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31.
Changes in the activity of serum gamma-glutamyl transpeptidase (gamma-GTP) and the percentage of the gamma-GTP fraction in healthy young men given a high carbohydrate diet (480-636 g/day, 80% of the total energy) for 21 days were examined. Serum total gamma-GTP activity showed no significant change in four healthy young volunteers who received high carbohydrate diet for 21 days. However, the percentage of the gamma-GTP (1) fraction increased significantly (P less than 0.01) from the basal level of 55.6 +/- 4.0% to 67.6 +/- 0.9% on day 10, and then decreased to 58.4 +/- 1.4% on day 21. When the experimental diet was replaced by usual diet, the percentage of the gamma-GTP (1) fraction returned to the same level as before the experiment. It is concluded from the results that the nutrient intake affects the percentage of gamma-GTP (1), but not the total serum gamma-GTP activity.  相似文献   
32.
Five forms of serine proteinase (EC 3.4.21.14) have been purified fromAspergillus sojae. This paper reports heterogeneity of electrophoretic mobilities, isoelectric points, and kinetic parameters of multiple forms of serine proteinase fromAspergillus sojae, including agerelated changes in thek cat /K m of electrophoretic species.  相似文献   
33.
The molecular properties, such as molecular weight, N-and C-terminal amino acids, amino acid composition, and circular dichroism, of 1,2--mannosidase isolated from the culture filtrate ofAspergillus saitoi were determined.The enzyme had aK m of 0.67 mM andk cat of 1.27/s with mannobiose at pH 50.0 and 30°C. The anomeric configuration of the reaction products of the enzyme was examined by studying the -anomer. A single Manl2Man linkage in intact Taka-amylase A fromAspergillus oryzae was hydrolyzed, producing free mannose.  相似文献   
34.
Summary Touch smears of the cerebellum and cerebrum of ageing rats were fixed with methanol, hydrolyzed with 2N HCl at various temperatures and for various periods, and stained with pararosaniline-Schiff reagent. The hydrolysis curves were determined by fluorescence cytophotometry and were computer fitted to the Bateman function to determine the kinetic parameters, the initial yield of apurinic acid or single-stranded DNA (y 0), and the rate constants for depurination or denaturation (k 1) and depolymerization (k 2). The values for k 1 (1/k 1 is correlated with the degree of chromatin condensation) and k 2 (which reflects the degree of DNA instability) steadily increased with age. The values for y 0, which may indicate the degree of DNA denaturation or damage present before acid hydrolysis, also increased with age in both the cerebellum and cerebrum; however, this value was lower in the cerebellum untill 15 weeks, with the situation being reversed after 35 weeks, the cross-over time being at about 25 weeks. The values of lnk 1 and lnk 2 were plotted as the function of the reciprocal of the absolute temperature (T) (Arrhenius plot) for both the cerebellum and cerebrum of 15- and 74-week-old rats, and the activation energies (E) for depurination and depolymerization were calculated from the slopes. In particular, the values of E for k 2 decreased much more quickly with age and were smaller in cerebellum. In conclusion, the degree of DNA damage and DNA instability steadily increases in both the cerebellum and cerebrum of ageing rats, and this process is much faster in the cerebellum.In honour of Prof. P. van Duijn  相似文献   
35.
Nasal mucociliary clearance was measured in both healthy subjects and patients with chronic sinusitis using saccharin granule technique. Nasal mucociliary transit time (ST) was significantly slower in the patients with chronic sinusitis compared with that in controls (p less than 0.005). Nasal mucus collected from each nasal cavity was used for in vitro bullfrog palate clearance studies and compared to the in vivo nasal ST. Mucociliary clearance rate (MTR) on frog palate was 12.5 +/- 2.5 mm/min in the mucus from control subjects, 6.1 +/- 1.5 mm/min in the mucus from the patients. The difference was statistically significant (p less than 0.005). The MTR on frog palate in the patients whose nasal ST was within normal range was significantly slower than that in controls (p less than 0.005), but not significantly different from that in the patients whose nasal ST was over the normal range. These results suggest that the nasal mucous properties which decreased the mucociliary clearance on frog palate did not contribute to the mucociliary clearance of the patients who had a normal one. No significant correlation existed between MTR on frog palate and nasal ST in both control and chronic sinusitis. In chronic sinusitis patients, decelerated nasal ST was recovered significantly by normal saline nebulization compared with the value before the nebulization (p less than 0.01). None of the significant change of ST was observed in control before and after the nebulization.  相似文献   
36.
