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991.
The microbiology of in 55 ear aspirates obtained from 34 children with chronic otorrhea was studied. Aspiration of the middle ear exudate was done immediately following removal of tympanostomy tube (TT). The middle ear aspirates and swab specimens of the external auditory canals were cultured for aerobic and anaerobic bacteria. Sixty-five isolates were recovered only from the middle ears, 73 only from the external ear canals, and 73 were present at both sites. Analysis of the 138 middle ear isolates demonstrated the recovery of aerobic bacteria only in 28 patients (50%), anaerobes only in seven (13%), and both aerobes and anaerobes in 20 (36%). There were 77 aerobic and 61 anaerobic isolates. Commonly recovered aerobes were Pseudomonas aeruginosa (17 isolates), Staphylococcus aureus (11), Proteus sp. (7), Moraxella catarrhalis (6), Klebsiella pneumoniae (5) and non-typable Haemophilus influenzae (5). Commonly isolated anaerobes were Peptostreptococcus sp. (25 isolates), Prevotella sp. (10), Bacteroides sp. (8) and Fusobacterium sp. (6). Pseudomonas aeruginosa and S. aureus were more often isolated in children older then 6 years. These findings demonstrate the polymicrobial bacteriology of TT-related otorrhea in children. Specimens collected from the external auditory canals can be misleading. Reliable information can be obtained from the ear exudes when collected through the TT or through the open perforation after their removal.  相似文献   
992.
The human immunodeficiency virus type 1 transmembrane protein gp41 oligomer anchors the attachment protein, gp120, to the viral envelope and mediates viral envelope-cell membrane fusion following gp120-CD4 receptor-chemokine coreceptor binding. We have used mutation-directed chemical cross-linking with bis(sulfosuccinimidyl)suberate (BS3) to investigate the architecture of the gp41 oligomer. Treatment of gp41 with BS3 generates a ladder of four bands on sodium dodecyl sulfate-polyacrylamide gels, corresponding to monomers, dimers, trimers, and tetramers. By systematically replacing gp41 lysines with arginine and determining the mutant gp41 cross-linking pattern, we observed that gp41 N termini are cross-linked. Lysine 678, which is close to the transmembrane sequence, was readily cross-linked to Lys-678 on other monomers within the oligomeric structure. This arrangement appears to be facilitated by the close packing of membrane-anchoring sequences, since the efficiency of assembly of heterooligomers between wild-type and mutant Env proteins is improved more than twofold if the mutant contains the membrane-anchoring sequence. We also detected close contacts between Lys-596 and Lys-612 in the disulfide-bonded loop/glycan cluster of one monomer and lysines in the N-terminal amphipathic alpha-helical oligomerization domain (Lys-569 and Lys-583) and C-terminal alpha-helical sequence (Lys-650 and Lys-660) of adjacent monomers. Precursor-processing efficiency, gp120-gp41 association, soluble recombinant CD4-induced shedding of gp120 from cell surface gp41, and acquisition of gp41 ectodomain conformational antibody epitopes were unaffected by the substitutions. However, the syncytium-forming function was most dependent on the conserved Lys-569 in the N-terminal alpha-helix. These results indicate that gp160-derived gp41 expressed in mammalian cells is a tetramer and provide information about the juxtaposition of gp41 structural elements within the oligomer.  相似文献   
993.
Hemicorporectomy, literally translated, means half (hemi), body (corpus), removal (ectomy). The procedure is indicated as a last resort measure for patients with life-threatening conditions such as advanced pelvic tumors, pelvic osteomyelitis, crushing pelvic trauma, or intractable decubiti in the pelvic region. We report a case in which this mutilating procedure was performed on a 49-year-old man with extensive perineal and sacral sores. Squamous cell carcinoma was detected and isolated to the pelvic region. His medical history was significant for paraplegia secondary to a gunshot wound in 1966. The literature has documented fewer than 45 procedures of this radical nature. Few of the case studies specifically address the rehabilitation of this patient population and none of the articles researched were written from a physical therapy standpoint. Articles that addressed the concept of rehabilitation comment only that the course of rehabilitation was extensive and prolonged. This report provides an overview of the surgical procedures and specifically addresses the physical rehabilitation of this patient after his hemicorporectomy from a physical therapy perspective. This patient's physical therapy was accomplished over a time span of less than 1 month.  相似文献   
994.
