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101.
There are many reports showing a close relation between polyamine metabolism and tissue growth or recovery of damaged tissues, such as regenerating liver. Thus, changes in polyamine metabolism in the livers from rats treated with D-galactosamine, an inducer of experimental hepatitis, were studied. The activity of ornithine decarboxylase started to increase 14 hr after administration of galactosamine and reached 30 times the normal activity at about 25 hr, the time of maximum severity of hepatitis. The content of putrescine increased to about 10 times the control value. After increases in the putrescine content and ornithine decarboxylase activity, the hepatitis started to diminish. Increases in the activity of S-adenosylmethionine decarboxylase and the content of spermidine were observed 33-37 hr after administration of galactosamine. The maximum values of these parameters, which were significantly higher than the control values, were observed after the healing process had started.  相似文献   
102.
The stroke-prone spontaneously hypertensive rat (SHRSP) has been reported to show significantly lower levels of serum total cholesterol than the normotensive control strain Wistar-Kyoto rat (WKY). Because selective inbreeding was conducted for stroke proneness, this concomitantly inherited characteristic of SHRSP may play some pathophysiological role in stroke. We evaluated the genetic determinants of the cholesterol trait by estimating heritability and subsequently by undertaking a genome-wide screen with 161 genetic markers in F(2) progeny involving SHRSP and WKY (104 male and 106 female rats). Three quantitative trait loci (QTLs) were detected on rat chromosomes 5, 7, and 15. Markers from the linked region on chromosome 15 indicated significant evidence of linkage with a maximal log of the odds (LOD) score of 7.7, whereas those on chromosomes 5 and 7 cosegregated with the trait in a sex-specific manner (the QTL close to genetic marker D5 Mit5 reached an LOD score of 7.3 in males, and that close to D7 Mit10 reached an LOD score of 3.2 in females). The male-specific QTL on chromosome 5 appeared to overlap with previously reported QTLs for stroke-associated phenotypes, but an identical gene (or genes) appeared unlikely to control these and the cholesterol traits simultaneously. In the present study, serum cholesterol levels were shown to be highly genetically determined in SHRSP (the heritability estimates are 76% in males and 83% in females), and 3 QTLs with substantial effects were identified. Further work, however, is required to clarify whether the cholesterol trait is related to the etiology of stroke or has been retained by chance through the inbreeding process in SHRSP.  相似文献   
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Le Fort distraction osteogenesis is sometimes applied to improve the facial appearance in craniofacial dysostosis or cleft lip and palate. Distraction devices are generally classified into external and internal types. The movement of external distractors can be controlled easily but their large size and the need for a facial mask cause much psychological stress to the patient. Internal distractors are smaller and better tolerated, but they are not easily controllable and removal is difficult. We designed an internal distraction device to eliminate the problems of the currently available distractors -Nakajima's angle-variable internal distraction (NAVID) system - and aimed to assess its clinical applicability. Between 2000 and 2010, we treated 16 patients with the NAVID system: Le Fort I, III, III?+?I and IV distractions were performed in three, five, four and four patients, respectively. Distraction was started after a 1-week latency period. Then, the exposed rod was cut, and the distractors were left in place for 3 months or more as retention devices, and thereafter removed. All patients showed satisfactory occlusion and facial aesthetics. Open bite during the consolidation period was the main complication. In conclusion, the NAVID system is safe, effective and reliable for all types of Le Fort distraction osteogenesis.  相似文献   
107.
The morphological interactions between astroglial and neuronal elements were elucidated in the rat suprachiasmatic nucleus (SCN) by light and electron microscopic immunocytochemistry using antibodies against glial fibrillary acidic protein (GFAP), vasoactive intestinal peptide (VIP) and arginine-vasopressin (AVP). Throughout the SCN, particularly in its ventral portion, GFAP-like-immunoreactive (GFAP-LI) astroglial elements were found. These astrocytes displaying GFAP-like immunoreactivity occasionally contained fairly well-developed organelles. Some of these astrocytes were found as satellite cells in close contact with non-immunoreactive neuronal perikarya and processes. Around the neurons, GFAP-LI astroglial processes were also observed to cover some portions of presynaptic and postsynaptic elements. In addition, these astroglial elements were seen between two neuronal somata and pericytes of blood capillaries as glial endfeet. By double labeling immunoelectron microscopy using antibodies against GFAP/VIP and GFAP/AVP, some portions of VIP-like-immunoreactive or AVP-like-immunoreactive neuronal somata and processes were found to be engulfed by GFAP-LI astroglial processes. The possible functional roles of the morphological interactions between astroglial and neuronal elements are discussed.  相似文献   
108.
Surgically treated pulmonary inflammatory pseudotumor   总被引:3,自引:0,他引:3  
We report 2 cases diagnosed as so-called pulmonary inflammatory pseudotumor. In case 1, a 28-year-old man with a slow growing 6-cm pulmonary tumor who underwent a right upper lobectomy was diagnosed with an inflammatory myofibroblastic tumor. In case 2, a 55-year-old man with chest pain and cough, who underwent open lung biopsy was diagnosed with plasma cell granuloma. Despite both diagnoses being classified as pulmonary inflammatory pseudotumors, we believe they should be classified differently.  相似文献   
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In order to elucidate and characterize the transport pathway of the substances in the amniotic fluid, the permeability of the term human amnion was studied ultracytochemically, with lanthanum or horse radish peroxidase (HRP) as a tracer. Pieces of the term human amnion were exposed to the solutions containing lanthanum or HRP, and processed for electronmicroscopy. Precipitates indicating lanthanum or HRP were observed in the lateral intercellular spaces of the amniotic epithelial cells through the entire depth of the spaces. Generally, pinocytosis of HPR was not observed. In rare cases, however, diffuse uptake of HRP was noticed in the cells of the electron-lucent cytoplasm. These facts indicated that the human amniotic epithelium is quite permeable and that this particular intercellular pathway is important in the mechanism of the transfer of substances between the mother and the fetus.  相似文献   
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