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991.
992.
Tracheoesophageal fistula (TEF) without atresia is rare and usually presents with symptoms from birth. In this report, a 9-year-old boy presented with productive cough of 4 month's duration and was shown to have a right lung abscess seen on chest radiograph. His parents denied earlier respiratory symptoms or illnesses. Rigid bronchoscopy showed a fistulous opening of about 1 mm in diameter in the posterior wall of the trachea about 16 cm from the upper incisor teeth. Cannulation with a ureteral catheter demonstrated that the fistulous opening communicated with the esophageal lumen. The tracheoesophageal fistula was 1 cm long and was divided through a right supraclavicular incision. The postoperative period was uneventful, and the patient was discharged on the third postoperative day. This case demonstrated that TEF should be considered in any patient presenting with chronic respiratory problems even after a prolonged symptom-free period.  相似文献   
993.
A method for the generation of hot dip galvanized sheet steel Certified Reference Materials (CRMs) certified for coating mass is described. The method produces high quality coating mass CRMs with combined estimated uncertainties (95% confidence) of about 3% relative standard deviation (rsd). Initially, coating mass x-ray fluorescence (XRF) data are collected on multiple test specimens and used to sort the test specimens by observed coating mass. Several specimens near the mean of the sorted data are retained and the remaining specimens are analyzed for coating mass by a National Institute for Standards and Testing (NIST) traceable weigh-strip-weigh analytical method. The weigh-strip-weigh data are correlated to the initial XRF data using statistical techniques. The retained specimens’ coating masses are calculated using this relationship and are used as the certified coating masses for the retained specimens. This correlation method is a more accurate and efficient technique relative to the traditional “perimeter” certification methods. The present method does not suffer from an increased estimated uncertainty due to the inherent hot dip Zn coating variability. Also, this method provides a simple means to generate NIST traceable high quality CRMs that can be tailored to meet individual users’ requirements.  相似文献   
994.
995.
The Ziehl-Neelsen (ZN) stain is important in identifying organisms that are acid fast, principally Mycobacterium tuberculosis. However, decolorisation with a weaker acid concentration (for example 1% hydrochloric acid), often used in ZN staining in histology, can result in a wider variety of organisms appearing acid fast and can be a cause of misidentification. To illustrate this point, a patient is described with pulmonary nocardiosis who was misdiagnosed as having tuberculous empyema on pleural biopsy.  相似文献   
996.
To study effort tolerance in elderly women with different physical activity backgrounds, 52 physically active (PA) and 42 sedentary control women (CO) aged 66-85 yr were assigned to perform cycle ergometer exercise to their volitional maximum. Oxygen uptake, respiratory exchange ratio (RER), heart rate, work power, and rate pressure product were measured to evaluate the severity of exercise. Plasma C-ANP (C-terminus of the atrial natriuretic peptide prohormone) and plasma N-ANP (N-terminus of the atrial natriuretic peptide prohormone) were analyzed as indicators of cardiac load. Eighty-one percent (N = 42) of the PA and 52% (N = 22) of CO performed the ergometer exercise. The mean peak oxygen uptake was 22.6 and 15.1 mL x kg(-1) x min(-1) among PA and CO, respectively. Twenty-two of the 42 PA and 19 of the 22 CO terminated the ergometer exercise before attaining the objective maximum. The most common reasons for termination were the subject's own wish, abnormal cardiovascular response, or lower limb tiredness. Both C-ANP and N-ANP increased after exercise. The increase in plasma C-ANP correlated significantly with a few physiological variables, whereas comparable associations with N-ANP were not found. It is concluded that inexperience of physical exertion and medical as well as physiological factors limit effort tolerance among elderly women. Differences in the response of C-ANP and N-ANP were found that are suggested to be due to differences in the postsecretory mechanisms between these hormones.  相似文献   
997.
The causes and clinical manifestations of Clostridium difficile infection in children are described in this report. The studies were performed on three children aged up to 3 years. Risk factors as well as possible diagnostic and therapeutic procedures are discussed.  相似文献   
998.
BACKGROUND: In-vitro and in-vivo studies demonstrated the radiosensitizing effect of interferon beta on malignant tumor tissue as well as simultaneously a radioprotective effect on normal lung tissue. In this phase II study the outcome of combining radiotherapy with interferon beta in patients with advanced non-small cell lung cancer was evaluated. PATIENTS AND METHOD: From February 1994 until November 1996 14 patients with non-small cell lung cancer, stage IIIB were treated with locoregional radiation up to 59.4 Gy, with daily doses of 1.8 Gy and 5 fractions per week. Five million units of interferon beta (Fiblaferon) were given intravenously immediately preceding radiotherapy on the first 3 days of week 1, 3 and 5. RESULTS: Four of 14 patients (28.6%) showed complete response and 7 patients (50%) partial response, resulting in an overall response rate of 78.6%. After a mean follow-up time of 23.3 months the 1-, 2- and 3-year survival rates were 56.3%, 37.5% and 37.5%, respectively. The median survival time was 13 months. Three of 14 patients (21.4%) suffered from 7 Grade-3 acute side effects and 2 patients (14.3%) from 1 Grade-3 late toxicity in each case. One further patient, whose right lung was resected 3 months after completion of radiotherapy, developed as a consequence of this operation 2 Grade-4 complications. CONCLUSION: Considering the toxicity and the preliminary results of combining irradiation and interferon beta in the treatment of locally advanced non-small cell lung cancer it seems, that this procedure is worth to be tested in a phase III study.  相似文献   
999.
1000.
Guide RNAs (gRNAs) have been proposed to mediate uridine (U) addition/deletion editing of mitochondrial mRNAs in kinetoplastid protozoa. The Us are proposed to be derived either from UTP by two successive cleavage-ligations or transesterifications, or from the 3' end of the gRNA by the same mechanisms. We have demonstrated gRNA-dependent U insertions into a specific editing site of a pre-edited mRNA which was incubated in a mitochondrial extract from Leishmania tarentolae. The predominant number of U insertions was determined by the number of guiding nucleotides in the added gRNA, and the formation of a gRNA-mRNA anchor duplex was necessary for activity. UTP and alpha-beta bond hydrolysis of ATP were required, and the activity was inhibited above 50-100 mM KCl. A gRNA-independent insertion of up to approximately 13 Us occurred in the absence of the added cognate gRNA; the extent of this activity was affected by sequences upstream and downstream of the edited region. Heparin inhibited the gRNA-independent U insertion activity and had no effect on the gRNA-dependent activity. Blocking the 3' OH of the gRNA had little effect on the gRNA-dependent U insertion activity. The data are consistent with a cleavage-ligation model in which the Us are derived directly from UTP.  相似文献   
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