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41.
Diego Nuñez Jr. M.D. John D. Wester M.D. Kimberley A. Lentz M.D. Marco A. Amendola M.D. 《Emergency radiology》1996,3(1):20-24
This study was performed to evaluate whether consecutive arterial phase and portal venous phase scans of the upper abdomen are contributory in the evaluation of the liver in patients with blunt abdominal trauma. The purpose of the study was to determine whether such dual acquisition using helical computed tomography (HCT) provides improved definition of injuries and significant information about the dynamics of posttraumatic hemorrhage.During a 10-month period, all patients referred for evaluation of blunt abdominal trauma were scanned using a dual phase imaging technique. Two consecutive and comparable scan clusters were programmed to study the upper abdomen, with a slice collimation of 10 mm and a 11 pitch. Intravenous contrast medium was delivered at a rate of 2 ml/sec for a total of 125 ml, with scan delays of 30 and 70 seconds (arterial and venous phases of hepatic enhancement).Thirty-two patients with hepatic lacerations were encountered, and the images from both acquisitions were compared and graded according to lesion conspicuity. The presence of contrast medium extravasation associated with parenchymal injuries was also recorded.In 23 (72%) of the 32 patients, the liver injuries were better defined in the portal venous phase, and in eight (25%) patients, the lesions were equally shown in both phases. In only one case, the lesion was better demonstrated in the arterial phase. Contrast medium extravasation was noted in two patients at the site of liver laceration. In three additional cases, contrast medium extravasation was also noted in associated splenic injuries. In all of these patients, the extravasation (bleeding laceration) was seen only in the images corresponding to the portal venous phase.Dual phase HCT of the upper abdomen does not provide significant additional information in the evaluation of patients with liver injuries resulting from blunt abdominal trauma. With a single scan cluster through the upper abdomen after a 70-second injection-scan delay, lesion definition is optimal, and vascular opacification remains adequate. 相似文献
42.
Sood PK Cooper PJ Michel MZ Wee MY Pickering RM 《International Journal of Obstetric Anesthesia》1996,5(3):172-175
This study was carried out to determine whether the use of thrombo-embolic deterrent (TED) stockings, in combination with an intravenous crystalloid preload, would prevent hypotension following spinal anaesthesia for caesarean section. Fifty parturients undergoing elective caesarean section under spinal anaesthesia were randomly allocated into two groups. TED stockings were applied to the study group 1 h before spinal anaesthesia but none were applied to the control group. Both groups received a crystalloid preload of 15 ml kg(-1) over 15 min before spinal injection. Significant hypotension, defined as an absolute value of systolic arterial pressure (SAP) of less than 90 mmHg and a decrease of more than 20% from baseline SAP was treated with 3 mg bolus of ephedrine as required. The difference in SAO between the two groups was not statistically significant. In the control group, 80% of parturients required ephedrine as opposed to 56% in the TED group; a difference that was also not statistically significant. 相似文献
43.
44.
P L Schnall P A Landsbergis C F Pieper J Schwartz D Dietz W Gerin Y Schlussel K Warren T G Pickering 《American journal of industrial medicine》1992,21(3):417-432
The impact of occupational stressful life events on psychological distress and blood pressure was examined among employees of a major New York City brokerage firm undergoing massive layoffs. One hundred thirty-nine employees of the firm, who had participated in a blood pressure screening in 1986, were rescreened during the period of layoffs within their company in 1989. About two-thirds of the 139 employees reported being "somewhat" or "very" anxious or upset in 1989 during the period of layoffs, and psychological distress was significantly elevated among those employees reporting possible or definite layoff or job change and/or difficulty in obtaining a comparable job. However, we found no increase in overall blood pressure level, and no effect of anticipation of job loss on 1989 blood pressure when controlling for 1986 blood pressure level, age, body mass index, work hours, and other demographic variables. On the other hand, employment in a department sold to another employer on the day of screening, as well as employment in a clerical job title, were both associated with significant increases in diastolic blood pressure of about 5 mm Hg. 相似文献
45.
In the absence of large, prospective, quality randomized trials, there remains tremendous debate concerning the optimal management of patients with renal vascular disease. This debate is compounded by the fact these patients do not represent a homogeneous group; different causes and presentations each carry a different prognosis and potential response to therapy. Therapeutic options include medical management, surgery, or percutaneous approaches (angioplasty or stenting). This review examines the results of observational studies of medical and percutaneous therapies for blood pressure control and preservation of renal function. Generally, in patients with fibromuscular disease, the results of percutaneous management are superior to medical therapy. Although these observational studies are difficult to compare, in patients with atheromatous disease, the results with interventional and medical therapy appear roughly similar. There have been three randomized prospective trials of routine angioplasty versus medical management. These trials show little advantage to interventional therapies in those patients whose blood pressure is well controlled with medication who do not show progression of renal insufficiency during medical management. Based on these data, this review outlines a potential management strategy that relies on an individualized risk benefit assessment. 相似文献
46.