Summary Spermatozoa from fertile and infertile human ejaculates were observed under the scanning electron microscope. A parallel study of sections was performed by transmission electron microscope.The normal head shows under the scanning electron microscope vesicular elevations in the region of the acrosome and a smooth and rigid appearance corresponding to the postnuclear cap whose occurrence is confirmed under the transmission electron microscope. Immediately anterior to this cap a shallow furrow transverses the head. Duplicated, unusually large or small and deformed heads are found under the scanning electron microscope. Most of these abnormal heads show no surface structure suggesting an acrosome.The neck and middle piece are occasionally, though frequently in abnormal spermatozoa, covered by a cytoplasmic droplet. Otherwise, the mitochondrial sheath is recognized under the scanning electron microscope as a beaded thickening in the middle piece. The lack of mitochondria is manifested by a smooth middle piece thinner than the principal portion. Transmission electron microscopy of sections reveals various types of anomalies in the number of cores, core filaments and mitochondria embedded in the cytoplasmic droplets.Abnormalities in the principal portion of the tail such as duplication, unusual thickness and length are shown under the scanning electron microscope.The investigation indicates that scanning electron microscopy is suited for the clinical as well as cytological examination of human ejaculate spermatozoa.  相似文献   
37.
Summary The fine structure of the mesonephric kidney of the lamprey, Entosphenus japonicus Martens, has been investigated with the electron microscope and discussed from the viewpoint of comparative morphology of the mesonephros.The structure of the capillary wall of the glomerulus essentially coincides with that of higher vertebrates, though its basement membrane is remarkably thick (300–400 m) because of a dense accumulation of fibrillar material between the endothelium and the basal lamina of epithelial cell. No obvious fenestration of the endothelial cell has been observed in the glomerulus or capillaries in any part of this organ.The kidney tubule is divided into three segments: 1. neck segment composed of ciliated cells with numerous mitochondria and glycogen particles, 2. proximal tubule composed of brush bordered cells provided with extensive pinocytotic vesicles and lysosomal granules in the apical cytoplasm and with lamellar membranes in the basal, and 3. distal tubule characterized by cells which, with their abundant mitochondria and branched tubular endoplasmic reticulum (about 500 Å diameter) with a central core, closely resemble the chloride cells in the gill filament of some teleosts. The possibility that the lamellar membranes in the proximal tubule cells correspond to basal infoldings is discussed.The extensive development of the tubular reticulum and of the mitochondria in the distal tubule cells is believed to reflect the active absorption of urine chloride in the urinary tubule of lamprey mesonephric kidney evidenced by physiologists. The proximal tubule is suggested to take a part also in the urinary transport of water and ions, as the lamellar membranes found in the cells of this portion likely correspond to the basal infoldings in more advanced forms of the kidney.The epithelial cells of the ureteric duct are characterized by granules suggesting a mucous secretion. No fine structure implying an absorptive activity in this duct has been observed.  相似文献   
38.
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL interleukin - IFN interferon - TNF tumor necrosis factor  相似文献   
39.
Lectin histochemistry in rat thyroid tumours   总被引:1,自引:0,他引:1  
The thyroid tumours and background goiterous and adenomatous lesions induced in rats with diisopropanolnitrosamine (DIPN) plus methylthiouracil (MTU), and regenerative thyroid tissues after wounding were studied by lectin histochemistry. Ten weeks after cessation of the carcinogen treatments, carcinomas invading the surrounding tissues and blood vessels (13/20) and papillary micronodules (11/20) were formed in the thyroid tissues. In general, the carcinoma lesion was solitary, and the papillary micronodules were multiple in a single thyroid gland. Among the lectins tested, Maclura pomifera (MPA) and Solanum tuberosum (STA) showed specific binding with both carcinoma and papillary micronodule lesions, but not with the background goiterous and adenomatous lesions and regenerative thyroid tissues. The former both lesions showed higher labelling indices with BUdR or 3H-thymidine and poorer thyroglobulin accumulation than the latters, thereby indicating their enhanced proliferative capability and depressed potency of cyto-differentiation. The common cytological and histochemical properties of carcinoma lesions and papillary micronodules allow us to regard the latter as pre-invading carcinoma lesions. The lectins MPA and STA may be, therefore, used as the specific markers of malignancy in rat thyroid carcinogenesis.  相似文献   
40.
Effect of rice fiber on human fecal microflora   总被引:1,自引:0,他引:1  
The effects of brown rice, containing fourfold as much dietary fiber as polished rice, on the human fecal microflora were determined. Significantly increased numbers of Bifidobacterium adolescentis and Enterococcus faecalis were observed during the brown rice intake, whereas the total counts and the numbers of bacteroides, Eubacterium aerofaciens, and Escherichia coli during the intake were lower than those before and after the intake. Lower numbers of clostridia and low incidences of Clostridium paraputrificum and C. perfringens were observed during the brown rice intake.  相似文献   
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