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991.
B Hynes J B Boyd P J Gullane R T Manktelow L E Rotstein 《Canadian journal of surgery》1987,30(6):436-439
The free jejunal graft with microvascular anastomosis offers the head and neck surgeon a reliable, single-stage method of repair for small cervical defects and also for more extensive pharyngoesophageal defects where one or more loops of jejunum can successfully be used. If microvascular expertise is available, this method of reconstruction offers early alimentary rehabilitation and a physiologic repair. The free jejunal graft is a reliable method of reconstruction not only after failed gastric pull-up or when that procedure is not feasible, but also, where the facilities exist, as a primary method of pharyngoesophageal reconstruction. 相似文献
992.
993.
To ensure effective antimicrobial or tumouricidal function, phagocytic cells must maintain their cytoplasmic pH (pHi) at a level conductive to optimal intracellular enzyme activity. The mechanisms by which neutrophils and macrophages regulate their cytoplasmic pH include bicarbonate-independent ion transport systems, most notably the Na+/H+ exchanger, and bicarbonate-dependent ion transport systems, which can be subdivided into the cation-independent and Na(+)-dependent forms of chloride/bicarbonate exchange. In addition, macrophages have been shown to recover from intracellular acid loading by means of an ATP-dependent proton extrusion mechanism, which has the characteristics of a vacuolar-type H+ ATPase. In the microenvironment typically associated with abscesses, the low extracellular pH and the presence of short chain fatty acid by-products of bacterial metabolism tend to induce cytoplasmic acid loading. In this setting, the ability of the various pHi regulatory mechanisms to protect pHi may be overcome, leading to cytoplasmic acidification. Several investigators have shown that cytoplasmic acidification impairs the ability of neutrophils to migrate in response to chemotactic stimuli, and also impairs their ability to generate a respiratory burst, thus inhibiting the release of toxic oxygen radicals. This may result in the inability of phagocytes to effect complete abscess resolution. 相似文献
994.
The relationship between hormone receptor content and the effect of adjuvant tamoxifen in operable breast cancer 总被引:2,自引:0,他引:2
L E Rutqvist B Cedermark T Fornander U Glas H Johansson B Nordenskj?ld S Rotstein L Skoog A Somell T Theve 《Journal of clinical oncology》1989,7(10):1474-1484
The relationship between hormone receptor status and the effect of adjuvant tamoxifen in early breast cancer remains controversial. This article presents the results of a randomized trial of adjuvant tamoxifen (40 mg daily for 2 years) versus no adjuvant endocrine therapy in postmenopausal patients. During 1976 to 1984, 1,407 patients were included in the study. Of these, 427 (30%) had high-risk tumors (pN + or pT greater than 30 mm) and were included in a concurrent randomized comparison of postoperative radiotherapy versus adjuvant polychemotherapy. The mean follow-up time was 61/2 years. Tamoxifen improved the recurrence-free survival (RFS) (P less than .01), but the overall survival difference in favor of the tamoxifen-allocated patients was not significant. Data on estrogen (ER) and progesterone receptor (PgR) content were available in 750 patients. Their mean follow-up time was 41/2 years. The effect of tamoxifen was significantly related to ER level (P less than .01). No benefit with tamoxifen was observed among ER-negative patients. The relation to PgR level was of borderline significance (P = .06). Multivariate analysis indicated that most of the interaction between treatment and receptor content was explained by the interaction with ER (P less than .01). The PgR status appeared to modify the effect of tamoxifen among the ER-positive patients and the greatest effect was observed among patients who were positive for both receptors. However, the additional predictive information provided by the PgR assay did not help to identify an unresponsive subgroup of patients. 相似文献
995.
L E Rutqvist B Cedermark U Glas H Johansson S Rotstein L Skoog A Somell T Theve N Wilking J Askergren 《Acta oncologica (Stockholm, Sweden)》1992,31(2):265-270
The paper presents long-term results of a randomized trial of adjuvant tamoxifen (40 mg daily for 2 or 5 years) versus surgery alone including 1,347 postmenopausal patients with histologically negative axillary nodes and a tumour diameter less than or equal to 30 mm. Data on the estrogen receptor status of the primary tumour were available in 1,136 patients (84%). At a median follow-up of 7 years (range 1.7-13.0 years) there was a significant prolongation of the recurrence-free survival among those allocated to tamoxifen (p less than 0.01), significantly fewer deaths due to breast cancer (p = 0.02) and a trend towards improved overall survival (p = 0.11). The treatment benefit was restricted to patients with ER-positive tumours. There was no significant reduction of breast cancer recurrences in the tamoxifen group among patients whose tumours were classified as ER-negative. The results support and extend previous studies in showing a long-term benefit of tamoxifen in postmenopausal breast cancer patients with node-negative, estrogen receptor positive disease. 相似文献
996.
Duodenojejunostomy and stapled occlusion for distal duodenal perforation from malignant retroperitoneal tumors 总被引:1,自引:0,他引:1
Three patients with unresectable malignant retroperitoneal tumors that invaded and perforated the distal duodenum presented with sepsis unresponsive to antibiotics. A technique of proximal side-to-side duodenojejunostomy with stapled occlusion of the distal duodenum resulted in successful diversion and immediate resolution of sepsis. 相似文献
997.
