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1.
Summary The immunohistochemical localization of large proteoglycan and small proteoglycan was observed, using antibodies 2B1 and 6B6 (Sobueet al., 1988, 1989a), in fetal and adult pancreas and biliary system as well as in tumour tissues, obtained from 11 autopsies and 74 biopsies. The distribution of chondroitin 4- and 6-sulphate side chains, type I and IV collagen and elastin were also studied. In adult pancreas and all the biliary tracts examined, periductal fibrous tissues consisted mainly of dermatan sulphate small proteoglycan with networks of fibrous elements, which were composed of large proteoglycan, elastin, type I collagen and type IV collagen. In the interstitial components of cystadenoma of pancreas and biliary duct carcinoma, similar small proteoglycan-rich components were relatively abundant, although large proteoglycan was present in much larger amounts than that in non-neoplastic adult tissues. In some cholangiomas, the extra-and intracellular hyaline globules formed by the carcinoma cells were found to contain chondroitin sulphate large proteoglycan, laminin and fibronectin.The distribution of proteoglycans was observed to be different in the arterial walls of the interlobular tissues of the adult and the fetal pancreas. The biological significance of large and small proteoglycans in the interstitial connective tissues was discussed.  相似文献   
2.
Adrenocorticotropin-releasing hormone (CRH) is a peptide originally isolated from the hypothalamus. Immunocytochemical and RIA studies have revealed that CRH-like peptide is also localized in human nonhypothalamic tissues and some tumors. To see if CRH is synthesized in these nonhypothalamic tissues and tumors, we examined preproCRH mRNA in these tissues by Northern blot analysis using a cloned human preproCRH gene as a probe. PreproCRH mRNA was detected in human hypothalamus, cerebral cortex, adrenal gland, placenta, pheochromocytoma, and thymic carcinoid. The content of preproCRH mRNA in placenta was apparently greater than that in the whole hypothalamus.  相似文献   
3.
We have investigated cauliflower (Brassica oleracea) topoisomerase II with respect to its interaction with DNA and demonstrate that the enzyme shares the characteristics of topoisomerase II purified from a variety of phylogenetically remote organisms. In the presence of the 2-nitroimidazole Ro 15-0216, cauliflower topoisomerase II-mediated DNA cleavage is extensively stimulated (approximately 20-fold) only at a site recognized as a major cleavage site for the enzyme in the absence of drug. The conservation of the enzyme's DNA specificity in the presence of Ro 15-0216 is in contrast to the effect exerted by traditional topoisomerase II inhibitors, which cause enzyme-mediated cleavage to take place at a multiple number of DNA sites. Ro 15-0216 may therefore prove useful as a tool in the elucidation of the enzyme's DNA interaction sites and its involvement in nucleic acid metabolism in plant cells.  相似文献   
4.
Angiotensin-converting enzyme (ACE) activity was measured in 10 patients with anorexia nervosa, 6 with hyperthyroid Graves' disease, and 7 with primary hypothyroidism. Patients with anorexia nervosa had a low serum ACE activity (9.8 +/- 2.2 IU/l), as compared to findings in normal subjects (13.4 +/- 3.5 IU/l) (P less than 0.05). Patients with hyperthyroid Graves' disease had high serum ACE activity (23.7 +/- 5.8 IU/l), as compared to levels in normal subjects (P less than 0.01), and patients with primary hypothyroidism tended to have low serum ACE activity (10.1 +/- 1.8 IU/l), compared to the normal subjects (P less than 0.1). Following weight gain (before; 71.3 +/- 10.2% of ideal body weight, after; 88.7 +/- 5.6% of ideal body weight), serum ACE activity in patients with anorexia nervosa reverted to within the normal range (13.8 +/- 3.5 IU/l), and serum T3 concentration was restored to the normal range (before; 0.7 +/- 0.2 ng/ml, after; 1.1 +/- 0.3 ng/ml). In these patients, ACE activity correlated with the per cent of ideal body weight (P less than 0.05). These data suggest that, in underweight subjects with anorexia nervosa, decreased serum ACE activities may relate to emaciation.  相似文献   
5.
Human corticotropin-releasing hormone (hCRH) test was performed in 57 normal volunteers and 102 patients with hypothalamic, pituitary and adrenocortical diseases. Intravenous bolus injection of synthetic hCRH, 100 micrograms for adults or 1.5 micrograms/kg for children, increased plasma ACTH and cortisol levels in about 90% of normal subjects. In 47 patients with Cushing's disease, plasma ACTH tended to show an exaggerated response to hCRH and peak ACTH was the most frequent abnormal component among the several reaction parameters. Poor responders among normal subjects and patients with Cushing's disease had significantly higher plasma cortisol levels before CRH administration. Patients with hypothalamic hypopituitarism showed exaggerated response, whereas patients with primary pituitary lesion, isolated ACTH deficiency or adrenal Cushing's syndrome showed no ACTH response. These differences in the response of patients suggest the value of the hCRH test in their differential diagnosis.  相似文献   
6.
To study the gene products of the HLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked to HLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of the HLA-D region on a molecular level.  相似文献   
7.
8.
For all biological particles such as cells or cellular organelles, there are three-dimensional coordinates representing the centroid or center of gravity. These coordinates and other numerical parameters such as volume, fluorescence intensity, surface area, and shape are referred to in this paper as geometric properties, which may provide critical information for the clarification ofin situmechanisms of molecular and cellular functions in living organisms. We have established a method for the elucidation of these properties, designated the three-dimensional labeling program (3DLP). Algorithms of 3DLP are so simple that this method can be carried out through the use of software combinations in image analysis on a personal computer. To evaluate 3DLP, it was applied to a 32-cell-stage sea urchin embryo, double stained with FITC for cellular protein of blastomeres and propidium iodide for nuclear DNA. A stack of optical serial section images was obtained by confocal laser scanning microscopy. The method was found effective for determining geometric properties and should prove applicable to the study of many different kinds of biological particles in three-dimensional space.  相似文献   
9.
The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries. The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45–99-yr-old; 15 of the subjects were males and 8 were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found. When related to age, two groups were established. Group L (45–75 yr old) and group H (>75 yr old), which exhibited aortal Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia, Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P) levels (r=0.801,p<0.01) and between Al and calcium (Ca) (r=0.661,p<0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery. In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation.  相似文献   
10.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.  相似文献   
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