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51.
ND Henderson SM Lacy CC O'Hare JA Hartley S McClean LP Wakelin LR Kelland DJ Robins 《Canadian Metallurgical Quarterly》1998,13(7):749-768
The aim of this work was to develop new bifunctional alkylating agents which damage DNA in a selective manner. In order to extend our previously published work on conformationally restricted nitrogen mustards containing one piperidine ring, new bispiperidine derivatives were designed with varying lengths of carbon chain between the two rings and structure-activity relationships in these systems were studied. Thus samples of new bispiperidine salts 22-26 with chloromethyl groups at the 2-positions and a bridge between the two nitrogen atoms of 2-6 carbon atoms were synthesized. The analogous new bis(p-nitrophenylcarbamates) 17-21 were also prepared. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation with different distances between the two alkylating sites. The bispiperidines 22-24 were shown to alkylate guanines at the 7-position in the major groove of DNA more selectively than melphalan. The bispiperidine 22 with the shortest two carbon bridge was the most reactive but it was less cytotoxic than melphalan in a human colon carcinoma cell line (IC50 value approximately 30 microM) and in a human chronic myeloid leukaemia cell line (IC50 value approximately 12 microM). The most cytotoxic compound in the latter cell line was the carbamate 17, with an IC50 value of approximately 0.3 microM, and carbamates 17, 19 and 20 were most potent in a panel of human ovarian carcinoma cell lines. These compounds also showed circumvention of acquired cisplatin resistance in three paired cell lines. The carbamates 17-21, however, were less efficient at alkylating and cross-linking naked DNA than the bispiperidines 22-26. 相似文献
52.
OBJECTIVE: To investigate the role of tumor persistence in patients submitted to irradiation therapy and radical hysterectomy. DESIGN: A retrospective analysis of prognostic factors. LOCATION: Hospital A.C. Camargo, S?o Paulo, Brazil, a private non-profitmaking foundation and tertiary referral centre. PATIENTS: A total of 629 cases of invasive squamous cell carcinoma of the cervix were studied. Criteria for inclusion in the study were: confirmed histological diagnosis of squamous cell carcinoma and no previous treatment (except for preoperative radiotherapy carried out at the Hospital A.C. Camargo itself). At the end of the follow-up period, 410 patients (65%) had no evidence of disease and 219 (34.8%) had died because of the tumor. INTERVENTION: The patients were submitted to radical surgery and radiation therapy, separately or in combination between 1953 and 1982. MAIN OUTCOMES MEASURES: Multivariate analysis of the different variables was performed according to the Cox regression method. RESULTS: The variables of prognostic value were, in decreasing order of importance: the decade of patient admission (p = 0.0001), the modality of therapy employed (p = 0.0005), the presence of residual tumor in the surgical specimens (p = 0.0055) and the clinical stage of the disease (p = 0.0575). CONCLUSION: Radiation therapy controlled a considerable number of local tumors and pelvic lymph nodes but not all of them in every patient. There is a specific group of patients for whom radical surgery is necessary to achieve control of the disease. 相似文献
53.
H Albrecht M Schwecht W P?llmann D Parag LP Erasmus N K?nig 《Canadian Metallurgical Quarterly》1998,69(12):1066-1073
Upper limb ataxia is one of the most disabling symptoms of patients with multiple sclerosis (MS). There are some clinically tested therapeutic strategies, especially with regard to cerebellar tremor. But most of the methods used for treatment of limb ataxia in physiotherapy and occupational therapy are not systematically evaluated, e.g. the effect of local ice applications, as reported by MS patients and therapists, respectively. We investigated 21 MS patients before and in several steps 1 up to 45 min after cooling the most affected forearm. We used a series of 6 tests, including parts of neurological status and activities of daily living as well. At each step skin temperature and nerve conduction velocity were recorded. All tests were documented by video for later offline analysis. Standardized evaluation was done by the investigators and separately by an independent second team, both of them using numeric scales for quality of performance. After local cooling all patients showed a positive effect, especially a reduction of intentional tremor. In most cases this effect lasted 45 min, in some patients even longer. We presume that a decrease in the proprioceptive afferent inflow-induced by cooling-may be the probable cause of this reduction of cerebellar tremor. Patients can use ice applications as a method of treating themselves when a short-time reduction of intention tremor is required, e.g. for typing, signing or self-catheterization. 相似文献
54.
