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51.
During late pregnancy in rats, ovarian secretion of progesterone decreases and that of its reduced metabolite, 20 alpha-hydroxypregn-4-en-3-one (20 alpha-OHP), increases. The present study was undertaken to determine whether changes in ovarian blood flow are consistent with changes in progestin secretion. Rats (n = 5 per group) were examined on Day 16, the time of maximal progesterone secretion, and in the morning (AM) and afternoon (PM) of Day 22, the day prior to parturition. Ovarian blood flow was monitored continuously for 60 to 80 min, and serial samples of arterial and ovarian venous blood were obtained at 20-min intervals for determination of ovarian secretion rates of progesterone and 20 alpha-OHP. Ovarian blood flow increased from 0.38 +/- 0.04 ml/min (mean +/- SEM) on Day 16, to 0.77 +/- 0.05 and 0.78 +/- 0.04 ml/min on Day 22 AM and PM, respectively, whereas the secretion of progesterone decreased from 26.9 +/- 4.0 to 4.5 +/- 1.0 and 3.2 +/- 0.3 micrograms/h per ovary. The secretion of 20 alpha-OHP was similar on Day 16 and Day 22 AM (5.6 +/- 1.7 and 5.4 +/- 1.3 micrograms/h per ovary) but then increased to 18.9 +/- 1.2 micrograms/h per ovary by Day 22 PM. Thus the amount of total progestins secreted per unit rate of blood flow relative to that on Day 16 (100%) fell to 15% and 34% on the morning and afternoon of Day 22, respectively. Clearly, the relative changes in ovarian progestin secretion and blood flow in the rat near term to not conform to patterns observed at luteal regression in some other species.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Two groups of critically ill patients were transferred by ambulance from other hospitals to a central intensive therapy unit. The effect of transport was reviewed retrospectively in 46 patients and prospectively in 20 patients. Of the 46 patients reviewed retrospectively six became hypotensive, six became hypertensive, and seven developed delayed hypotension. One patient developed fits and six out of 13 patients had a rise in arterial PCO-2 of 1-6-4-1 kPa (12-31 mm Hg). Of the 20 patients reviewed prospectively, one patient became hypertensive due to overtransfusion, one had a fit, but none became hypotensive. Three out of four cases of delayed hypotension were related to starting intermittent positive pressure ventilation. Arterial PCO-2 fell in one patient and arterial PCO-2 rose in two, each change being related to changed oxygen therapy or narcotics. There were no changes in other cardiovascular or respiratory indices, body temperature, or urine production. Earlier transfer, resuscitation before transfer, continuing medical care during the journey, and hence a slower smoother journey seemed to be important factors in the management of these patients. Our findings, may have important implications in the future regional organization of the care of critically ill patients.  相似文献   
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BACKGROUND: The vaginal vault smear is a test for cellular atypia in women who have undergone a hysterectomy. In asymptomatic women the test has poor sensitivity and specificity. Current guidelines recommend: vault smears should not be used after hysterectomy for benign pathology; two vault smears (6 and 12 months postsurgery) should be taken when there is evidence of completely excised CIN II/III in the specimen. AIM: To describe primary health care professionals' self-reported knowledge and behaviour relating to the use of vault smears. DESIGN OF STUDY: Questionnaire. SETTING: South Birmingham. METHODS: Postal questionnaire survey to primary health care professionals (general practitioners and practice nurses, n = 424). Results: Response rate 80.0%, completed response rate 68.9%. Mean knowledge score was 7.3 out of possible 12 (SD 1.9); range 0-10. No significant differences were observed between GPs and practice nurses in knowledge scores, although differences were noted in the frequency of performing vault smears. An inverse relationship was observed between frequency of performing vault smears and level of knowledge about the test. There was a positive association between requesting further information and the 'knowledge score'. Only 11% correctly answered a question based on current guidelines. CONCLUSIONS: Knowledge of current guidelines was poor. Those who undertook fewest vault smears appeared best informed. This suggests that if all primary care professionals practised according to current guidelines, the number of vault smears performed may be reduced. Unnecessary vault smears may cause additional anxiety in women and have financial consequences for the NHS.  相似文献   
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Background

Halibuts are commercially important flatfish species confined to the North Pacific and North Atlantic Oceans. We have determined the complete mitochondrial genome sequences of four specimens each of Atlantic halibut (Hippoglossus hippoglossus), Pacific halibut (Hippoglossus stenolepis) and Greenland halibut (Reinhardtius hippoglossoides), and assessed the nucleotide variability within and between species.

Results

About 100 variable positions were identified within the four specimens in each halibut species, with the control regions as the most variable parts of the genomes (10 times that of the mitochondrial ribosomal DNA). Due to tandem repeat arrays, the control regions have unusually large sizes compared to most vertebrate mtDNAs. The arrays are highly heteroplasmic in size and consist mainly of different variants of a 61-bp motif. Halibut mitochondrial genomes lacking arrays were also detected.

Conclusion

The complexity, distribution, and biological role of the heteroplasmic tandem repeat arrays in halibut mitochondrial control regions are discussed. We conclude that the most plausible explanation for array maintenance includes both the slipped-strand mispairing and DNA recombination mechanisms.  相似文献   
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