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131.
The recently developed ELISA for the thrombin-antithrombin III complex (TAT) is a sensitive, specific, and simplified means of detecting intravascular coagulation. For further evaluation of the thrombogenicity of a polyamide (P) and a Hemophan (H) hollow-fibre dialyzer a cross-over study was done in ten stable patients on maintenance hemodialysis. At the same doses of heparin (mean bolus of 30 U/kg bw and maintenance doses of 86 U/kg bw), thrombin time and partial thromboplastin time were significantly lower using H. At the end of dialysis TAT was significantly higher in H (mean +/- SEM before HD 3.57 +/- .56, at 240 min 14.9 +/- 6.5 ng/ml, p less than 0.05, Wilcoxon-test) than in P (before HD 4.36 +/- .98, at 240 min 8.95 +/- 3.0 ng/ml, p less than 0.05 H 240 vs. P 240, Wilcoxon-test). Visible clotting was more pronounced in the H filter. Among other favourable features of blood compatibility the polyamide/polyvinylpyrrolidone copolymer with a hydrophilic/hydrophobic microdomain structure has less thrombogenicity. The modified cellulosic membrane H has advantages in complement activation and leukocyte depression, but thrombogenicity seems less favourable since the incorporated diethyl-amino-ethyl groups with their positive charge bind and inactivate negatively charged heparin.  相似文献   
132.
Although malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma of adult life, it is fairly rare in the head and neck region (3-6%). Between 1983 and 1991 8 patients with MFH in the head and neck region have been observed and treated at the ENT-department of the University of Tübingen. 5 patients have been operated (laryngopharyngeal localization), 2 patients underwent irradiation (unresectable fast growing T4-tumors of the pharynx and thyroid) and one female patient refused further therapy after two resections elsewhere. Operated patients showed no evidence of disease 2-8 years after resection (all margins have been controlled histologically). Both irradiated patients died 4 respectively 2 months after full (70 Gy) and incomplete (17 Gy) radiotherapy without visible positive effects. Both patients developed pulmonary metastasis. Since MFH can grow in thin layers along musculaoponeurotic structures the exact size is not always demonstrable by ultrasound, CT or MR scans. Metastasis occur in up to 40%, preferentially in regionary lymph nodes, in lung, liver and skeletal system. These phenomenon requires a full pretherapeutic staging. Histologically MFH is sometimes hard to distinguish from other tumors as for example various sarcomas and pleomorphic carcinoma. Therefore, immunohistochemical (mesenchymal markers) and electron microscopical investigations are advised. Resection with exact histological controll of all margins is the therapy of choice. We experienced that laryngeal MFH (n = 3) can be resected without laryngectomy under certain circumstances. Although unsuccessfull in our two cases, according to the literature, radiotherapy should be administered in unresectable cases. Depending on localization and size of MFH long survival, in single cases healing, of this disease is possible by surgical treatment.  相似文献   
133.
A case illustrating the potentially fatal complication of endogenous Gram Negative Aerobic Bacillus (GNAB) septicaemia secondary to nosocomial pneumonia is presented along with current theories as to its aetiology. The technique of selective decontamination of the digestive tract is designed and advocated to prevent such occurrences; oral and maxillofacial surgeons should be aware of this approach. It may be, however, that by using much simpler manoeuvres such as changes in policy regarding gastric stress ulcer prophylaxis, the already small risk of such an occurrence will be further reduced. Awareness of this condition will allow a higher index of suspicion when presented with catastrophic septic complications on the ITU and aid in more rational planning of antimicrobial therapy.  相似文献   
134.
In 41 patients with recurrent sustained ventricular tachycardia and/or ventricular fibrillation an integrated pacemaker-defibrillator-system (PCD, Medtronic, model 7216 A or 7217 B) was implanted. In 21 out of 24 (88%) patients a new transvenous implantation technique in combination with a subcutaneous patch electrode was used. The implanted devices comprise antibradycardiac pacemaker functions, two different forms of antitachycardiac pacemaker functions (ramp and burst pacing), and internal cardioversion or defibrillation capabilities. During a mean follow-up of 8 months 147 episodes of ventricular tachycardia were detected, 131 of them were terminated successfully by antitachycardiac pacing; in 13 episodes internal cardioversion was applied to revert ventricular tachycardia. Twenty-seven episodes of ventricular fibrillation or rapid ventricular tachycardia (greater than 200/min) were detected and successfully terminated by internal defibrillation. In six patients with intermittent rapid atrial fibrillation, change of antiarrhythmic therapy was required to avoid activation of the device. The new integrated pacemaker-defibrillator systems improve therapy in patients with life-threatening tachyarrhythmias by reducing the number of internal cardioversions/defibrillations; the non-thoracotomy approach reduces the post operative risk.  相似文献   
135.
