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111.
Andrea S. Lowe G. David Baxter Deirdre M. Walsh James M. Allen 《Lasers in medical science》1995,10(4):253-259
The effects of low-intensity near-infra-red laser irradiation (820 nm; 1.5 and 9.0 J cm–2; pulsed at 12 Hz, 73 Hz and 5 kHz) upon peripheral neurophysiology and skin temperature were investigated using antidromic conduction studies in the human median nerve in vivo. Healthy human volunteers (n = 90) were recruited and allocated randomly to either a control group (n=10) or one of eight experimental groups (two radiant exposures, 1.5 J cm–2 and 9.0 J cm–2 at one of three pulse repetition rates, 12 Hz, 73 Hz or 5 kHz, in addition to a placebo group for each radiant exposure;n = 10 all groups). Analysis of variance (ANOVA) demonstrated a significant (p0.05) decrease in skin temperature following irradiation at the lowest radiant exposure (1.5 J cm–2) combined with pulse repetition rates of 73 Hz and 5 kHz, with the greatest effect at 73 Hz. These changes in skin temperature were coupled with increases in negative peak latency (NPL); ie changes in NPL were inversely related to changes in skin temperature. However, in contrast to the authors' previous findings using continuous wave (CW) laser irradiation, differences in NPL were not found to be significant. These findings, therefore, provide little evidence of the neuro-physiological effects of low-intensity infra-red irradiation at the dosage levels and pulse repetition rates used here. 相似文献
112.
This paper addresses the role of information in health policy reform. It recognizes that reform can be based on data, but that there are other influences on health policy. The steps involved in making policy, including problem identification, comparison of solutions, policy adoption, implementation, and amendment, all require information. When information is unavailable for any of these steps, the policy process sometimes proceeds without it. The policy makers must make difficult choices regarding the potential benefit of comprehensive information to the policy outcome versus the potential drawbacks, in terms of time and cost, of seeking the missing information. Different areas where data are needed within health policy are enumerated, as are sources of health policy data, and examples of strategies are given. Finally, three case studies are presented, highlighting the use of information in policy making. The National Epidemiology Board in Thailand commissioned studies by experts on relevant policy topics. It had a substantial impact on changing policies in the areas of AIDS control, iodine deficiency, essential drugs and vaccination. The attempt at decentralizing health administration to the province level in Papua New Guinea is the second example presented. At the time of the evaluation, this effort had not yet attained its objectives of improving the health of the people, nor had it reduced costs or lessened inequity among regions. If this reform had been tested in a pilot project, its problems may have been discovered at an earlier stage of implementation when they would have been easier to correct. The final case concerns the UNICEF child survival interventions during the 1980s. These interventions were chosen based on cost-effectiveness analysis and were successfully implemented. The use of cost-effectiveness analysis in prioritizing interventions is one example of the way in which information can improve policy and health outcomes. 相似文献
113.
To make an informed decision when choosing a contraceptive, women and couples need to know how effective different methods are when used perfectly, where perfect use is defined as following the directions for use. In this article, we show that unbiased estimates of pregnancy rates during perfect use can be guaranteed only if information on consistency and correctness of use is available for each menstrual cycle. The estimated probability of pregnancy during a year of perfect use among the subset of women who always used a method perfectly will be biased upward. 相似文献
114.
CONTEXT: Condoms made of latex are not comfortable or appropriate for all consumers. Polyurethane condoms may provide a needed alternative. METHODS: In a double-masked study, 805 monogamous couples were randomized to use either the polyurethane condom or the latex condom for six months. Couples recorded the frequency of intercourse, of condom use and of breakage and slippage throughout the trial in coital diaries and in detailed reports on the first five uses. Breakage and slippage rates were determined, and typical-use and consistent-use pregnancy rates were calculated using life-table analysis, adjusted for use of emergency contraception. RESULTS: The six-month pregnancy rate during typical use (adjusted for use of emergency contraception) was 4.8% for the polyurethane condom and 6.3% for the latex condom. Similarly adjusted pregnancy rates during consistent use over six completed menstrual cycles--2.4% for the polyurethane condom and 1.1% for the latex condom--did not differ significantly. Clinical failure rates (including breakage and slippage occurring during either intercourse or withdrawal) were 8.5% for the polyurethane condom and 1.6% for the latex condom. In general, male participants were more satisfied with the latex condom, and users of latex were significantly less likely to drop out of the study for condom-related reasons than were users of polyurethane. CONCLUSIONS: Although polyurethane and latex condoms provide equivalent levels of contraceptive protection, the polyurethane condom's higher frequency of breakage and slippage suggests that this condom may confer less protection from sexually transmitted infections than does the latex condom. 相似文献
115.
