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11.
Previously reported attenuation of skin postural vasoconstriction in women during the luteal menstrual cycle phase may be
due to a progesterone-mediated decrease in myogenic or veno-arteriolar (VAR) mechanisms. Skin perfusion was measured in the
shin and foot dorsum by Laser Doppler Fluxometry during leg dependency that increased vascular transmural pressure below (myogenic
constriction only) and above (myogenic and VAR) the 25 mmHg threshold for activation of the VAR, and during venous distension
to activate the VAR alone (cuff inflation to 50 mmHg). In six young women with normal menstrual cycles, vasoconstrictor responses
to all interventions did not differ between days 7–13 (follicular) and 18–23 (luteal) of the normal menstrual cycle when progesterone
levels were low and at their peak respectively. In eight women taking combined oral contraceptives (OC) and tested during
pill consumption days, reductions in foot skin perfusion were smaller (P = 0.05) than in the luteal phase of the normal cycle for leg dependency below (−36.9 ± 5.2% OC vs. −52.5 ± 7.8% luteal, mean ± S.E.M.)
and above (−43.7 ± 3.4% OC vs. −55.1 ± 4.8% luteal) the VAR threshold, and for venous distension (−53.1 ± 2.6% OC vs. 66.4 ± 5.5%
luteal). In women with normal menstrual cycles, impaired postural vasoconstriction may be confined to those who experience
pre-menstrual symptoms rather than a direct effect of endogenous hormones. Reduced vasoconstriction in the dependent foot
during OC use is consistent with the known vasodilator action of exogenous hormones and its long-term effects 相似文献
12.
SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy 相似文献
13.
J R Bishop J W Moul S A Sihelnik D S Peppas T S Gormley D G McLeod 《The Journal of urology》1992,147(2):386-388
We report an 18-month prospective study of 90 patients undergoing penile prosthesis implantation to evaluate a possible cause-and-effect relationship between degree of diabetic control and the risk of infection complicating the operation. Long-term diabetic control was objectively evaluated by measurement of the glycosylated hemoglobin of the patient, which is known to provide an objective value for degree of control for the preceding 60 to 90 days. Of 90 patients 5 (5.5%) had a periprosthetic infection requiring explantation and all infections occurred in the 32 diabetics (36%) in the population (p less than 0.009). Of the 32 diabetics 13 (41.1%) were poorly controlled with time as demonstrated by a glycosylated hemoglobin level of greater than 11.5% and 4 of the infections occurred in this group. Of the 19 remaining controlled diabetics (glycosylated hemoglobin level less than 11.5%) only 1 infection occurred. Therefore, infection occurred in 31% of the poorly controlled versus 5% of the adequately controlled patients (p less than 0.0003). Measurement of glycosylated hemoglobin values appears to be a useful tool to evaluate diabetic patients before implantation of a penile prosthesis. Patients with a glycosylated hemoglobin level of 11.5% or greater should be more optimally controlled before undergoing implantation in an effort to avoid infectious complications. 相似文献
14.
Cholinergically induced bronchoconstriction is thought to be a major cause of bronchospasm during anesthesia. We used tracheally intubated rabbits (4-mm endotracheal tube) stimulated with methacholine to assess the efficacy of beta-adrenergic agonist and anticholinergic treatment in reversing the increases in respiratory system resistance. Four groups were compared: (a) inhaled metaproterenol, 20 puffs via metered dose inhaler (0.65 mg/puff); (b) inhaled ipratropium bromide, 20 puffs from a metered dose inhaler (18 micrograms/puff); (c) 2 mg of intravenous atropine; and (d) no treatment after methacholine challenge as a control group. Methacholine increased respiratory system resistance from 0.041 +/- 0.001 (mean +/- SEM) to 0.098 +/- 0.006 cm H2O.mL-1.s-1 (P < 0.001). Whereas beta-adrenergic agonist treatment was ineffective in ameliorating bronchoconstriction, inhaled ipratropium bromide and atropine were highly effective, causing an 86%-88% reversal in the methacholine-induced increase in respiratory system resistance. Both these agents were also effective in improving dynamic compliance. We conclude that inhaled ipratropium bromide is effective in treating cholinergic bronchospasm even when administered via a small endotracheal tube and that the beta-adrenergic agonist metaproterenol is ineffective in rabbits in the face of maximal cholinergic stimulation. 相似文献
15.
R Snyder J Bishop G Brodie W Burns A Coates J Levi D Raghavan M Schwarz M Tattersall D Thomson 《Cancer treatment reports》1987,71(3):273-276
Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin. 相似文献
16.
M G Bishop 《Journal of the Royal Society of Medicine》1992,85(5):249-252
17.
18.
Jonathan E. Bishop Giles E. Santyr Frederick Kelcz Donald B. Plewes 《Journal of magnetic resonance imaging : JMRI》1997,7(4):716-723
The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction. 相似文献
19.
Cystic fibrosis patients born with meconium ileus (MI) have had an improved outcome over the last three decades. The authors reviewed the impact of surgical management and long-term nutritional care on the survival of patients with MI. Of the 59 cases of MI seen from 1959 to 1989, 48 cases were managed operatively using either the Bishop-Koop ileostomy (BK), the Mikulicz ileostomy, primary resection and anastomosis (RA), or ileostomy. Six-month survival of MI has improved from 37% to 100%. Nonoperative cases (n = 11) had 100% long-term survival. The RA survivors required less late operative intervention (20%) as compared with other surgical patients (81%). A comparison of serial growth percentiles of CF patients with MI with those of their non-MI CF peers showed similar long-term decreases. These data confirm: (1) There is an improved survival for MI independent of the surgical procedure; (2) The BK ileostomy is an effective and time-tested MI treatment; (3) Primary resection and anastomosis in selected cases may have a lower surgical morbidity rate; and (4) Meconium ileus does not adversely affect the long-term nutritional outcome of CF patients. 相似文献
20.
A Fleming M Bishop W Shoemaker P Appel W Sufficool A Kuvhenguwha F Kennedy C J Wo 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(10):1175-9; discussion 1179-81
We prospectively tested the effect of the early postinjury attainment of supranormal values of cardiac index (> or = 4.52 L/min per square meter), oxygen delivery (> or = 670 mL/min per square meter), and oxygen consumption (> or = 166 mL/min per square meter) on outcome in traumatized patients with an estimated blood loss of 2000 mL or more. The goals in control patients were to attain normal values for all hemodynamic measurements. During the 6-month period, 33 protocol patients and 34 control patients with similar vital signs, estimated blood losses, and severity of injuries were enrolled in the study. Eight (24%) protocol patients died, while 15 (44%) control patients died. The protocol patients had fewer mean (+/- SEM) organ failures per patient (0.76 +/- 1.21 vs 1.59 +/- 1.60), shorter stays in the intensive care unit (5 +/- 3 vs 12 +/- 12), and fewer mean days requiring ventilation (4 +/- 3 vs 11 +/- 10) than did the control patients (P < .05 for each). We conclude that attaining supranormal circulatory values improves survival and decreases morbidity in the severely traumatized patient. 相似文献