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991.
Fiber-optic biosensors that are selective for nitric oxide and do not respond to most potential interferents have been prepared with cytochromes c'. Both micro- and nanosensors have been prepared, and their response is fast (< 1 s), reversible, and linear up to 1 mM nitric oxide. The detection limit is 20 microM, making the sensor useful for some biological samples, such as the macrophages studied here. While sensors have been prepared based on the fluorescence of the cytochromes c', optodes with greatly enhanced signal-to-noise ratios have been made by labeling the cytochrome c' with a fluorescent dye. Comparisons of cytochromes c' from three species of bacteria as well as of two matrixes were performed and the optimum sensor configuration is described. 相似文献
992.
IP Dudanov GA Sharshavitski? AM Mezhenin GP Chekulaeva EM Libiia?nen IuV Andreev AA Bogdanets OD Morozov 《Canadian Metallurgical Quarterly》1998,157(3):67-69
The authors dealt with treatment of 112 patients aged 27-70 years with the Mallory-Weiss syndrome. The diagnosis was confirmed by esophagogastroduodenoscopy. Diathermocoagulation was used in order to arrest bleeding. In profuse bleeding the margins of the mucosa fissures were first infiltrated with a solution of adrenaline. The Blakemore [correction of Bleikmorr] probe compression method was also used. Organ-saving operations were performed for continuing and recurrent bleedings. Two elderly patients with severe coexistent disease died. The authors consider that patients with the Mallory-Weiss syndrome must be treated by conservative methods. Operations for disruptions of the esophagus mucosa and acute blood loss will entail great risk. 相似文献
993.
BACKGROUND: The purpose of this study was to determine cost of care for leg ulcers in sickle cell patients and suggest an improved modality in ulcer care. STUDY DESIGN: We performed a retrospective study of a group of sickle cell disease patients with leg ulcers. RESULTS: Eighteen patients with a leg ulcer (duration: mean, 53.7 months), sickle cell disease, and a mean of 20.7 years of age had various modalities of treatment with the only consistency in healing being a commercial moist-wound dressing. CONCLUSIONS: There is no consistency in the treatment of the sickle cell patient with a leg ulcer. Treatment with a moist dressing had the best results. 相似文献
994.
995.
996.
CE Swanson GA Day CE Yelland JR Broome L Massey HR Richardson K Dimitri A Marsh 《Canadian Metallurgical Quarterly》1998,169(10):515-518
Retroperitoneal fibrosis is an uncommon collagen vascular disease. Back pain with no specific radiation pattern is a common finding. Evaluation usually begins with an abdominal CT scan or MRI. The finding of fibrous periaortic tissue in conjunction with an elevated erythrocyte sedimentation rate supports the diagnosis. A biopsy is necessary to confirm the diagnosis and exclude malignancy. Sometimes retroperitoneal fibrosis can progress to the point of causing bilateral ureteral obstruction leading to acute renal failure. Corticosteroids, in conjunction with surgery when needed, are the mainstay of therapy. 相似文献
997.
To determine the effect of extending the duration of ammonia (2% dry matter basis) treatment ti'om 1 to 5 wk on the toxicity of endophyte-infected tall fescue seed, 60 male Harlan Sprague-Dawley rats were randomly assigned to the following six treatments during a 28-d trial: endophyte-free (E-), endophyte-infected (E+), 1 wk ammoniated endophyte-fee (1AE-), 1 wk ammoniated endophyte-infected (1AE+), 5 wk ammoniated endophyte-free (5AE-), and 5 wk ammoniated endophyte-infected (5AE+) tall fescue seed. The concentration of total pyrrolizidine alkaloids (N-acetyl and N-formyl loline) or E+ rescue was reduced from 4203 12 g/g to 3009 and 2533 I-tg/g by the 1AE+ and 5AE+ treatments, respectively. Ergovaline was lowered from 3.77 to 1.57 12 g/g by 1AE+ and eliminated by 5AE+. Endophyte-infected treatment groups had depressed (P < 0.0001) dally feed intakes (DFI), daily weight gains (DWG), feed efficiencies (G/F), primary antibody responses, and T cell and B cell mitogenic responses than endophyte-free treatment groups. Ammoniation of endophyte-infected rescue seed improved DFI and DWG (P < 0.0001) and G/F (P < 0.05); however, there was no difference in performance criteria between the 1-wk and 5-wk ammoniation treatments. Endophyte-induced depressions in immune function were not alleviated by ammoniation. 相似文献
998.
RD Bloebaum GA Lundeen KN Bachus I Ison AA Hofmann 《Canadian Metallurgical Quarterly》1998,40(1):104-114
The optimum 14N pulse lengths in the 13C-14N rotational-echo adiabatic-passage double-resonance (REAPDOR) NMR experiment are determined from calculations and from experiments on samples of glycine and L-alanine. The REAPDOR experiment utilizes the adiabatic passages that 14N spins make between the 14N Zeeman energy levels during the application of a single, short 14N radiofrequency pulse. Use of a short 14N irradiation time of less than one-quarter of a rotor period ensures that the number of 14N spins that undergo more than one passage is minimized. This simplifies calculations describing 13C dipolar dephasing and provides better agreement between calculations and experiments. Recovery of the 13C-14N dipolar couplings and 14N quadrupolar coupling constants and asymmetry parameters is described. 相似文献
999.
1000.
EN Mendeloff CB Huddleston GB Mallory EP Trulock AH Cohen SC Sweet J Lynch S Sundaresan JD Cooper GA Patterson 《Canadian Metallurgical Quarterly》1998,115(2):404-13; discussion 413-4
OBJECTIVE: This paper was undertaken to review the experience at our institution with bilateral sequential lung transplantation for cystic fibrosis. METHODS: Since 1989, 103 bilateral sequential lung transplants for cystic fibrosis have been performed (46 pediatric, 48 adult, 9 redo); the mean age was 21 +/- 10 years. Cardiopulmonary bypass was used in all but one pediatric (age <18) transplant, and in 15% of adults. RESULTS: Hospital mortality was 4.9%, with 80% of early deaths related to infection. Bronchial anastomotic complications occurred with equal frequency in the pediatric and the adult populations (7.3%). One- and 3-year actuarial survival are 84% and 61%, respectively (no significant difference between pediatric and adult age groups; average follow-up 2.1 +/- 1.6 years). Mean forced expiratory volume in 1 second increased from 25% +/- 9% before transplantation to 79% +/- 35% 1 year after transplantation. Acute rejection occurred 1.7 times per patient-year, with most episodes taking place within the first 6 months after transplantation. The need for treatment of lower respiratory tract infections occurred 1.2 times per patient in the first year after transplantation. Actuarial freedom from bronchiolitis obliterans was 63% at 2 years and 43% at 3 years. Redo transplantation was performed only in the pediatric population and was associated with an early mortality of 33%. Eight living donor transplants (four primary transplants, four redo transplants) were performed with an early survival of 87.5%. CONCLUSION: Patients with end-stage cystic fibrosis can undergo bilateral lung transplantation with morbidity and mortality comparable to that seen in pulmonary transplantation for other disease entities. 相似文献