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31.
20世纪中医药学的多学科研究概述 总被引:4,自引:0,他引:4
回顾性分析20世纪中医药学的多学科研究概况,以新中国成立为界分为前后两个阶段,通过对相关资料及文献的综合分析,认为中医药学的发展在很长时间内呈现一脉相承的特点,20世纪初,随着中西医汇通思潮的兴起,客观上促进了中医药多学科研究的发展,近50年的中医药多学科研究,尤其是近20年的多学科渗透,更进一步带动了中医药多学科研究的发展。 相似文献
32.
目的 探索多层螺旋CT作肺血管分期造影的可能性和评价肺癌侵犯中央肺动脉的临床价值。方法 用多层螺旋CT对73例肺门区肺癌患者进行研究。分两段对比剂注射,结合三个扫描程序作肺血管分期造影,根据肺动脉被侵犯的不同部位和程度分为三度。按盲法评价图像并与手术和病理对照。结果 肺动脉分期造影成功的共68例(93.15%,68/73)。肺动脉I度侵犯者4例(5.88%,4/68),Ⅱ度侵犯者9例(13.23%,9/68),Ⅲ度侵犯者55例(80.88%,55/68)。I度者全部作肺叶切除;Ⅱ度与Ⅲ度者的肺叶切除率有显著性差异(x^2=64.03,P<0.005);Ⅲa度与Ⅲb度者的肺叶切除率也有显著性差异(x^2=68.69,P<0.005),Ⅲc度全部放弃手术。结论 多层螺旋CT作肺血管分期造影能更好地显示肺癌侵犯中央肺动脉的部位和程度,为选择外科治疗方案提供更多的影像学依据。 相似文献
33.
目的探讨肺动脉栓塞多排螺旋CTA血管成像扫描延迟时间的最佳值,最佳肺动脉血管成像。方法收集了45例肺动脉栓塞多排螺旋CTA血管成像,造影剂用量按1.5ml/kg,注射速率3ml/sec。扫描延迟时间用Bolus Tracking第一组20例;test Bolus为二组15例;常规计算时间为一组10例。准直器宽度2.5mm,层厚3mm。数据重建用最大密度投影(MIP)和容积显示(VR3D)等常规方法。一、二、三组图像分别由两位高年资医师阅片。结果第一组20例中19例和第二组15例图像肺动脉均清晰显示。第三组10例中4例图像模糊,第三组与第一、二组图像质量有显著差异。结论肺动脉栓塞CTA血管造影中扫描延迟时间用Test Bolus和Bolus Tracking较优,常规计算时间延迟图像质量较差。 相似文献
34.
目的:以商售 Charm 细菌四环素族受体与四环素族的特异性结合反应为基础,应用其对活体禽类动物血清中四环素族抗生素残留总量进行快速筛选,重点对方法的灵敏度、选择性、基质影响和准确性等进行综合评价。方法:血清经缓冲液稀释,其中的四环素族抗生素残留与~3H 标记的金霉素竞争结合特异性细菌受体。竞争反应温育时间5 min,温度35℃。3300r·min~(-1),5 min 离心分离倾去未结合的游离化合物,复合物沉淀用水溶解,加入闪烁液混匀后放置1 min,进行[~3H]通道的60s 液体闪烁计数。结果:在大于95%的置信水平,血清中四环素、土霉素和金霉素的检测低限分别为80,55,15μg·L~(-1);样本测试表明筛选水平为200μg·L~(-1)时,假阴性率为0,阳性检出结果中假阳性率不超过15%。结论:与色谱法相比,其快速、灵敏、选择性高,可对活体禽类动物血清中四环素族残留物进行高通量筛选。 相似文献
35.
多酶微片胶囊中胃蛋白酶的活力测定 总被引:3,自引:0,他引:3
目的:建立多酶微片胶囊中胃蛋白酶活力测定的方法.方法:利用胃蛋白酶作用于底物血红蛋白,酶解生成不被三氯醋酸沉淀的小分子肽和氨基酸,并以酪氨酸为对照,在275 nm波长处测定吸收度.结果:胃蛋白酶平均回收率为101.6%,RSD为1.79%(n=9).结论:本法便捷,准确可靠,重现性好,可用于多酶微片胶囊中胃蛋白酶活力的测定. 相似文献
36.
复方桉叶油素缓释驱避剂的研制 总被引:2,自引:1,他引:2
目的研制高效驱避剂.方法在实验室筛选最佳配方,然后在野外进行效果评价.结果涂擦复方桉叶油素缓释驱避剂后,在14 h内对蚊的驱避率为100%;10 h内对蠓的驱避率为100%,11h后为92.8%,14 h后为82.6%.结论复方桉叶油素缓释驱避剂对吸血昆虫具有很好的驱避效果. 相似文献
37.
38.