47.
Michael Ambler Timna Hitrec Andrew Wilson Matteo Cerri Anthony Pickering 《The Journal of neuroscience》2022,42(21):4267
Torpor is a naturally occurring, hypometabolic, hypothermic state engaged by a wide range of animals in response to imbalance between the supply and demand for nutrients. Recent work has identified some of the key neuronal populations involved in daily torpor induction in mice, in particular, projections from the preoptic area of the hypothalamus to the dorsomedial hypothalamus (DMH). The DMH plays a role in thermoregulation, control of energy expenditure, and circadian rhythms, making it well positioned to contribute to the expression of torpor. We used activity-dependent genetic TRAPing techniques to target DMH neurons that were active during natural torpor bouts in female mice. Chemogenetic reactivation of torpor-TRAPed DMH neurons in calorie-restricted mice promoted torpor, resulting in longer and deeper torpor bouts. Chemogenetic inhibition of torpor-TRAPed DMH neurons did not block torpor entry, suggesting a modulatory role for the DMH in the control of torpor. This work adds to the evidence that the preoptic area of the hypothalamus and the DMH form part of a circuit within the mouse hypothalamus that controls entry into daily torpor.SIGNIFICANCE STATEMENT Daily heterotherms, such as mice, use torpor to cope with environments in which the supply of metabolic fuel is not sufficient for the maintenance of normothermia. Daily torpor involves reductions in body temperature, as well as active suppression of heart rate and metabolism. How the CNS controls this profound deviation from normal homeostasis is not known, but a projection from the preoptic area to the dorsomedial hypothalamus has recently been implicated. We demonstrate that the dorsomedial hypothalamus contains neurons that are active during torpor. Activity in these neurons promotes torpor entry and maintenance, but their activation alone does not appear to be sufficient for torpor entry. 相似文献
48.
IntroductionResearch, theory, and popular belief all suggest that penile sensation is greater in the uncircumcised as compared with the circumcised man. However, research involving direct measurement of penile sensation has been undertaken only in sexually functional and dysfunctional groups, and as a correlate of sexual behavior. There are no reports of penile sensation in sexually aroused subjects, and it is not known how arousal affects sensation. In principle, this should be more closely related to actual sexual function.AimThis study therefore compared genital and nongenital sensation as a function of sexual arousal in circumcised and uncircumcised men.MethodsTwenty uncircumcised men and an equal number of age-matched circumcised participants underwent genital and nongenital sensory testing at baseline and in response to erotic and control stimulus films. Touch and pain thresholds were assessed on the penile shaft, the glans penis, and the volar surface of the forearm. Sexual arousal was assessed via thermal imaging of the penis.ResultsIn response to the erotic stimulus, both groups evidenced a significant increase in penile temperature, which correlated highly with subjective reports of sexual arousal. Uncircumcised men had significantly lower penile temperature than circumcised men, and evidenced a larger increase in penile temperature with sexual arousal. No differences in genital sensitivity were found between the uncircumcised and circumcised groups. Uncircumcised men were less sensitive to touch on the forearm than circumcised men. A decrease in overall touch sensitivity was observed in both groups with exposure to the erotic film as compared with either baseline or control stimulus film conditions. No significant effect was found for pain sensitivity.ConclusionThese results do not support the hypothesized penile sensory differences associated with circumcision. However, group differences in penile temperature and sexual response were found. Payne K, Thaler L, Kukkonen T, Carrier S, and Binik Y. Sensation and sexual arousal in circumcised and uncircumcised men. 相似文献
49.
P.C. Elwood Janet Pickering J. Yarnell J.R. O'Brien Y. Ben Shlomo P. Bath 《Platelets》2013,24(3):139-141
The stressed bleeding time is a simple 'global' test of haemostasis, dependent upon platelet function, rheology, thrombosis and intimal function. It could be of considerable value in clinical practice if it were shown to be predictive of vascular disease events. A stressed bleeding time test was done on 1319 men aged 55-69 years in the Caerphilly Cohort Study of Heart Disease, Stroke and Cognitive Decline. The men were followed-up and during the following 7-10 years 155 men had a myocardial infarction (MI) and 72 an ischaemic stroke. The mean bleeding time was 323 (SD 113) s. This was shorter in men who smoked by an average of 45 s, and lengthened in men who took aspirin daily by 40 s. After making statistical adjustments for numerous possible confounding factors, the relative odds (ROs) of an MI within the third of men with the longest bleeding times, compared to the third with the shortest times, was 0.90 (0.40-2.03). For ischaemic stroke, the ROs in the third of men with the longest times were 1.42 (0.39-5.21). The stressed bleeding time does not predict either MI or ischaemic stroke. It has no place in health screening. 相似文献