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51.
52.
Thirty-two cases of congenital arachnoid cyst (AC), 26 cases of supratentorial, and 6 cases of infratentorial cyst are reported. They were encountered over a period of 9 years. The 26 supratentorial cysts consisted of 21 cases located in the middle fossa, 2 in the frontal, and 3 in the suprasellar. Patients' ages ranged from 7 months to 67 years (mean: 19.3 years), with a male to female ratio of 23:9. The most common symptoms were headache, epileptic seizure, and cranial enlargement. Based on observations between neuroradiological examinations including analysis of the cyst content, and operation, typical AC might be defined as "duplicated arachnoid and its splitting", and it may be said that "there is continuous existence of cerebral structure such as cortex and white matter lying adjacent to AC on MRI". Out of 32 cases, 15 received surgical treatment because of mass effect of AC itself, abnormal dynamics of the AC fluid, and/or increasing sign of ICP. 13 cases had resection of AC outer membrane with craniotomy, and the remaining two had cystoperitoneal shunt. One of the shunting cases complicated subdural hematoma. Surgical treatment was discussed and radical craniotomy rather than a shunt procedure was preferred. Prognosis of all cases was favorable and uneventful.  相似文献   
53.
The interactions of acidic and basic drugs with 1-acid glycoprotein (1-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to 1-AGP. The CD data suggested the presence of a single binding site on the 1-AGP molecule. The induced ellipticities of the acidic drug–1-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to 1-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with 1-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs.  相似文献   
54.
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 1971–1975 to 62.3%during 1981–1985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 1971–1975and 69.7% during 1981–1985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 37–40 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe.  相似文献   
55.
Recent data have shown the existence of specific changes in mRNAs in thyroid carcinomas. It has not been clarified, however, why these changes clearly distinguish benign tissues from carcinomas, while genomic alternation such as mutations in the RAS or P53 genes do not. Further, the widely believed hypothesis, multi-step carcinogenesis, does not explain some clinical and experimental evidence of thyroid carcinomas. Considering these facts, we propose a new idea for thyroid carcinogenesis called "germ-cell carcinogenesis", in which cancer cells are derived from the remnant of fetal thyroid germ cells(thyroblasts) instead of normal thyroid follicular cells. Utilizing such mRNAs, we have established a new method for preoperative molecular-based diagnosis of thyroid carcinomas, Aspiration Biopsy Nucleic Acid Diagnosis(ABND). ABND allows us to perform preoperative nucleic acid analyses of the tumors by extracting RNAs or DNAs from tumor cells obtained by fine needle aspiration biopsies(FNABs). Pathological diagnosis of thyroid follicular carcinoma is quite difficult, and the establishment of preoperative molecular-based diagnosis of follicular carcinoma has been long expected. We found that quantification of the trefoil factor 3(TFF3)/galectin-3 mRNA ratio in thyroid tumor cells is a useful tool for distinction between follicular adenomas and carcinomas. Because ABND can be performed without any severe invasion to the patients, in the near future, when more reliable systems of quantitative RNA analysis have been developed, ABND will probably become one of the standard tests for preoperative diagnosis of thyroid carcinoma.  相似文献   
56.
In human testis, expression of a novel member of the aldo-keto reductase family was identified. Based on its testis-specific expression, we termed this protein human testis aldo-keto reductase (htAKR). In addition to four major isoforms, the existence of multiple alternatively spliced products of htAKR was detected using RT-PCR followed by nested PCR. htAKR was a homologue of mouse liver keto-reductase, AKR1E1, with close similarity in their genomic organizations. htAKR4, the longest isoform, was expressed as a non-fused native form. It exhibited a limited activity toward 9,10-phenanthrenequinone, while no activity toward the steroids or prostaglandins was demonstrated. Using the laser capture microdissection technique and RT-PCR, expression of htAKR was detected in testicular germ cells as well as in interstitial cells. The levels of htAKR mRNA in the tissues obtained from seminoma were much lower than those in normal testes. A significant decline in the htAKR expression was observed when NEC8, a cell line originated from a human testicular germ cell tumour, was exposed to phorbol 12-myristate 13-acetate or 5alpha-dihydrotestosterone. These results indicate that the expression of htAKR, down-regulated in the testicular tumour, is possibly controlled by mitogenic and hormonal signals.  相似文献   
57.
