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1.
Segregation analysis of leprosy in families of northern Thailand   总被引:4,自引:0,他引:4  
Sixty-three families with multiple instances of leprosy were identified through a major leprosy treatment center in northern Thailand. Complex segregation analyses for single major genes or polygenic inheritance were performed using the maximum-likelihood routine POINTER to determine the most likely etiologic model of genetic susceptibility. Liability differences between men and women were considered in these models. When individuals were considered to be affected because they had any form of leprosy, a generalized major gene model with nearly dominant parameters on the liability scale, but additive penetrances, was found to be the most likely. When only those individuals who had tuberculoid forms of leprosy were considered to be affected, a recessive model was found to be the most likely; however, the discrimination between various models was poor. Further analyses are necessary to delineate genetic mechanisms to explain these apparently divergent results. In particular, methods of testing two locus models should be considered.  相似文献   
2.
Inhibition of protein synthesis can alter cellular responsiveness to the classical anticancer drugs. The in vitro response of Chinese hamster ovary (CHO) cells to cisplatin with or without sparsomycin (Sm) was studied with the use of [3H]leucine and [methyl-3H]thymidine incorporation and clonogenic assay. Pretreatment of exponentially growing CHO cells with 1 microgram Sm/ml for 3 or 5 hours decreased [3H]leucine incorporation by 20% and resulted in significant resistance to cisplatin (P = .005). Sm in a concentration of 10 micrograms/ml reduced [3H]leucine and [methyl-3H]thymidine incorporation after 3 hours by 92 and 84%, respectively, and resulted in potentiation of the cisplatin cytotoxicity (P = .004). This effect was the same in the case of nonproliferating cells (P = .005), while protection due to Sm (1 microgram/ml) was seen only during cell proliferation. Simultaneous incubation and postincubation with Sm proved to have much less or no potentiating effect on cisplatin. The mechanisms of both protection and potentiation are still not clear, but our data indicate that Sm is a promising drug for further studies on the modulation of the cancer cell response to classical anticancer drugs.  相似文献   
3.
A total of 91 eligible patients with metastatic cancer have been treated in a series of phase II trials of the novel pentacyclic pyrroloquinone, fosquidone. Tumour types were breast (24), ovary (25), head and neck (21) and melanoma (21). All patients, except those with melanoma had received prior chemotherapy. The drug was given intravenously as a 20 min infusion, at the dose of 120 mg/m2 on days 1 to 5 of a 3 week cycle. Treatment was well tolerated; the only significant side-effects being mild headaches and generalised musculo-skeletal pains. Response was assessed after 2 cycles of therapy. Only one patient (with head and neck cancer) achieved an objective partial response, lasting 6 weeks. A total of 12 patients demonstrated stable disease for a median duration of 15 to 20 weeks. Using this schedule of administration, fosquidone has no significant antitumour activity in this group of tumours.  相似文献   
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BACKGROUND: The mainstay of treatment for pemphigus is systemic corticosteroids. Different adjuvants have been used to reduce side-effects of long-term corticotherapy. Gold is an anti-inflammatory drug used in autoimmune diseases, whose use has waned with the advent of new immunosuppressive agents. OBJECTIVE: To study the outcome of the use of intramuscular gold treatment of pemphigus vulgaris refractory to previous therapies. METHODS: Thirteen patients with pemphigus vulgaris who had failed to respond to several prior therapies were treated with aurothiomalate, as a steroid-sparing agent. Patients were monitored to assess disease activity and gold toxicity. RESULTS: Seven patients achieved complete remission. Four patients were able to taper prednisone doses, although pemphigus flared when prednisone was discontinued or reduced. Toxicity was observed in the other two patients. CONCLUSIONS: In 53.4% of the patients, the use of chrysotherapy resulted in the complete clearing of the disease, discontinuation of all systemic therapies and induced a long-term clinical remission. Prednisone doses were able to be reduced in the remaining 46.6%. Any side-effects were reversible with drug discontinuation. Gold therapy showed efficacy as a secondary line treatment in refractory pemphigus vulgaris.  相似文献   
6.
