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Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
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The aim of this study was to determine whether preoperative physiologic factors can account for and be used to predict the development of postoperative dysphagia after laparoscopic Nissen fundoplication. One hundred sixty-three patients with gastroesophageal reflux disease underwent laparoscopic Nissen fundoplication with a median follow-up of 14 months (range 6 to 81 months). Preoperative dysphagia was present in 37% (60 of 163) and was relieved in all but five patients (92%). Female sex (P = 0.01) and the presence of a stricture (P = 0.02) were the only preoperative variables associated with the presence of preoperative dysphagia. Eight percent (8 of 103) of patients without preoperative dysphagia developed new-onset dysphagia, and of these 63% (5 of 8) had a normal lower esophageal sphincter (LES) (pressure >6 mm Hg; length >2 cm; abdominal length >1 cm). New-onset dysphagia was significantly more common in patients with a normal LES (22% [5 of 23] vs. 4% [3 of 80], P = 001). Patients with a normal LES had almost a sixfold increase in the risk of developing dysphagia as those with an abnormal LES (relative risk = 5.8). Only a preoperative normal LES (P = 0.02) or mean LES pressures (P = 0.04) were positively associated with the development of postoperative dysphagia. The severity of this dysphagia also showed a strong positive trend of increasing with mean preoperative LES pressures (P = 0.07). Finally, preoperative LES pressure significantly correlated with postoperative LES pressure (r = 0.48, P = 0.01) and with mean residual LES (nadir) pressure (r = 0.33, P = 0.05) offering insight into the mechanism of this dysphagia. In conclusion, preoperative LES parameters play a role in the development of dysphagia after laparoscopic Nissen fundoplication. Patients with a normal LES or high mean LES pressures are at increased risk for developing this complication and should be informed of this before laparoscopic Nissen fundoplication. Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Ga., May 20–23, 2001.  相似文献   
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Forty-six (85%) basal cell and eight (15%) squamous cell carcinomas of the eyelids were treated with electron beams between 1963 and 1983. Lesion sizes ranged from microscopic to 4 cm, with 28 lesions larger than 1 cm. Thirty-eight lesions were treated with radiotherapy after incisional biopsy, and 16 were treated after excisional biopsy (specimens showed positive margins). Doses varied from 45 to 72 Gy, with daily fractions ranging from 2.12 to 4.0 Gy. There were six disease recurrences (10.9%): three in the treatment field and three at the treatment margin. Four of six recurrences were subsequently controlled by limited surgical excision and repair with preservation of the eye, whereas the other two required enucleation. Treatment sequelae such as skin atrophy, telangiectasis, and cosmetic results were evaluated in terms of radiotherapy parameters, pretreatment surgery, and size of the lesion. In 44 patients, the overall cosmetic result was judged as good to excellent, five patients had a mild to modest degree of deformity, and five had significant deformity. Such deformity was usually associated with tumor destruction or previous surgery. No major complications were noted.  相似文献   
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The livers of 26 adult males with acquired immune deficiency syndrome (AIDS) were reviewed. The occurrence of portal tracts with diminished lymphocytes, probably reflecting generalized exhaustion of the lymphoid system, was a characteristic morphologic change, and was found in all cases. Kupffer cell hyperplasia was also a frequent finding and probably reflected generalized infection(s). Punched-out clusters of foamy histiocytes filled with acid-fast bacilli, typical for infection with Mycobacterium avium intracellulare (MAC), were found in three patients. In addition, MAC was cultured from two livers without the foamy histiocytic changes. Chronic viral hepatitis (three cases) and deposition of polarizable materials (one case) in the liver might be related to unusual habits of patients with AIDS. In conclusion, livers from patients with AIDS disclosed several kinds of lesions reflecting underlying or associated conditions in AIDS, but these did not contribute to the cause of death in our patients.  相似文献   