The hepatic portal vein has been known to make a spontaneous peristaltic movement in some mammals, including the mouse and rat. To investigate the fine structure of the portal vein in relation to its physiological characteristics, we observed the mouse portal vein by using various histological techniques including conventional light microscopy, videomicroscopy, transmission and scanning electron microscopy, and real-time confocal laser scanning microscopy. The mouse hepatic portal vein was provided with a spiral fold which was produced by the inner layer, i.e. the endothelium and smooth muscles of the wall protruding into the lumen. Longitudinal smooth muscle cells spanned the interval of the fold, like a spirally arranged palisade around the vessel wall. The longitudinal muscle fibers ended at the spiral fold, being partly connected with a network of irregularly shaped smooth muscle cells. This network, hitherto unknown, was recognized to be restricted to the fold in distribution and characterized by numerous gap junctions connecting the muscle cells. Real-time confocal laser scanning microscopy using a Ca2+ sensitive fluorescent dye revealed that a transient and periodic increase in Ca2+ concentration occurred in the longitudinal smooth muscle cells and was transmitted spirally from the intestinal to the hepatic side. These findings indicate that, during the peristaltic movement, the contraction of smooth muscle cells is transmitted along the longitudinal smooth muscles of the portal vein wall toward the liver, presumably controlled by the network of the irregularly-shaped smooth muscle cells in the fold of the portal vein. Light microscopic observation in some specimens indicated an occurrence of cardiac muscle cells outside the smooth muscle layer. Restricted to the site of the porta hepatis in distribution, their involvement in the peristaltic contraction of the portal vein seemed unlikely.  相似文献   
58.
Summary In order to explore the relationship between the expression of cancer-associated glycolipids such as sialylated Lex (SLEX) and sialylated Lea (SLEA) and the histological subtypes of lung cancers, 30 cases of small cell carcinoma (SCC) and 47 cases of non-small cell carcinoma (non-SCC) were examined immunohistochemically using monoclonal antibodies reacting with SLEX and SLEA. The forty-seven cases of non-SCC included 20 cases of adenocarcinoma, 20 of squamous cell carcinoma and 7 of large cell carcinoma. Tumour cells of most non-SCCs expressed SLEX and SLEA. In adenocarcinomas, the number of tumour cells having SLEX and SLEA was more than that of squamous cell carcinomas, large cell carcinomas and SCC. In SCC, 14 of the 30 cases were found to be positive for both antigens. Although the cancer cells of 11 cases of 17 intermediate cell type SCC had both antigens, the cells of only 3 of 13 oat cell tumours expressed SLEX and SLEA. The present study shows that SLEX and SLEA are useful markers for lung adenocarcinomas, that most cases of intermediate cell type of SCCs have characteristics similar to non-SCC but that many oat cell tumours lack them.  相似文献   
59.
Prion protein (PrP) is known to accumulate in some non-neuronal tissues under conditions unrelated to prion diseases. The biochemical and biological nature of such accumulated PrP molecules, however, has not been fully evaluated. In this study, we established experimental myopathy in hamsters by long-term administration of chloroquine, and we examined the nature of the PrP molecules that accumulated. PrP accumulation was immunohistochemically demonstrated in autophagic vacuoles in degenerated muscle fibers, and this was accompanied by the accumulation of other molecules related to the neuropathogenesis of prion diseases such as clathrin, cathepsin B, heparan sulfate, and apolipoprotein J. Accumulated PrP molecules were partially insoluble in detergent solution and were slightly less sensitive to proteinase K digestion than normal cellular PrP. Muscle homogenates containing these PrP molecules did not cause disease in inoculated hamsters. The findings indicate that the PrP molecules that accumulated in muscle fibers have distinct biochemical and biological properties. Therefore, experimental chloroquine myopathy is a novel and useful model to investigate the mechanism of deposition of PrP in non-neuronal tissues and might provide new insights in the pathogenesis of prion diseases.  相似文献   
60.
Rodent and human clinical studies have shown that transplantation of bone marrow stem cells to the ischemic myocardium results in improved cardiac function. In this study, cynomolgus monkey acute myocardial infarction was generated by ligating the left anterior descending artery, and autologous CD34(+) cells were transplanted to the peri-ischemic zone. To track the in vivo fate of transplanted cells, CD34(+) cells were genetically marked with green fluorescent protein (GFP) using a lentivirus vector before transplantation (marking efficiency, 41% on average). The group receiving cells (n = 4) demonstrated improved regional blood flow and cardiac function compared with the saline-treated group (n =4) at 2 weeks after transplant. However, very few transplanted cell-derived, GFP-positive cells were found incorporated into the vascular structure, and GFP-positive cardiomyocytes were not detected in the repaired tissue. On the other hand, cultured CD34(+) cells were found to secrete vascular endothelial growth factor (VEGF), and the in vivo regional VEGF levels showed a significant increase after the transplantation. These results suggest that the improvement is not the result of generation of transplanted cell-derived endothelial cells or cardiomyocytes; and raise the possibility that angiogenic cytokines secreted from transplanted cells potentiate angiogenic activity of endogenous cells.  相似文献   
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