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991.
SL Dzemeshkevich AS Ivanov IE Rykunov LM Kuznetsova NA Trekova IV Poplavski? AE Belous IL Zhidkov Kh Koseros AA Eremenko NI Chaus 《Canadian Metallurgical Quarterly》1998,(6):49-53
Standard technique of establishment of interatrial anastomoses allows to carry out orthotopic transplantation of the heart quickly and reliably. However the accumulation of collective experience evidences about a number of unavoidable shortcomings of such operation: rhythm disturbances, worsening of hemodynamics in discordant atrial contractions of recipient and donor, atrio-ventricular valve insufficiency, thromboembolism, coronary fistulas. Since 1990 in RRCS 25 operations were carried out with the use of standard technique and we also met with the risk of developing the above complications. In experiment on 30 mongrel dogs the technique of anatomical, truly orthotopic transplantation of the heart with six anastomoses was developed: left pulmonary veins with a common cuff, separate anastomoses of the superior and inferior caval veins, anastomoses of aorta and pulmonary artery. Particular attention was paid to developing of original surgical modes for prophylaxis of stenoses in the area of anastomoses of pulmonary and caval veins. In 1997 the anatomical technique of heart transplantation was successfully introduced by us into clinical practice. Clinical electrophysiological, echocardiographic and functional examinations have confirmed the results of the experiments and have evidenced for substantial advantages of the anatomical technique of orthotopic transplantation of the heart. By reliability the new operation is not inferior to standard method of N. Shumway. 相似文献
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993.
S Mikocki JR Ficenec S Torres WP Trower TY Chen EW Jenkins KW Lai J LeBritton YC Lin AE Pifer HC Fenker DR Green JR Albright JH Goldman SL Hagopian JE Lannutti JE Piper CC Chang TC Davis RN Diamond KJ Johnson JA Poirier A Napier J Schneps JM Marraffino JW Waters MS Webster EG Williams 《Canadian Metallurgical Quarterly》1986,34(1):42-52
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995.
Twenty prepuberal Charolais X Brahman-Hereford heifers were randomly assigned to be fed a concentrate containing either 0 mg (C) or 200 mg (M) monensin sodium/head/day. Coastal bermudagrass hay was fed ad libitum. Average daily gain was similar for the two groups. Each heifer received 1 mg of porcine follicle stimulating hormone (FSH-P) (Armour) at 0800 and 2000 hr on days 22 through 26 (10 mg total) and 2,500 IU human chorionic gonadotropin (HCG) on day 27. Flank laparotomy was performed on day 30, for examination of ovaries, and ovariectomy was performed on day 37. The average ovarian size +/- standard error at day 15 ws 3,730 +/- 66 mm3 and 1,848 +/- 55 mm3 for groups M and C, respectively (P < .025), as measured by rectal palpation. Numbers of ovulation sites measured on day 30 were 9.1 +/- 2.2 and 4.9 +/- 1.8 per heifer for groups M and C, respectively (P < .01). After ovariectomy on day 37, heifers fed M were found to have greater ovarian weight (P < .05), more corpora lutea (CL) (P < .05), greater total luteal weight (P < .05), more follicles (P < .01) and greater weight of follicular fluid (P < .05) and stroma (P < .025) than controls. CL were analyzed for progesterone content by spectrophotometric procedures. Heifers fed M had slightly larger CL (P < .10) with progesterone concentrations similar to those in CL from controls. This resulted in more luteal progesterone per CL and more luteal progesterone per heifer in the M heifers than in the controls. Prepuberal heifers fed M, which caused the expected shifts in rumen fermentation and volatile fatty acid production, exhibited an enhanced ovarian response to gonadotropins compared to that exhibited by controls. 相似文献
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998.
