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11.
A comparative study has been carried out to investigate the performance of the hot-wire spirometer and the Rollingseal spirometer; the reproducibility of the data generated by an individual examiner; and the validity of data obtained by an "inexperienced examiner" using the hot-wire spirometer. The following results were obtained: 1. The experimental data given by the hot-wire spirometer were about 5-6% higher for FVC and FEV1, and about 10-12% higher for PFR, V50, and V25, respectively, when compared to the data generated by the Rollingseal spirometer. 2. The reproducibility of the data produced by the hot-wire spirometer operated by an "experienced examiner" was good, as the percent difference was about +/- 3%. 3. Reliable data were obtained with the spirometer even by an "inexperienced examiner" if he/she has gone through an on-site training concerning instrumentation and measurement methods for spirography.  相似文献   
12.
Two forms of superoxide dismutase, CuZn-SOD and MnSOD, have been investigated in the kidneys of streptozotocin-induced diabetic rats using both radio-immunoassay and immunoenzyme staining. The rats were killed 2, 8 and 12 weeks after the induction of diabetes mellitus and the kidneys excised. Two weeks after the induction of diabetes, the kidneys were hypertrophied because of the proliferation of renal tubular epithelium. However, the total CuZnSOD content of the kidneys did not increase and, because of the epithelial proliferation, the CuZnSOD concentration in each proximal tubular cell was decreased. Armanni-Ebstein lesions were found in the distal tubules 8 and 12 weeks after the induction of diabetes. The cells in these lesions were intensely stained for CuZnSOD, suggesting an adaptive response to the enhanced oxidative stress. The MnSOD staining in the thick ascending limbs of Henle's loops was enhanced in the diabetic kidneys, while that in the cortical tubules was unaltered. MnSOD was assumed to increase in response to hypermetabolism associated with the proliferation of renal tubules. This was most marked in the cells which were rich in mitochondria, again suggesting an adaptive response to enhanced oxidative stress induced by diabetes mellitus. The glomeruli of both the diabetic and control groups were not stained for SODs, and no significant microscopic change was found even 12 weeks after the induction of diabetes mellitus.  相似文献   
13.
Embryos at the morula, blastocyst and hatched blastocyst stage were obtained from superovulated and naturally ovulated Japanese native goats. They were bisected into halves with a glass needle, and transferred immediately or after culture (for morula) to recipients. None of five does which received bisected morula became pregnant. Three of nine goats became pregnant after transfer of bisected hatched blastocysts, six of eleven recipients became pregnant. Four of them produced monozygotic twins and the remaining two produced singles. The present study demonstrated that the hatched blastocyst is suitable for bisection in the goat.  相似文献   
14.
The effect of an intramuscular injection of a new analog of gonadotropin-releasing hormone (GnRH), fertirelin, on the first-service pregnancy rate in cows was investigated by a double blind experiment. A total of 1,194 cows was injected intramuscularly either with 100 mug of GnRH or placebo (physiological saline solution) at the time of first insemination postpartum. Pregnancy rate (number of cows calved/ number of cows serviced) was 57.2 % in 605 cows treated with GnRH, while the performance was 49.7 % in 589 cows of the placebo group. The difference of pregnancy rates in both groups was significant (P<0.05). GnRH injected at insemination was effective, especially in cows at the first and third lactations, cows at 101 days postpartum or later, cows with daily milk yield of 26-30 kg, and also in cows from the area where a regional average fertility was relatively low.  相似文献   
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Nuclear transplantation of male primordial germ cells in the mouse   总被引:2,自引:0,他引:2  
We examined the developmental ability of enucleated eggs receiving embryonic nuclei and male primordial germ cells (PGCs) in the mouse. Reconstituted eggs developed into the blastocyst stage only when an earlier 2-cell nucleus was transplanted (36%) but very rarely if the donor nucleus was derived from a later 2-cell, 8-cell, or inner cell mass of a blastocyst (0-3%). 54-100%, 11-67%, 6-43% and 6-20% of enucleated eggs receiving male PGCs developed to 2-cell, 4-cell, 8-cell and blastocyst stage, respectively, in culture. The overall success rate when taking into account the total number of attempts at introducing germ cells was actually 0-6%. Live fetuses were not obtained after transfer of reconstituted eggs to recipients, although implantation sites were observed. The developmental ability of reconstituted eggs in relation to embryonic genome activation and genomic imprinting is discussed.  相似文献   
18.
Biological activities of two groups of synthesized lipid A analogs, the counterpart of biosynthetic precursor, Lehmann's Ia type, 406, and E. coli lipid A type, 506, as well as their non-phosphorylated, and mono-phosphorylated analogs were investigated. The activities employed included four bone marrow cell reactions in mice, mice skin reaction, leukocytes migration in rabbits' cornea, and hemagglutination. Compound 406 and 506 elicited bone marrow reactions in mice and hemagglutination of mouse RBC, although 406 failed to elicit hemorrhage and necrosis also in mice skin. Compound 406 did not elicit corneal reaction in rabbits. The results suggest that for elicitation of this reaction and mice skin reaction, acyloxyacyl structure is required. Cytotoxicity and thromboplastin production of four bone marrow reactions had been reported by us to be endotoxic reactions, since these had not been elicited by peptidoglycan of Lactobacillus and Staphylococcus (1981) and 300 series synthesized analogs (1984) which did not have endotoxic structures. From these results, it seems that these two marrow reactions and hemagglutination require, as does the limulus test, the lipid A part structure as is present in 406.  相似文献   
19.
We report a missense mutation in an adult Japanese patient with acid alpha-glucosidase (GAA) deficiency. A TC to GT transition at nucleotides 1585–1586, was identified. This transition resulted in an amino acid substitution of Ser-529 to Val (S529V) in exon 11. We also have demonstrated that the S529V mutation abolishes the catalytic activity of the enzyme. Our data suggest that this mutation is the cause of the clinical manifestation known as adult-onset GAA deficiency. The missense mutation described here is a new mutation, and the first identified in Japanese patients with GAA deficiency. Received: 23 May 1995  相似文献   
20.
Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol–1 of EPO, there was no further increase in their activity over 12.4 mol mol–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO erythropoietin - rHuEPO recombinant human erythropoietin - hCG human chorionic gonadotropin - BHK baby hamster kidney - CHO Chinese hamster ovary - NeuAc N-acetyl neuraminic acid - Gal galactose - HRCs hemolyser-resistant cells - WST-1 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na - IEF isoelectric focusing - pI isoelectric point  相似文献   
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