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991.
OBJECTIVE: To assess the efficacy of partial left ventriculectomy as a treatment for patients with end-stage heart failure. METHODS: From February to June 1995, 7 patients with end-stage heart failure underwent partial left ventriculectomy. Subsequently, patients underwent clinical evaluation every 2 months, and 2-dimensional echocardiography at the 6th and 12th months after cardiac surgery. All patients were given digitalis and diuretics at conventional doses, and captopril or enalapril at maximal tolerated doses. RESULTS: Two (28%) patients died; 1 from cardiac arrhythmia associated with gastrointestinal hemorrhage, and the other suddenly. One (14%) patient developed an embolic cerebrovascular accident. Four (57%) patients were hospitalized for congestive heart failure; all of them had either decreased the daily dose of captopril or enalapril or discontinued the drugs by themselves. Twelve months after ventriculectomy, left ventricular ejection fraction values were greater and left ventricular diastolic dimension and functional class values lower than those found before cardiac operation. CONCLUSION: Beneficial effects of partial left ventriculectomy are observed one year after the surgical procedure. This technique, therefore, can be useful for the treatment of patients with end-stage heart failure. 相似文献
992.
AS Baur G Sass B Laffert D Willbold C Cheng-Mayer BM Peterlin 《Canadian Metallurgical Quarterly》1997,6(3):283-291
A multi-center case-referent study was conducted on the relation between paternal occupational exposure and spina bifida in offspring. Cases were born between 1980 and 1992 in The Netherlands. Referents were recruited from hospitals and from the general population. Postal questionnaires were used to gather information on occupation and potential confounders. Through job-specific telephone interviews with 122 case fathers and 411 referent fathers, detailed exposure information was collected on specific tasks, the use of chemical or physical agents, frequency of exposure, and use of protective equipment. The study yielded statistically significant associations between spina bifida and low exposure to welding fumes (OR = 1.6, 95% CI: 1.0-2.6) and low exposure to UV radiation during welding (OR = 2.6, 95% CI: 1.2-5.6), and suggestive findings of an association between spina bifida and moderate or high exposure to cleaning agents, moderate or high pesticide exposure (OR = 1.7, 95% CI: 0.7-4.0), and stainless steel dust (OR = 2.0, 95% CI: 0.8-5.2). No associations were identified for other paternal occupational exposures, such as organic solvents. 相似文献
993.
R Shrestha JD Durham M Wachs BM Bilir I Kam T Trouillot GT Everson 《Canadian Metallurgical Quarterly》1997,92(12):2304-2306
We report a case of fulminant hepatic failure in a 55-yr-old man due to Budd-Chiari syndrome in the setting of polycythemia rubra vera. The patient presented with acute hepatic failure, which rapidly progressed to grade IV hepatic encephalopathy. Placement of a transjugular intrahepatic portosystemic shunt resulted in marked improvement of the encephalopathy and stabilized the liver failure. Subsequently, he underwent successful nonemergent orthotopic liver transplantation. Transjugular intrahepatic portosystemic shunt placement is a safe, effective, therapeutic option to bridge patients with fulminant Budd-Chiari to liver transplantation. 相似文献
994.
Antibiotic-associated diarrhea (AAD) is a common complication of antibiotics and recent findings on the epidemiology, etiologies and treatment strategies are reviewed. Rates of AAD vary from 5 to 39% depending upon the specific type of antibiotic. The severity of AAD may include uncomplicated diarrhea, colitis or pseudomembranous colitis. The pathogenesis of AAD may be mediated through the disruption of the normal flora and overgrowth of pathogens or through metabolic imbalances. The impact of AAD is reflected by increased hospital stays, higher medical costs and increased rates of comorbidity. The key to decreasing these consequences is prompt diagnosis followed by effective treatment and institution of control measures. 相似文献
995.
MJ Millward LK Webster D Rischin KH Stokes GC Toner JF Bishop IN Olver BM Linahan ME Linsenmeyer DM Woodcock 《Canadian Metallurgical Quarterly》1998,4(10):2321-2329
Cremophor EL (cremophor), a component of the paclitaxel formulation, can potentially reverse P-glycoprotein-associated multidrug resistance. A Phase I trial of cremophor as a 6-h infusion every 3 weeks was performed with bolus doxorubicin (50 mg/m2). The cremophor dose was escalated from 1 to 60 ml/m2. A standard paclitaxel premedication was given before cremophor. Using a bioassay, potentially active cremophor levels (> or = 1 microl/ml) were measured in plasma from patients receiving cremophor doses of 30, 45, and 60 ml/m2. A cross-over design was used to assess the influence of cremophor 30 ml/m2 on the pharmacokinetics of doxorubicin and doxorubicinol. The plasma area under the concentration versus time curve (AUC) of doxorubicin increased from 1448 +/- 350 to 1786 +/- 264 ng/ml x h (P = 0.02) in the presence of cremophor, whereas the AUC of doxorubicinol increased from 252 +/- 104 to 486 +/- 107 ng/ml x h (P = 0.02). This pharmacokinetic interaction was associated with significantly increased neutropenia. With reduction of the doxorubicin dose to 35 mg/m2, the cremophor dose was increased to 60 ml/m2. Dose-limiting toxicities occurred in two of six patients after 45 ml/m2 and two of four patients after 60 ml/m2, which included febrile neutropenia and grade III cremophor-related toxicities of rash, pruritus, headache, and hypotension. All patients who received 45 ml/m2 cremophor reached plasma levels > or = 1.5 microl/ml, but at 60 ml/m2, only two of four reached this level, and the calculated plasma clearance of cremophor was significantly faster at this dose. One patient with hepatoma resistant to epirubicin achieved a near-complete response. Cremophor 45 ml/m2 over 6 h with 35 mg/m2 doxorubicin is recommended for further studies. The pharmacokinetic interaction between cremophor and doxorubicin is quantitatively similar to that described in trials of paclitaxel with doxorubicin and suggests that the cremophor in the paclitaxel formulation is responsible. 相似文献
996.
