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41.
A case of giant cell carcinom of the pancreas is reported herein. The patient is a 67-year-old Japanese woman complaining of ascites, general fatigue, loss of weight, abdominal distention, nausea, and vomiting. Cytological diagnosis of ascites revealed adenocarcinoma. At autopsy, a whitish tumor measuring around 5 cm in diameter was found at the head of the pancreas. Metastasis was seen only in the liver. Histological examination displayed bizarre multinucleated giant cells occasionally phagocytosing the tumor cells and neutrophils.  相似文献   
42.
Protodioscin (PD) was purified from fenugreek (Trigonella foenumgraecum L.) and identified by Mass, and 1H- and 13C-NMR. The effects of PD on cell viability in human leukemia HL-60 and human stomach cancer KATO III cells were investigated. PD displayed strong growth inhibitory effect against HL-60 cells, but weak growth inhibitory effect on KATO III cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with PD, but not in KATO III cells treated with PD. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 75.2, 96.3, and 100% after a 3-day treatment with 2.5, 5, and 10 microM PD, respectively. The fragmentation by PD of DNA to oligonucleosomal-sized fragments, that is a characteristic of apoptosis, was observed to be both concentration- and time-dependent in the HL-60 cells. These findings suggest that growth inhibition by PD of HL-60 cells results from the induction of apoptosis by this compound in HL-60 cells.  相似文献   
43.
The exposure of human lymphoid leukemia Molt 4B cells to sesaminol, a component of sesame oil led to both growth inhibition and the induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with sesaminol. The fragmentation of DNA by sesaminol to oligonucleosomal-sized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. These findings suggest that growth inhibition of Molt 4B cells by sesaminol results from the induction of apoptosis in the cells.  相似文献   
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45.
The discovery of sickle cell hemoglobin in 1949 lead to the concept of "molecular disease". Since then, the total number of abnormal hemoglobins has been increasing, reaching 750 in April, 1998. Of these, 91% are variants with single amino acid substitutions. A "scratch" made in the protein moiety can cause alterations in physicochemical properties such as oxygen affinity, stability and autooxidation of 50% of all variants, further causing hematological or clinical disorders with significant frequencies. Generally, these alterations in properties and consequent hematological or clinical disorders are closely related to the mode and intramolecular location of the mutation. Conventional laboratory methods for mass screening of abnormal hemoglobins such as electrophoresis, isoelectric focusing and ion-exchange HPLC may overlook clinically important variants which possess amino acid substitutions without change in the charge. Oxygen affinity measurement may be a useful method to detect silent variants. Modern apparatuses can quickly and conveniently construct a continuous oxygen dissociation curve from one drop of whole blood. The dissociation curve becomes biphasic when the red cell contains abnormal hemoglobin with abnormal oxygen affinity. The continuous curve recording is advantageous because the proportion of the abnormal hemoglobin component can be estimated and the abnormal chain, either alpha or beta, can be predicted based on the inflection point of the biphasic curve.  相似文献   
46.
Some researchers have already described the fowl proventriculus. However, we believed there was a need for detailed carbohydrate histochemical investigations on the same glands. Moreover, some researchers had erred about the lamina muscularis mucosae. The results of these investigations are as follows. 1. The proventricular glands consist of both superficial and profound gastric glands. 2. The superficial glands are distributed in the lamina propria mucosae while the profound glands exist in the tela submucosa. 3. The superficial glands are simple, branched tubular glands. The columnar glandular cells are arranged in a simple layer and react strongly to PAS, AB (pH 2.5 and 0.5). These appear to be dark purple when they are stained with PAS-AB (pH 2.5). Some other methods have also been tried. 4. Judging from the data 3), the superficial gastric glands contain neutral, weak and strong acids, sulfuric and acid mucopolysaccharides, sialomucin, and II and III neutral mucus type. 5. Glandular cells in the body and basal portions of the superficial gastric glands contain a large number of fine pepsinogen granules. 6. Judging from the data of 3)-5), we believe that the superficial gastric glands are undifferentiated gastric glands and that they are same kinds of glands that are found in mammals. 7. A large number of profound gastric glands fill the tela submucosa. They are compound tubular glands, and are composed of many glandular alveoli. Their columnar glandular cells are arranged in a simple layer. 8. These glandular cells react moderately to PAS, negatively to AB (pH 2.5 and 0.5) and PAS-AB (pH 2.5). Moreover, we observed some other reactions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
47.
