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11.
We have recently reported the secretory profile of relaxin throughout gestation in the cat. Because the appearance of relaxin begins at about Day 20 (Day O = ovulation) and because implantation begins shortly before this at Days 13-14, we hypothesized that relaxin was of feto-placental origin. To test this hypothesis, we used 4 experimental groups: 1) Control (laparotomy-only at Day 23 or 42, n = 4); 2) Early Ovariectomy (Ovx, bilateral ovariectomy between Days 23 and 26, n = 4); 3) Late Ovx (bilateral ovariectomy between Days 40 and 44, n = 4); 4) Tissue Removal (removal of feto-placental units, uterus, and one ovary on Days 16, 21, 28 and 35, n = 1 per day). Pregnancies were maintained in both Ovx groups by progesterone administration. Relaxin secretory patterns in Ovx groups were similar to the Control data. Relaxin was detectable in plasma beginning at about Day 20, with maximum concentrations reached by Day 30. Relaxin concentrations were highest (immunoactivity per mg tissue) in homogenates of placental tissues as compared to luteal, fetal, or uterine tissues. Altogether, these data indicate that the feto-placental unit is the source of relaxin in the cat. 相似文献
12.
Basic properties of the binding of [131I]-labeled rat FSH ([131I]rFSH) to the testicular homogenates of fetal rats were analyzed by micro-radioreceptor assay. Specific binding of FSH was detectable in the testicular preparations from 15.5-day fetuses, but it was very low. After 17.5 days of gestation, specific FSH binding was apparent in the testis and was effectively displaced by rat FSH but not by rat LH. The Scatchard plot analyses of the binding of FSH to the testicular preparations of fetuses showed straight lines similar to those of postnatal rats, suggesting the presence of a single class of binding sites. The mean dissociation constant (Kd) for FSH receptors in 17.5-day fetuses was 0.413 +/- 0.043 nM, which was significantly greater than that in postnatal rats at 50 days of age. However, the Kd in 19.5-day fetuses was not significantly different from those in 17.5-day fetuses and postnatal rats due to its considerable variance. The capacity of FSH binding sites was 0.51 +/- 0.01 fmol/testis in 17.5-day fetuses, which was significantly less than those of 19.5-day fetuses and postnatal rats. 相似文献
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14.
Y C Kong W M Keung T T Yip K M Ko S W Tsao M H Ng 《Comparative biochemistry and physiology. B, Comparative biochemistry》1987,87(2):221-226
1. An epidermal growth factor (EGF)-like activity was detected and partially purified from swiftlet's nest extract. 2. The partially purified EGF-like activity was able to (a) generate competitive binding curves parallel to the standard curves in radioreceptor assay and (b) stimulate thymidine incorporation in quiescent culture of 3T3 fibroblasts and the latter activity can be suppressed by mouse EGF antibody. 3. Partial characterization of the EGF-like activity in terms of pI, molecular weight and its behavior on gel filtration column suggest that it bears similar physical properties to the EGFs isolated from the mouse and the shrew. 相似文献
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16.
Hideki Takahashi Ko Shimamoto Yoshio Ehara 《Molecular & general genetics : MGG》1989,216(2-3):188-194
Summary In order to study possible functions of the inclusion body matrix protein (IBMP) encoded by gene VI of cauliflower mosaic virus (CaMV), the XbaI fragment containing the gene VI of a Japanese strain of CaMV (CaMV S-Japan) was transferred to tobacco plants by Ti mediated transformation. Eight out of 18 kanamycin resistant plants (40%) expressed detectable levels of IBMP. Those transgenic plants expressing IBMP produced leaves with light green color, and their growth was suppressed as compared with control plants. Symptom-like necrotic spots also appeared on the leaves and stems of the mature transgenic plants. Furthermore, in these transgenic plants, pathogenesis-related proteins 1a, 1b and 1c were highly expressed and the activity of 1,3--glucanase was increased up to eightfold. From these results, we concluded that expression of the IBMP is associated with symptom development. 相似文献
17.
