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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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Na+ dependence of in vitro pancreatic amylase release 总被引:1,自引:0,他引:1
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Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
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
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Summary We have previously shown that specific antibodies (Mab 32/Ab 301) against tumour necrosis factor (TNF) enhance its antiviral activity in vaccinia virus-infected mice. In the present study, TNF alone was found to have antiviral activity against herpes simplex virus-1 (HSV-1). Antibody enhancement was found, both in vivo and in vitro, at lower TNF doses. The magnitude of the TNF-induced antiviral response was dependent upon the genetic background of the mouse. C57BL/6 mice were very sensitive to the antiviral activity of TNF, which was inhibited by the free radical scavenger butylated hydroxyanisole (BHA). TNF plus Mab 32 induced a significant antiviral effect in L929 cells which was associated with pronounced CPE. The CPE was largely reversed in the presence of BHA, and furthermore, TNF antiviral activity was significantly reversed in the presence of BHA. Specific inhibitors of nitric oxide synthetase, lipoxygenase or cyclo-oxygenase did not influence either the CPE or growth kinetics of HSV-1, suggesting that neither reactive nitrogen intermediates nor arachidonic acid metabolites were involved in the antiviral mechanism of TNF. This, together with observed increases in Cu/Zn SOD levels in virus infected cells, suggests that reactive oxygen intermediates may have a role in the direct control of HSV-1 growth and that free radicals may play a part in the antiviral activity induced by TNF. 相似文献
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Comparison of isolation of Haemophilus vaginalis (Corynebacterium vaginale) from peptone-starch-dextrose agar and Columbia colistin-nalidoxic acid agar. 下载免费PDF全文
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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