The developmental toxicities of caffeine and 13 metabolites, including theophylline, and paraxanthine and a synthetic methylxanthine analogue 3-isobutyl-methylxanthine (IBMX) were evaluated using the Frog Embryo Teratogenesis Assay Xenopus (FETAX). Young X. laevis embryos were exposed to these compounds in each of two separate concentration-response experiments with and without an exogenous metabolic activation system (MAS). Results obtained from these studies indicated that relative teratogenic potencies of caffeine and each of its di- and monomethylxanthine metabolites were similar. Representatives of both the substituted uric and uracil metabolites were less developmentally toxic on an equimolar basis than the methylxanthines, suggesting that they may have represented detoxification metabolites. IBMX, a phosphodiesterase inhibitor also known to be an adenosine receptor antagonist, was the most potent developmental toxicant of the materials evaluated. In conclusion, none of the caffeine metabolites tested was found to be significantly more potent than caffeine itself in the FETAX assay.  相似文献   
995.
BACKGROUND: The levels of proliferating cell nuclear antigen (PCNA) are almost negligible in long-term quiescent cells and increase dramatically during the cell cycle. Recently, the monoclonal antibodies to PCNA have been used to demonstrate the proliferative component of paraffin-embedded tumor tissues. It has been shown to be available as a simple histological marker of proliferative activity and the PCNA labeling index has been correlated with the prognosis of several malignant neoplasms. METHODS: Formalin fixed, paraffin embedded tissue specimens of 29 primary pediatric rhabdomyosarcomas were immunostained by using an anti-PCNA monoclonal antibody (DAKO PCNA PC10). The relationship between the PCNA index and prognosis, clinicopathological features and survival were assessed retrospectively. RESULTS: The mean PCNA index for the whole series was 54%. There was no correlation between PCNA index and any of the clinicopathological characteristics. However, patients having tumors with a high (> 54%) PCNA index demonstrated significantly lower survival rates than tumors with a low (< 54%) PCNA index (P = 0.01). Moreover, there were significantly more patients with relapse or progressive disease in the high PCNA index group (P = 0.005). CONCLUSION: The PCNA labeling index can be a useful prognostic factor and a good indicator of recurrence and/or survival in patients with rhabdomyosarcoma.  相似文献   
996.
Sleep disorders are major syndromes that can interfere with falling to sleep or maintaining sleep, or produce excessive daytime sleepiness. Sleep disorders are rarely diagnosed in the elderly due to age-related changes in sleep patterns. Gerontological nurses can assist the elderly client to achieve improved sleep through increased awareness of sleep disorders, related assessment tools, and interventions.  相似文献   
997.
BACKGROUND: Many cardiovascular and noncardiovascular parameters are thought to be determinants of left ventricular mass (LVM). Complicated interactions necessitate the simultaneous measurement and consideration of each to determine their individual and collective impact on LVM. We undertook such a comprehensive study. METHODS AND RESULTS: The influence of anthropometry, cardiac size and contractility, arterial structure and function, as well as indices of lifestyle, physical activity, and dietary salt intake on LVM (by two-dimensionally guided M-mode echocardiography) was analyzed in 1315 Chinese subjects who were either normotensive or had untreated hypertension. Effects of many cardiac and arterial factors were assessed. In univariate analysis, almost all measured noncardiovascular, cardiac, and arterial variables were significantly correlated with LVM. In multivariate linear regression analyses, when age, sex, body habitus, fasting serum C-peptide level, dietary salt, physical activity, and lifestyle were accounted for, the optimum multivariate linear regression main effects model had an adjusted model r2 of 0.740, with 98% of the model variance accounted for by the 5 independent determinants of LVM: stroke volume (49.6%), systolic blood pressure (30.7%), contractility (14.7%), body mass index (1.8%), and aortic root diameter (1.6%). Other proposed arterial indices were significant independent determinants of LVM only when blood pressure was removed from the model and, even then, these indices not only resulted in less powerful prediction but also accounted for only a very small percentage of the total variance of LVM. CONCLUSIONS: In a large population, we (1) confirmed that age, body habitus, and some indexes of arterial structure and function are independent determinants of LVM; (2) found aortic diameter to be an independent structural determinant of LVM; (3) demonstrated that the effects of the derived measures of arterial function were small and provided no better predictive power than blood pressure alone; and (4) showed that when the best measures of cardiac and vascular load were included, the single most potent predictor was an index of left ventricular size.  相似文献   
998.
