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881.
We describe an improved synthesis and properties of fluphenazine-mustard, a potent phenothiazine having an alkylating chlorethylamine chain in its structure. The drug possesses anticalmodulin activity equivalent to the parent compound, but unlike fluphenazine dihydrochloride, the mustard derivative irreversibly antagonizes the ability of calmodulin to activate cyclic nucleotide phosphodiesterase. This property is partially calcium-dependent and can be overcome by coincubation with excess fluphenazine dihydrochloride. The compound irreversibly inactivated calmodulin when incubated with intact cells and caused single-stranded breakage of DNA. Fluphenazine-mustard possesses potent antiproliferative and cytotoxic properties against malignant cell lines that are likely to be mediated through both of these actions.  相似文献   
882.
Exercise and work potential of a patient with coexistent myophosphorylase and myoadenylate deaminase (AMPDA) deficiency was compared with that of three patients with myophosphorylase deficiency alone. The patient with the combined defect failed to produce an abnormal rise in serum ammonia or hypoxanthine as seen in the other patients after forearm exercise. Maximum oxygen consumption and work rates during cycle ergometer testing were similar in all patients, but well below controls. The occurrence of two defects involving short-term energy metabolism in muscle presents an opportunity to define further the metabolic role of AMPDA.  相似文献   
883.
The paper describes the examinations of 353 patients with various cardiovascular pathologies and changes in the end-portion of the ECG ventricular complex. For that purpose potassium chloride, obsidan, orthostatic and hyperventilation tests were used. The examinations demonstrated that the ECG changes were of functional nature in 178 patients, of organic nature in 155 patients and of mixed nature in 20 patients which was important for reliable diagnostic and expertise conclusions.  相似文献   
884.
Summary Resistant club foot remains an unsolved problem because of the complex aetiological and pathological factors, and is still seen quite frequently, especially in developing countries. The posteromedial skin contracture is a potent deforming force which is responsible for many failures or relapses. I report the results of an operation in which a rotation skin flap was combined with an extensive soft-tissue release. The age of the children was from 9 months to 10 years. The follow-up period was from one to 9 years with an average of 43 months, and in 50 cases for more than 5 years. I consider that the outcome has been excellent or good in 94 out of 100 feet.
Résumé Le pied bot invétéré demeure un problème mal résolu en raison de la complexité des facteurs étiologiques et anatomiques et il est encore bien souvent rencontré, notamment dans les pays en voie de développement. La rétraction cutanée postéro-interne représente un puissant élément de la déformation, qui est responsable de bon nombre d'échecs ou de récidives. Nous rapportons les résultats d'une opération qui associe un lambeau cutané de rotation à la libération des parties molles. L'âge des enfants était compris entre neuf mois et dix ans. Le recul est de un à neuf ans, avec une moyenne de 43 mois. Cinquante enfants ont été suivis plus de cinq ans. Les résultats sont excellents ou bons dans 94% des cas.
  相似文献   
885.
Hyponatremia is a common complication of chronic advanced CHF unresponsive to the usual therapeutic measures. Thus low levels of serum sodium are a significant marker for severe CHF refractory to the more conventional measures. The combined use of ACE inhibitors and diuretics is generally very effective in correcting the hyponatremic state and often helpful in reversing CHF.  相似文献   
886.
Long-term dialysis patients frequently develop acquired renal cystic disease (ARCD). The discovery of ARCD and renal cell carcinoma in one of our hemodialysis patients led us to review the literature. ARCD has been described mainly in the maintenance hemodialysis (MH) population. Therefore, we investigated 20 peritoneal dialysis (PD) patients for ARCD using ultrasonography. Seven patients (35%) had detectable cysts and two patients (10%) had multiple bilateral cysts. One patient had a large asymptomatic complex cyst that proved to be an adenocarcinoma. Our study suggests that ARCD is relatively common in the PD population, and we speculate that it may be related more to length of time in end-stage renal disease (ESRD) than to the mode of dialysis. The potential for malignant change appears to justify a routine screening examination with ultrasonography and/or computerized tomography (CT) to detect this recently described and probably underrecognized entity.  相似文献   
887.
Renal magnesium wasting in two families with autosomal dominant inheritance   总被引:3,自引:0,他引:3  
Hypomagnesemia due to isolated renal magnesium loss was demonstrated in two unrelated families with autosomal dominant mode of inheritance. Magnesium infusions performed in two patients showed not only a reduced renal magnesium threshold but also a lowered renal tubular maximum for magnesium. All members of both families who presented with hypomagnesemia had also a lowered excretion of calcium in the urine, presumably as a consequence of increased reabsorption in Henle's loop.  相似文献   
888.
889.
890.
The use of adjuvant radiation therapy in breast cancer patients treated with mastectomy and adjuvant chemotherapy has been controversial. In order to assess the necessity and effectiveness of adjuvant radiation therapy in this setting, we reviewed the results in 510 patients with T1-T3 tumors and pathologically positive nodes or tumors larger than 5 cm and negative nodes who were treated with adjuvant chemotherapy. Patients with four or more positive nodes or at least one positive apical node were randomized to receive either five or ten cycles of cyclophosphamide/Adriamycin (Adria Laboratories, Columbus, OH) (CA) and patients with one to three positive nodes or operable tumors larger than 5 cm and pathologically negative nodes were randomized to receive eight cycles of either cyclophosphamide, methotrexate, and 5-fluorouracil (5-FU) (CMF) or methotrexate and 5-FU (MF) chemotherapy. Two hundred six of these patients were subsequently rerandomized to receive either no further treatment or adjuvant radiotherapy. Thirty-five patients withdrew after randomization, including 34 who declined to receive radiotherapy. Radiation therapy consisted of 4,500 cGy in 5 weeks to the chest wall and appropriate draining lymph nodes. Median follow-up from chemotherapy randomization is 45 months for patients in the CA arm and 53 months for those in the CMF/MF arm. The crude rate of local failure (chest wall or draining lymph node areas) as first site of failure for patients randomized to receive chemotherapy only was 14%; for those randomized to receive both chemotherapy and radiotherapy it was 5% (P = .03). For patients in the CMF/MF arm, the rate of local failure as the first site of failure was nearly the same for patients randomized to chemotherapy only as for those randomized to adjuvant radiotherapy as well (5% v 2%). For patients in the CA arm, the crude rate of local failure was 20% for patients randomized to receive chemotherapy only, and 6% for those randomized to both types of adjuvant treatment (P = .03). Among the 43 patients treated with CA who actually received radiotherapy, there was only one local failure, compared with 12 local failures among the 59 patients (20%) who actually did not receive radiotherapy (P = .007). No significant difference was seen in disease-free survival or overall survival in either the CA or the CMF/MF arm between patients randomized to receive radiation therapy and those randomized to no further treatment.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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