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81.
82.
A bstract The purpose of this study was to assess the efficacy of nasal mask bi-level positive airway pressure (BiPAP) support in managing respiratory failure following cardiovascular surgery. A total of 20 patients requiring postoperative prolonged respiratory support of 72 hours or longer were studied. BiPAP support was used for eight patients (BiPAP group); the other 12 patients were managed using ordinary oxygen mask treatment (control group). The mean age of the BiPAP group and control group was 65 and 58 years of age, respectively. The mean period of postoperative endotracheal intubation of the BiPAP group and control group was 12 ± 5 days and 7 ± 1 days, respectively. Reintubation was necessary in two patients of the control group. The BiPAP group patients required no reintubation. BiPAP support was discontinued within 48 hours in 6 out of 8 patients. The respiratory rates of control group increased (p < 0.1) 24 hours after extubation, however, the respiratory rates of the BiPAP group remained unchanged. The values of the respiratory index of the BiPAP group improved significantly (p < 0.01) after BiPAP management (from 1.5 ± 0.2 to 0.9 ± 0.2). The values of the control group, however, remained unchanged. A-aDO2 and Qs/Qt decreased (p < 0.1) in the BiPAP group. There were no significant differences in central venous pressure or circulatory status between the two groups. In conclusion, BiPAP support is a noninvasive management technique for postoperative respiratory failure and may also prevent prolonged endotracheal intubation.  相似文献   
83.
The heating performance of prototype variable power control units attached to two domestic microwave ovens, 500 W and 700 W, was investigated. The units employed the phase control method where rated voltage was obtained by switching AC supply at a particular angular position on the sinusoidal voltage. In order to create experimental conditions employed in a previous study, Sydney tap water (50 mL) was heated at a 10% power level in the 500 W oven. Water boiled at 10 min in both experiments. However, the precision and control of the heating was greatly improved with addition of the control unit. A disinfecting solution (50 mL) and a tissue fixative (10 mL) were included for experiments with the 700 W oven. A power level of only 1% was sufficient to maintain the temperature of the fixative at low temperatures (30-40 degrees C) where many biological reactions occur. The present results indicate that microwave heating power can be controlled by the variable power control method. This will make temperature control possible through the provision of an electronic feedback loop which links a thermocouple with the power control unit.  相似文献   
84.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
85.
PURPOSE: The association of BRCA2 polymorphisms at codon 372 [Asn (N)/His (H)]and codon 784 [Met (M)/Val (V)] with breast cancer risk was evaluated in Japanese women. In addition, the prognostic significance of these polymorphisms was studied in breast cancer patients. EXPERIMENTAL DESIGN: A case-control study was conducted to examine the association of the BRCA2 N/H372 polymorphism and M/V 784 polymorphism with breast cancer risk (cases = 149, controls = 154). The prognostic significance of these polymorphisms was evaluated in 139 patients with primary breast cancer. RESULTS: No significant association was observed between the N/H372 polymorphism and breast cancer risk. In contrast, a significant increase in breast cancer risk (odds ratio, 2.03; 95% confidence interval, 1.07-3.87) was observed in carriers of the variant allele (V784) of the M/V784 polymorphism as compared with noncarriers after adjustment for the classical risk factors, age, family history, parity, body mass index, and so forth. Among breast cancer patients, various clinicopathological parameters including menopausal status, tumor size, lymph node status, histological grade, and estrogen-receptor status were not significantly different between the carriers and noncarriers of the variant allele with regard to both N/H372 and M/V784 polymorphisms. The N/H 372 polymorphism was not significantly associated with patient prognosis. On the other hand, breast cancer patients carrying the variant allele of M/V784 polymorphism showed a significantly (P = 0.014) lower 3-year disease-free survival rate (63%) than noncarriers (92%). Multivariate analysis has revealed that the M/V784 polymorphism is a significant prognostic factor, being independent of the other conventional prognostic factors such as lymph node status and estrogen receptor status. CONCLUSION: These results suggest that the M/V784 polymorphism, but not the N/H372 polymorphism, would be useful in the selection of women at high risk for developing breast cancer and would also serve as a clinically useful prognostic factor in breast cancer patients.  相似文献   
86.
