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31.
BACKGROUND: It is important to choose a valid spatial scale to study health differences in a geographical perspective. Many scales can be valid and a combination is required to understand the spatial distribution of a given health problem. Geographic distribution of lung cancer was studied in France using different scales to illustrate the importance of changing scales in health geography. METHODS: Standardized rates (direct method) for lung cancer were calculated for the period 1988-92 and mapped at different scales. RESULTS: Original spatial structure was observed for each scale. This proved that different interactions occur at each scale between environmental and social factors. Changing the scale allowed a better understanding of variations in the spatial distribution of lung cancer. CONCLUSIONS: The validity of a regional scale to study health geographical distributions is questioned. Changing the scale would allow proposing action to improve health promotion. 相似文献
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Samples of extracellular fluid from striatum and nucleus accumbens of anaesthetised rats undergoing opiate withdrawal were collected using microdialysis and then analysed for adenosine and its metabolites using high performance liquid chromatography (HPLC) and ultraviolet (UV) detection. Although the amount of adenosine present in the dialysate from either brain region was below the limit of detection by 90 min after probe placement, the metabolites could still be detected. Samples of dialysates collected from the nucleus accumbens contained significantly higher concentrations of hypoxanthine and inosine following naloxone challenge. The data are compatible with the hypothesis that endogenous adenosine might be involved in the expression of the opiate abstinence syndrome. 相似文献
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Predictive factors of acute urinary morbidity after iodine-125 brachytherapy for localised prostate cancer: a phase 2 study. 总被引:4,自引:0,他引:4
Naji Salem Michelle Simonian-Sauve Roland Rosello Claude Alzieu Gwenaelle Gravis Dominique Maraninchi Franck Bladou 《Radiotherapy and oncology》2003,66(2):159-165
PURPOSE: To analyse predictive factors of acute urinary morbidity after transperineal permanent prostate brachytherapy. METHODS AND MATERIALS: Sixty patients treated in a phase 2 study with iodine-125 brachytherapy (9/1998 to 2/2000) for localised prostate adenocarcinoma were analysed after at least 1-year follow-up. Prescribed dose was 144 Gy and all patients had a pre-planning and a post-implant dosimetry. Urinary morbidity was evaluated prospectively using the Radiation Therapy Oncology Group (RTOG) scale. We examined the relationship between pre-implant ultrasound prostate volume, post-implant CT-scan prostate volume, neoadjuvant hormonotherapy, total number of needles and seeds, post-implant dosimetry variables, first 30 vs. last 30 treated patients and post-implant urinary morbidity. RESULTS: All patients experienced some degree of urinary distress symptoms after treatment. Symptoms were generally mild grade 1 in 56% and grade 2 in 10% lasting less than 6 months. Eight patients (13%) required bladder catheter for acute urinary obstruction. At 1-year follow-up, nine patients (15%) complained from persistent dysuria requiring in three cases endoscopic prostate resection. The percentage of urethra volume receiving 216 Gy (cut-off 40%) and the pre-implant prostate volume (cut-off 31 ml) were the only statistically significant predictor of grade 2-3 or persistent urinary morbidity on multivariate analysis. CONCLUSION: Our short-term data suggest that both pre-implant prostate volume value and post-implant V.U. 150 value might be predictors for urinary morbidity after prostate brachytherapy. 相似文献
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R. J. Cote E. C. Skinner C. E. Salem S. J. Mertes F. Z. Stanczyk B. E. Henderson M. C. Pike R. K. Ross 《British journal of cancer》1998,78(3):413-418
