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991.
STUDY OBJECTIVES: Recurrent chylothorax as a complication of lymphoma has had unsatisfactory outcomes. Serial thoracentesis, tube thoracostomy, and pleurodesis via chest tube have been ineffective and compromise the nutritional and immune status of the patient. Medical thoracoscopic talc pleurodesis has been safe and effective in the treatment of some other varieties of recurrent pleural effusions. Our objective was to investigate the safety and efficacy of medical thoracoscopic talc pleurodesis in the palliation of chylothorax related to lymphoma. DESIGN: This is a report of 24 hemithoraces treated in 19 consecutive patients with lymphoma-related chylothorax, failing chemotherapy or radiation therapy. The average patient age was 55 years. INTERVENTIONS: Medical thoracoscopy was performed under local anesthesia and conscious sedation in a bronchoscopy suite. Sedation included midazolam (mean dose, 6 mg; range, 2-14 mg) with either meperidine (mean dose, 94 mg; range 25-140 mg), or morphine (mean dose, 18 mg; range 4-40 mg). Pleurodesis was performed with insufflation of sterile asbestos-free talc, (4-8 g). After pleurodesis, chest tubes were placed, with the mean duration of chest tube placement being 4 days, range 3 to 10 days. RESULTS: One patient died a few days after the procedure due to causes related to the primary disease process. Follow-up was for at least 90 days following the procedure. Patients were assessed at 30, 60, and 90 days following the procedure. At each of these endpoints, all patients remaining alive were without recurrence of pleural effusions, which was confirmed by chest radiography. Eight patients in the series died of the effects of their malignancy during the 90-day evaluation interval. Complications included medication reactions in two patients (8.3%) and ARDS in one patient (4.1%). CONCLUSION: Many patients with lymphoma-related chylothorax are refractory to chemotherapy and/or radiation therapy. In this group, medical thoracoscopic talc pleurodesis has an acceptable complication rate and a 100% success rate in the prevention of recurrence of pleural effusions at 30, 60, and 90 days following the procedure.  相似文献   
992.
993.
Studies that have shown adverse effects of trans-unsaturated fatty acids on plasma lipoprotein (a) [Lp(a)] levels have used levels of trans-fatty acid that are higher than those in the average U.S. diet. This study was conducted to clarify the effects on Lp(a) of trans-fatty acids levels commonly found in U.S. diets. Lp(a) levels were measured in a double-blind study of 29 men and 29 women who ate 4 controlled diets in random order for 6 weeks each. Fatty acids represented 39% to 40% of energy. The diets were: (1) Oleic (16.7% of energy as oleic acid); (2) Moderate trans (3.8% of energy as trans-monoenes, approximately the trans content of the U.S. diet); (3) High trans (6.6% of energy as trans-monoenes); (4) Saturated (16.2% of energy as lauric plus myristic plus palmitic acids). The Saturated diet lowered Lp(a) levels significantly (by 8% to 11%). Compared to the Oleic diet, the trans diets had no adverse effect on Lp(a) levels when all subjects were considered collectively. A subset with initially high levels of Lp(a) (> or = 30 mg/dL), however, responded to the High trans diet with a slight (5%) increase in Lp(a) levels relative to the Oleic and Moderate trans diets. Thus, in amounts commonly found in the typical U.S. diet, saturated fatty acids consistently decrease Lp(a) concentrations. The adverse effects of replacing cis- with trans-fatty acids are only suggestive and are restricted to high trans intakes in subjects with high Lp(a) levels.  相似文献   
994.
Heterogeneity of the hepatitis B virus (HBV) core gene has been reported to be associated with the presence of active liver disease in Japanese patients with chronic HBV infection. This study evaluated the significance of HBV core gene heterogeneity in Western patients with chronic HBV infection. The hepatitis B virus precore/core gene from 45 patients (inactive:active liver disease ratio 16:29) was amplified from serum by polymerase chain reaction (PCR). Gel electrophoresis was employed to detect large deletions. The PCR amplicons from 13 patients (all HBV serotype adw but with a different spectrum of liver disease) were cloned and sequenced. Hepatitis B surface antigen (HBsAg) serotypes were tested by enzyme immunoassay (EIA) and hepatic expression of HBV antigens was assessed by immunohistochemistry. The HBV core gene was amplified from the serum of all 45 patients. Three patients had mixed infection with both precore mutant and wild-type HBV and all three had active liver disease. No patient had a large deletion of the HBV core gene. Hepatitis B virus core gene sequence variations were more common in the midcore region and there was no difference in the number of silent and missense substitutions between those with inactive and active liver disease. There was no correlation between the nucleotide or encoded amino acid substitutions and the clinical and biochemical parameters, including the subsequent response to interferon-alpha therapy (n = 37) or hepatic HBV antigen expression. Variation of the HBV core gene was not found to be preferentially associated with active liver disease in Western patients with chronic HBV infection. The pattern of hepatitis B core gene variation is in accord with the genomic organization of HBV.  相似文献   
995.
