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101.
102.
The postoperative diagnostic imaging examinations of 44 children who underwent 59 orthotopic liver transplantations were reviewed. The imaging modalities used for the evaluation of suspected complications include plain roentgenography, ultrasonography (US), computed tomography (CT), nuclear scintigraphy, arteriography, percutaneous and operative cholangiography, and endoscopic retrograde cholangiopancreatography. The main postoperative complications included ischemia, thrombosis (hepatic artery and portal vein), infarction, obstruction or leakage of the biliary anastomosis, hepatic and perihepatic infection, and allograft rejection. US, the most frequently used abdominal imaging modality, was best suited for detection of biliary duct dilatation, fluid collections in or around the transplanted liver, and hepatic arterial, inferior vena caval, and portal vein thrombosis. CT was especially helpful in corroborating findings of infection and in locating abscesses. Technetium 99m sulfur colloid (early- and late-phase imaging) provided a sensitive, although nonspecific, means of assessing allograft vascularization and morphology. Angiography showed vascularity most clearly, and cholangiography was the most useful in the assessment of bile duct patency. A diagnostic imaging algorithm is proposed for evaluation of suspected complications.  相似文献   
103.
Jagels  MA; Chambers  JD; Arfors  KE; Hugli  TE 《Blood》1995,85(10):2900-2909
We previously demonstrated in rabbits that various neutrophil chemotactic factors share an ability to induce recruitment of polymorphonuclear leukocytes (PMN) from bone marrow when administered intravenously (Jagels and Hugli, J Immunol 148:1119, 1992). In the study reported here, we investigated the effects of chemotactic factors on the expression of beta 2 integrins and L-selectin in vivo and the roles of these adhesionmolecules in the recruitment process. Leukocytosis was induced by infusion of either C5a (5 micrograms/kg), N- formyl-methionyl-leucyl-phenylalanine (f-MLP; 2.5 micrograms/kg), or tumor necrosis factor alpha (TNF-alpha; 100 ng/kg). C5a increased the expression of CD18 (the common subunit of beta 2 integrins) on PMN by nearly twofold and decreased levels of L-selectin by 50% within 15 minutes after administration. Levels of beta 2 integrins returned to baseline 2 to 3 hours after induction of leukocytosis. L-selectin remained depressed for more than 5 hours, demonstrating that shedding was induced in the recruited bone marrow leukocytes as well as in circulating PMN. In contrast to the response to C5a, TNF-alpha did not cause upregulation of CD18 or shedding of L-selectin. Levels of L- selectin were consistently increased 60 minutes after administration of TNF-alpha, coinciding with a rapid rise in the number of band-form PMN in the circulation. Intact IgG and F(ab)2 forms of the anti-CD18 monoclonal antibody IB4 or the anti-L-selectin antibody DREG-200 were administered intravenously 15 minutes before induction of leukocytosis by the chemotactic factors. Neither IB4 nor its F(ab)2 fragments blocked leukocytosis induced by C5a, f-MLP, or TNF-alpha. DREG-200 also did not block leukocytosis induced by f-MLP, C5a, or TNF-alpha. These results suggest that leukocyte emigration from the bone marrow into the circulation proceeds through interactions distinct from those involved in neutrophil chemotaxis and diapedesis. Shedding of L-selectin from C5a-recruited bone marrow leukocytes demonstrates activation of these cells in the recruitment process and may reflect a potential mechanism for their release. The dissimilar effects of C5a and TNF-alpha on expression of adhesion molecules may result from distinct stimulatory pathways and suggests differential activation states for cellular recruitment by these inflammatory factors.  相似文献   
104.
简化注射用头孢菌素无菌检查法的探讨   总被引:3,自引:1,他引:3  
目的:完善头孢菌素类药物注射剂的无菌检验方法标准。方法:以7种不同代注射用头孢菌素为例,通过对阳性对照菌,冲洗量及青霉素酶的加入顺序等条件的选择,建立了无菌检查方法。结果:不同代头孢菌素因抗菌谱的差异,对不同验证菌株的敏感性显著不同;无菌检查法必须建立在验证试验的基础上。结论:头孢菌素无菌检查方法的验证菌株可由目前2005年版中国药典规定的5株简化为2株,并从中选择最敏感的菌株作为无菌检查中的阳性菌株,即可保证无菌检查方法的有效性。  相似文献   
105.
The biokinetics of inhaled plutonium were analyzed using compartment models representing their behavior within the respiratory tract, the gastrointestinal tract, and in systemic tissues. The processes of aerosol deposition, particle transport, absorption, and formation of a fixed deposit in the respiratory tract were formulated in the framework of the Human Respiratory Tract Model described in ICRP Publication 66. The values of parameters governing absorption and formation of the fixed deposit were established by fitting the model to the observations in 530 autopsy cases. The influence of smoking on mechanical clearance of deposited plutonium activity was considered. The dependence of absorption on the aerosol transportability, as estimated by in vitro methods (dialysis), was demonstrated. The results of this study were compared to those obtained from an earlier model of plutonium behavior in the respiratory tract, which was based on the same set of autopsy data. That model did not address the early phases of respiratory clearance and hence underestimated the committed lung dose by about 25% for plutonium oxides. Little difference in lung dose was found for nitrate forms.  相似文献   
106.
A method is presented to determine the uncertainties in the reported dose due to incorporated plutonium for the Mayak Worker Cohort. The methodology includes errors generated by both detection methods and modeling methods. To accomplish the task, the method includes classical statistics, Monte Carlo, perturbation, and reliability groupings. Uncertainties are reported in percent of reported dose as a function of total body burden. The cohort was initially sorted into six reliability groups, with "A" being the data set that the investigators are most confident is correct and "G" being the data set with the most ambiguous data. Categories were adjusted based on preliminary calculation of uncertainties using the sorting criteria. Specifically, the impact of transportability (the parameter used to describe the transport of plutonium from the lung to systemic organs) was underestimated, and the structure of the sort was reorganized to reflect the impact of transportability. The finalized categories are designated with Roman numerals I through V, with "I" being the most reliable. Excluding Category V (neither bioassay nor autopsy), the highest uncertainty in lung doses is for individuals from Category IV-which ranged from 90-375% for total body burdens greater than 10 Bq, along with work histories that indicated exposure to more than one transportability class. The smallest estimated uncertainties for lung doses were determined by autopsy. Category I has a 32-38% uncertainty in the lung dose for total body burdens greater than 1 Bq. First, these results provide a further definition and characterization of the cohort and, second, they provide uncertainty estimates for these plutonium exposure categories.  相似文献   
107.
The oxidant resistance of low-density lipoproteins was shown in patients with metabolic cardiovascular syndrome to be reduced versus healthy donors. A changing total antiradical activity of blood serum is an important factor for such reduction of the antioxidant resistance in the above pathology. The level of tocopherol in blood serum could be the most significant chain determining the mentioned activity in patients with metabolic cardiovascular syndrome.  相似文献   
108.
109.
Interaction between the natural ceolite clinoptilolite and cell suspensions has been investigated using rat peritoneal macrophages and erythrocytes. The ceolite under study has been demonstrated to exhibit a high hemolytic activity and cytotoxicity. The viability of macrophages was evaluated from the incorporation of trypane blue. The ability of macrophages to phagocytosis was measured by chemiluminescence with luminol. The modification of clinoptilolite surface by ammonia ions led to a decrease in its cytotoxic properties. Ethanol, mannit and sodium azide did not affect whereas catalase appreciably reduced the ability of CPT to damage the membranes of macrophages and red cells. The role of hydrogen peroxide in the mechanism of cell membrane damage is discussed.  相似文献   
110.
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