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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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Hong HH Devereux TR Melnick RL Moomaw CR Boorman GA Sills RC 《Toxicologic pathology》2000,28(4):529-534
1,3-Butadiene is a multisite carcinogen in rodents. Incidences of cardiac hemangiosarcomas were significantly increased in male and female B6C3F1 mice that inhaled 1,3-butadiene (BD) for 2 years. Eleven BD-induced cardiac hemangiosarcomas were examined for genetic alterations in ras protooncogenes and in the p53 tumor suppressor gene. Nine of 11 (82%) BD-induced hemangiosarcomas had K-ras mutations and 5 of 11 (46%) had H-ras mutations. All of the K-ras mutations were G-->C transversions (GGC-->CGC) at codon 13; this pattern is consistent with reported results in BD-induced lung neoplasms and lymphomas. Both K-ras codon 13 CGC mutations and H-ras codon 61 CGA mutations were detected in 5 of 9 (56%) hemangiosarcomas. The 11 hemangiosarcomas stained positive for p53 protein by immunohistochemistry and were analyzed for p53 mutations using cycle sequencing of polymerase chain reaction (PCR) amplified DNA isolated from paraffin-embedded sections. Mutations in exons 5 to 8 of the p53 gene were identified in 5 of 11 (46%) hemangiosarcomas, and all of these were from the 200- or 625-ppm exposure groups that also had K-ras codon 13 CGC mutations. Our data indicate that K-ras, H-ras, and p53 mutations in these hemangiosarcomas most likely occurred as a result of the genotoxic effects of BD and that these mutations may play a role in the pathogenesis of BD-induced cardiac hemangiosarcomas in the B6C3F1 mouse. 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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Sills RC Morgan DL Herr DW Little PB George NM Ton TV Love NE Maronpot RR Johnson GA 《Toxicologic pathology》2004,32(5):501-510
In this carbonyl sulfide (COS) study, magnetic resonance microscopy (MRM) and detailed light microscopic evaluation effectively functioned in parallel to assure that the distribution and degree of pathology in the brain was accurately represented. MRM is a powerful imaging modality that allows for excellent identification of neuroanatomical structures coupled with the ability to acquire 200 or more cross-sectional images of the brain, and the ability to display them in multiple planes. F344 rats were exposed to 200-600 ppm COS for up to 12 weeks. Prior to MRM, rats were anesthetized and cardiac perfused with McDowell Trump's fixative containing a gadolinium MR contrast medium. Fixed specimens were scanned at the Duke Center for In Vivo Microscopy on a 9.4 Tesla magnetic resonance system adapted explicitly for microscopic imaging. An advantage of MRM in this study was the ability to identify lesions in rats that appeared clinically normal prior to sacrifice and the opportunity to identify lesions in areas of the brain which would not be included in conventional studies. Other advantages include the ability to examine the brain in multiple planes (transverse, dorsal, sagittal) and obtain and save the MRM images in a digital format that allows for postexperimental data processing and manipulation. MRM images were correlated with neuroanatomical and neuropathological findings. All suspected MRM images were compared to corresponding H&E slides. An important aspect of this study was that MRM was critical in defining our strategy for sectioning the brain, and for designing mechanistic studies (cytochrome oxidase evaluations) and functional assessments (electrophysiology studies) on specifically targeted anatomical sites following COS exposure. 相似文献
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