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101.
With estimates as high as 1.8 million individuals infected with human immunodeficiency virus (HIV) in the United States, the majority asymptomatic, it is crucial that all physicians routinely use adequate disinfection procedures for medical instruments. The protosigmoidoscopic disinfection procedures used by US family physicians were evaluated for adequacy in inactivating HIV. Sixty-seven percent of 1,585 randomly selected American Academy of Family Physicians members completed a mail survey regarding these procedures. Comparing procedures used with those recommended by the Centers for Disease Control or documented to inactivate HIV, 32.4 percent were judged to be appropriate procedures; 54.4 percent of the procedures were not tested or recommended; and 13.2 percent used appropriate solutions but at inadequate concentrations or exposure times. Therefore, a substantial proportion of US family physicians performing endoscopic procedures use disinfection procedures that may not inactivate HIV. The ever-increasing prevalence of HIV demands that standardized adequate disinfection procedures be implemented by all physicians to prevent the potential nosocomial spread of HIV. 相似文献
102.
Robert C. Flanigan Joseph H. Saiers Michael Wolf Eric H. Kraut Anthony Y. Smith Brent Blumenstein E. David Crawford 《Investigational new drugs》1994,12(2):147-149
Summary The Southwest Oncology Group (SWOG) studied the response rate and toxicity of merbarone (1,000 mg/m2 IV continuous infusion days 1–5, q 21 days) in patients with advanced metastatic renal cell carcinoma. Among 36 eligible patients, there was one partial response for a response rate of 3% (95% C.I. 0.1–15%). There were no mixed responses. There were no treatment related deaths or adverse drug reactions. Significant anemia, diarrhea, and hypercalcemia were observed. Mild to moderate degrees of malaise/fatigue/lethargy, dizziness/vertigo, hyperglycemia, creatinine increase, nausea, vomiting, weight loss, pedal edema, dyspnea, and granulocytopenia were noted. Merbarone does not have significant activity as a single agent in advanced renal cell carcinoma. 相似文献
103.
Abolition of flow-dependent EDRF release before that evoked by agonists in hypercholesterolaemic rabbits.
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1. We have used a pulsatile cascade bioassay system to investigate the effects of dietary-induced hypercholesterolaemia on EDRF release evoked by acetylcholine and by the oscillatory and time-averaged components of flow, in isolated segments of rabbit abdominal aorta. 2. Flow pulsatility (frequency range 0.1-10 Hz) was studied with constant flow (9 ml min-1) at a pulse pressure amplitude of 2 mmHg. Frequency-related EDRF release, maximal at 6 Hz, was slightly attenuated after 4 weeks and abolished after 8 weeks of cholesterol feeding. 3. Time-averaged shear stress was manipulated with dextran (1-4% w/v, 80000 mol. wt.), to increase perfusate viscosity. EDRF release induced by increased perfusate viscosity was unaffected after 4 weeks but abolished after 8 weeks of cholesterol feeding. 4. Endothelium-dependent relaxations to acetylcholine (0.1-10 microM) were not influenced after 4 weeks and only partially attenuated (by 60% of the maximal response, EC50 unchanged at 6.45 +/- 0.04 vs. 6.4 +/- 0.1 microM) after 8 weeks of cholesterol feeding. 5. Blood cholesterol levels were significantly (P < 0.001) increased after 4 weeks (26 +/- 3.6 vs 2.6 +/- 0.6 mmol l-1) and 8 weeks (56.2 +/- 3.8 vs 1.3 +/- 0.1 mmol l-1) of cholesterol feeding but after 8 weeks plasma L-arginine levels were not significantly different from the age-matched controls (0.2 +/- 0.05 vs. 0.19 +/- 0.04 mmol l-1). 6. We conclude that hypercholesterolaemia impairs flow-related (pulsatile- and time-averaged shear-induced) EDRF release earlier than acetylcholine-induced relaxation in rabbit aorta.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
104.
M Burch L Lum M Elliott N Carter D Slater A Smith A Ationu 《British heart journal》1992,68(3):309-312
OBJECTIVE--To determine the changes in the endocrine mechanisms of fluid balance after cardiopulmonary bypass in children. DESIGN--Prospective study; analysis of numbered plasma samples performed blind with respect to clinical data. SETTING--Regional paediatric cardiothoracic unit. PATIENTS--Nine patients, median age 4, range 2 to 9 years, five males. Patients under the age of 1 year were excluded because of the frequent blood sampling involved. MAIN OUTCOME MEASURES--Plasma concentrations of atrial natriuretic peptide (ANP), arginine vasopressin, plasma renin activity, aldosterone, noradrenaline and adrenaline, and urinary concentrations of cyclic guanosine monophosphate (cGMP) as measured by radioimmunoassay. RESULTS--After 30 minutes of cardiopulmonary bypass plasma atrial natriuretic peptide (ANP) decreased from (mean (SEM)) 151 (71) pg/ml to 52 (44) pg/ml (NS), and urinary production of its second messenger cyclic guanosine monophosphate (cGMP) decreased from 1286 (600) pmol/ml to 151 (414) pmol (p < 0.05). Other plasma concentrations of hormones studied did not change significantly although arginine vasopressin, adrenaline, and noradrenaline increased whereas aldosterone and plasma renin activity decreased. After cardiopulmonary bypass stopped there was an immediate and significant rise in plasma ANP, but within the next 24 hours plasma ANP declined significantly (p < 0.05), decreasing from 294 (49) pg/ml to 64 (29) pg/ml at 22 hours. In the postoperative period there was a significant correlation between plasma ANP and both mean fluid balance (r = 0.96, p < 0.001) and mean urine output (r = 0.97, p < 0.001). Plasma aldosterone peaked (p < 0.05) at 22 hours after operation, and argine vasopressin peaked (p < 0.05) at two hours and then declined (p < 0.05) to a trough at 24 hours. Plasma renin activity, adrenaline, noradrenaline, and urinary cGMP concentrations, and mean central venous pressure did not change significantly in the postoperative period. CONCLUSION--The changes documented show the differing pattern of release of water balance hormones invoked by cardiopulmonary bypass. The central role of ANP is shown by its strong correlation with urinary output and its similarly strong relation to fluid balance. 相似文献
105.