目的:观察大黄煎剂保留灌肠联合西药治疗肝性脑病疗效。方法:使用随机平行对照方法,将164例住院患者按抽签方法随机分为两组,对照组62例,给予西医综合治疗。治疗组102例,加用大黄煎剂(醋大黄30 g,乌梅30 g,川朴15 g)水煎200 mL,2剂/d,早晚灌肠,西药治疗同对照组。均连续治疗7 d为1个疗程。观察临床症状,苏醒时间,扑翼样震颤消失时间,血氨水平,肝功能指标,数字连接实验(NCT)及SF-36生活质量表。连续治疗1疗程,判定疗效。结果:治疗组显效54例,有效40例,无效8例,总有效率92.16%。对照组显效27例,有效23例,无效12例,总有效率80.65%。治疗组疗效优于对照组(P<0.05);治疗组的苏醒时间和扑翼样震颤消失时间明显短于对照组(P<0.05);血氨及肝功能两组均有改善(P<0.01),治疗组改善优于对照组(P<0.01,P<0.05);NCT及SF-36生活质量表评分两组均有改善(P<0.01,P<0.05),治疗组改善优于对照组(P<0.05)。均无明显不良反应。结论:大黄煎剂灌肠联合西药治疗肝性脑病疗效显著,值得推广。 相似文献
39.
介绍多目标优化技术在中药复方药物筛选及组方优化中的应用,阐述了多目标优化技术在中药复方研究应用的思路与方法。其方案是以均匀设计法安排实验,综合主要目标法、虚拟目标法和约束条件法等多目标优化方法,以网格法作为优化算法实现复方药物筛选及优化,使多项药效指标都达到较好的平衡,从而取得最佳复方配伍组合。本研究探索建立的基于均匀设计的多目标优化技术在药物复方研究中的应用,有助于解决中药复方药物配伍研究方法的关键技术问题,有助于释放出中药复方中潜在的巨大经济效益。 相似文献
40.
Ling Zhu David B. Grusky 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
In the early 1970s, the balkanization of the US labor market into “men’s occupations” and “women’s occupations” began to unravel, as women entered the professions and other male-typed sectors in record numbers. This decline in gender segregation continued on for several decades but then suddenly stalled at the turn of the century and shows no signs of resuming. Although the stall is itself undisputed, its sources remain unclear. Using nearly a half-century of data from the General Social Survey, we show that a resurgence in segregation-inducing forms of intergenerational transmission stands behind the recent stall. Far from serving as impartial conduits, fathers are now disproportionately conveying male-typed occupations to their sons, whereas mothers are effectively gender-neutral in their transmission outcomes. This segregative turn among fathers accounts for 47% of the stall in the gender segregation trend (between 2000 and 2018), while the earlier integrative turn among fathers accounts for 34% of the initial downturn in segregation (between 1972 and 1999). It follows that a U-turn in intergenerational processes lies behind the U-turn in gender segregation.In all late-industrial countries, women and men continue to occupy very different types of jobs, with women concentrated in service and nurturing occupations (e.g., sales clerk and nurse) and men concentrated in manual and analytic occupations (e.g., laborer and computer scientists). The standard sociological account of such segregation treats it as a premodern relic that should gradually disappear as educational opportunities are equalized, egalitarian gender attitudes diffuse, overt and covert forms of employer discrimination are rooted out, and family-friendly workplaces and related labor market reforms are instituted (1, 2). Between 1970 and 1990, these types of institutional reforms indeed seemed to be bearing fruit, with most late-industrial countries experiencing sharp declines in segregation (3).This egalitarian turn proved to be short-lived. By the end of the 20th century, the decline in gender segregation had stalled in many late-industrial countries, including the United States (4–7). In Fig. 1, we present the US trend using the General Social Survey (GSS), the main data source for our analyses (8). The trend lines in Fig. 1 reveal that the downturn stalled well before integration was achieved (and Fig. 1B additionally suggests a resegregative uptick off this already high baseline). To completely eliminate segregation, ∼60% of US workers would have to shift to a different occupation, a stark result given the stated commitment to gender equality and equal opportunity in the United States. This hypersegregation translates into profound gender gaps in pay, authority, working conditions, and much more (9–12). Because occupational segregation generates such a wide range of unequal outcomes, it has become a conventional policy target among those who seek to reduce gender inequality.Open in a separate windowFig. 1.The U-turn in occupational gender segregation shown by (A) the index of dissimilarity and (B) a margin-free measure of the gender-by-occupation association. Analysis is based on the 1972 to 2018 GSS using women and men in the labor force, ages 25 to 64 (inclusive), with nonmissing data on age, gender, and occupation. n 44,640. Occupations are coded with 1970 Census Occupational Classification (see SI Appendix, Appendixes B and D, for details). Trend is smoothed with locally smoothed regression (LOESS) with the span set at 0.75. For the definition of D and A, see Materials and Methods.The long line of research on the sources of the stall proceeds in part from this widely shared (albeit not universal) commitment to reduce gender inequality. Although far from conclusive or exhaustive, the available research suggests that 1) the persisting double burden of domestic work erodes the willingness or capacity of women to hold jobs that entail long hours or overwork (12–14); 2) the persistence of norms against women outearning their partners (in marriages between women and men) leads to settling and underachievement (15); 3) the persistence of essentialist beliefs about the types of occupations that women and men are qualified to undertake locks in a conventional division of labor (1, 16, 17); and 4) the continuing tendency of employers to discriminate against mothers (18) and those who participate intermittently in the labor force (19, 20) makes it difficult for women to break into male-typed occupations.