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Changes in complete blood count (CBC), bone marrow, reticulocyte count, coagulation profile, biochemical analysis, and serum iron, transferrin, and immunoglobulin M (IgM) concentrations were measured three and 10 days after splenectomy in 12 dogs. Spleens were cultured aerobically for bacteria and submitted for histopathological evaluation in 23 dogs undergoing splenectomy. There were no consistent changes in red blood cell (RBC), white blood cell (WBC), or platelet counts; bone-marrow samples; or biochemical profiles. Serum iron, transferrin, and IgM concentrations remained normal. Eight (35%) bacterial cultures yielded growth. Five of the 23 dogs had pyrexic episodes two-to-five days after surgery. In contrast to previous reports done on healthy dogs, this study shows that dogs with splenic disease have no characteristic changes in hematological or biochemical parameters after splenectomy. Rather, the changes tended to reflect the primary disease process. Splenic vascular compromise or a decrease in processing of bacteria may have resulted in the bacterial growth. There was no direct correlation to pyrexic postoperative episodes. 相似文献
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Bis-(4-methyl-1-homopiperazinylthiocarbonyl)-disulphide (FLA-63) inhibits in vitro purified bovine adrenal medullary dopamine beta-hydroxylase (BDH) concentration-dependently; 50% inhibition is produced by 2 x 10(-6)M FLA-63. Spectrophotometric experiments show that FLA-63 is reduced by ascorbate very likely to the corresponding dithiocarbamate-derivative, which acts as a Cu++-chelator. Cu++-ions are able to completely abolish the inhibition of the DBH caused by FLA-63 in concentrations up to 2.5 x 10(-6)M. It is concluded that FLA-63 inhibits the DBH mainly in its reduced form via the formation of a chelate-complex with copper ions derived from the DBH. 相似文献
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BA Revich AA Bykov SM Liapunov AM Prikhozhan IF Ser?gina MB Sobolev 《Canadian Metallurgical Quarterly》1998,(12):25-32
Lead releases in Belovo town containing metallurgy enterprise had reached 120 tons/year earlier, but in recent years have decreased to 9 tons/year. Reduction of the production induced decrease of lead levels in the ambient air from 0.7-2.3 mg/m3 in 1994 to 0.001-0.24 mg/m3. Lead concentration in the soil ranges from 30 to 3000 mg/kg. Lead levels were measured in serum of 91 children, in hair of 67 ones and in teeth of 15 children. Serum lead levels in children aged 7-8 years varied from 0.5 to 39 mg/dl, with an average of 9.9 mg/dl (SD is 5.2 mg/dl), geometric mean is 8.5 mg/dl and error of geometric mean is 3.3. 46% of the children had serum lead levels exceeding the normal one (10 mg/dl). Average lead level in the hair equaled 4.5 mg/g (SD is 4.9 mg/g). The children living in towns with higher environmental lead levels demonstrated more frequent anxiety and changes in higher psychic functions. The major points influencing the serum lead level are proximity to highway, dietary load of goods grown near the residence, mother's smoking. Biokinetic model describing lead transfer into the blood helped to evaluate various modes of the enterprise functioning and efficiency of some environmental protection measures. The most efficient are measures aimed to lower dietary intake of lead, less efficiency is associated with measures reducing lead levels in air, dust and soil. 相似文献
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LS Dean M Mickel R Bonan DR Holmes WW O'Neill IF Palacios S Rahimtoola JN Slater K Davis JW Kennedy 《Canadian Metallurgical Quarterly》1996,28(6):1452-1457
OBJECTIVES: This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry. BACKGROUND: The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short- and long-term safety and efficiency of percutaneous balloon mitral commissurotomy. METHODS: Between November 1987 and October 1989, 736 patients > or = 18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years. RESULTS: The actuarial survival rate was 93 +/- 1% (mean +/- SD), 90 +/- 1.2%, 87 +/- 1.4% and 84 +/- 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomy at 1 year. The event-free survival rate was 80 +/- 1.5% at 1 year, 71 +/- 1.7% at 2 years, 66 +/- 1.8% at 3 years and 60 +/- 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age > 70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01). CONCLUSIONS: Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients. 相似文献