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31.
A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. lmmunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CAl25, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoem-bryonic antigen, α-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin.  相似文献   
32.
Two temperature-sensitive mutants of WSN influenza virus, ts-61S and ts-134, possess defects in the hemagglutinin (HA) gene. These defects are characterized as a defective intracellular transport of the HA at the nonpermissive temperature and a marked thermolability. The nucleic acid sequences of the HA gene of these two viruses, as well as a series of revertant viruses, were determined. The deduced amino acid sequences demonstrate that the HA of ts-61S varied from the wild type protein by three amino acids while that of ts-134 differed by two residues. For both mutants, analysis of revertant viruses indicated that the phenotype of transport inhibition at the nonpermissive temperature and heat lability were associated with a single amino acid change in the globular portion of the molecule. In the case of ts-61S, the critical change in the HA was the replacement of a serine residue at position 110 with that of a proline. The mutational defect in the HA of ts-134 was due to the substitution of a tyrosine residue at position 159 with that of a histidine residue. Four of five revertants of ts-134 were suppressor revertants, of which some of the compensatory changes did not restore thermostability to the HA.  相似文献   
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Summary We have compared the kinetic growth patterns of To-336, MEQ11, KRT, and SK2 rubella vaccine strains licensed in Japan at 37° and 39° C with those of progenitor wild strains of rubella virus. The growth of vaccine strains was depressed at 39° C to a level about 3 log10 lower than that at 37° C. The difference in virus titer attained by wild strains at 37° and 39° C was less than tenfold. The growth potential at 39° C paralleled the immunogenic marker of rubella virus,i.e. the capability of virus to induce antibody response upon subcutaneous injection in rabbits for all wild and vaccine strains examined, including one strain at an intermediate level of attenuation. Several clones were isolated from the progeny produced by a vaccine strain during the growth at 39° C. Among them were partial revertants in immunogenic marker as well as in the growth potential at 39° C. It was concluded that the immunogenic marker of rubella virus in rabbits represented its capability to replicate at the body temperature of the animal.With 6 Figures  相似文献   
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36.
We reported a 4-month-old girl with biotin deficiency caused by amino acid formula. Two weeks after birth, she was diagnosed as having a milk protein allergy. After switching to amino acid formula from usual formula, her symptoms and laboratory findings became normal. About three weeks after the beginning of amino acid formula, she developed intractable skin erosions around the eyes, mouth, neck, and anogenital area. By measuring concentrations of some trace elements, she was diagnosed as having a biotin deficit, because of the organic aciduria and undetectable serum biotin concentration. Her serum biotinidase level was normal. Upon administration of oral biotin supplementation, all her symptoms and laboratory findings were dramatically improved. Since amino acid formula contains very few biotin, we should pay attention to biotin deficiency when infants receiving amino acid formula.  相似文献   
37.
Gangliosides, a family of glycosphingolipids that contain sialic acid, are abundant on the neuronal cell membranes, but their precise functions in the central nervous system remain largely undefined. In a previous study of GalNAc-T(-/-) mice engineered to lack beta1,4-N-acetylgalactos-aminyltransferase (GM2/GD2 synthase) to abolish any, complex gangliosides, we observed the reduction of nerve conduction velocity but did not find any obvious morphological change in the brain. In the present study, we observed morphological changes in the nerve fiber tracts of the spinal cord in these mice. In GalNAc-T(-/-) mice, the number of degenerated axons was markedly increased in the dorsal funiculus, tract of Lissauer, and dorsolateral funiculus of the cervical segment of the spinal cord as well as the dorsal funiculus and tract of Lissauer of the lumbar segment of the spinal cord. There were also increased numbers of unmyelinated fibers in GalNAc-T(-/-) mice. Loosened myelin sheaths and myelin sheaths separated from axons by wide spaces were also observed in GalNAc-T(-/-) mice. These results provide a morphological basis for the previously observed reduction in the nerve conduction velocity and suggest that complex gangliosides are essential for the maintenance of myelin and the integrity of nerve fibers of the spinal cord.  相似文献   
38.
This study investigated the effects of repeated exposures to male and female targets on trait impressions and the role of stereotyped knowledge for the target's social category in impression formation process. The participants were repeatedly exposed to slides of male and female faces for subliminal durations. For each of 12 pairs containing both previously presented slide and newly presented slide, the participants made forced-choice liking judgments (Experiment 1), trait judgments (Experiment 2) and recognition judgments (Experiments 1 and 2). It was found that participants' attitude toward the targets became more positive, even though target recognition was not significantly greater than the chance level. Yet, when the dimension of judgment was stereotypically associated with the target's social category, exposure effects were obtained for the targets whose social category and its dimension were inferentially matched, but not obtained for the targets whose social category and its dimension were not inferentially matched. Some theoretical implications of the role of social category information in the mere exposure phenomenon are discussed.  相似文献   
39.
The present study was performed to examine changes in the arrangement of D-periodic collagen fibrils in the synovium of the growing temporomandibular joint in mice. At 1 week of age, the mandibular condyle was undeveloped, and only a few collagen fibrils were recognizable in the subintimal layer of the synovium. At 8 weeks, the mandibular condyle was structurally developed with an increase of collagen fibrils in the synovium; a fully mature condyle was observed at 6 months of age. The close association of proteoglycans with collagen fibrils in the synovium of the growing joint was examined by both conventional and energy-filtering transmission electron microscopy of cupromeronic blue-stained specimens. Proteoglycans were associated with D-periodic collagen fibrils in the short filamentous form in random fashion at 1 week of age, but in a regular pattern with D-periodicity at 6 months. These associations in the synovium could be correlated with the mechanical character of the temporomandibular joint.  相似文献   
40.
A 42-year-old Japanese male, who had been suffering from congestive heart failure and electrocardiographic abnormalities (A-V block, intraventricular conduction disturbance, ventricular tachycardia), died after a clinical course of 2 years and 1 month. Macroscopic investigation revealed dilation of the left ventricle and thickening of the right ventricular wall. The unique finding in this case was a circumferential fibrous scar in the median circular layer and outer oblique layer of the left ventricular wall. Biopsy and autopsy materials revealed diffuse loss of myofibrils in the central zone of cardiac muscle fibers, and replacement with aniline blue-positive homogeneous material (17-35% of the area of one muscle fiber). Electron microscopy revealed abnormal accumulation of fine filamentous material (7.5-25 nm in diameter), which was immunohistochemically proved to be desmin-type intermediate filament. Moreover, sarcoplasmic reticulum-like material was detected in the degenerated area. At autopsy, degeneration was detected all over the heart. The ventricular muscle fibers were more severely affected than the atrial muscle fibers. The conduction system was also affected, in some parts more severely than the surrounding ordinary muscle fibers. The pathogenesis of this disorder remains to be clarified.  相似文献   
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