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21.
Detecting pre-ovulatory luteinizing hormone surges in urine 总被引:2,自引:1,他引:2
Kesner JS; Knecht EA; Krieg EF Jr; Wilcox AJ; O'Connor JF 《Human reproduction (Oxford, England)》1998,13(1):15-21
The study objectives were to determine (i) if pre-ovulatory luteinizing
hormone (LH) surges, undetected in urine by two immunoradiometric assays
(IRMA), were detectable by an ultrasensitive immunofluorometric assay
(IFMA) and (ii) the influence of creatinine adjustment on the detection and
timing of the urinary LH surges. Daily urine specimens were contributed by
healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for
an epidemiological study conducted in 1983-1985. Specimens were selected as
having been previously assayed by two IRMA without consistently detecting
LH surges. These urine specimens were remeasured using an IFMA and adjusted
for creatinine concentration. IFMA measurements revealed unambiguous LH
surges in all cycles. Adjusting IRMA urinary LH values for creatinine
concentrations revealed previously undetected LH surges in four of eight
cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH
surges by 1-5 days. These results demonstrate an IFMA that detects pre-
ovulatory LH surges in unpreserved, frozen urine from cycles where such
surges were previously undetectable. Further, creatinine adjustment can
markedly affect detection and timing of the onset and peak of the urinary
LH surge. While our analysis suggests that this adjustment improves the
validity of the LH measure, this requires further investigation.
相似文献
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This study compared the responses of ventral and dorsal premotor cortex (PMv and PMd) neurons to predictable force-pulse perturbations applied during a precision grip. Three monkeys were trained to grasp an unseen instrumented object between the thumb and index finger and to lift and hold it stationary within a position window for 2-2.5 s. The grip and load forces and the object displacement were measured on each trial. Single-unit activity was recorded from the hand regions in the PMv and PMd. In some conditions a predictable perturbation was applied to the object after 1,500 ms of static holding, whereas in other conditions different random combinations of perturbed and unperturbed trials were given. In the perturbed conditions, some were randomly and intermittently presented with a warning flash, whereas some were unsignaled. The activities of 198 cells were modulated during the task performance. Of these cells, 151 were located in the PMv, and 47 were located in the PMd. Although both PMv and PMd neurons had similar discharge patterns, more PMd neurons (84 vs. 43%) showed early pregrip activity. Forty of 106 PMv and 10/30 PMd cells responded to the perturbation with reflexlike triggered reactions. The latency of this response was always <100 ms with a mean of about 55 ms in both the PMv and the PMd. In contrast, 106 PMv and 30 PMd cells tested with the perturbations, only 9 and 10%, respectively, showed significant but nonspecific adaptations to the perturbation. The warning stimulus did not increase the occurrence of specific responses to the perturbation even though 21 of 42 cells related to the grip task also responded to moving visual stimuli. The responses were retinal and frequently involved limited portions of both foveal and peripheral visual fields. When tested with a 75 x 5.5-cm dark bar on a light background, these cells were sensitive to the direction of movement. In summary, the periarcuate premotor area activity to related to predictable force-pulse perturbations seems to reflect a general increase in excitability in contrast to a more specific anticipatory activity such as recorded in the cerebellum. In spite of the strong cerebello-thalamo-cortical projections, the results of the present study suggest that the cortical premotor areas are not involved in the elaboration of adaptive internal models of hand-object dynamics. 相似文献
24.
F Boudreau 《Canada's mental health》1986,34(1):16-18
The author offers a few reflections on the theme of the recent symposium of the Quebec Hospital Association: "De l'espoir à la Réalité" ("From Hope to Reality"). Twenty-five years after the report on quebec's psychiatric hospitals, what has become of the hopes and concerns of that time? Through all the changes that have occurred--from the hopes inherited from 1960 to the hopes articulated in the 1980s; from the "outmoded" realities of the institutional model to the realities considered "the way of the future", based on an ecological or bio-psycho-culturo-social model; from the preoccupations of the asylum to those of "mental health"--a fundamental question remains: Is the patient any better off? One might add a second question: WHich 'patient' are we referring to? 相似文献
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Jacques H Gascon A Arul J Boudreau A Lavigne C Bergeron J 《The American journal of clinical nutrition》1999,70(6):983-991
BACKGROUND: A modified milk fat with reduced cholesterol was developed by fractionation technology. OBJECTIVE: The effect of this modified milk fat on the lipoprotein profile of 21 normolipidemic men was compared with that of regular milk fat and nonhydrogenated margarine. DESIGN: A crossover design was used for the administration of the 3 experimental diets, which provided 13240 kJ as 16% protein, 51% carbohydrates, 33-34% lipids, and 21 g fiber/d. The ratio of polyunsaturated to saturated fat was 1.3:1 for the margarine diet and 0.3:1 for the milk-fat diets. The cholesterol content of the modified milk-fat and margarine diets was similar (248 and 254 mg/d, respectively), but was significantly higher (428 mg/d) for the regular milk-fat diet. RESULTS: Modified and regular milk fats did not change plasma total and LDL cholesterol significantly, but margarine did (P < 0.01). Furthermore, modified milk fat maintained initial HDL(2)-cholesterol concentrations, but margarine reduced this variable significantly (P < 0.05). These results can be explained by the lower ratio of polyunsaturated to saturated fat in the modified and regular milk-fat diets than in the margarine diet. Men who ingested modified milk fat had significantly (P < 0.05) lower total and VLDL-triacylglycerol and VLDL-cholesterol concentrations than did those who ingested either regular milk fat or margarine. This may have been, in part, because of the lower intestinal fat absorption with modified milk fat than with regular milk fat and margarine arising from changes in the melting properties of milk fat with fractionation. CONCLUSION: A reduction in plasma triacylglycerol concentrations after the consumption of modified milk fat may prevent the onset of hypertriacylglycerolemia. 相似文献
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Eileen M. Dryden PhD Meaghan A. Kennedy MD MPH Jennifer Conti MPH Jacqueline H. Boudreau MPH Chitra P. Anwar MA Kathryn Nearing PhD MA Camilla B. Pimentel PhD MPH William W. Hung MD MPH Lauren R. Moo MD 《Health services research》2023,58(Z1):26-35