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91.
Cytogenetic abnormalities in human malignancies frequently involve chromosome 7. The existence of several tumor suppressor genes on the long arm of chromosome 7 has been suggested in both epithelial and hematologic malignancies. From the Danish Cytogenetic Register, we identified 183 persons with constitutional abnormalities involving chromosome 7, including 16 patients with Williams syndrome. By linkage to the Danish Cancer Registry, we found five persons with cancer, including one thyroid carcinoma, three carcinomas of the digestive tract, and one malignant melanoma. There were no cases of leukemia. The overall risk of developing cancer was not increased.  相似文献   
92.
EJ Lee  YC Hung  CH Chang  MC Pai  HH Chen 《Canadian Metallurgical Quarterly》1998,140(6):599-604; discussion 604-5
The purpose of this study was to evaluate pre- and post-shunting haemodynamic changes and their correlation with the clinical results in normal pressure hydrocephalus (NPH). Accordingly, eleven demented patients with clinical signs suggestive of NPH received examinations of cerebral blood flow velocity (BFV) and vasomotor reactivity (VMR) by transcranial Doppler sonography with carbogen testing before and after shunt treatment. Computerized tomography (CT), clinical assessment and neuropsychological grading were performed prior to and at 3 months following surgery. A control group consisting of 10 patients was included to establish baseline data. The pre-operative CBF studies in the anterior cerebral artery (ACA) and the middle cerebral artery (MCA) revealed the NPH patients did not have significant decreases of BFVs, but had significant decreases of carbogen VMR (P < 0.05). After shunting, there were no significant changes of the BFVs as compared with the pre-shunting data. The post-shunting VMR of the ACA was significantly higher than the pre-shunting one (p < 0.05), but there was no variation in that of the MCA. Both the values of post-shunting VMR in ACA and the post-shunting increase in VMR in MCA of the 7 shunt-responsive patients who improved mentally and in other symptoms were significantly higher than those of patients without improvement (p < 0.05). In addition, the five patients with gait improvement showed significantly higher values of post-shunting VMR of ACA and the post-shunting increase of VMR for both ACA and MCA when compared with those patients without gait improvement (p < 0.05, respectively). Our study supports the view that patients with NPH had various degrees of impaired VMR in both the ACA and the MCA, but showed insignificant reduction in BFVs, indicating a compensatory mechanism of CBF over time to accommodate the subnormal state of cerebral perfusion pressure. Shunt placement would improve the VMR in responsive patients. Postoperatively, an increase of VMR tends to accompany improvement of the functional state: that in the MCA alone is associated with symptomatic improvement in mental function and that increase in VMR in both the ACA and the MCA with improvement in gait, respectively.  相似文献   
93.
We have employed polyclonal antibodies to a peptide sequence of bovine steroidogenic acute regulatory (StAR) protein and human placental 3beta-hydroxysteroid dehydrogenase (3beta-HSD) to determine the localisation and distribution of these proteins in rat and bovine adrenal glands. Immunohistochemical staining demonstrated the presence of StAR protein in the zona glomerulosa (ZG), zona fasciculata (ZF), zona reticularis (ZR) and in the medulla of both species. For 3beta-HSD, immunostaining was observed in the ZG, ZF and ZR of the rat adrenal and was absent in the medulla. Immunoblotting experiments showed intense bands for StAR protein (30 kDa, 37 kDa) in the mitochondria of bovine ZG, ZF and medulla and a less intense band (30 kDa) in the microsomes. In rat ZG and ZF/R mitochondria only the 30 kDa protein was present. For 3beta-HSD, an intense band (42 kDa) was found in microsomes and mitochondria of rat and bovine ZG and ZFR. A very faint signal for 3beta-HSD was seen in adrenal medulla. In conclusion, StAR (or a closely related) protein is present throughout the adrenal gland in rat and bovine species in contrast to 3beta-HSD which is confined to the steroidogenic zones. The possible function of StAR protein in the adrenal medulla merits investigation.  相似文献   
94.