S Filipecki B Vertun-Baranowska J Müller W Pokojski B Hajduk A Radomyski W Tomkowski P Ko?b Z Polowiec 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1989,44(2-3):36-41
Controlled oxygen-therapy was used in 30 out of 49 patients (61%) with the acute respiratory failure or exacerbations of the chronic respiratory failure treated at ICU (Group Y), while artificial ventilation in the remaining 19 patients (39%; Group B). An improvement was achieved in 70% of patients of Group A and 42% in Group B. Overall improvement was achieved in 59% of the treated patients. There were 69% of treated patients with infections. Totally 41% of the treated patients died (30% of Group A and 58% of Group B). An analysis of the results has been carried out in various subgroups of the treated patients, i.e. the acute and exacerbated respiratory failure as well as partial and complete respiratory insufficiency. The result of high risk patients have also been analysed. This subgroup included sudden cardiac arrest, shock and non-compensated acidosis. Favourable effects of the intensive care of patients with infections have been discussed with particular reference to the life hazard in case of septic complications. Emphasis is on the unfavorable effects of therapy in patients with respiratory failure complicated with pulmonary embolism. Indications to the use of respirator and complications of the artificial ventilation have been discussed. 相似文献
18.
It is known that several materials used in semen collection have been found to be detrimental to spermatozoal motility. In this study, examinations for toxic effects of latex and vinyl gloves, used with and without talcum powder on boar spermatozoa, were performed. Ten boars of known fertility with >/=80% sperm motility were divided into two groups (n = 5 boars each) for in vitro and in vivo studies. In the in vitro study, semen was collected from each of the five boars and was divided into five separate aliquots (5 ml each). One aliquot from each of the boars remained as the control, while the remaining aliquots were divided into individual treatments exposing the semen to a l cm(2) piece of latex or vinyl glove with or without talcum powder. In the in vivo experiment, semen from each of the five boars was collected using a gloved hand. During collection, the first half of the sperm-rich fraction was collected into a filtered sterile container, while the second half of the fraction was allowed to run through the palm of either a latex or vinyl powdered glove prior to collection in the container. In both experiments, semen sample motility was assessed by two independent observers at 1 minute after exposure. Results of both experiments consistently showed a significant (P<0.05) effect of latex gloves (with or without talcum powder) on boar semen when compared with the control semen. Motility was at or near 0% at 1 min after exposure to latex. No significant difference (P>0.05) in motility was observed between the control semen and the semen exposed to talcum powdered vinyl gloves. These results show that latex gloves are detrimental to boar spermatozoa. Therefore, it is suggested that when collecting boar semen vinyl gloves should be used. 相似文献
19.
Eighty crossbred, multiparous sows, weighing between 190 and 320 kg, were randomly assigned to the following four treatment groups of 20 sows each: 1) saline-saline, 2) cloprostenol-saline, 3) saline-xylazine and 4) cloprostenol-xylazine. The mean gestation length of each multiparous sow was calculated. Cloprostenol (250 ug/sow, i.m.) or saline was given 3 d prior to the calculated due date at 11:30 a.m. Xylazine (2 mg/kg, i.m.) or saline was given 20 h after either the cloprostenol or previous saline treatment. Cloprostenol-xylazine treated sows had the shortest mean farrowing interval (1.5 +/- 0.3 h) when compared with the rest of the treatment groups (saline-saline:66.0 +/- 8.1, cloprostenol-saline:10.5 +/- 1.9, saline-xylazine:60.6 +/- 5.6 h). Farrowing time, percentage of stillbirths, average birth weight, d-5 and d-21 postbirth weights, number of pigs born, number of pigs born alive, and number of pigs surviving at 5 and 21 d afterbirth were not significantly different among the four groups. This study demonstrated that cloprostenol-xylazine treatment decreases the time to onset of farrowing with less variation than cloprostenol or xylazine alone. Therefore, the use of a cloprostenol-xylazine combination is suggested as an alternative method for inducing farrowing. 相似文献
20.
Human erythrocyte membranes which had been thoroughly extracted with organic solvents contained 20 nmol of fatty acids/mg dry wt. The major fatty acids were palmitic and stearic with their monoethenoic derivatives as minor constituents. No other fatty acids were detected. When solvent-extracted membranes were digested with Pronase about 90% of the original content of fatty acids was retained in the insoluble residue. Fatty acids were linked to membrane proteins through alkali-labile bonds of which 30% were of a thiol ester and the remainder of an O-ester type. This conclusion is based on differential liberation of fatty acids by hydroxylamine at pH 7.0 and pH 11.0. Two extracts of membranes enriched in peripheral proteins (bands 1, 2, 5 and 2.1, 4.1, 4.2, 6) were prepared and extracted with organic solvents but each contained about six times less fatty acids than the parent solvent-extracted membranes. Glycophorin A contains little if any covalently bound fatty acids. Anion transporter (band 3) contains about 1 mol of thiol ester of fatty acid. This accounts for about half of the thiol ester-linked fatty acids in the parent solvent-extracted membranes. Most of the O-ester-linked fatty acids are linked to an undisclosed membrane protein. 相似文献