Antimicrobial prophylaxis in surgery. Committee on Antimicrobial Agents, Canadian Infectious Disease Society. 总被引:2,自引:0,他引:2 下载免费PDF全文
OBJECTIVE: To provide guidelines for antimicrobial prophylaxis on the basis of the type of surgical procedure. OPTIONS: Standard drug regimens for prophylaxis of infection in a variety of surgical procedures were considered, including a first-generation cephalosporin; an aminoglycoside in combination with metronidazole, clindamycin or erythromycin; a second-generation cephalosporin; and trimethoprim-sulfamethoxazole. OUTCOMES: In order of importance: efficacy, side effects and cost. EVIDENCE: A MEDLINE search of articles published between January 1980 and December 1991. For clinical trial data, greatest emphasis was placed on randomized, double-blind studies using appropriate controls. VALUES: The Committee on Antimicrobial Agents of the Canadian Infectious Disease Society (CIDS) and two recognized experts (T.K.W. and O.D.R.) recommended antimicrobial regimens suitable for prophylaxis of infections in surgery. Whenever possible, recommendations were based on data from randomized controlled trials. BENEFITS, HARMS AND COSTS: Implementation of the guidelines is expected to reduce the incidence of postoperative infections, the inappropriate use of antibiotics and costs to hospitals. RECOMMENDATIONS: Antibiotic prophylaxis is recommended for operations with a high risk of postoperative wound infection or with a low risk of infection but significant consequences if infection occurs. These operations include clean-contaminated procedures and certain clean procedures. Drugs should be administered intravenously immediately before the operation. In colorectal operations oral administration also appears to be effective. A single dose is sufficient for most procedures. The regimen chosen depends on the pathogens usually associated with wound infection in a given operation, the serum half-life of the drugs, the antimicrobial susceptibility patterns in the local hospital and the cost of the drugs. VALIDATION: The guidelines were compared with others in standard textbooks of surgery and peer-reviewed articles. The guidelines were prepared and revised by the Committee on Antimicrobial Agents of the CIDS. They were then reviewed and revised further by the Council of the CIDS. SPONSOR: The CIDS was solely responsible for developing, funding and endorsing these guidelines. 相似文献
998.
C L Wells O D Rotstein T L Pruett R L Simmons 《Archives of surgery (Chicago, Ill. : 1960)》1986,121(1):102-107
Experimental intra-abdominal abscesses were initiated by surgical implantation of a fibrin clot contaminated with either Bacteroides fragilis, Bacteroides thetaiotaomicron, or B fragilis-Escherichia coli. Seven days after surgery the numbers of bacteroides (per gram) in B fragilis and B thetaiotaomicron abscesses were typically log10 8.4 +/- 0.5 (n = 6) and log10 6.4 +/- 0.6 (n = 4), respectively; B fragilis-E coli abscesses typically contained log10 8.9 +/- 0.5 B fragilis and log10 7.6 +/- 0.6 E coli (n = 5). Of 38 B fragilis abscesses, 14 B fragilis-E coli abscesses, and nine B thetaiotaomicron abscesses, additional intestinal bacteria were recovered from 21 (55%), 13 (93%), and seven (89%) abscesses, respectively. The additional organisms, in decreasing order of frequency, were enterococci, E coli, staphylococci, alpha-streptococci, lactobacilli, and Proteus species in numbers ranging from 2.5 log10 to 7.9 log10 per gram of abscess. Histologic sections of contaminated abscesses adherent to the intestine, liver, or spleen revealed normal tissue histology and no breakdown of the abscess wall. Thus, intestinal bacteria translocated into intra-abdominal abscesses by a mechanism that did not appear to be surgical soilage. 相似文献
999.
A phase I dose escalation trial of yttrium-90 microspheres in the treatment of primary hepatocellular carcinoma. 总被引:11,自引:0,他引:11
METHODS. Ten patients with primary hepatocellular carcinoma were treated with intraarterial instillation of yttrium-90 (Y-90) microspheres, including eight men and two women (median age, 52 years; range, 29-69 years). Four patients were treated at a targeted hepatic dose of 50 Gy, two at 75 Gy, and four at 100 Gy. RESULTS. In 8 of the 10 patients, there was a significant concentration of Y-90 in localized tumor masses with tumor-to-liver perfusion ratios from 1.0:1-10.0:1. No patient had a complete or partial response, but 10 patients had stable disease (median duration, 10 weeks; range, 5-64 weeks). The median survival was 18 weeks (range, 2-150 weeks), and three patients lived longer than 1 year. Significant bone marrow or hepatic toxicity was not seen. One patient had a radiation-induced duodenal ulcer that required surgical management. CONCLUSIONS. Intraarterial instillation of Y-90 microspheres appears to be safe and deserves additional evaluation to determine whether there is meaningful activity in patients with primary hepatocellular carcinoma. 相似文献
1000.