Clinical and radiographic diagnosis of occlusal caries. a study in vitro

summary Various methods of diagnosing occlusal caries have been described, but only visual, clinical examination and radiographic examination are commonly used in dental practice. This laboratory study investigated the ability of 12 examiners to detect the presence or absence of occlusal caries in 48 extracted molar teeth using these two techniques. The presence or absence of caries was subsequently verified by sectioning the teeth. Diagnosis from visual examination was poor, only 48.7% of lesions in dentine being detected. Radiographic diagnosis was better with 62.2% of dentine lesions being found. However, this increase in sensitivity of the diagnosis was accompanied by a decrease in specificity with the number of false positive diagnoses increasing when the radiograph was used. Therefore, although the bite-wing radiograph may be regarded as a safety net for the diagnosis of occlusal caries, it must be interpreted with caution bearing in mind the possibility of false positive diagnoses.     

小藤铃儿草的生物碱成分

自小藤铃儿草Dactylicapnos torulosa(Hook.f ct Thomas.)Hutchins中分得六个单体,通过UV,IR,MS,~1HNMR和~(13)CNMR解析,鉴定了四个,其中一个为新化合物,命名为紫金龙碱(zijinlongine,Ⅰ),其他三个为已知化合物:氯化1-甲氧基小檗碱(1-methoxylberberium chloride,Ⅱ),氯化三乙基苯胺(triethylphcnylamium chloride,Ⅲ)和异紫堇定(isocorydine,Ⅳ)。Ⅱ和Ⅲ系首次从植物中得到。     

米非司酮抗人子宫内膜癌裸鼠移植瘤作用的实验研究

目的：观察米非司酮抗人子官内膜癌裸鼠移植瘤的作用，为临床应用提供依据。方法：将裸鼠分为米非司酮、三苯氧胺、米非司酮＋三苯氧胺、对照４组，用药并观察移植瘤生长情况，电镜观察移植瘤，测定裸鼠血清雌二醇。结果：米非司酮抗癌作用与三苯氧胺相似，二者联合作用增强。米非司酮使癌细胞坏死，内质网及线粒体肿胀，使裸鼠血清雌二醇升高。结论：米非司酮有抗子宫内膜癌作用，与三苯氧胺联合作用增强。     

Interleukin-4 induces a substance in bone marrow stromal cells that reversibly inhibits factor-dependent and factor-independent cell proliferation

Bone marrow-derived stromal cell monolayers pretreated with recombinant interleukin-4 (IL-4) inhibit the growth of hematopoietic cells. This was demonstrated by inhibition of fresh bone marrow-derived, IL-3- induced soft agar colonies as well as by inhibition of proliferation of IL-3-dependent cell lines and of a Friend virus-transformed erythroleukemic cell line. Pretreatment of stromal cells with IL-4 for five to seven days induced the inhibitory activity. IL-4 could then be removed before "plating" the bone marrow cells in soft agar, indicating that the inhibitory activity did not depend on the action of IL-4 on the precursors of the soft agar colonies. The inhibitory activity appears to be mediated by a soluble factor since inhibition was achieved even if the stromal cell layer was separated from the colony forming cells by an "empty" agar layer. However, supernatants of IL-4- induced stromal cell layers had no detectable inhibitory activity. The inhibitory action of the IL-4-pretreated stromal cell lines was not the result of killing of the precursor cells since it could be reversed if the agar layer containing the colony-forming cells was removed from the stromal cell layer and cultured with IL-3. Hydrocortisone (HC) blocked the inhibitory effect if added either in the IL-4 preincubation phase or during the colony formation stage, implying that HC blocked both induction of the inhibitory activity and its release or its effector function. A homogenous long-term stromal cell line could not be induced to exert the inhibitory activity; partial inhibition could be achieved with pure macrophages stimulated with IL-4 and CSF-1, suggesting that the inhibitory activity induced by IL-4 in mixed stromal cell layers may depend on a complex mechanism involving more than one cell type. Northern analysis of RNA from IL-4-induced and uninduced stromal cells indicated that IL-4 did not upregulate expression of CSF-1 or transforming growth factor-beta (TGF-beta) and only modestly increased expression of tumor necrosis factor, suggesting that these cytokines were not responsible for the inhibitory activity. The capacity of IL-4 to induce inhibitory activity in stromal cell layers suggests that IL-4 may play a role in the regulation of hematopoiesis.     

健康人心室复极的昼夜变化研究

目的 探讨健康人心室复极的昼夜变化规律. 方法 对34例健康体检者的24h动态心电图进行回顾性分析.测定其心率、Q-T间期、QRS波群起点至T波波峰的时间(Q-Tp间期).计算T波波峰至终点的时间(Tp-e时间)、心率校正的Q-T间期(Q-Tc间期)和Tp-e时间(Tp-ec时间)、Tp-e/Q-T值,并比较一天中8个等分时间段的上述参数. 结果 Q-T间期和Tp-e时间呈日间短、凌晨及午夜长的昼夜节律变化,各时间段差异有统计学意义(P<0.01或0.05);Q-T间期与心率呈高度负相关(r=-01796，P<0.01)．而Tp-e时间与心率呈低度负相关(r=-01267，P<0.01)；各时间段Q-Tc间期接近,而Tp-ec时间呈07:00～09:00最高、10:00～12:00次之、01:00～03:00最低的昼夜节律变化,各时间段差异有统计学意义(P<0.05),Tp-e／Q-T值昼夜变化节律与Tp-ec时间相近.结论 反映心室复极跨壁离散度的Tp-e时间除受心率影响外,尚受昼夜节律的影响.     

细胞因子在慢性肝衰竭合并全身炎症反应综合征病例中的意义

目的探讨TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18在慢性肝衰竭合并全身炎症反应综合征(SIRS)中的意义。方法运用双抗体夹心酶联免疫吸附法检测正常人、一般肝炎患者、慢性肝衰竭组的TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18。结果自正常对照组到一般肝炎组、慢性肝衰竭非SIRS组、慢性肝衰竭SIRS组,血清中TNF-α、LPS、IL-12及IL-18水平依次升高,IL-10分子水平依次减低,且各组间比较均具有显著性差异。结论TNF-α、LPS、IL-10、IL-12、IL-18水平可以反应出乙型肝炎患者的肝脏损伤程度和疾病严重程度,可能在慢性肝衰竭合并SIRS的发病过程中起到相当重要的作用。     

湖南省临床艾滋病检测筛查实验室基本情况调查

目的了解各级临床实验室开展HIV血清学筛查试验的情况。方法采用问卷调查方式对141家临床艾滋病检测筛查实验室进行调查,利用Excel表建立数据库并进行分析。结果141家实验室2006年度共检测样本303045份,筛查阳性样本2404份,确认阳性样本276份,筛查阳性检出率和确认符合率分别为0.09%和11.48%。送检样本最多的科室是外、内、急诊和妇儿科。多数实验室采用国产酶联免疫吸附试剂。多数实验室缺少生物安全防护设备。结论进一步加强对实验室的管理,提高检测质量。