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Six malo-lactic strains of lactic acid bacteria were isolated from California wines and identified as Lactobacillus delbrueckii, L. buchneri, L. brevis, Leuconostoc citrovorum, and two strains of Pediococcus cerevisiae. Malo-lactic fermentation was induced in separate lots of wine by inoculation of each lot with one of the strains of bacteria. Malo-lactic fermentation had occurred in each inoculated wine within 2 months. The resultant wines were subjected to chemical analysis, including gas chromatographic examination of concentrated extracts of the wines. Only a few differences in composition were found when the malo-lactic wines were compared one with another. The differences that were found were in volatile acidity and in concentrations of acetoin (plus diacetyl) and probably diethyl succinate.  相似文献   
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Ring cleavage of atrial natriuretic peptide (ANF) between Cys7 and Phe8 by endoprotease 3.4.24.11 yields X-ANF. Since endoprotease 3.4.24.11 may contribute to ANF metabolism in vivo, the present study determined if X-ANF exhibits reduced biological activity in comparison to the parent molecule.  相似文献   
76.
OBJECTIVES--To determine the symptomatic and urodynamic outcome of elective prostatectomy and to establish whether the outcome is influenced or can be predicted by preoperative urodynamic measurements. DESIGN--Prospective non-randomised study with follow up at a mean of 11 months after operation. Most men were assessed jointly by a urologist and a general practitioner. SETTING--Department of urology in a teaching hospital serving a large district population. PATIENTS--253 Men listed for elective prostatectomy because of symptoms and low urinary flow rates (less than 15 ml/s) and excluding those already on a waiting list or with acute urinary retention, clinically apparent prostatic cancer, and neurological or cerebrovascular disease; 217 (86%) were followed up. INTERVENTION--Elective prostatectomy. MAIN OUTCOME MEASURE--Classification on the basis of relief of symptoms assessed by patients and urologist and general practitioner and of symptom scores obtained by questionnaire. RESULTS--Of the 217 men followed up, 171 (79%) had a satisfactory subjective review and 155 (72%) had a satisfactory review and also low symptom scores. An unsatisfactory outcome was associated with preoperative symptoms of urge incontinence, small prostatic size and resected weight, low voiding pressures, and low urethral resistance. Preoperative maximum urinary flow rates did not predict outcome. Men with poor outcome could be classified into two groups: those with irritative symptoms who were more likely before operation to have had urge incontinence and detrusor instability and men with symptoms of poor urinary flow who were more likely before operation to have had a small prostate, low voiding pressures, and low urethral resistance. In patients in the second group flow rates or voiding pressures improved little after operation. Men with stable detrusors and either low urethral resistance or low voiding pressures were less likely to do well after prostatectomy, but despite these associations preoperative urodynamic measurements were unable to predict outcome accurately. CONCLUSIONS--Prostatectomy was satisfactory in relieving symptoms and improving urodynamic measurements in most men, but even in those with classic symptoms and low urinary flow rates a substantial minority experienced little improvement afterwards and urodynamic measurements did not accurately predict outcome in individual patients.  相似文献   
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A high and a low response line in sheep were selected on the basis of the mean concentration of LH in 10-week-old Finn-Dorset ram lambs after an i.v. injection of 5 micrograms GnRH. After 8 male generations the mean LH response of the high line was more than 5-fold that of the low line and the heritability of the selected trait was estimated at 0.44 +/- 0.015. Highly significant line differences in mean LH response to GnRH were also found in males at 20 weeks of age and females at 10 and 20 weeks of age and the genetic correlations between the four LH response traits appear to be close to unity. Large line differences in the mean FSH response to GnRH were also found in both males and females at 10 and 20 weeks of age. Selection had little effect on the physical characteristics of lambs. High-response line ewes entering their first breeding season at about 7 months of age showed oestrus earlier in the season and had higher ovulation rates and numbers of lambs born per ewe lambing than did low-response line ewes. In the second breeding season, at about 19 months of age, the only line difference was a higher ovulation rate early in the breeding season in high-line ewes. It is suggested that these changes may be mediated by a more rapid response in high-line ewes to increased GnRH stimulation at puberty or at the beginning of the breeding season.  相似文献   
79.
Ovarian response to hCG treatment during the oestrous cycle in heifers   总被引:2,自引:0,他引:2  
The aims of this study were to investigate whether treatment with a single ovulatory dose of hCG, between the day of oestrus and the end of the luteal phase, could induce extra ovulations in heifers and whether the presence of an existing corpus luteum (CL) affected the response. Heifers (N = 32) were injected with 1500 i.u. hCG or saline on a given day of the oestrous cycle. Treatments were repeated during subsequent cycles to provide a total of 71 observations, 57 of which followed an injection of hCG, given between Day 0 (oestrus) and Day 16, and 14 of which followed saline injections as controls. Ovulatory responses were noted by laparoscopy 2 days after hCG treatment. No heifers injected with saline produced additional CL. Of the hCG-treated cycles, 23 resulted in the formation of an additional CL, and this was significantly affected by the stage of the oestrous cycle when hCG was given; a greater response was observed during the early (Days 4-7) and late (Days 14-16) stages of the luteal phase than at the mid-luteal phase of the oestrous cycle. Two heifers were also treated with hCG on Days 17 or 18 of the oestrous cycle, but before oestrus; both had induced CL. There were no significant differences between the left-right orientation of the existing CL or the hCG-induced CL. These results demonstrate that the large, luteal-phase follicle of the cow is capable of ovulating in response to hCG and that the induced CL is not affected by the presence of an existing CL.  相似文献   
80.
A Folta  I G Joshua  R C Webb 《Life sciences》1989,45(26):2627-2635
Endothelin has been characterized as a potent constricting factor. The purpose of this study was to investigate possible dilator effects of this peptide and to examine whether dilator responses occur through an endothelium-mediated mechanism in guinea pig coronary resistance vessels and isolated aortic rings. Changes in perfusion pressure after bolus injections of endothelin were measured using a constant-flow modified Langendorff preparation with a transducer between the flow pump and the heart. An immediate fall in perfusion pressure, averaging 6 mmHg, was observed after injection of endothelin (10(-14)-10(-12) moles). This effect was maximal at 1 minute and tended to return toward baseline levels within 4 minutes. In response to endothelin (10(-9) M), isolated aortic rings relaxed 35% after being contracted with prostaglandin F2 alpha (10(-7) M). In both preparations, dilation was converted to constriction after endothelium damage by oxygen radicals or endothelium removal (mechanical rubbing). Dilator responses to endothelin were blocked by pretreatment for 30 minutes with indomethacin (14 microM) in the presence of an intact endothelium in coronary resistance vessels, whereas in the abdominal aorta they were not. We conclude that endothelin has significant dilator properties and that this effect is opposed by its constrictor action at higher doses. In addition, dilator responses to endothelin require an intact endothelium in both coronary vessels and abdominal aorta. Finally, endothelin-induced dilation in coronary resistance vessels appears to occur through a cyclooxygenase product-mediated mechanism.  相似文献   
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