Walsh J 《Social work in health care》1999,30(1):31-49
Social workers in mental health settings frequently participate in the treatment of clients with incapacitating anxiety. Medication is often included among the interventions for these clients. Social workers, who specialize in psychosocial interventions, also have key roles in the assessment and monitoring of medication effects. The purpose of this article is to provide social workers with an overview of the pharmacological treatment of anxiety so that they can carry out their range of interventions more effectively. Included is information about types of medication and their dosages, positive and adverse effects, interactions of medication with other interventions, and special concerns with children and adolescents. 相似文献
116.
This study was designed to identify gender and age-related differences among complete denture referrals from general dental practice to a dental teaching hospital over a 4 year period. Referral rates were calculated according to male/female ratios in the edentulous population. Although more women than men were referred overall, the proportion of males to females referred was similar to that in the edentulous population. Significant gender-related differences in referral patterns were identified, suggesting that edentulous males with complete denture problems, and aged 69 or less, made proportionately less use of hospital services, and proportionately more when aged 70 or over. 相似文献
117.
Ancoli-Israel S Walsh JK Mangano RM Fujimori M 《Primary care companion to the Journal of clinical psychiatry》1999,1(4):114-120
BACKGROUND: Insomnia is a very common symptom, particularly in the elderly. Thus, all hypnotic medications should be carefully evaluated in the elderly population. Zaleplon, a new nonbenzodiazepine hypnotic with a short elimination half-life (approximately 1 hour), was evaluated in the current study. METHOD: This multicenter, randomized, placebo-controlled outpatient study evaluated the efficacy and safety of zaleplon, 5 and 10 mg, in elderly patients with insomnia (as defined by DSM-IV); zolpidem, 5 mg, was the active comparator. Sleep was assessed in 549 elderly patients (>/= 65 years old) by using morning questionnaires completed after each of 7 baseline nights during which placebo was given, 14 nights of double-blind treatment, and 7 nights of placebo after discontinuation of active treatment. RESULTS: Zaleplon, 10 mg, and zolpidem, 5 mg, significantly reduced sleep latency during both weeks of the study. Zaleplon, 5 mg, reduced sleep latency only during week 2. Sleep duration was increased with zolpidem, 5 mg, during weeks 1 and 2 and with zaleplon, 10 mg, during week 1. No clinically significant rebound insomnia was observed after discontinuation of treatment with zaleplon, whereas evidence of rebound effects was seen with zolpidem. There was no significant difference between either zaleplon dose and placebo in the frequency of any central nervous system adverse events. CONCLUSION: Zaleplon is effective in reducing latency to sleep without evidence of undesired effects in elderly patients with insomnia. 相似文献
118.
A prospective comparative study of MR sialography and conventional sialography of salivary duct disease 总被引:7,自引:0,他引:7
Varghese JC Thornton F Lucey BC Walsh M Farrell MA Lee MJ 《AJR. American journal of roentgenology》1999,173(6):1497-1503
OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of MR sialography in the examination of patients with salivary duct disease. SUBJECTS AND METHODS: Forty-nine patients (23 males and 26 females; 16-78 years old; mean age, 47 years) with symptoms related to the salivary glands underwent both conventional sialography and MR sialography. The latter was performed using a heavily T2-weighted, two dimensional, fast spin-echo technique and a 12-cm circular surface coil. Contiguous 3-mm axial images with frequency-selective fat suppression were acquired through the symptomatic gland. The MR sialography findings were compared with the final diagnoses determined by conventional sialography. RESULTS: Conventional sialography showed calculus disease (n = 13), stricture (n = 12), sialectasis (n = 4), cast (n = 3), neoplasm (n = 2), and normal duct (n = 16). MR sialography alone had a sensitivity of 69% in revealing calculus disease. However, the sensitivity increased to 100% when MR sialograms were combined with control radiographs. MR sialography was sufficient to accurately reveal stricture, sialectasis, and neoplasm and to direct therapy on the basis of its findings. Overall, MR sialography combined with control radiographs had a sensitivity, specificity, and diagnostic accuracy of 100%, 88%, and 96%, respectively, in revealing salivary duct abnormalities. CONCLUSION: MR sialography alone is not sufficiently sensitive to reveal salivary duct stones. Caution must be exercised when excluding calculus disease. MR sialography, when combined with control radiographs, is accurate and has the potential to replace conventional sialography. 相似文献
119.