40 specimens consisting of 27 carcinomas, 9 lymphomas, 2 thymomas, 1 sarcoma and 1 neurinoma were studied by immunoperoxidase technique to demonstrate a cell proliferation-associated antigen defined by proliferating cells (PC) antibody. Though PC antibody expression did not seem to correlate well with histologic grading of carcinomas, positivity to this was consistently more intense in carcinomas than in normal epithelia. Correlation with histologic grading of lymphomas was more significant: the high grade types, e.g. ATL, exhibited greater positivity than intermediate grade types, e.g. diffuse medium lymphoma and certainly much more than low grade types, e.g. follicular lymphomas. These data were compared to another proliferation-associated antigen, the transferrin receptor.  相似文献   
87.
Systemic acute rhinosinusitis therapy consists mostly of antibiotic treatment because pathogens play a major role. Amoxicillin is the drug of choice for treatment of acute rhinosinusitis, with second- and third- generation cephalosporins, azythromycin, clarithromycin, and telithromycin as possible options, especially in the case of allergy to amoxicillin. If the clinical course suggests that an anaerobic pathogen is more likely, clindamycin or metronidazole can be considered in combination with a broad-spectrum drug. In antimicrobial treatment of chronic sinusitis there is no consensus on treatment length, organism coverage, or which antibiotics are most effective because the bacteriology is variable with polymicrobial anaerobic and aerobic organisms present. Adjuvant therapies need to be proven by additional studies. Chronic rhinosinusitis is heterogeneous and treatment should vary according to the causative factor involved. Short courses of systemic steroids have been found very useful to decrease mucosal swelling and inflammation in chronic rhinosinusitis. However, no randomized controlled studies have been performed to validate their efficacy in children. A variety of other agents are used in the treatment of chronic rhinosinusitis including antihistamines, decongestants, and leukotriene modifiers. To date, there is no good evidence from randomized controlled studies to support the use of any of these agents in the treatment of this disease in either children or adults.  相似文献   
88.
89.
H Matsuura  H Kuwano  M Morita  S Tsutsui  Y Kido  M Mori  K Sugimachi 《Cancer》1991,67(5):1406-1411
Cytophotometric analysis of nuclear DNA content was done in 128 patients with squamous cell carcinoma of the esophagus. The relationship among histopathologic features, DNA distribution pattern, and survival time was investigated from the standpoint of recurrence. Of 128 patients, 77 (60.1%) died of recurrence within 2 years after surgery: 16 (12.5%) from 2 to 5 years and two (1.6%) over 5 years. The rate of death of recurrence within 2 years was higher in patients with T4 or N1 than T1, T2, and T3 or N0 (P less than 0.01). Survivors over 5 years more frequently possessed type II DNA pattern than types III and IV (P less than 0.05). The rate of death of recurrence within 2 years was 34.4% in type II, which was lower than the 59.6% rate in type III (P less than 0.05) and the 76.6% rate in type IV (P less than 0.01). Survivors from 2 to 5 years were higher in type III than in type IV (P less than 0.05), and recurrence over 5 years was found only in type II. This inclination was more apparent in those with curative resection. In the patients with type II, careful follow-up may be needed over 5 years for late recurrence. However, in those with type IV, no recurrence over 2 years could be regarded as healed because most of their recurrences occur within 2 years. These findings suggest that the growth rate of esophageal carcinoma should reflect DNA aneuploidy, and the DNA analysis of esophageal carcinoma should be a valuable parameter for postoperative follow-up planning.  相似文献   
90.
The motor end-plate fine structure was studied in 3 patients with type A botulism and compared with that in 4 patients with Lambert-Eaton myasthenic syndrome (LES). In the botulism cases a biopsy of the biceps brachii muscle was performed at the chronic stage. The skeletal muscle showed a neurogenic change. The nerve terminal area had decreased and the postsynaptic regions had been denuded of their nerve terminals in 16% of the regions (9.8% in control). No highly simplified postsynaptic regions were observed. The findings are consistent with those observed at the motor end-plates in motoneuron diseases. By contrast, in LES no changes were observed in the presynaptic region. In the postsynaptic region, the postsynaptic membrane length and membrane density decreased and hypertrophy of the junctional folds was not observed.  相似文献   
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