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81.
Patients with suspected illness due to mercury in dental amalgam were classified as tolerant or intolerant depending on their psychosomatic responses following in vivo epicutaneous provocation with low doses (patch test doses) of metallic mercury and phenylmercuric acetate. Ten intolerant patients and nine tolerant patients plus seven healthy amalgam-free and metal non-allergic controls were recruited to the study. Peripheral blood lymphocytes were exposed in vitro to three concentration of mercuric chloride (0.92, 1.83 and 3.68 microM) with and without 10 microg phytohaemagglutinine (PHA)/ml and the release of serotonin into the supernatant was measured. Lymphocytes exposed only to HgCl(2) showed no significant dose-dependent increase of serotonin, but the response of the tolerant patients was significantly higher compared with the controls. No other differences were found. Co-culture with mercuric chloride and PHA showed a statistically significant dose-dependant release of serotonin, but no differences between the three clinical groups could be detected. Thus, our results could not validate the concept of mercury tolerance and intolerance.  相似文献   
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Although favorable effects of débridement with chondrectomy and drilling or abrasion have been reported in treating of cartilage lesions in the knee joint; however, in most cases an additional intervention is generally performed during arthroscopy. We studied 53 consecutive patients with solitary chondral lesions in the weight-bearing part of the knee and treated 86 cartilage lesions by arthroscopic débridement, including a detailed removal of damaged or undermined cartilage. We evaluated the postoperative course by questionnaire (mean follow-up 6.5 years, response rate 83%). All patients reported a positive effect of chondrectomy: 69% considered the knee considerably better or cured and 77% regarded the effect as permanent. There was no complication of the arthroscopies performed, and no patient noted any deterioration in the condition. We therefore recommend routine chondrectomy of cartilage lesions when these are found during an arthroscopy.  相似文献   
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d-生物素的立体专一性全合成研究   总被引:1,自引:0,他引:1  
对confaione的d-生物素(1)全合成进行了改进,从半胱氨酸计算,总收率3.7%。5与4-溴代三苯膦丁酸甲酯进行Wittig-Schlosser缩合反应可立体专一性地转化成反式-烯(6)。以叠氮三甲基硅烷代替叠氮化锂亲核进攻9分子中C3-溴原子,可显著地提高顺式-叠氮内酰胺10的收率。  相似文献   
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刘荔荔  程民  高申 《药学学报》1994,29(7):539-543
用柱切换HPLC法建立了豚鼠血浆和皮下组织液中诺氟沙星银体内主要解离物诺氟沙星的测定方法。预处理柱为μ-BondapakC18,37~50μm,50mm×5mmID;分析柱为YWG-C18,10μm,150mm×5mmID。预处理流动相为0.008mo1/L磷酸缓冲液,流速为3ml/min;分析流动相为甲醇—0.008mol/L磷酸缓冲液—0.05mol/L四丁基溴化铵(25:75:4)。紫外检测波长为280nm。皮下组织液及血浆中的线性范围分别为100~3200ng/ml(r=0.9999)和2~128μg/ml(r=0.9999);最低检测浓度分别为10ng/ml和0.25μg/ml,方法的平均回收率为102%,日内及日间偏差均小于7%。  相似文献   
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The binding of [3H]desipramine to human brain tissue was characterized. Competition studies in the frontal cortex and hypothalamus revealed a single-site binding model for noradrenaline (Ki 120-190 microM). The noradrenaline uptake inhibitors nisoxetine, nortriptyline and desipramine fitted two-site binding models and these compounds exhibited 10-80 times lower Ki values than the serotonin uptake inhibitor citalopram. The high-affinity component of the nisoxetine-sensitive [3H]desipramine binding (Ki 50-110 nM) approximated the binding sensitive to noradrenaline. This binding fraction was defined as that sensitive to 1 microM nisoxetine and showed a maximum binding capacity (Bmax) of 380 +/- 80 fmol/mg protein and an apparent Kd of 5.1 (4.5-5.7) nM in the hypothalamus. The binding was also investigated in 25 additional brain regions without finding detectable amounts of binding. However, when the specific binding was defined as that sensitive to 100 microM nisoxetine, low-affinity binding where Bmax and Kd were not possible to determine was obtained in all brain regions investigated. It is concluded that [3H]desipramine binding to human brain tissue represents multiple binding sites. Only when regarding binding sensitive to noradrenaline and to the high-affinity component of noradrenaline uptake inhibitors is the binding saturable and of high affinity. It is possible that this site represents the uptake site for noradrenaline.  相似文献   
87.
Abstract – For the objective measurement of oral mucosal dryness or moisture, a device registering oral mucosal surface slide friction has been developed. Two prototypes, Probe I and Probe II, have been tested. Probe I was constructed for initial testing of the method and was based on easily accessible electrical components. Probe I was computerized and developed for more accurate registration and also for easy handling. Reliability and validity tests were carried out on Probe I as well as on Probe II. In repeated in vitro measurements, the probes showed good reproducibility. Validity was assessed on healthy subjects injected with methylscopolamine nitrate submucosally in the labial sulcus. All subjects experienced a pronounced oral mucosal dryness within half an hour. Registration with the surface slide friction device showed maximum friction values 1-2 h after injection. These reliability and validity tests gave good results for both Probe I and Probe II, but Probe II had several practical advantages over Probe I. Both probes were considerably more sensitive to changes of the oral mucosal surface than the previously used simple friction test using the back of a mouth mirror.  相似文献   
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