaced with the S. cerevisiae NQ. In addition to homology, the N-terminal location is essential for NQ mediated susceptibility to [PSI+] transmission amongst heterotypic Sup35s. In vitro, a swap of NQ of S. cerevisiae Sup35 led to cross seeding of amyloid formation. CONCLUSIONS: These findings suggest that NQ discriminates self from non-self, and is sufficient to initiate [PSI+] transmission irrespective of whether NR is heterotypic. NR as well as NQ alone coalesces into existing [PSI+] aggregates, showing their independent potentials to interact with the identical sequence in the [PSI+] conformer. The role of NQ and NR in [PSI+] prion formation is discussed.  相似文献   
99.
Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials.  相似文献   
100.
A variety of pathological changes are seen in lymphoproliferative disorders of the lung but the histogenesis of these abnormalities is not yet fully understood. We previously showed that adenovirus vector-mediated transient expression of both the human interleukin-6 (IL-6) and IL-6 receptor (IL-6R) genes, but not the IL-6 gene alone, in the rat lung induced lymphocytic alveolitis. In the present study, we explored the lung pathology of human IL-6 and IL-6R double transgenic mice to elucidate the effects of prolonged IL-6 signalling on the lung. The transgenic animals developed mononuclear cell accumulation in peribronchovascular regions, but little infiltration into alveolar spaces. Immunohistochemical analysis revealed that the cellular accumulations contained not only mixtures of inflammatory cells but also lymphoid tissue-like structures. As the expression of CXCL13/BLC, the indispensable chemokine for lymphoid organogenesis, was recognized in the B cell follicles of the pulmonary lesions, we speculate that this chemokine plays an inductive role in the development of the lymphoid tissue-like structures. These structures were distinguished from bronchus-associated lymphoid tissues (BALTs) by their location and by the lack of lymphoepithelium, which is a characteristic of BALT. These findings imply that IL-6 signalling may play a role in the pathogenesis of lymphoproliferative disorders of the lung.  相似文献   
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