Bronchoalveolar lavage neutrophilia is associated with obliterative bronchiolitis after lung transplantation: role of IL-8 总被引:1,自引:0,他引:1
B DiGiovine JP Lynch FJ Martinez A Flint RI Whyte MD Iannettoni DA Arenberg MD Burdick MC Glass CA Wilke SB Morris SL Kunkel RM Strieter 《Canadian Metallurgical Quarterly》1996,157(9):4194-4202
Obliterative bronchiolitis (OB) is a devastating complication in lung transplantation. We postulated that the pathogenesis of OB is mediated, in part, by neutrophils. We serially collected bronchoalveolar lavage (BAL) fluid from lung transplant recipients. Patients were divided into two groups depending on the presence or absence of OB. Samples from patients who never developed OB were further divided according to whether rejection was present. These samples were labeled healthy or rejection. Samples from patients who developed OB were divided according to whether the sample was obtained before (future OB) or at the time of diagnosis of OB (OB). The OB group, as compared with the healthy and rejection group, had significantly elevated neutrophil counts (3.9 x 10(5) +/- 1.8 x 10(5) vs 0.3 x 10(5) +/- 0.07 x 10(5) and 0.4 x 10(5) +/- 0.1 x 10(5), respectively, p < 0.01 for both) and levels of IL-8 (3131 +/- 1468 pg/ml vs 240 +/- 62 pg/ml and 172 +/- 47 pg/ml, p < 0.01 for both). Furthermore, we demonstrated immunolocalization of IL-8 associated with alpha smooth muscle actin-positive cells in the peribronchial region of OB. To confirm that the IL-8 present in BAL fluid from patients with OB was bioactive, we performed neutrophil chemotaxis experiments that showed that IL-8 accounted for a significant amount of the neutrophil chemotactic activity. We also found a trend toward higher levels of neutrophils and IL-8 in BALs from the future OB as compared with the healthy group (7.1 x 10(4) +/- 4.2 x 10(4) vs 3.4 x 10(4) +/- 0.7 x 10(4) and 500 +/- 306 pg/ml vs 240 +/- 62 pg/ml). In conclusion, we have provided the novel observation that in lung transplant recipients with OB, neutrophilia is present and highly correlated with the presence of IL-8. 相似文献
999.
We have investigated the mechanism whereby nuclear DNA fragmentation activity emerging during early apoptosis is inhibited during normal cell life. In a cell-free system, cytosol fractions from diverse nonapoptotic human cell lines (Jurkat T-cell leukemia, HeLa carcinoma, SK-N-MC neuroblastoma, and WI-38 embryonic lung fibroblast) potently neutralized the nuclear DNA fragmentation activity of cytosol from apoptotic anti-Fas treated Jurkat cells. Recombinant human DNA fragmentation factor 45 kDa subunit (DFF45/ICAD), an inhibitor of the caspase-activated DNase DFF40/CAD, substituted for healthy cytosol in inhibiting DNA fragmentation. An antiserum against human DFF45 detected 44 and 34 kDa proteins (major and minor, respectively) in the cytosols but not in the nuclear or membrane fractions of various cultured human cells. Cytosols depleted of DFF45/ICAD by immunoadsorption had little or no inhibitor of nuclear DNA fragmentation activity and no caspase-activated DNA fragmentation activity. We conclude that immunoreactive DFF45/ICAD is the principal inhibitor of apoptotic DNase activity in the cytosol of healthy cells. 相似文献
1000.
BACKGROUND: Although many community hospitals and trauma centers reuse external fixator components, no published studies have examined the cost-effectiveness or the effect on the rate of complications of reuse. This study reports the preliminary results of a program for the reuse of selected components of external fixators at a trauma center. METHODS: After removal from the patient, fixators were cleaned and examined by a single nurse responsible for the program. Components in good repair were returned to the operating room stock for reuse, whereas those showing specific signs of wear were discarded. No component was used more than three times. The medical center charged patients a loaner fee equal to the hospital's cost for reusable components of external fixators. Data were collected for all fixators applied in the 15 months before and after institution of the program (69 and 65 fixators, respectively). RESULTS: The overall mean hospital charge for a fixator decreased 32% as a result of the reuse program (from $4,067 to $2,791). For the two fractures most commonly treated with external fixation, the distal radius and tibial plafond fractures, the mean charge decreased 44 and 29%, respectively. The mean hospital cost for a fixator decreased 34% as a result of the program (from $1,864 to $1,238). There were no differences in the rates of reoperation or complications before and after institution of the reuse program. No patient had mechanical failure of a new or reused fixator body. CONCLUSION: The preliminary results of this program are encouraging. We recommend that institutions reusing these devices develop specific programs outlining criteria for reuse and guidelines for reprocessing devices for reuse. The results of this study represent an important first step in the validation of the efficacy and safety of reuse of external fixator components. 相似文献