Prostate cancer is a disease associated with androgens. It has been hypothesized that reducing the conversion of testosterone (T) to dihydrotestosterone (DHT) in the prostate by the use of the drug finasteride, a 5alpha-reductase inhibitor, will reduce the incidence of prostate cancer. We investigated the chemopreventive potential of finasteride by evaluating its effect on the prostate gland of men with elevated serum prostate-specific antigen (PSA). Fifty-two men with elevated PSA and prostate sextant biopsies negative for cancer were randomized to receive finasteride 5 mg day(-1) (27 patients) or no medication (25 patients) for 12 months and were rebiopsied at 12 months. The biopsies were evaluated for the presence of cancer, the proportion of glandular and hyperplastic tissue, and the presence of high-grade prostatic intraepithelial neoplasia (PIN). Epithelial proliferation was assessed in the prestudy and 12-month biopsies by immunohistochemistry using antibody to proliferating cell nuclear antigen (PCNA). Serum blood samples were drawn at baseline and after 1, 3, 6 and 12 months of study. In the control group, serum levels of PSA and T were unchanged throughout the 12 months. In the finasteride group, PSA decreased 48% (P < 0.001), DHT decreased 67% (P < 0.001) and T increased 21% (P < 0.001). Histological evaluation of prestudy and 12-month biopsy specimens revealed that the finasteride group had a 30% reduction in the percentage of hyperplastic epithelial tissue (P = 0.002), although this decrease was not statistically significantly different between the finasteride and control groups (P = 0.11). In patients with PIN on prestudy biopsy, no change occurred in the PIN lesions with finasteride treatment. Finasteride also had no effect on the proliferation index of prostatic epithelial cells. Of the 27 patients treated with finasteride, eight (30%) had adenocarcinoma of the prostate detected on the 12-month biopsy, compared with one (4%) of the control patients (P = 0.025). In the treatment group, six cancers occurred in the eight patients with PIN on the prestudy biopsy; in the observation group no cancers were detected in the five patients with PIN on the prestudy biopsy (P = 0.021). Two cancers occurred in the 19 men in the treatment group with no evidence of PIN on the prestudy biopsy, compared with one cancer in the 20 men in the observation group with no evidence of PIN on the prestudy biopsy (P = 0.60). This study, using a novel model for evaluating short-term efficacy of chemopreventive or therapeutic agents in men at high risk of prostate cancer, provides little evidence that finasteride is an effective chemopreventive agent for prostate cancer in men with elevated PSA. 相似文献
37.
应用改进的眼震图检查先天性眼球震颤 总被引:2,自引:0,他引:2
目的评价改进后的眼震图对先天性眼球震颤波形的分析,为其手术治疗提供较为精确的量化标准.方法改进电生理仪的视网膜电图(EOG)程序,分别记录68例患者33cm原在位、右5°、10°、15°、20°,左5°、10°、15°、20°,3m原在位及闭眼的波形,并对其中28例手术患者术前和术后的眼震图进行比较.结果68例患者中,跳动型48例,其中水平跳动46例,垂直跳动2例;水平钟摆型20例.跳动型中,有代偿头位的40例,钟摆型无明显代偿头位.28例手术患者中,水平跳动型26例,水平钟摆型2例.26例跳动型患者均有中间位和代偿头位.术后20例代偿头位消失,6例代偿头位在左5°~10°.按震频、振幅、震强的分组中,处于中等震频、振幅、震强范围内的多见.结论改进的眼震图可以对眼震的振幅、震频、震强、中间位进行量化的检测,从而指导其治疗. 相似文献
38.
Zhang JD Cao YB Xu Z Sun HH An MM Yan L Chen HS Gao PH Wang Y Jia XM Jiang YY 《第二军医大学学报》2006,27(6):664-664
Antifungal activity of natural products is being studied widely. Saponins are known to be antifungal and antibacterial. We have isolated eight steroid saponins from Tribulus terrestris L. , namely TTS-8, TTS-9, TTS-10, TTS-11, TTS-12, TTS-13, TTS-14 and TTS-15. TTS-12 and TTS-15 were identified as tigogenin-3-O-β-D-xylopyranosyl(1→ 2)-[-β-D-xylopyranosyl( 1 → 3 ) 3-β- D-glucopyranosyl ( 1 → 4 )- 1- α-L-rhamnopyranosyl ( 1 → 2 ) 3-β-D-galactopyranoside and tigogenin-3-O-β-D-glucopyranpyranosyl(1→2)-[-β-D-xylopyranosyl(1→ 3)3-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside, respectively. The in vitro antifungal activities of the eight saponins against six fluconazole-resistant yeasts, Candida albicans, Candida glabrata, Candida para psilosis , Candida tropicalis , Candida krusei , and Cryptococcus neo f ormans were studied using microbroth dilution assay. The results showed that TTS-12 and TTS-15 were very effective against several pathogenic candidal species and C. neoformans in vitro. It is noteworthy that TTS-12 and TTS-15 were very active against fluconazole-resistant C. albicans (MIC80 = 4.4, 9.4 mg/ml), C. neoformans (MIC80 =10.7, 18.7 mg/ml) and inherently resistant C. krusei (MIC80 =8.8, 18.4 mg/ml). So in vivo activity of TTS-12 in a vaginal infection model with fluconazole-resistant C. albicans was studied in particular. Our studies revealed TTS-12 also showed in vivo activities against fluconazole-resistant yeasts. In conclusion, steroid saponins TTS-12 and TTS-15 from Tribulus terrestris L. have significant in vitro antifungal activity against fluconazole-resistant fungi, especially TTS-12 also showed in vivo activity against fluconazole-resistant C. albicans. 相似文献
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