S Lamy LP da Silva B Lopes P Pacheco J Lavinha JM Amaral JM Marques 《Canadian Metallurgical Quarterly》1997,10(2-3):209-212
A case of cystic fibrosis presented in the neonatal period with respiratory symptomatology associated with early pancreatic insufficiency is reported. The CFTR gene molecular analysis was found to be a compound heterozygotes for delta F508 and G542X. The rarity of this mode of presentation and the inclusion of this entity in the differential diagnosis for neonatal respiratory distress syndrome is emphasised. The pathogenesis and some therapeutic aspects carried out in our patient, which might have improved the life expectancy of patients with this disease, are discussed. 相似文献
55.
SJ Mubarak AR Hargens CA Owen LP Garetto WH Akeson 《Canadian Metallurgical Quarterly》1976,58(7):1016-1020
The wick catheter technique was developed in 1968 for measurement of subcutaneous pressure and has been modified for easy intramuscular insertion and continuous recording of interstitial fluid pressure in animals and humans. Studies in dogs of the anterolateral compartment of the leg in simulation of the compartment syndrome showed the technique to be accurate and reproducible. The wick catheter technique is capable of important clinical applications in the diagnosis and treatment of acute and chronic compartment syndromes. 相似文献
56.
57.
Analysis of amino acids is complicated by treatment with ampicillin. High voltage electrophoresis, which is convenient for the qualitative assessment of metabolic diseases, yields smears of ampicillin that mask the bands of citrulline, homocitrulline, phenylalanine, cystine, and homocystine. The addition of penicillinase prior to high voltage electrophoresis eliminates ampicillin and other penicillins and reveals these key amino acids. 相似文献
58.
An anonymous questionnaire inquiry performed among 324 school teachers in the Randers area with the purpose of elucidating teachers' knowledge about asthma is presented. To a series of statements about asthma, the teachers should answer yes, no or don't know. A limited knowledge about asthma in children was found. The knowledge about medicamental treatment was particularly limited. Only 57 per cent knew that wheezing after physical exertion is a strong indicator of asthma. Only five per cent had received proper instruction. This latter group had a significantly better knowledge of medical treatment (p < 0.0001-0.05). It is recommended that instruction in children's diseases, especially asthma should be reintroduced in teachers' training colleges. 相似文献
59.
Effects of total coumarins, essential oil and water extracts of Cnidium monnieri on plasma prostaglandin (PGE2 and PGF2 alpha) and cyclic nucleotide levels in rats of Kidney-Yang insufficiency were studied. 55 rats were divided randomly into 5 groups, Group I was administered orally with saline (normal group), group II was injected with intraperitonally hydrocortison acetate to induce Kidney-Yang insufficiency (control group), group III, group IV and group V (experimental groups) were injected with hydrocortison acetate, the same as group II, and administered orally with the total coumarins, essential oil and water extracts of Fructus Cnidii respectively. The levels of plasma PGE2, PG2 alpha and plasma cAMP, cGMP were measured. In group II, in comparing with those of group I, the levels of plasma PGE2, and PGF2 alpha decreased significantly (P < 0.01), and the value of cAMP/cGMP also lowered obviously (P < 0.01) due to the significant reduction of cAMP and insignificant change of cGMP. In group III and group V, the above-mentioned indices changed significantly (P < 0.01 or 0.05) compared with those of group II, and after treatment it normalized basically in comparing with those of group I. In group IV, those indices didn't change regularly and apparently as group III and group V did, compared with group II, and could not normalize satisfactorily. It is suggested that the coumarins in the fruit of Cnidium monnieri are probably the effective ingredients to invigorate Kidney and strengthen Yang, while the efficacy of essential oil remained unconfirmed. 相似文献
60.