Direct tubular effects of arginine vasopressin (AVP) on water and NaCl transport across the medullary thick ascending limb of Henle (MAL) were examined by the in vitro perfusion of isolated nephron fragments of mice, rats, and rabbits. Osmotic water permeability of the MAL of mice and rats was low and remained unchanged with 2 mU/ml AVP added to the bath. A dose-dependent increase in transepithelial electrical potential difference (PD) with AVP was observed in the mouse MAL when the ambient medium was isotonic. A similar result was also obtained when 2×10–4 mol/l dibutyryl adenosine 3,5-cyclic-monophosphate was added to the bath. In this preparation, AVP also caused an increase in the unidirectional Cl efflux from 323±45 to 398±61 pmoles·mm–1 ·min–1 (n=6,P<0.05). In contrast, under similar condition, we could not demonstrate any effect of AVP on PD, Cl efflux, or net Na flux in the rat MAL and on PD and Cl efflux in the rabbit MAL. Both PD and Cl efflux in the rat MAL were unaffected by AVP when the perfusate was made hypotonic. However, when the ambient medium was made hypertonic by adding NaCl and urea, a significant increase in PD was observed. In addition, we confirmed that AVP stimulated adenylate cyclase activity in the MAL as well as in the collecting tubule of mice and rats. We conclude that AVP stimulates Cl transport across the MAL of mice and rats by activating adenylate cyclase-cyclic AMP system. However, this effect of AVP may quantitatively vary among species.  相似文献   
48.
49.
A new monoclonal antibody (MoAb) HA58 (IgG1) was prepared, which recognizes the binding site on the intercellular adhesion molecule-1 (ICAM-1) antigen to the lymphocyte function-associated antigen-1 (LFA-1). The double-determinant immunoassay (DDIA) was established with use of MoAb HA58 and another anti-ICAM-1, MoAb CL207, to detect the soluble, shedding ICAM-1 antigen. Human recombinant interferon-gamma (IFN-gamma) induced not only the expression of cell surface ICAM-1, but also the shedding ICAM-1 antigen in an IFN-gamma concentration-dependent and incubation-time-dependent manner. DDIA was applied to detect the shedding ICAM-1 antigen in the sera of patients with malignant or benign diseases. The incidence of positivity for ICAM-1 antigen in malignant diseases was higher than that in benign diseases or in healthy controls. Furthermore, the sera of cancer patients with liver metastasis showed higher levels of the shedding ICAM-1 antigen. These findings suggest that serum ICAM-1 antigen may be a useful marker to monitor tumor burden in cancer patients.  相似文献   
50.
We encountered a patient who developed an overlap syndrome of progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE), polymyositis (PM) and Sj?gren's syndrome (SjS) while we were treating her for mixed connective tissue disease (MCTD). This 42-year-old woman had been photosensitive since 18 years of age. In 1986, Raynaud's phenomenon, swollen hands and arthralgia appeared; therefore, we started to treat this patient based on a diagnosis of MCTD. At that time, her anti-RNP antibody titer was 82,920, but she was negative to anti-Sm antibody. In 1988, she was admitted to our hospital with chief complaints of aggravation of polyarthralgia and myalgia. On physical examination, she showed difficulty in opening her mouth, systemic dermal sclerosis, a decrease in muscular strength and rales. In laboratory tests, her myogenic enzyme level was increased, and she was found to be positive to LE cells, antinuclear antibody, anti-DNA antibody, anti-ENA antibody and anti-SSA antibody. Furthermore, histological features clearly corresponding to those of PSS were found by skin biopsy, myogenic changes by electromyography, evidence of chronic inflammation of the salivary glands by lip biopsy, and proliferative changes in the mesangium were detected by renal biopsy. The concept of MCTD, especially the differences from overlap syndrome, is vague. Therefore we need further study about many cases. Since there have been no reports on cases having sufficient evidence of the development of the overlap syndrome of PSS, SLE, PM and SjS during a course of MCTD, our patient would provide very useful data contributing to the study of MCTD.  相似文献   
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