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61.
62.
We report three cases of fundic gland polyposis in the stomach identified in three patients who were related. Grossly the numerous polyps covered an area limited to the body and fundus of the stomach, no polyps were found in the antrum, duodenum, colon, or rectum, and histologically, the gastric lesions consisted of numerous hamartomatous polyps, characterized by proliferation of the fundic and cystic glands. The gastric lesions were identified in families without polyposis coli. This type of fundic gland polyposis has never been documented before in the literature.  相似文献   
63.
The expression of heat shock protein 25 (Hsp 25) was investigated in the rat temporomandibular joint by immunocytochemistry combined with confocal and electron microscopy. Immunostaining with an antibody to Hsp25 was able to demonstrate various cellular elements in the synovial membrane of the joint. Intense immunoreaction for Hsp25 was recognized in certain cells comprising the synovial lining layer. Confocal microscopic observation revealed two characteristic profiles of the Hsp25-positive cells with cytoplasmic processes: one extended thick and long processes towards the articular cavity, and the other prejected horizontally slender processes which covered the synovial membrane. Under the electron microscope, the immunoreactive synovial lining cells were characterized by a well-developed rough endoplasmic reticulum and secretory granules, suggesting that they can be categorized as fibroblastic type B cells. The covering by the cytoplasmic extensions was confirmed by immuno-electron microscopic observations. This cytoplasmic covering presumably performs a barrier function and expedites the effective secretion/resorption of synovial fluids. Since it has been proposed that Hsp 25 is associated with an estrogen receptor, the immunopositive synovial lining cells were considered estrogen-target cells. Immunoreactivity for Hsp25 was also observed in the chondrocytes of the maturative and hypertrophic cell layers as well as in the cells of the articular disk. A suggestion was made that Hsp25 might be involved in the inhibition of apoptosis of those cells.  相似文献   
64.
Legionellosis     
Although increasing attention is being given to Legionella pneumonia in Japan, reports of solitary onset of this disease are scant in Japan. The patient, from whom L. dumoffii was isolated, was a 59-year-old male with no underlying disease. He visited our hospital because of fever and cough, and was admitted to our department for X-ray findings consistent with pneumonia. After admission, pulmonary lesions spread rapidly, and based on the suspicion of Legionella pneumonia, drugs such as EM, RFP and MINO were used. However, the patient died on the 26th hospital day. L. dumoffii was isolated from specimens obtained by airway aspiration before death and specimens of lung abscess and airway discharge obtained during autopsy (7 specimens in total). In addition, the L. dumoffii antibody titer in the serum became elevated. This is the first case of L. dumoffii pneumonia reported in Japan. The other case was in an 81-year-old male with underlying disease. He was admitted urgently with suspected pneumonia but died on the following day. L. pneumophila serogroup 5 was isolated from autopsied lung tissue. Fatality is high for this disease, making early diagnosis and treatment with appropriate antibiotics essential. Physicians should bear in mind the possibility of this disease and request the necessary laboratory tests in suspected cases without delay.  相似文献   
65.
In order to investigate anthracosis of the human lung, especially its causal relationship with atmospheric pollution and the occurrence of lung cancer, intrapulmonary particulate pollutants (IPP) from autopsy cases and patients lobectomized because of lung cancer were separated by alkali digestion of the lung tissue, and their elemental constitution was analyzed by a wavelength-dispersive X-ray fluorescence spectrometer. Silicon was the most abundant mineral constituent of non-carbonaceous fraction of IPP, followed by calcium, magnesium, iron, aluminum and other trace elements. The levels of silicon and aluminum in IPP were significantly higher in individuals treated at Saitama Medical School Hospital than in those from Tokyo. Farmers showed higher levels of silicon and aluminum than other occupational categories, whereas male blue-collar workers showed higher levels of calcium and lead than farmers. The level of iron in IPP of male smokers tended to be higher than in non-smokers. In cases of lung cancer, especially of the hilar type, the levels of iron, calcium, copper, lead, chromium and nickel in IPP tended to be higher than in non-lung cancer cases, whereas the levels of silicon and aluminum were lower than in non-lung cancer cases. On the basis of these results, pulmonary anthracosis was considered to be etiologically related to the occurrence of lung cancer.  相似文献   
66.
Summary: The polycondensation of 1‐ethynyl‐2,5‐dihexyl‐4‐iodobenzene in the presence of 1‐ethynyl‐2,5‐dihexyl‐4‐(2‐phenylethynyl)benzene proceeds according to the mechanism of initiated chain growth polycondensation. It has allowed the synthesis of oligomers with a desired molecular weight and a narrow molecular weight distribution. The reasons for the side reaction leading to the formation of diyne compounds are revealed and the presumed mechanism is given. This opens prospects for the preparation of defectless poly(p‐phenyleneethynylene)s with required molecular weights and narrow molecular weight distributions.