Infarction of omentum and epiploic appendage: Diagnosis, epidemiology and natural history 总被引:7,自引:0,他引:7
Epiploic appendagitis and segmental omentum infarction are considered to be rare conditions, which may mimic an abdominal
surgical emergency. The purpose of our study was to describe clinical findings, US and CT appearance of infarction of an epiploic
appendage and omentum, and to determine their epidemiological characteristics and natural history. We retrospectively studied
clinical, US and CT findings at hospital admission and follow-up of all patients who were diagnosed at our institution with
epiploic appendagitis or omentum infarction between June 1988 and November 1997. We found a relatively high incidence of 40
cases: 20 patients with epiploic appendagitis, 11 with omentum infarction, and 9 in whom it was not possible to discriminate
between the both. All 40 patients recovered under conservative treatment without complications. We conclude that US and CT
features allow a reliable diagnosis, thereby obviating unnecessary surgery. Discriminating between both conditions is of no
practical relevance since treatment and prognosis are identical.
Received: 30 November 1998; Revised: 30 March 1999; Accepted: 6 September 1999 相似文献
120.
Practical approaches to the initial evaluation of solid organ transplant patients, BMT patients, and HIV-infected patients with pulmonary disease are summarized in Figures 2, 3, and 4. These algorithms are meant to be used as guidelines for the clinician. The clinical setting will ultimately determine the extent and speed of the evaluation. Patients who are recipients of solid organ transplants and have pulmonary symptoms may have focal or diffuse changes or may have normal chest radiographs. In all these groups, sputum is obtained by expectation. If a pathogen is found in any of the groups, it is treated. When no pathogen is found on sputum examination in patients with focal disease, empiric antibiotic therapy is given. If the patients do not improve on the empiric antibiotics, then bronchoscopy is performed. Some centers proceed directly to bronchoscopy before antibiotics are started in the hope of directing antibiotic therapy. Patients who have a normal CXR or diffuse infiltrates and no identified pathogen on examination of sputum undergo bronchoscopy, and the protocol is followed until a diagnosis is made (see Fig. 2). Patients who have received a BMT and who present with pulmonary symptoms are treated as shown in Figure 3. The CXR will reveal if the infiltrate is focal or diffuse. Those with focal infiltrates are treated with broad-spectrum antibiotics for 48 to 72 hours. If the symptoms and signs do not show some resolution, then bronchoscopy is usually performed. The effect of diffuse infiltrates in BMT patients depends to a large extent how far along in recovery from the transplant the patient is when they develop the infiltrates. During the first 30 days posttransplant, pulmonary edema commonly occurs, and the infiltrates may resolve with diuresis. If the patient is not clinically fluid overloaded or they do not respond to the diuretic therapy, then bronchoscopy with BAL is indicated. Finally, many HIV-infected patients may present with pulmonary symptoms. They may have a normal CXR or a diffuse or focal pattern (Fig. 4). All patients are subjected to sputum induction to identify a pathogen. If one is identified, it is treated. Should the patient not respond to treatment adequately or a pulmonary pathogen is not found, then bronchoscopy with BAL, protected specimen brush, or a transbronchial biopsy is attempted. The above schema is a general guideline to the initial evaluation of pulmonary disorders in the ICP. The respiratory abnormality is found in most of the cases if these algorithms are closely followed. If the patient does not improve or deteriorates further, additional diagnostic procedures such as video-assisted thorascopic lung biopsy or CT-directed transthoracic needle biopsy may be needed. 相似文献