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101.
Venous stenoses are the leading cause of dialysis graft and mature dialysis fistula malfunction. We report a simple, inexpensive technique for treating stenoses that are refractory to conventional balloon angioplasty and present a case in which this technique was successfully applied.  相似文献   
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Elevated levels of the mast-cell-associated serum neutrophil chemotactic factor (NCF) and an increase in blood basophil counts were observed in 6 atopic asthmatics during exercise-induced asthma (EIA). These changes were not found when the same degree of airways obstruction was elicited in the same subjects by isocapnic hyperventilation (ISH) with cold air. The NCF was unlikely to be related to the basophilia alone, because asthmatics without EIA who underwent the same exercise task, produced a similar basophilia but significantly less NCF. These findings suggest that mast-cell-associated (as opposed to basophil-associated) mediators of hypersensitivity are detectable in the bloodstream during the bronchoconstriction induced by exercise, but not by ISH.  相似文献   
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Laboratory experiments were carried out to analyze the first valve closure response of a freshwater bivalve (Corbicula fluminea) exposed to uranium during a 5-h period. Experiments were performed in a well-defined artificial water at two pH values, 5.5 and 6.5, with a noninvasive method of valve recording. Sensitivity thresholds, based on percentage of bivalve that close their valves in a given time, were determined. Response thresholds depended on the total uranium concentration, integration time of response (fast responses could only be observed for the highest concentrations), and pH. The bivalve is much more sensitive to total uranium concentration at pH 5.5 than pH 6.5. The minimal sensitivity threshold determined, expressed as the uranium concentration inducing the valve closure of 50% of the bivalves, was 0.05 micromol/L at pH 5.5 after 5 h of exposure. Moreover, higher concentrations of the free ion UO2(2-) are required at pH 5.5 than at pH 6.5 to illicit the same response. Two hypotheses can be proposed, that UO2(2-) is not the only detected species or that competition exists between H- and UO2(2-) for binding sites.  相似文献   
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Anaemia is frequent in breast cancer patients but often remains undiagnosed and untreated. To determine the incidence of anaemia a prospective survey of primary non-metastatic breast cancer patients who received at least four cycles of adjuvant, non-platinum multi-agent chemotherapy was conducted at 47 centres in Austria. Two hundred and forty seven patients were prospectively included between October 1999 and December 1999. Haemoglobin (Hb) levels were determined after surgery and prior to each cycle of chemotherapy. Treatment of anaemia (blood transfusion or epoetin alfa) during the observation period was at the physician's discretion. For the purpose of this study, patients were considered to be anaemic if their Hb was below 12 g/dl. At baseline (after surgery and before the first cycle of chemotherapy), 28.7% of all patients were anaemic. The only significant differentiating factor was the type of surgery. 37.9% of patients who underwent mastectomy were anaemic, whereas only 22.8% of patients who underwent breast conserving surgery were anaemic. Forty two percent of 176 patients with a Hb level of 12 g/dl at baseline developed anaemia during adjuvant chemotherapy. The only factor that significantly influenced the development of anaemia during chemotherapy was the Hb level at baseline. The total incidence of anaemia in patients with primary breast cancer who underwent surgery followed by adjuvant multi-agent chemotherapy was 58.7%. Forty nine patients (20.2%), 48 patients (19.2%) and 48 patients (19.2%) showed a decrease in Hb levels by 1 g/dl, 1–2 g/dl and >2 g/dl, respectively. Only 18.6% of the patients who were found to be anaemic received anaemia treatment. The two most important factors for developing anaemia are the kind of surgery and the Hb level prior to chemotherapy.  相似文献   
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