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971.
OBJECTIVE: To examine in women with systemic lupus erythematosus (SLE) who participated in a clinical trial the relationship between daily dose of dehydroepiandrosterone (DHEA), serum levels of DHEA and DHEA sulfate (DHEAS), clinical effectiveness, and side effects. METHODS: Twenty-three women with mild to moderate SLE were treated with DHEA for a 6 month period. The starting dose was 50 mg/day, and monthly stepwise increases were allowed. Subjects were assessed monthly by the Systemic Lupus Erythematosus Disease Activity Index, Systemic Lupus Activity Measure (SLAM), Health Assessment Questionnaire, and other outcomes. Serum testosterone, DHEA, and DHEAS levels were obtained and side effects noted monthly. RESULTS: Statistically significant improvements were found in all lupus outcomes over 6 months. Serum DHEA and DHEAS levels correlated with the dose of DHEA. Serum DHEA and DHEAS correlated negatively with SLAM score. A second order regression analysis of serum DHEAS level versus SLAM score suggested that the optimal serum level of DHEAS was 1000 microg/dl. The most common side effect was acne. CONCLUSION: The clinical response to DHEA was not clearly dose dependent. Serum levels of DHEA and DHEAS correlated only weakly with lupus outcomes, but suggested an optimum serum DHEAS of 1000 microg/dl. Monitoring these serum levels appears to have limited clinical utility.  相似文献   
972.
We conducted a comparative evaluation of the Chlamydiazyme (Abbott Laboratories), PACE 2 (Gen-Probe), and AMP-CT (Gen-Probe) assays for the detection of Chlamydia trachomatis in endocervical samples. Specimens from 787 females were included in the study. The sensitivities of the PACE 2 and Chlamydiazyme assays in comparison to the results of the AMP-CT assay were 79.3 and 63.4%, respectively. The specificities of the Chlamydiazyme and PACE 2 assays were 100%. All of the positive specimens detected in this study were positive by the AMP-CT assay. On the basis of the final results of the comparison, the prevalence of C. trachomatis in the population was 10.4%. Retesting of specimens whose results were in the intermediate zone by the PACE 2 assay by a probe competition assay identified some additional true-positive specimens. Amplification assay testing of such specimens did not significantly increase the yield. The majority of specimens which tested positive by the AMP-CT assay only were not in the intermediate zone by the PACE 2 assay. We were unable to identify demographic or clinical factors which could predict those individuals who tested positive by amplified tests but not by nonamplified tests. The Gen-Probe PACE 2 assay proved to be superior to the Chlamydiazyme assay for the screening and diagnosis of C. trachomatis infections in female endocervical specimens.  相似文献   
973.
Treatments for diabetes in Ethiopia are at present only available in hospitals so many patients must travel great distances to obtain insulin, tablets, and diabetes education. We reviewed all 496 people with diabetes attending the diabetic clinic at Gondar Hospital (281 with Type 1 (insulin-dependent) diabetes mellitus (DM) and 215 with Type 2 (non-insulin-dependent) DM. Half of the patients came from rural areas, all but 3 of them travelling more than 20 km, one-quarter of them more than 100 km and 33 patients (13%) more than 180 km. It is likely that many patients who fail to attend from the more distant areas have died. We are developing a scheme which would enable diabetic patients to be treated at rural health centres by nurses trained in the principles of diabetes care which could greatly improve the outlook for diabetic patients in Ethiopia.  相似文献   
974.
Computed tomography remains the imaging modality of choice in the detection of two processes: acute intracranial hemorrhage and calcification; however, in the subacute and chronic stages of hemorrhage, MR imaging is more sensitive in aging and staging hemorrhage. FLAIR imaging increases the sensitivity of MR imaging in the detection of subarachnoid hemorrhage. The signal characteristics of calcification on MR imaging is variable, especially on T1-weighted images decreasing its detectability. CT is superior to MR imaging in the detection of calcification. A number of factors including slice thickness, as well as window width and level may affect the detectability of calcification on CT.  相似文献   
975.
The percutaneous Hemopump showed beneficial effects during coronary angioplasty in 32 high-risk patients with unloading of the left ventricle during ischemia and maintaining cardiac output with mean aortic pressures of 50 mm Hg in case of cardiac arrest (3 patients). High procedure-related morbidity (occlusion of femoral artery in 2 patients; bleeding with need of transfusion in 4 patients) and mortality (4 of 32 patients) rates demonstrate the need for a very careful selection of patients.  相似文献   
976.
OBJECTIVE: To assess relations of left ventricular (LV) geometry and function to insulin resistance in obesity-a condition associated with volume overload and abnormal LV relaxation. DESIGN: Cross-sectional relational study. SUBJECTS: 27 healthy overweight-obese subjects (18 women, body mass index (BMI) = 35.0+/-4.0 kg/m2) and 31 age-matched normal-weight controls (21 women, BMI = 22.6+/-2.4 kg/m2). MEASUREMENTS: Subjects were studied by Doppler-echocardiography the same day and hour (08.00 h) as measurements of fasting insulin and blood glucose were made. Insulin resistance was determined by the 'Homeostasis Assessment Model'. RESULTS: Twelve obese subjects with insulin resistance (IR) had higher body size than 15 patients without IR and higher blood pressure than normal-weight controls (all P < 0.01). Relative IR was related to isovolumic relaxation time. This relation was not maintained after controlling for age, blood pressure, weight and height. Isovolumic relaxation time was, however, positively related to diastolic blood pressure, a measure of load, in normal controls (r=0.44) and obese without IR (r=0.62) but not in insulin resistant subjects (r=0.14). CONCLUSION: IR does not independently influence myocardial relaxation in uncomplicated obesity, but modulates the effect of load on active diastole.  相似文献   
977.
