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51.
BACKGROUND: The present study was performed to assess the value of ambulatoryblood pressure monitoring (ABPM) in determining the adequacyof blood pressure (BP) control, and its relationship to echocardiographicfindings in haemodialysis (HD) patients. METHODS: We studied 40 non-diabetic adult patients who had been on regularHD treatment for a median duration of 43 months. Twenty-four-hourABPM was performed using a non-invasive ABP monitor (Pressurescan,ERKA). Casual BP (cBP) was defined as the average of two measurementsobtained at two HD sessions, one preceding and one followingthe ABP recordings, and was calculated for both the predialysisand postdialysis phases. Two-dimensional and M-mode echocardiographywere performed in each patient to determine interventricularseptal thickness (IVS), left ventricular posterior wall thickness(LVPW), left ventricular fractional shortening (FS), and leftventricular mass index (LVMI) RESULTS: According to average 24-h BP levels, 50% of the patients hadsystolic hypertension (HT) (>139 mmHg), and 72.5% had diastolicHT (>87 mmHg), while only 25% had been diagnosed as HT bycBP measurements (P>0.01 and P>0.0001 respectively). Diurnalvariation in BP was not present in about 80% of the patients.Echocardiography was normal in only four patients (10%). LVMIand LV wall thickness were correlated to ABPM data better thanto cBP measurements. Using stepwise linear regression analysis,LVMI and FVS were positively correlated with systolic BP load(P> 0.0001 and P=0.0001 respectively), and LVPW was positivelycorrelated with night-time systolic BP level (P>0.001). CONCLUSIONS: ABPM is necessary to assess the adequacy of BP control, andis well correlated to end-organ damage of HT in HD patients.  相似文献   
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Although surveys have documented the ignorance of American teenagers on sexual matters, and other data suggest that a substantial segment of the public favors a sex education program in the schools, implementation has been limited. A questionnaire designed to test the feelings of public school teachers, students and community members was undertaken in a stable, conservative town of 1000 in Ohio. Respondents were asked to indicate which of 17 sex education topics should be included in a curriculum, the appropriate grade level for each, and whether each should be required or elective. They also ranked potential types of instructors, indicated interest in adult sex education, and rated desirability of student-parent and coeducational classes. The 1st choice for teacher type was a "sex education specialist," followed by a physician. Slightly over 1/2 of teachers favored parent-child sex education classes, but fewer than 25% of students did. Almost 2/3 of students favored coed classrooms for sex education, while 47.5% of teachers, about 1/3 of parents of school-age children, and fewer than 1/4 of persons without school-age children saw this as desirable. Teachers were most in favor of adult sex education (83.8%), and nearly 2/3 of all adults responded positively. A majority of all respondents favored including all 17 topics listed in a curriculum, but modal percentages of parents and persons without school-age children favored dropping masturbation and abortion from the sex education classroom, and homosexuality and premarital sexual relationships also met substantial opposition. Most groups agreed that with few exceptions sex education topics were most appropriate for grades 7-9. Although an expected strong resistence to sex education was not found, cautious administrators can find a number of reasons to avoid implementing sex education.  相似文献   
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Nonsteroidal antiinflammatory drugs (NSAIDs) such as aspirin, ibuprofen, and indomethacin, which inhibit prostaglandin (PG) synthesis, have a pronounced effect on a broad range of ethanol (EtOH) actions. Given this, it is somewhat surprising that NSAID treatment has not been found to alter major signs of ethanol withdrawal. To date, the only effect found has been indirect, that is, NSAID treatment reduces the efficacy of PG precursor administration in the treatment of ethanol withdrawal via the inhibition of PG formation. However, in those studies reporting negative results NSAID administration was delayed until EtOH withdrawal. Studies demonstrating NSAID-related attenuation of other actions of EtOH have typically employed a pretreatment paradigm in which NSAIDs are administered prior to, not after, ethanol exposure. Thus, it may be that the point in the ethanol exposure/withdrawal episode at which NSAIDs are administered could be crucial in determining their effects of the ethanol withdrawal syndrome. To address this issue, we employed a multiple-exposure "binge drinking" model. On each of 6 treatment days, male BALB/c mice were injected subcutaneously with either acetylsalicylic acid (ASA, 150 mg/kg) or the buffer vehicle, followed 1 h later by either ethanol (4.0 g/kg) or saline (0.9%) by gavage. Ethanol withdrawal severity, as measured by handling-induced convulsions, was determined 2, 4, 6, 8, 10, 12, and 24 h after EtOH gavage. ASA pretreatment was found to significantly reduce handling-induced convulsions in ethanol-intubated animals. In fact, the attenuation was of such a magnitude that the ASA-pretreated ethanol group did not significantly differ in withdrawal severity from non-ethanol-exposed controls. This effect was not likely due to ASA-related alterations in ethanol pharmacokinetics. These findings have relevance for the understanding of the basic mechanisms underlying ethanol dependence, as well as the potential role of PGs in this phenomenon.  相似文献   
54.
