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991.
GM Brunier  J Graydon 《Canadian Metallurgical Quarterly》1993,20(4):457-61; discussion 462, 521
This study examined the relative influence of anemia, nonspecific symptoms and physical activity on fatigue in 43 patients with end stage renal disease on chronic hemodialysis. We found that low levels of physical activity and frequent symptoms were related to high levels of fatigue. Degree of anemia was not related to level of fatigue. Inactivity contributed to fatigue scores more than symptoms.  相似文献   
992.
The records from 34,819 obstetric epidurals performed at Birmingham Maternity Hospital over the period 1969-1988 were examined. During that time there were 460 dural taps (overall incidence 1.3%). Of the methods used to detect the epidural space, loss of resistance to injection of saline was associated with the lowest incidence of dural tap (0.6%). The incidence of typical postdural puncture headache when managed conservatively was 86%. Provision of an epidural drip after delivery reduced the incidence of headache to 70%. Elective forceps delivery conferred no additional benefit, and tended to delay the onset of headache. Blood patches were performed on 135 patients and provided complete relief of headache in 93 (68%). A further 23 patients (16%) obtained partial relief.  相似文献   
993.
994.
We report dual energy X-ray absorptiometry (DXA) studies of total body bone mineral and body composition performed in 111 normal caucasian women (aged 42-61). Conventional DXA scans of the lumbar spine and femoral neck were also obtained and each woman completed a detailed questionnaire. Significant correlations were found between total body BMD and BMD in the lumbar spine (r = 0.76) and femoral neck (r = 0.72). We present reference range data for BMD in the total body and in seven subregions of the skeleton. Multiple linear regressions of total body BMD and BMC on weight, height and age showed that the inclusion of height compared with weight and age alone was not statistically significant. The dependence of total body BMD on weight and age was: total body BMD (g cm-2) = 1.043 + 0.0042 x weight (kg) - 0.0039 x age (years) (R = 0.46, SEE = 0.074 g cm2). Body mass derived from DXA scans correlated well with weight measured on scales (r = 0.996, SEE = 0.77 kg). Body composition measurements agreed closely with % body fat estimated from skinfold measurements (r = 0.93), body fat mass estimated from a predictive equation based on weight, height and age (r = 0.91) and % body fat estimated from a predictive equation based on body mass index (r = 0.76). Study precision gave coefficients of variation of 0.6% for total body BMD and 0.7% for % body fat.  相似文献   
995.
142 adults with pharyngeal and laryngeal diphtheria were registered in Yekaterinburg in 1993. Of them, 136 patients recovered and 6 died. The analysis of the clinical features and diagnostic errors showed that subjects with chronic visceral diseases and alcoholics are more likely to have poor prognosis of diphtheria. Diphtheria manifested primarily with edema followed by infiltration of the mucosa, with appearance of thin transparent furs, tenderness of cervical regional lymph nodes. The typical greyish-brown thick and firm false membranes occurred only in the late stage of the disease. The features of the diphtheric croup in the adults complicated the diagnosis. These were, unlike croup in children, the vagueness of the stages of this syndrome, rapid involvement of the trachea and bronchi, mixed type of dispnea and delirious state in alcoholics. It is necessary to set up the duty of ENT specialists in the diagnostic departments of the infectious hospitals for repeated endoscopic and bacteriologic examinations of the diphtheria suspects.  相似文献   
996.
Because of the complexity of their illness, patients infected with HIV may require many services to facilitate the management of the disease. The primary care provider must understand and facilitate the services that are needed and needs to be familiar with the individuals responsible for the care of each patient. There are many stresses that have been identified in HIV caregiving, for informal caregivers and health care workers. These stresses are described, and suggestions for appropriate interventions are outlined.  相似文献   
997.
We report eight patients with metastatic malignancy who developed severe back and leg pain caused by ischiogluteal bursitis. Careful evaluation excluded the possibility of bony metastases. Ischiogluteal bursitis is an easily diagnosed condition that can be effectively treated with local injection of corticosteroids. Recognition of this disorder will allow prompt therapy and unnecessary evaluation expenses.  相似文献   
998.
Rigorous analysis of multiple coupled rib waveguides   总被引:1,自引:0,他引:1  
The general problem of multiple coupled rib waveguides, where energy may be leaked from one guide to the other via the substrate and radiation mode, is treated. Rigorous results including substrate and air modes coupling are sought for the general case of coupling of two or more different guides. The analysis, developed in terms of a cascade of the transverse steps, utilizing a variational solution with a single trial function and making explicit use of edge singularities at the dielectric corners in order to produce an effective and rigorous solution, is presented. Multiple coupled rib guides are then reduced to a cascade of interacting step discontinuities in the transverse direction. When comparison is possible, the numerical results obtained by the method are seen to be as accurate as those obtained by the finite element method (FEM)/finite difference method (FDM), but with a fraction of the computer time and memory involved  相似文献   
999.
Although nomograms to convert readings of resistance (R) and reactance (Xc) into estimates of body composition have begun to emerge for children as well as adults, there has been reluctance to use bioelectrical impedance analysis (BIA) in very young children due to the irritability of children, measurement instability, positioning of electrodes, and, of course, reproducibility of measurements. The precision of completely independent measurements of BIA indices was evaluated by two observers by comparing a series of 40 measurements of R and Xc and 36 measurements for weight in four malnourished children on 10 different days during the course of their nutritional recuperation. For weight, the CV (coefficient of variation) was 3.5% for observer A and 3.8% for observer B. There were no differences in the means across observers with respect to weight, R, and Xc. The results obtained in this study illustrate that properly trained observers following the same standards can produce equivalent data for BIA and weight measurements even in sick children.  相似文献   
1000.
Proteases play a crucial role in apoptosis or programmed cell death. The aim of this review is to highlight the purpose for which these proteases are activated, i.e., to specifically cleave a select subset of cellular proteins at an appropriate time during cell death. Poly(ADP-ribose) polymerase (PARP), a nuclear protein implicated in DNA repair, is one of the earliest proteins targeted for a specific cleavage to the signature 89-kDa fragment during apoptosis. Characterization of the apoptotic cleavage of PARP and other target proteins helped in understanding the role of cysteine aspartic acid specific proteases (caspases) in the apoptotic process. We have recently identified that in some models of cell death, the cleavage pattern for PARP is different from production of the signature 89-kDa fragment. Necrotic death of HL-60 cells and apoptotic death of Jurkat cells mediated by granzyme B and perforin were accompanied by distinct additional fragments, suggesting cleavage of PARP at other sites by caspases or other death proteases. This review summarizes how detection and characterization of PARP cleavage could serve as a sensitive parameter for identification of different types of cell death and as a marker for activation of different death proteases. The putative biological functions for early cleavage of PARP in apoptosis are also discussed.  相似文献   
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