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1.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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应用肝脏原位灌注模型,探讨了内皮素1(ET1)在内毒素所致肝损伤中的作用。选用Wistar大鼠24只,分为对照组、ET1组、内毒素组、内毒素+ET1抗体组。观察了肝组织中ET1、一氧化氮(NO)、前列环素(PGI2)、乳酸脱氢酶(LDH)、丙二醛(MDA)、三磷酸腺苷(ATP)和肝组织学变化。结果显示:内毒素能使肝组织ET1含量增加;内毒素和ET1均能使细胞脂质过氧化物形成和酶的漏出,还能使肝细胞浊肿变性;ET1抗体能部分拮抗内毒素所致的肝损伤。结果表明:ET1参与了内毒素所致的肝损伤作用。  相似文献   
4.
We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed.  相似文献   
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Amiodarone is an iodinated antiarrhythmic agent that is effective in the treatment of atrial and ventricular arrhythmias. A number of side effects are seen, including pulmonary toxicity and thyroid dysfunction. A patient with both amiodarone-induced pneumonitis and hyperthyroidism who exhibited abnormal gallium activity in the lungs, as well as diffuse gallium uptake in the thyroid gland is presented. The latter has not been previously reported and supports the concept of iodide-induced "thyroiditis" with gallium uptake reflecting the inflammatory response.  相似文献   
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Na+ dependence of in vitro pancreatic amylase release   总被引:1,自引:0,他引:1  
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The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to predict optimal procedures for the addition and removal of a cryoprotectant. Simulations were performed using data from four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide, (iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations were applied to determine approaches for the addition and removal of 1 M and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to maintain a cell volume within their osmotic tolerance limits. Based on these data, ethylene glycol was predicted to be optimal for minimizing volume excursions among the solutes evaluated. These predictions were then experimentally tested using glycerol as the control cryoprotectant and ethylene glycol as the experimental cryoprotectant. The results indicate that there was a higher (P < 0.05) recovery of motile spermatozoa after cryopreservation when using 1 M ethylene glycol than with 1 M glycerol, supporting the hypothesis that use of the cryoprotectant for which the cell has the highest permeability will result in higher cell survival.   相似文献   
9.
Use of polyethylene glycol (PEG) to promote adsorption of autoantibodies is reported to give good recovery of concomitant alloantibodies. In initial experiments, PEG and ZZAP (Ficin and DTT) adsorption procedures were compared for removal of autoantibody and recovery of alloantibody. Postadsorption studies (n = 11) were performed and hemagglutination scores compared. In subsequent studies, equal volumes of alloantibody containing sera, PEG, and antigen-negative red blood cells (RBCs) were used in twofold adsorption experiments. Saline was substituted for PEG for control purposes. Postadsorption titers and immunoglobulin levels were determined. Autoantibodies were completely removed by both methods (n = 5); better by PEG (n = 3); better by ZZAP (n = 1); and not adsorbed (n = 1), and partially adsorbed by both (n = 1). Alloantibody recovery was comparable in three cases (E, K, Jka) but weaker by at least one reaction grade in four (K,E, Jka, and antibody to low-frequency antigen). The latter anti-Jka reacted 1+ with Jk(a+b+) RBCs after ZZAP adsorption but was nonreactive with the same RBCs following PEG adsorption. Titers of six alloantibodies adsorbed with antigen-negative RBCs in PEG were markedly weaker (range 2 to 8) compared to saline controls (range 4 to 32). IgG levels for PEG adsorbed (range 128 to 243 mg/dL) were 50% lower than controls (range 265 to 505 mg/dL). Although PEG adsorption is effective in removing autoantibody, the precipitation of immunoglobulin by PEG may result in failure to detect underlying alloantibody.  相似文献   
10.
A total of 447 cervical or vaginal specimens were inoculated in parallel onto peptone-starch-dextrose (PSD) and Columbia colistin (10 mg/ml)-nalidixic acid (15 mug/ml) (CNA) agar and were incubated for 48 h at 35 degrees C in an atmosphere with 2 to 10% CO2. One hundred (22.4%) of the cultures were positive for Haemophilus vaginalis. Forty-eight of the isolates were recovered from both PSD and Columbia CNA agar, five from PSD only, and 47 from Columbia CNA agar only (P less than 0.001). On Columbia CNA agar, 76 of the isolates were detected after 24 h of incubation, and the remainder were detected within 4 days of incubation.  相似文献   
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