106.
A Thalamic Contribution to Arousal-induced, Non-photic Entrainment of the Circadian Clock of the Syrian Hamster 总被引:3,自引:0,他引:3
Elizabeth S. Maywood Emma Smith Stephanie J. Hall Michael H. Hastings 《The European journal of neuroscience》1997,9(8):1739-1747
It is well established that the circadian clock of the suprachiasmatic nuclei (SCN) is entrained by light. More recently, the potent effects of arousing, non-photic cues on the clock have been recognized. The neural mediators of non-photic entrainment are yet to be identified. To examine the contribution of the thalamic intergeniculate leaflet (IGL) and its NPY-immunopositive projection, the geniculo-hypothalamic tract to non-photic entrainment by arousal, male Syrian hamsters received lesions of the IGL (IGLX) which ablated NPY-immunoreactivity in the SCN. Their circadian responses to both photic and non-photic cues were then tested. Lesions resulted in a delay in the timing of activity onset following lights out, but had no effect on the behavioural or cellular circadian responses to phase-advancing light pulses presented at circadian time (CT) CT19 (where CT12 represents the time of activity onset). Injection with a benzodiazepine (chlordiazepoxide, 100 mg/kg) at CT6 suppressed wheel-running, increased general locomotion of intact controls and induced large phase advances of the circadian rhythm of wheel-running. Chlordiazepoxide also inhibited wheel-running in lesioned animals, but there was no significant increase in general locomotion and the lesioned animals did not phase advance. Serial arousal by injection of saline at intervals of 23.5 h for 6 days entrained the circadian rhythm of wheel-running of intact hamsters and was associated with an increase in general locomotor activity. Entrainment by serial arousal was abolished by IGLX. However, the lesioned animals did show a clear behavioural response to every presentation of the non-photic cue. These results show that the IGL is a necessary component of the neural pathways mediating both arousal- and benzodiazepine-induced non-photic entrainment. 相似文献
107.
108.
Health education professional preparation programs were surveyed to determine the extent of HIV/AIDS education health educators are receiving. The survey also addressed content areas, skills being developed or enhanced, areas of deficiency in preparation programs, and areas in which national professional associations may assist in the preparation of AIDS educators. One hundred eight-three surveys were mailed; 114 (68%) were completed and returned. Twenty-one institutions reported planning a separate course on HIV/AIDS. Most were designing general service courses to reach a broad cross-section of students. Twenty-five institutions (23.8%) reported previously offering or currently offering a specific course on AIDS. One hundred two (89.5%) respondents reported HIV/AIDS warranted the attention and funding it had received. Thirty-seven (35.2%) respondents reported AIDS education was of sufficient importance to influence hiring of faculty members in their departments. Survey findings demonstrate that current AIDS education courses targeted to the general student population may not be adequate in meeting the professional preparation needs of health educators charged to provide AIDS education. 相似文献
109.
L H Hollier F I Smith J C Rice C H Kliger M D Kerstein 《American journal of surgery》1990,160(2):179-181
This investigation was designed to study the effects of home health care (HHC) on patients who have been hospitalized with peripheral vascular disease. For a patient to have HHC, the patient had to have a defined wound, educational needs, or both. Sixty patients, 30 with HHC and 30 without, were contacted approximately 30 days after their last hospital discharge. The 30 patients with HHC were deemed to be at increased risk because of multisystem disease with multiple medications, infirmity, early senility, and often complex wounds. In a prospective fashion, each patient was interviewed by either a registered nurse or medical student using a standardized data collection form. The following issues were assessed: incidence of postoperative complications, knowledge of the patient of his or her disease, compliance with medication (knowledge of, regular use), incidence of readmission, and unscheduled clinic or emergency department visits. Upon statistical analysis using the two-sample t-test and Pearson chi-square test, no significant differences were found between the two groups in terms of complications, compliance, or patient education. HHC, therefore, was found to be helpful to patients with peripheral vascular disease. In our study, the use of HHC made the risk of complications in a group of patients with defined teaching needs and wound care needs equal to that in a group with no such defined needs on discharge from the hospital. 相似文献
110.
Advanced transcranial lesions may be successfully resected through a variety of contemporary skull base approaches. The identification and isolation of the internal carotid artery throughout its petrous course is essential in most of these surgical techniques. Anatomic landmarks normally used to identify this vital structure, however, may be severely distorted by tumor involvement or previous operative dissection. In an effort to define surgical landmarks that may be used in the identification of the petrous carotid artery, histologic sections of 100 temporal bones from adults were examined and microscopic measurements were recorded from the anatomic dissection of 10 fresh cadaver halfheads. On the basis of these studies, structures we have found useful in identification of the vertical petrous carotid artery during lateral skull base approaches include the: base of the styloid process, bony vascular crest, basal turn of the cochlea, medial wall of the eustachian tube, and the cochleariform process. Identification of the horizontal segment can be achieved by the preliminary delineation of the middle meningeal artery, greater petrosal nerve, tensor tympani muscle, mandibular and maxillary divisions of the trigeminal nerve, and the eustachian tube. Specific anatomic relationships with associated measurements are detailed and correlated with selected, illustrative cases. 相似文献