996.
OBJECTIVE: Our purpose was to compare the effects of a new estradiol-releasing vaginal ring with progesterone given as a vaginal suppository, versus the efficacy, safety and acceptability of an intrauterine device releasing levonorgestrel combined with estradiol, delivered transdermally from a patch. Climacteric symptoms, bleeding pattern and endometrial histologic features were studied. METHODS: Fifty six parous, postmenopausal women with urogenital symptoms were allocated in two groups for one year: 28 women receiving estradiol by a vaginal ring and a 100 mg vaginal progesterone suppository 7 days every month and 28 women receiving a continuous transdermal daily dose of 50 micrograms of estradiol with a levonorgestrel-releasing intrauterine device inserted. All the patients were subjected to vaginosonographic examination followed by thorough pathological examination of the uterine curetting samples. RESULTS: A mean endometrial thickness (double layer) of 2.9 and 3.0 mm, respectively, was found to be predictive of normal endometrium. Both treatment regiments effectively relieved climacteric symptoms. Endometrial proliferation was not observed. Spotting was more common in the intrauterine device group than in the vaginal ring group. CONCLUSIONS: Treatment of urogenital symptoms in postmenopausal women with these two forms of hormone replacement therapy is shown to be an effective and safe method, exhibiting advantages over other methods of treatment.  相似文献   
997.
998.
Mosquitoes are infected with Plasmodium falciparum by taking a blood meal from a gametocyte carrier. Since a mosquito takes a volume of 1 to 2 microl, a blood meal may contain 1 x 10(4) to 3 x 10(4) leukocytes (WBC). The majority of WBC are composed of neutrophils which may phagocytose and kill developing gametes inside the mosquito midgut. Phagocytosis was measured in vitro by a luminol-dependent chemiluminescence (CL) assay. In the presence of P. falciparum gametes, sera from areas of endemicity had an increased CL response compared to controls. In mosquito membrane feeding experiments some such sera showed a transmission reduction which was related to the presence of viable WBC. The results of this study suggest that phagocytosis of opsonized gametes inside the mosquito midgut occurs and can contribute to a reduction in the transmission of P. falciparum parasites.  相似文献   
999.
Carotid-jugular arteriovenous fistulas (AVF) are extremely rare with only 20 cases reported in the literature up to December 1996. The case of a 74-year-old man (the oldest reported in the literature) with abnormal communications between the external carotid artery and the internal jugular vein is reported. The condition was treated by platinum coil embolization via catheterization and by repeated operations to ligate the branches of the external carotid artery, besides removal of the tissue containing the fistula and ligation of the external carotid at its origin. The result was incomplete because about 6 months after the last operation the patient showed the same symptoms, although in a milder form. Until standard treatment is established, the appropriate technique should be decided on a patient-to-patient basis.  相似文献   
1000.
Although human myocardial TNFalpha levels are increased during the ischemia associated with chonic heart failure, it remains unknown whether an acute global ischemic insult further increases TNFalpha expression in human cardiac myocytes. To study this, biopsies of human myocardium were obtained before and after cardiopulmonary bypass (in vivo acute global ischemia), and myocardial TNFalpha levels were determined by ELISA and cytotoxicity assay (WEHI-164 clone 13 cell line). TNFalpha was immunolocalized by immunohistochemistry. Results indicate that cardiopulmonary bypass induces an increase in human myocardial TNFalpha by both ELISA and cytotoxicity assays. Immunolocalization revealed that prior to cardiopulmonary bypass TNFalpha was located predominantly in the myocardial interstitial cells; however, following bypass, increased TNFalpha was observed in the cardiocytes themselves. Locally-produced myocardial TNFalpha may be an important contributor to myocardial functional depression and injury following acute ischemia. Targeted anti-TNFalpha therapy in the treatment of cardiac ischemic injury may further elucidate its clinical relevance.  相似文献   
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