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71.
Two cases of disseminated infection caused by Mycobacterium intracellulare were reported and discussed. In the first case, the patient was a fifty-seven-year-old male who complained of general fatigue, weight loss, and fever. Biopsy of the right inguinal lymph nodes and the liver revealed infiltration by histiocytes engulfing many acid-fast bacilli. At autopsy an egg-sized abscess was found is the region of the right Iliac lymph nodes. Histological examination showed histiocytic infiltration in the abscess wall, neighboring lymph nodes, liver, and spleen. In the second case, the patient was a four-year-old boy, who had persistent fever and splenomegaly. Splenectomy was performed and histological examination of the spleen revealed multiple nodular infiltration by swollen histiocytes with many acid-fast bacilli in their cytoplasm. The bone marrow aspirates and liver tissue obtained in the necropsy also showed many histiocytes containing many acid-fast bacilli. The authors emphasized the importance of paying special attention to atypical mycobacteriosis in feverish patients having lesions with a proliferation of histiocytes.  相似文献   
72.
BACKGROUND: Manual puncture of the trophectoderm of human blastocysts with a needle before vitrification increases their survival rate, but the embryos take a long time to re-expand. This study examined whether causing human blastocysts to collapse by manual pipetting before vitrification would allow more rapid re-expansion and improve pregnancy rates. METHODS: After embryo transfer in IVF cycles, surplus embryos that developed to the expanded blastocyst stage were placed in cryoprotectant and then artificially shrunk by mechanical pipetting with a fine hand-drawn glass pipette slightly smaller in diameter than the blastocyst. The shrunken embryos were placed in a small volume of vitrification solution and plunged into liquid nitrogen on a cryotop. The blastocysts were thawed by warming and then dilution in 1 mol/l sucrose. RESULTS: Of 49 expanded vitrified blastocysts, 48 (98%) re-expanded within 3 h after warming. Following transfer (48 blastocysts in 28 cycles), 14 women (50%) became clinically pregnant, and the implantation rate was 33% (16/48). Eight healthy babies have been born in six deliveries, and the other eight pregnancies are ongoing. To date, there have been no spontaneous abortions. CONCLUSIONS: The results suggest that artificial shrinkage with pipetting is a simple and effective technique to assist successful cryopreservation of expanded blastocysts by vitrification.  相似文献   
73.
74.
The polymerization of methyl methacrylate (MMA) initiated by azoisobutyronitrile (AIBN) in the presence of various metal chlorides and water was investigated in N,N-dimethylformamide (DMF). The order of catalytic activity of the metal chlorides for the polymerization of MMA is as follows: A complex formation between poly(methyl methacrylate) (PMMA) and the metal ions was observed from the measurement of the solution viscosity of PMMA in the presence of the same metal ions in DMF.  相似文献   
75.
Two autopsy cases of leiomyosarcoma of the liver in a 49-year old female and 63-year-old male are reported. Both of the liver tumors showed electron microscopically dense patches in the cytoplasm and intermediate junctions between the tumor cells, suggesting a smooth muscle cell origin, irrespective of their different histological features. The nature of both tumors was confirmed by positive immunoreactivity for muscle-specific actin in the tumor cells, whereas desmin immunoreactivity was labile in both cases, showing a higher diagnostic value of the former compared with the latter in these leiomyosarcomas. Both cases, showed extensive distant metastases in spite of an evident difference in their mitotic indices, indicating that this index is not reliable for judging the metastatic potential of these tumors. Acta Pathol Jpn 41: 461–465, 1991.  相似文献   
76.
A study was made of the polymerization of acrylonitrile in dimethylformamide (DMF) initiated by the binary systems of tetramethyltetrazene (TMT) and p-substituted benzyl chlorides. The polymerization rate increased linearly with the σ-constants of substituents as electron-releasing groups were introduced to the phenyl ring of benzyl chloride. In order to elucidate the initiation mechanism of the polymerization, a kinetic investigation was also undertaken of the decomposition of TMT in the presence of p-substituted benzyl chlorides in DMF. The decomposition rate was first-order in TMT and first-order in p-substituents benzyl chloride. The decomposition rate also increased with the σ constants of substituents as electron-releasing groups were introduced. On the basis of the results, the initiation mechanism for the polymerization was discussed.  相似文献   
77.
Growing evidence suggests that the polymorphism of DNA base excision repair gene XRCC1 Arg399Gln is associated with altered DNA repair proficiency and subsequent cancer susceptibility; however, no evidence is available for malignant lymphoma. We therefore conducted a case-control study (372 cases, 500 controls) to evaluate links with malignant lymphoma risk in Japan. The risk was evaluated in terms of odds ratio (OR) and 95% confidence interval (CI) adjusted for age and sex in an unconditional logistic regression model. There was no statistical risk change with the Arg/Gln (adjusted OR 0.89; 0.65-1.23, P = 0.492) or the Gln/Gln (0.57; 0.27-1.17, P = 0.127) compared with the Arg/Arg of the XRCC1 Arg399Gln polymorphism. The results were unchanged in analyses according to histological subtype (diffuse large lymphoma, follicular lymphoma, low-grade lymphoma of mucosa-associated lymphoid tissue, and others). These data suggest that XRCC1 Gln399Arg polymorphism plays a limited role in lymphomagenesis. Further study on the interaction between the polymorphism and environmental exposure is required.  相似文献   
78.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
79.
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis.  相似文献   
80.
This is the first study of micro-autoradiography (micro-ARG) for [18F]2-fluoro-2-deoxy- -glucose ([18F]FDG). The localization of [18F]FDG was demonstrated in dendrites of neuron and also in the myelinated axon in mouse normal brain in vivo. The nucleolus was relatively free of label. The counted silver grain numbers in autoradiogram were linearly correlated to the 18F radioactivities in the specimen. The micro-ARG using positron emitting 18F is a very time-saving technique with 4 hours exposure compared with the conventional method using 3H- or 14C-labeled tracers.  相似文献   
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