This paper aims to explore the meaning of spirituality in relation to nursing care using concept synthesis. Walker and Avant give three ways in which concept synthesis can occur: discovering new dimensions to old concepts, searching for similarities and discrepancies among sets of related concepts, and observing previously undescribed phenomena. It is the first two of these methods which have been used here. The phenomena that emerged from a reading of the literature around spirituality were meaning, presencing, empathy/compassion, giving hope, love, religion/transcendence, touch and healing. These phenomena were studied in order to sort them into fewer categories. They all appeared to be products of a relationship, some physical (presencing, touch and healing), and others emotional (meaning, empathy/compassion, hope, love, and religion/transcendence). Some of the phenomena appeared to fit in both categories, especially healing, which could be of a physical or emotional/spiritual nature. Once the two main categories had been arranged, it was obvious that a split between psyche and soma was not appropriate for labelling the spiritual dimensions of nursing care, as the original definition of spirit was something which motivated the body. Spiritual care is inseparable from physical, social and psychological care because together they form the whole (Bradshaw 1994 p. 282). The two categories were then collapsed into one and given the label 'connection'.  相似文献   
978.
We examined the effects from subjects, technicians and spirometers on within-session variability in successful recordings of forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in 4989 asymptomatic never-smoking men. All eligible men aged 30-46 years living in western Norway (n = 45,380) were invited to a cross-sectional community survey. Information on respiratory symptoms, smoking habits and occupational exposures was obtained from a self-administered questionnaire. Three successful FEV1 and FVC recordings were obtained in 26,368 attendants using three dry-wedge bellow spirometers operated by 10 different technicians. Within-subject standard deviation (SD) from three recordings of FEV1 and FVC was on average 102 and 106 ml, respectively, and increased with height (14 and 17 ml, respectively, per 10 cm) and body mass index (BMI) (11 and 14 ml, respectively, per 5 kg m-2). Between-subject SD of the mean of three FEV1 and FVC recordings was 591 and 754 ml, respectively, and increased in groups of increasing height (43 and 40 ml, respectively, per 10 cm). Small, but significant, differences were observed between technicians in within-subject SD and in levels of FEV1 and FVC. Homogeneity of between-subject variability, necessary for linear regression analysis, was obtained using FEV1 and FVC divided by height squared. In conclusion, within-subject variability in three successful spirometric recordings was small, but dependent on height and BMI of the subjects as well as technician performance. The observed heterogeneity in between-subject variation in FEV1 and FVC levels disappeared when each variable was divided by height squared. Novel multiple linear regression equations for FEV1/height2 and FVC/height2 were developed to be used in evaluating the effects from occupational airborne exposures in Nordic men aged 30-46 years.  相似文献   
979.
The human neurotropic papovavirus JC, a close relative of simian virus 40, has been associated with the formation of brain tumors in humans because of its ability to induce such tumors in other primates under experimental conditions. Here we have analyzed 30 brain tumors classified as either oligodendroglioma or astrocytoma and 22 cell lines derived from human gliomas for the presence of JC viral sequences using polymerase chain reaction with two different sets of primers. None of the tumors or cell lines contained JC viral sequences. Similarly, we failed to detect expression of JC T antigen in any of 26 human glioma lines analyzed in this study. We conclude that JC virus is not a major cause of human brain tumors.  相似文献   
980.
PURPOSE: To construct tissue-specific cDNA libraries containing copies of genes of ion transporting and receptor proteins in lens and cornea epithelia. To screen the libraries for the cDNA of these molecules and to deduce the protein sequence from the cDNA sequence. METHOD: Lens and corneal cDNA libraries are not commercially available and are difficult to prepare from microdissected single animal eyes or cadaver human eyes due to the small amount of tissue. To overcome these problems, we refined an approach for preparing high efficiency, non-PCR amplified plasmid cDNA libraries, where only nanogram quantities of poly (A) RNA are required. Plasmids were electrotransformed into DH10B bacteria and routinely yielded >10(6) independent colonies with typically >90% recombinants. Randomly selected colonies were subjected to colony PCR analysis to determine the libraries average insert size (typically approximately 1-kb). Primers to known genes were used in PCR amplification to check for representation of the genes in the cDNA libraries. RESULTS: Using libraries from rabbit cornea epithelium and endothelium, cultured human lens epithelium, and alphaTN4 cells, we have found the libraries to contain the cDNA for 3 common housekeeping proteins expected to be at high copy numbers in all cells. In addition, we identified 22 rare proteins and for many we determined the complete coding regions. These include K+ channels, Cl- channels, Ca++ channels, Na+ channels, three exchangers, the Na+-HCO3- cotransporter, and three kinds of receptors. CONCLUSION: Cornea and lens libraries have been constructed from single cornea or lens preparations. The libraries often contain the cDNA sequences for ion transporting and receptor proteins which are expected to be relatively rare in these cells. Many of these cDNA's have now been sequenced and the encoded proteins identified.  相似文献   
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