Physical loading creating high peak strains on the skeleton at high strain rates is suggested to be the most effective type of activity in terms of bone mineral acquisition. This study assessed the effects of sudden impact loading on mineral and mechanical bone properties in 13-week-old Sprague-Dawley rats. The rats were randomly assigned as sedentary controls (SED, n = 10), control animals receiving low-intensity exercise (EX, n = 15), and experimental animals receiving low-intensity exercise combined with sudden impact-loading (EX + IMP, n = 15). In the EX group, the rats walked in a walking mill at a speed of 10 cm/s for 20 minutes/day, 5 days/week for 9 weeks. In the EX + IMP group, the program was identical to the EX group except for the additional sudden impacts administered to their skeleton during the walking exercise. At the start, there were 50 impacts per session, after which their number was gradually increased to 200 impacts per session by week 6 and then kept constant until the end of the experiment, week 9. These horizontally and vertically directed body impacts were produced by a custom-made walking mill equipped with computer-controlled high-pressure air cylinders. After sacrifice, both femora of each rat were removed and their dimensions, bone mineral content (BMC) by dual-energy X-ray absorptiometry, and mechanical properties by femoral shaft three-point bending and femoral neck compression were determined. The cortical wall thickness increased significantly in the EX and EX + IMP groups as compared with SEDs (+7.6%, p = 0.049 and +10%, p = 0.020, respectively). The EX + IMP group showed +9.0% (p = 0.046) higher cross-sectional moment of inertia values than the EX group. No significant intergroup differences were seen in the BMC values, while the breaking load of the femoral shaft (EX + IMP vs. SED +8.8%,p = 0.047) and femoral neck (EX + IMP vs. SED +14.1%, p = 0.013) was significantly enhanced by the impact loading. In conclusion, this study indicates that mechanical loading can substantially improve the mechanical characteristics of a rat femur without simultaneous gain in its mineral mass. If this is true in humans too, our finding gives an interesting perspective to the numerous longitudinal exercise studies (of women) in which the exercise-induced gains in bone mass and density have remained mild to moderate only.  相似文献   
999.
Ewing's sarcoma, one of the most malignant tumors of children and young adults, expresses specific chimeric genes, e.g. EWS-FLI-1, EWS-ERG, EWS-ETV1 and EWS-FEV. In this paper, we extensively characterized a new fusion gene, EWS-EIAF by means of whole cDNA sequencing, RNA blot analysis, DNA blot analysis and chromosomal analysis, and showed it to be available for the diagnosis of Ewing's sarcoma and to participate in the oncogenesis of Ewing's sarcoma. Furthermore, we conducted a genetic analysis of Ewing family tumors in conjunction with immunohistochemical analysis and ultrastructural analysis. Our results demonstrate some limitations of both genetic analysis and histopathological analysis, and establish the relationship between neurogenic phenotypes and chimera genes.  相似文献   
1000.
BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia after open heart surgery. Traditional treatment with a range of antiarrhythmic drugs and electrical cardioversion is associated with considerable side effects. The aim of this study was to examine the feasibility and efficacy of low-energy atrial defibrillation with temporary epicardial defibrillation wire electrodes. METHODS AND RESULTS: Epicardial defibrillation wire electrodes were placed at the left and right atria during open heart surgery in 100 consecutive patients (age 65+/-9 years; male to female ratio 67:23). Electrophysiological studies performed postoperatively revealed a test shock (0.3 J) impedance of 96+/-12 omega (monophasic) and 97+/-13 omega (biphasic). During their hospital stay, AF occurred in 23 patients (23%) at 2.1+/-1.3 days postoperatively. Internal atrial defibrillation was performed in 20 patients. Of these patients, 80% (16/20) were successfully cardioverted with a mean energy of 5.2+/-3 J. Early recurrence of AF (< or =60 seconds after defibrillation) developed in 8 patients. Five patients had multiple episodes of AF. In total, 35 episodes of AF were treated, with an 88% success rate. Only 6 patients (30%) required sedation. No complications were observed with shock application or with lead extraction. CONCLUSIONS: Atrial defibrillation with temporary epicardial wire electrodes can be performed safely and effectively in patients after cardiac operations. The shock energy required to restore sinus rhythm is low. Thus, patients can be cardioverted without anesthesia.  相似文献   
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