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea.  相似文献   
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Fourteen derivatives of sparsomycin (1) were synthesized. Six of them were prepared following a novel synthetic route starting from the L-amino acid alanine. Some physicochemical properties, viz. lipophilicity and water solubility, of selected derivatives were measured. The biological activity was tested in vitro in cell-free protein synthesis inhibition assays, in bacterial and tumor cell growth inhibition assays, and in the L1210 leukemia in vivo model in mice. Also for selected drugs the acute toxicity in mice was determined. Ribosomes from both an eukaryotic and a prokaryotic organism were used in the protein synthesis inhibition systems. A linear correlation between the lipophilicity parameters measured was observed. Water solubility and drug toxicity in mice were found to be linearly correlated with lipophilicity. All the derivatives studied are more lipophilic than 1. The deshydroxysparsomycin analogues (30-33) showed an interesting phenomenon: increase in hydrophobicity was accompanied by a considerable increase in water solubility. We found that an increase in hydrophobicity of the drug as a result of replacing the SMe group of 1 with larger alkylthio groups causes an increase in the biological activity of the drug. However, not only the hydrophobicity but also shape and size of the substituent are important; in the homologous series 1-9-10-11-12, 21-22-23-24, and 30-31-32-33, highest protein synthesis inhibitory and in vitro cytostatic activity is found with compounds 11, 23, and 32, respectively, and in comparison with the highly active n-butyl compound 10, the isomeric tert-butyl compound 13 is rather inactive. Polar substituents replacing the SMe group, i.e. Cl in 17 and 35, also render the molecule inactive. Substituting the bivalent sulfur atom for a methylene group decreases the drug's activity. This effect can be compensated for by increasing the length of the alkylsulfinyl side chain. The agreement between the results derived from cell-free and "in vivo" tests is good. The assays using ribosomes of bacterial and eukaryotic organisms give similar results although the latter seem to be more sensitive to changes in hydrophobicity of the drug. Our results confirm the presence of a hydrophobic region at the peptidyl transferase center of the ribosome; the interaction of sparsomycin with this region is more pronounced in the eukaryotic particles. The sparsomycin analogues 11, 23, and 30 show the highest antitumor activity against L1210 leukemia in mice, their median T/C values are 386, 330, and 216%, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
9.
Cervical smears were reviewed from patients in whom a cytological abnormality was followed, after an interval without interference, either by regression to `negative' or else by progression to invasive carcinoma. Twenty-eight cases were from a previously analysed series with positive smears and an interval of at least two years before investigation, resulting from refusal or failure to trace. Slides were also reviewed from 25 cases in which `positive' smears had regressed to negative without escaping from surveillance, and from 10 patients subsequently developing invasive carcinoma whose previous slides, taken several years earlier, showed abnormalities on review. None of these 63 patients had any biopsy or other surgical procedure to the cervix between the initial smear and the outcome.

Slides showing `superficial cell dyskaryosis' and/or well-differentiated `parabasal cell dyskaryosis' were found only among the groups with subsequent regression. Those showing dissociated poorly differentiated dyskaryotic parabasal cells regressed to negative in two cases and progressed to invasion in nine. This suggests that many examples of spontaneous regression correspond to mild dysplasias which are not precancerous, and overdiagnosis must often have resulted in unnecessary surgical procedures in the past.

`Regressing' and `progressing' groups both included cases in which the spatula had removed coherent pieces of undifferentiated epithelium. These are difficult to interpret cytologically. In nine of them (including four which regressed) the cytological picture was that of carcinoma in situ. The remainder (14 cases) were probably examples of reserve cell hyperplasia, and it is noteworthy that, of the 21 cases subsequently progressing to invasive carcinoma, five were preceded by appearances of this type. It is concluded that cell aggregates suggesting an unusual degree of reserve cell hyperplasia are a danger signal and require careful surveillance.

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