Of 431 patients with gastric cancer observed in our institution, 23 (5.3%) had early gastric cancer (EGC). Macroscopic presentation, histology, depth of invasion, and lymph node involvement were evaluated in all the cases. All patients underwent surgery and an intensive follow-up was performed. Five of the 23 patients progressed, and the risk factors were examined. Histology seemed to be the main prognostic factor in our study, since intestinal type of EGC was associated to a significantly better prognosis. Total gastrectomy is indicated in the proximal localization of EGC, and should perhaps be performed also in cases presenting undifferentiated histology.  相似文献   
136.
The anticarcinogenic action of the garlic constituent diallyl sulfide (DAS), was examined in the hamster buccal pouch and forestomach. Groups of hamsters were topically treated, for up to 14 weeks, with a 0.5% solution of the buccal pouch and forestomach carcinogen 7,12-dimethylbenz[a]anthracene (DMBA). Prior to, during and after DMBA treatment, groups of hamsters were also treated, on alternate days, with a 1% solution of DAS. In addition to tumor formation, the induction of gamma-glutamyl transpeptidase (gamma GT) buccal pouch epithelial lesions served as an additional presumptive index of in vivo carcinogenesis/anticarcinogenesis. DAS resulted in a significant reduction in buccal pouch tumor frequency, buccal pouch tumor burden, buccal pouch gamma GT lesion frequency and forestomach tumor frequency. In a separate experiment, DAS also reduced the level of autoradiographically quantified unscheduled DNA repair synthesis (UDS) in pieces of hamster buccal pouch concurrently exposed in vitro to the potent buccal pouch carcinogen N-methyl-N-benzylnitrosamine (MBN). This study demonstrates that DAS is an effective anticarcinogenic agent in squamous mucosa of the hamster and suggests novel cost-effective strategies for the rapid identification of tissue-specific anticarcinogens and a quantitative assessment of their efficacy.  相似文献   
137.
The essential features of treatment for chemical sensitivity are: 1) Encouraging the provision of clean air, food, water, and surroundings. 2) Identifying substances to which the patient is sensitive, with subsequent a) enhanced avoidance, or b) specific immunotherapy to reduce the patient's reactivity to those substances. 3) Assessing and enhancing the patient's nutritional status to maximize the body's ability to detoxify and to minimize the free-radical production and oxidative stress of xenobiotics. 4) Addressing concurrent problems such as infections, immunosuppression, and other medical conditions in an appropriate fashion. 5) Evaluating the patient's psychologic status and addressing any social and emotional problems in a compassionate manner. The author believes that multiple chemical sensitivity is a real condition with documented physiologic abnormalities. It is not a functional or psychologic illness or a belief system of the patient. Second, this condition is diagnosable and treatable by various means. These treatment options not only make common sense but usually result in significant improvement for these unfortunate patients, who deserve the very best efforts of their health care providers.  相似文献   
138.
Exposure to cadmium via the diet is known to depend to a large extent on the intake of cereal grains, particularly the high-fibre fractions of wheat. Subjects with low iron status absorb more cadmium than those with better iron status. The purpose of the present study was to determine to what extent cadmium accumulation in human placenta is affected by the intake of grain fibre and maternal iron status during pregnancy. Thirty-nine pregnant women participated in the study. In each trimester the women were requested to complete a dietary history and to allow blood samples to be taken for haemoglobin, serum ferritin and serum thiocyanate determinations, the latter as a marker for smoking. At delivery the whole placenta was taken for the determination of the cadmium concentration. The 32 women who had serum thiocyanate levels less than 70 mumol/l, who had completed at least one dietary history and from whom a blood sample was obtained in the third trimester, were included in the final statistical analyses. In the group of women who consumed less than the median intake of grain fibre and had more than 15 micrograms ferritin/l serum in the third trimester, the placenta cadmium concentration was nearly half that in the placentae of women who had consumed more grain fibre or had lower iron status in late pregnancy.  相似文献   
139.
Premalignant lesions of the penis include cutaneous horn, balanitis xerotica obliterans, and leukoplakia. The true incidence of progression of each of these to squamous-cell carcinoma is unknown. Bowenoid papulosis, erythroplasia of Queyrat, and Bowen's disease are histologically identical to in situ carcinoma. Although the first is consistently benign, the latter two regularly evolve into invasive cancer. Malignant scrotal lesions include squamous-cell carcinoma, liposarcoma, leiomyosarcoma, basal-cell carcinoma, extramammary Paget's disease, erythroplasia of Queyrat, malignant melanoma, and metastases. Hemangioma can be confused with carcinoma.  相似文献   
140.
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