The present study examined possible parallels between the structure of human visuospatial abilities and the organization of the neural systems. Forty-eight participants were tested on seven speeded visuospatial tasks. Three of these tasks were constructed so as to rely primarily on known ventral stream functions and four were constructed so as to rely primarily on known dorsal stream functions. Both sets of tasks spanned approximately the same range of difficulty as indexed by both the speed and accuracy of decision making. Factor analysis of response times on the seven tasks revealed only two significant factors. The putative ventral stream tasks all loaded heavily on one factor (mean loading=0.843) but only weakly on the other factor (mean loading=0.222); the putative dorsal stream tasks showed the opposite pattern in that they all loaded heavily on the second factor (mean loading=0.828) but only weakly on the first factor (mean loading=0.229). These findings are consistent with the hypothesis that human visuospatial abilities can be classified using categories based on the specializations of underlying neural structures and systems.  相似文献   
55.
Contact biocides are a relatively new form of infection-resistant materials. Surfacine is a silver based antimicrobial coating that can be immobilized on the surface of most alloplastic materials used to fabricate devices. It exhibits broad-spectrum antimicrobial activity exclusively at the surface without elution and does not induce antimicrobial activity in contacting fluids such as urine regardless of volume. Because it is permanently immobilized on the material surface, the coating is nontoxic to cells and is not anticipated to exhibit immunogenicity, teratogenicity, or carcinogenicity.  相似文献   
56.
Eight-year event-free survival (EFS) was evaluated in 205 patients with acute lymphoblastic leukemia (ALL), to consider the efficacy of high-dose methylprednisolone (HDMP) given during remission induction chemotherapy between 1 and 29 days. The St Jude Total XI Study protocol was used after some minor modifications in this trial. Patients were randomized into two groups. Group A (n = 108) received conventional dose (60 mg/m(2)/day orally) prednisolone and group B (n = 97) received HDMP (Prednol-L, 900-600 mg/m(2) orally) during remission induction chemotherapy. Complete remission was obtained in 95% of the 205 patients who were followed-up for 11 years; median follow-up was 72 months (range 60-129) and 8-year EFS rate was 60% overall (53% in group A, 66% in group B). The EFS rate of group B was significantly higher than of group A (P = 0.05). The 8-year EFS rate of groups A and B in the high-risk groups was 39% vs 63% (P = 0.002). When we compared 8-year EFS rate in groups A and B in the high-risk subgroup for both ages together /=10 years, it was 44% vs 74%, respectively. Among patients in the high-risk subgroup with a WBC count >/=50 x 10(9)/l, the 8-year EFS was 38% in group A vs58% in group B. During the 11-year follow-up period, a total of 64 relapses occurred in 205 patients. In group A relapses were higher (39%) than in group B (23%) (P = 0.05). These results suggest that HDMP during remission-induction chemotherapy improves the EFS rate significantly for high-risk patients in terms of the chances of cure.  相似文献   
57.
A retrospective analysis was performed of 50 patients with adenoid cystic carcinoma who were seen in the Department of Radiation Oncology, University of Witwatersrand, Johannesburg, South Africa, in the past 10 years. There were 25 men and 25 women with a mean age of 52 years (age range, 21 to 88 years). Five patients had metastatic disease, and 17 had neural invasion. Thirty-four patients had surgery (11, complete; 23, microscopic residual). Sixteen patients had radiotherapy as initial management. The disease-free survival was 26%, overall survival was 29%, and local control was 30% at 10 years. Most recurrences occurred in the first 3 years. Nine patients had metastasis following treatment. The mean survival after metastasis was 15 months. Seven prognostic variables were analyzed using the log-rank test. There was no impact of age, site, type of salivary gland (major vs. minor), tumor stage, node positivity, or neural invasion on disease-free survival, overall survival, or local control. Extent of surgical resection (complete vs. microscopic residual) had a significant impact on disease-free survival and local control (P < 0.05) but no impact on overall survival (P > 0.05) because of the slow-growing nature of these tumors. Similarly, patients who had microscopic residual after surgery and were treated with radiotherapy did better than those who had biopsy and radiotherapy, although this was not significant statistically (P > 0.05). Thus, whenever possible, every attempt must be made to remove all microscopic tumor by surgery. Addition of postoperative radiotherapy with high-energy photons did not improve the locoregional control or survival in our series. There is a place for neutrons in the treatment of adenoid cystic carcinomas in advanced cases of inoperable or recurrent tumors, as a review of literature shows.  相似文献   
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