  相似文献   

67.
We synthesized 46 sequential peptides 21 to 39 amino acids long over the structural protein of human T-cell leukemia virus type I (HTLV-I; the p19 and p24 gag protein and the gp46 and p20E env proteins) and tested their reactivities against antibodies in sera from HTLV-I healthy carriers and patients diagnosed as having human T-cell leukemia-lymphoma (ATLL) and myelopathy (HAM) by using an enzyme-linked immunosorbent assay. Of the 46 synthetic peptides, 18 peptides (2 corresponding to the p19 gag protein, 2 corresponding to the p24 gag protein, 8 corresponding to the gp46 env protein, and 6 corresponding to the p20E env protein) reacted with antibodies in the sera from HTLV-I healthy carriers. In particular, the peptides comprising amino acids 100 to 119 and 119 to 130 of the gag and 175 to 199, 213 to 236, 253 to 282, and 288 to 317 of the env proteins reacted with antibodies in sera from more than 30% of HTLV-I healthy carriers. These peptides also showed high reactivities to the antibodies in the sera from patients with ATLL and HAM. The results indicate that the predominant antigenic regions of the structural protein of HTLV-I were located at the C-terminal end of the p19 gag protein and the C-terminal half of the gp46 env protein, and the corresponding peptides proved to be useful antigens in detecting antibodies in the sera from individuals infected with HTLV-I.  相似文献   
68.
Using 2-dimensional electrophoresis and ion-pair chromatography, we have identified elements of proliferating cell nuclear antigen (PCNA) multiprotein complexes that are reactive to antibodies in sera from patients with systemic lupus erythematosus. Among the various elements of the complexes, a 37 kDa protein (PI 8.5) that specifically reacted with SLE sera, but not with sera from patients with other connective tissue diseases, was identified as glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Immunoblot analysis showed that SLE sera reactive with the 37 kDa protein specifically reacted with GAPDH, as did anti-GAPDH mAbs. The purified autoantibodies to GAPDH from lupus serum showed both nuclear speckled and cytoplasmic staining patterns in immunofluorescence on Hep-2 cells. In addition, enzyme-linked immunosorbent assay (ELISA) revealed the presence of anti-GAPDH autoantibodies in 47% of lupus patients. Longitudinal analysis of the reactivity of lupus sera to PCNA complexes showed the autoimmune response to spread from GAPDH to other elements of PCNA complexes, and the presence of anti-GAPDH antibodies was significantly correlated with increased levels of serum PCNA. Taken together, these findings suggest that GAPDH interacting with PCNA in association with its cellular function is a novel autoantigen recognized by lupus sera, and that GAPDH thus plays an important role in the induction of autoimmune responses against the PCNA complex.  相似文献   
69.
Hepatitis B virus (HBV), with a G-to-A point mutation at nucleotide 83 in the precore region (mutant HBV83), accounts for most cases of hepatitis B e antigen (HBeAg)-defective HBV. However, it is still not clear how mutant HBV83 is associated with HBe seroconversion. Twenty-six HBeAgpositive patients with chronic hepatitis B who received oral prednisolone (30 mg/day) for 3 weeks were studied to clarify the prevalence of mutant HBV83 during the treatment using polymerase chain reaction with a restriction fragment length polymorphism assay. Twelve (46%) patients seroconverted to anti-HBe 1 year after treatment, whereas 14 (54%) did not. The proportion of mutant HBV83 to whole HBV remained unchanged in both groups during an acute exacerbation induced by withdrawal of corticosteroids. Among 12 anti-HBe-0seroconverted patients, five (56%) of nine patients with only wild-type HBV at baseline developed detectable levels of mutant HBV83 while all three patients with a mixed viral population of wild-type HBV and mu tant HBV83 at baseline developed a higher pro portion of mutant HBV83 one year after treat ment. In contrast, these changes were observed in only one (14%) of seven who failed to seroconvert. The results indicate that a flare-up of hepa titis precedes emergence or selection of mutant HBV83, followed by HBe seroconversion in patients with chronic hepatitis B. © 1995 WiIey-Liss, Inc.  相似文献   
70.
Light and electron microscopic studies have been made on an anaplastic giant-cell tumor that developed in a woman 8 years after an operation on the thyroid for papillary carcinoma. Many giant cells were observed in the anaplastic tumor tissue, but no follicles. Numerous tightly-packed mitochondria and abundant ribosomes were present, but there were no desmosomes. The basement membrane was not distinct.  相似文献   
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