BACKGROUND: Experience suggests that tumor growth is dependent on angiogenesis. The intensity of angiogenesis in human cancer is reported to be predictive of the probability of metastasis in many types of cancer. The aims of this study were 1) to determine the relationship of microvessel density (MVD) in renal cell carcinoma to pathologic stage, and 2) to evaluate the role of MVD in metastasis. METHODS: Paraffin-embedded tumor specimens were reviewed from 34 unselected patients with RCC who had undergone surgery from 1986 to 1990 at Taichung Veterans General Hospital. The pathology findings and clinical records were reviewed to note relationships between pathologic stage and whether or not metastasis had occurred. Specimens were studied from 16 cases (eight Stage I cancers, five Stage II and three Stage III) without metastasis and from 18 cases (two Stage I, six Stage II, six Stage III and four Stage IV) in which metastasis later developed. Microvessels were highlighted by immunostaining endothelial cells for factor VIII-related antigen. Microvessels were counted in a x-400 field (0.1885 mm2/field) in the most active areas of neovascularization. RESULTS: The 16 patients without metastasis have survived for between 65 and 136 months (mean, 94.5 months), up to the present time. Of the 18 patients with metastasis, 15 died and three survived, with mean survivals of 42.8 months (range, 12-99 months). Mean overall MVD was 99.6 vessels; mean MVD was 98.5, 96.2, 109.3 and 90.0 in Stages I, II, III and IV tumors, respectively. Mean MVD was 99.3 in patients without metastasis and 99.9 in patients with metastasis. CONCLUSIONS: MVD does not correlate with pathologic stage and is of no prognostic significance in renal cell carcinoma.  相似文献   
95.
96.
We here demonstrated the prophylactic effect of an extract (KM-110) from Viscum album coloratum, a Korean mistletoe, on tumor metastasis produced by highly metastatic tumor cells, colon 26-M3.1 carcinoma, B16-BL6 melanoma and L5178Y-ML25 lymphoma cells, using experimental models in mice. Intravenous (i.v.) administration of KM-110 (100 microg/mouse) 2 days before tumor inoculation significantly inhibited lung metastasis of B16-BL6 and colon 26-M3.1 cells, and liver and spleen metastasis of L5178Y-ML25 cells. The prophylactic effect of KM-110 on tumor metastasis was evident with various administration routes, i.e. subcutaneous, oral, intranasal as well as i.v., and was dependent upon the dose of KM-110 administered. Furthermore, mice given KM-110 (100 microg) 2 days before tumor inoculation showed significantly prolonged survival rates compared with the untreated mice. In a time course analysis of NK activity, i.v. administration of KM-110 (100 microg) significantly augmented NK cytotoxicity to Yac-a tumor cells from 1 to 3 days after KM-110 treatment. Furthermore, depletion NK cells by injection of rabbit anti-asialo GM1 serum completely abolished the inhibitory effect of KM-110 on lung metastasis of colon 26-M3.1 cells. These results suggest that KM-110 possesses immunopotentiating activity which enhances the host defense system against tumors, and that its prophylactic effect on tumor metastasis is mediated by NK cell activation.  相似文献   
97.
Almost all variables in biology are nonstationarily stochastic. For these variables, the conventional tools leave us a feeling that some valuable information is thrown away and that a complex phenomenon is presented imprecisely. Here, we apply recent advances initially made in the study of ocean waves to study the blood pressure waves in the lung. We note first that, in a long wave train, the handling of the local mean is of predominant importance. It is shown that a signal can be described by a sum of a series of intrinsic mode functions, each of which has zero local mean at all times. The process of deriving this series is called the "empirical mode decomposition method." Conventionally, Fourier analysis represents the data by sine and cosine functions, but no instantaneous frequency can be defined. In the new way, the data are represented by intrinsic mode functions, to which Hilbert transform can be used. Titchmarsh [Titchmarsh, E. C. (1948) Introduction to the Theory of Fourier Integrals (Oxford Univ. Press, Oxford)] has shown that a signal and i times its Hilbert transform together define a complex variable. From that complex variable, the instantaneous frequency, instantaneous amplitude, Hilbert spectrum, and marginal Hilbert spectrum have been defined. In addition, the Gumbel extreme-value statistics are applied. We present all of these features of the blood pressure records here for the reader to see how they look. In the future, we have to learn how these features change with disease or interventions.  相似文献   
98.