BM Eley 《Canadian Metallurgical Quarterly》1997,182(7):247-249
This is the first article in a series of seven on the future of dental amalgam. Dental amalgam is still the most useful restorative material for posterior teeth and has been used successfully for over 100 years. The history of dental amalgam since its introduction in 1819 and the controversies about its use between 1834 and today are described. The composition of the various dental amalgams in clinical use today are then reported. It finally covers the corrosion of amalgams since this is the means by which metals, including mercury, can be released. 相似文献
997.
BM Dickens 《Canadian Metallurgical Quarterly》1997,16(4):687-703
The diagnosis and treatment of adnexal cancers continues to pose a challenge to a wide range of clinicians. The diseases are a diverse lot, owing to the wide range of skin structures and large surface area. Early recognition and treatment are key to improved outcomes. Education of the patients as to their role in their care, especially early detection, is also of crucial importance. Further study may yield information to improve diagnosis and treatment. 相似文献
998.
BC Cahill JR Hibbs K Savik BA Juni BM Dosland C Edin-Stibbe MI Hertz 《Canadian Metallurgical Quarterly》1997,112(5):1160-1164
To assess the effect of hemolysis on serum retinol concentrations determined by direct fluorometry, we assayed 196 blood samples from children 6-72-mo of age with various grades of hemolysis for serum retinol by both fluorescence and HPLC. Mean serum retinol concentrations determined by HPLC did not differ significantly according to hemolysis grade; however, fluorometric values did. Additionally, serum retinol concentrations obtained from HPLC and those obtained from direct fluorometry were significantly different in samples with severe hemolysis. Multivariate-regression analysis showed that hemolysis grade was a significant predictor of the difference in mean serum retinol values determined by the two methods. Although severe hemolysis interfered with determinations of serum retinol by direct fluorometry, this method is still a viable choice for field studies of vitamin A status. 相似文献
999.
Nonspecific IgE binding to allergens was observed in testing myeloma IgEs, namely, IgE-VL and IgE-PS, chimeric IgE (IgE-JW8), and the recombinant IgE Fc epsilon peptide CH1-CH4, in two different immunoassays. This binding was concentration-dependent but detectable only at higher IgE concentration. In RAST inhibition, IgE-allergen interactions could be reduced by using either matching or nonmatching allergens. In order to test whether the nonspecific binding of IgE to allergens was due to carbohydrate interaction, myeloma IgEs and the chimeric IgE were desialized with neuraminidase. Desialized samples were equally well recognized by xenogenic antibodies as native IgEs, but binding of IgE to Fc epsilon receptors on basophils was affected by the treatment, as shown in the histamine-release assay. Desialization of IgE affected also its binding capacity to allergens in RAST: binding of chimeric IgE was reduced, but nonspecific binding of myeloma IgE-VL was enhanced. Hence, nonspecific allergen-IgE binding may be partly due to a lectin-like interaction, but may depend mostly on the tertiary structure of IgE. Thus, nonspecific IgE-allergen interactions might present a problem 1) at high IgE concentration, and 2) depend on the grade of sialization of IgE, which might affect its conformation. This may explain why patients with elevated total IgE levels often have multiple weak positive RASTs with non-cross-reactive allergens. 相似文献
1000.
The role of chemotherapy in malignant neuroendocrine tumours is difficult to assess because of their rarity and variation in biological behaviour. We present a retrospective review of chemotherapy given to 18 patients with metastatic and one with locally advanced neuroendocrine tumours. There were eight poorly differentiated neuroendocrine tumours, six thyroid medullary carcinomas, two phaeochromocytomas, two pancreatic islet cell tumours and one undifferentiated neuroblastoma. Four patients were given 3-weekly dacarbazine, vincristine and cyclophosphamide (DOC) chemotherapy. In eight patients, this regimen was modified by substituting the dacarbazine and cisplatin and etoposide (OPEC). A further six patients were treated with dacarbazine reintroduced into the 3-weekly regimen (DOPEC). The remaining patient received cisplatin and etoposide. There were two complete responses (both with OPEC) and eight partial responses (two with DOC, three with OPEC and three with DOPEC). Five patients had stable disease and four progressed. Four received further chemotherapy on relapse, producing one complete and one partial response. The median response duration to initial chemotherapy was 10 months (range 3-34). The median survival was 12 months (range 1-42). The main toxicity was haematological, with grade 3-4 neutropenia in 12 patients; eight suffered episodes of sepsis. One death was treatment related. Other toxicity was mild although three patients discontinued vincristine with grade 2 neurotoxicity. The response rate and side effects of these three regimens appear comparable. We conclude that, although these patient numbers are small, combination chemotherapy produces an encouraging response rate (53%; 95% CI 30-75) in malignant neuroendocrine tumours, with acceptable toxicity. 相似文献