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Human liver microsomal bilirubin UDP-glucuronyltransferase catalyzes formation of bilirubin mono- and diglucuronide. KmUDPGA and Vmax of the enzyme are 0.6 mM and 1.69 nmol/mg protein X min. In vitro, bilirubin readily dissolves in the microsomal lipid phase. Taking this into account a Kmbilirubin of 60.6 microM was found, which is much higher than the in vivo microsomal UCB concentration of human liver (2.9-11.4 microM). The total capacity of human liver to form bilirubin mono- and diglucuronide in vitro exceeds the in vivo mono- and diglucuronide production rates by a factor 8 to 10. Radiation-inactivation studies reveal that human liver microsomal bilirubin UDP-glucuronyltransferase is a tetrameric enzyme with a molecular mass of 209 000 +/- 20 000 Da. The complete tetrameric enzyme catalyzes both glucuronidation steps, formation of bilirubin monoglucuronide and conversion of mono- to diglucuronide. In its monomeric form, the enzyme with molecular mass of 55 000 +/- 1 500 Da catalyzes only the first step of bilirubin glucuronidation, the formation of bilirubin monoglucuronide.  相似文献   
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Between January 1966 and August 1981, 159 patients with previously untreated squamous cell carcinomas of the anterior faucial pillar or retromolar trigone received definitive radiation therapy at The University of Texas M. D. Anderson Hospital and Tumor Institute. All except 11 patients were treated by external radiation including combination of electron beams with high-energy photons or 60Co to doses ranging from 60 Gy to 75 Gy. In the N0 patients, as a rule, only the ipsilateral subdigastric nodes were treated electively to a dose of 50 Gy. The 5-year determinate survival rate for the overall group was 83%. The cumulative recurrence rate showed that 92% of the patients had recurrence by 2 years. Therefore, all patients except those who died with no evidence of local disease less than 2 years after treatment were evaluated for local control. The failure rate for the evaluable patients was 29% for T1 lesions, 30% for T2 lesions, 24% for T3 lesions, and 40% for T4 lesions. After salvage surgery, which consisted of intraoral resection in one-third of the patients and of a composite operation in the other two-thirds, the ultimate failure rate was 0% for T1 lesions, 6% for T2 lesions, 8% for T3 lesions, and 20% for T4 lesions. Whereas stage was a poor indicator for treatment outcome, there was a significantly higher failure rate for infiltrative and/or ulcerated lesions (35%) than for exophytic or superficial lesions (15%). Histologic grade was of no prognostic significance, nor was there any significant difference in the failure rate for lesions originating on the anterior faucial pillar versus that for lesions on the retromolar trigone. Following radiotherapy, 30% of the patients developed some degree of bone exposure but only 5.6% (9 patients) required a segmental mandibular resection. The probability of bone exposure was not dose related and more likely reflected tumor location on the mucoperiosteum. Of the whole group, 16 patients (10%) experienced a neck failure with 8 ultimate failures after salvage surgery. Among the 16 patients who had neck failures, 13 were originally staged N0; 6 of these patients had failures that occurred in the electively treated ipsilateral subdigastric area, but the field was too small to cover the nodes adequately. Aspects of the radiotherapy techniques with combined electron and photon beams that may influence the treatment outcome are discussed.  相似文献   
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Background: Postoperative nausea and vomiting (PONV) is a distressing problem after strabismus surgery. An inspired oxygen fraction has been reported to decrease PONV in patients after colon resection and to be more effective than ondansetron after gynecologic laparoscopy. Therefore, in a randomized, prospective, placebo-controlled study, the authors tested whether an inspired oxygen fraction of 0.8 decreases PONV in patients undergoing strabismus surgery and whether oxygen is more effective than ondansetron.

Methods: With approval of the authors' institutional review board, 210 patients were randomly assigned to receive one of three treatments: (1) 30% inspired oxygen in air plus intravenous administration of saline, (2) 80% inspired oxygen in air plus intravenous administration of saline, or (3) 30% inspired oxygen in air plus 75 [mu]g/kg ondansetron intravenously during induction. General anesthesia was standardized and included etomidate, alfentanil, and mivacurium for induction and sevoflurane for maintenance. PONV was evaluated 6 and 24 h postoperatively by an investigator unaware of treatment assignment.

Results: Overall postoperative incidence of nausea and vomiting was 41% for inspired oxygen fraction of 0.3 plus placebo, 38% for inspired oxygen fraction of 0.8 plus placebo, and 28% for inspired oxygen fraction of 0.3 plus ondansetron, respectively (P = 0.279). Therefore, there was no statistically significant difference of PONV incidence among groups.  相似文献   

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