Regulation of the excurrent ducts of the testis is not well understood, particularly in avian species. To investigate the role of steroid hormones in the male reproductive tract, we developed a primary cell culture of epithelia isolated from rooster ductuli efferentes (efferent ductules). Efferent ductules of the avian testis comprise 77% of the epididymal region and form a mass of tubules containing a heavily folded epithelium enmeshed in connective tissue. The epididymal region was separated by microdissection and small epithelial plaques isolated by serial digestion with collagenase, elastase and repeated pipetting. Isolated cell plaques were cultured in a bicameral chamber on Millicell-CM inserts coated with two layers of basement membrane matrix, consisting primarily of laminin and Types I and IV collagen. Active ciliary beat was observed before plating and this activity was maintained for 14 days in culture. Cell plaques attached within 24 h and outgrowths formed a confluent monolayer by 5-6 days. The epithelial nature of cultured cells was demonstrated by immunocytochemical staining for cytokeratin. Light and electron microscopy confirmed that morphology and polarity of the original epithelial cells were maintained in culture. Cultured efferent ductal epithelium was cuboidal in shape and maintained many of the cytoplasmic organelles typical of these cells in vivo. The uptake of cationic ferritin indicated the endocytotic activity of these cultured cells was maintained. Estrogen receptor mRNA expression was maintained in cultured cells. These data demonstrate avian efferent ductal epithelium can be isolated and grown in defined culture medium for the purpose of determining the role of hormones and other factors in regulating the function of the epididymal region in the bird.  相似文献   
99.
beta-L-1,3-Dioxolane-cytidine (L-(-)-OddC) is a novel L-nucleoside, and its antitumor activity is under investigation in clinical trials. To evaluate the potential of L-(-)-OddC for treating hyperproliferative diseases of the skin, we examined its activity in human keratinocytes in vitro. The dose of L-(-)-OddC that inhibited the rate of proliferation of keratinocytes by 50% was 50 nM. L-(-)-OddC was about as cytotoxic as 9-beta-D-arabinofuranosylcytosine but was about 1,000 time more potent than 3'-azidothymidine. L-(-)-OddC caused irreversible growth arrest and induced differentiation of keratinocytes. L-(-)-OddC altered morphology, increased the cell size of keratinocytes and increased the expression of involucrin. These data suggest that L-(-)-OddC may have potential as a therapeutic agent against hyperproliferative skin diseases.  相似文献   
100.
Effects of a single dose of betaine on the chloroform-induced hepatotoxicity were examined in adult male ICR mice. Administration of betaine (1000 mg/kg, ip) 1 to 7 hr prior to a chloroform challenge (0.25 ml/kg, ip) resulted in remarkable enhancement of hepatotoxicity as indicated by increases in serum sorbitol dehydrogenase (SDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. The potentiation of hepatotoxicity was most significant when mice were treated with betaine 4 hr earlier than chloroform. However, a 24 hr prior administration of betaine protected the animals from induction of the chloroform hepatotoxicity. Thus, its effect appeared to be highly dependent on the time lapse from the betaine pretreatment to the challenge of mice with chloroform. Betaine treated either 4 or 24 hr prior to sacrifice did not alter the hepatic contents of cytochrome P-450, cytochrome b5, or NADPH cytochrome P-450 reductase activity. Accordingly the hepatic microsomal p-nitroanisole O-demethylase, aminopyrine N-demethylase, or p-nitrophenol hydroxylase activities were not influenced by the betaine pretreatment. Betaine was shown not to affect any of the enzyme activities associated with glutathione (GSH) conjugation reaction, such as glutathione S-transferases (GSTs), glutathione disulfide (GSSG) reductase and GSH peroxidase irrespective of the time of its administration. When betaine was administered to mice 2-6 hr prior to sacrifice, hepatic GSH level, but not plasma GSH, was decreased significantly. Enhancement of the chloroform hepatotoxicity by betaine correlated well with the reduction in hepatic GSH levels. Both hepatic and plasma GSH levels were elevated in mice 24 hr following the betaine treatment. The results suggest that betaine affects induction of the chloroform hepatotoxicity by modulating the availability of hepatic GSH, which appears to be associated with its role in the transsulfuration pathway in the liver.  相似文献   
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