* Across these assorted supply-side and demand-side accounts, a common theme is that the easy desegregative gains have been creamed off, that a new equilibrium or natural rate (22) has been reached, and that puncturing this equilibrium may require different or more aggressive countermeasures.This interpretation rests on a distinction between 1) overt and easy-to-attack inequalities and 2) covert and difficult-to-attack inequalities. It is often argued, for example, that overt forms of hiring discrimination against women can be reduced through antidiscrimination law and open hiring practices, whereas subtler or covert forms are not as easy to address, at least with legal remedies. Likewise, the extreme essentialist view that women are utterly lacking in rational faculties was an early casualty of the gender revolution, whereas it has proven more difficult to root out a subtler form of essentialism that presumes that men are more likely than women to be “brilliant” or “geniuses” (23). By this logic, the gender revolution will only be reenergized by developing new interventions that are fine-tuned for the subtler, albeit still very consequential, mechanisms that lie behind gender inequality.This conclusion may well be warranted. It would, however, be premature to adopt this interpretation without a fuller understanding of the institutional sources of the stalling out. It is striking in this regard that none of the foregoing accounts directly features the role of intergenerational processes. To be sure, conventional accounts routinely invoke the segregative effects of gender-biased training, norms, and culture, but the social processes through which gender-biased training is delivered or gender-biased norms and culture are instilled are left unclear and thus may or may not have intergenerational sources. This is an unfortunate omission because it undermines our capacity to remediate well. As it stands, most currently popular interventions do not target intergenerational processes (24), an understandable state of affairs given that relatively little is now known about their role in the stalling out.There is, then, a worrying omission in our research on the gender U-turn. Although this omission might seem surprising, it has to be remembered that the contemporary family is often seen as a prime carrier of new forms of gender egalitarianism and accordingly an unlikely source of the stalling out. The new gender-egalitarian family features mothers who are increasingly likely to work, to commit to bona fide careers, and to espouse liberal attitudes (25). In this conventional characterization of familial change, it is notable that mothers are represented as a main force for change, whereas fathers remain in the background largely carrying on. This raises the possibility that fathers may not always be unfettered agents of egalitarian change and may, to the contrary, be implicated in the stalling out. The purpose of our paper is to explore this segregative-father hypothesis by melding models of segregation and intergenerational transmission.The results will show that the U-turn in the segregation trend is indeed linked to a U-turn in intergenerational processes. As we will discuss, a variety of mechanisms may lie behind the rise of segregative reproduction, yet most of them involve familial processes in some fashion. It follows that insofar as desegregation is a policy objective, it may be strategic to build interventions that address contemporary family processes.The two streams of mobility research upon which our analysis will capitalize are those examining 1) the net effects of mothers and fathers on outcomes and 2) the effects of intragenerational mobility on segregation. The first of these two streams is of course especially relevant when examining the intergenerational sources of segregation (26, 27). In recent decades, there has been a backlash against treating the father’s or “family head’s” occupation as a satisfactory measure of class origins (28), a long-overdue development given that a rising share of children are now growing up in more complicated families with many potential role models (29, 30). This newer line of multiple-parent mobility research has, however, focused mainly on examining the relative size of the effects of mothers and fathers, a type of “horse race” analysis that comes naturally when one seeks to rectify decades of scholarship that ignored mothers altogether. As important and influential as this research is, it cannot directly answer the research question that we are taking on, given that the implications of this horse race for occupational segregation depend on the extent to which class and gender-typing reproduction come together. To understand how intergenerational transmission contributes to gender segregation, we need to know 1) whether mothers are passing on female-typed occupations disproportionately to daughters and 2) whether fathers are passing on male-typed occupations disproportionately to sons. Although the intergenerational transmission of gender-typed aspirations is well understood (31, 32), our research takes the next step of building gendered mobility models that uncover whether actual reproductive practices are affected by the gender of the parent, the gender typing of the occupation, and the gender of the offspring (33).The second stream of mobility research relevant to our analysis examines the effects of intragenerational mobility on gender segregation (34). This line of research, which has a long history (35), examines how women and men move in and out of the labor force over their career, how women and men move in and out of gender-typed occupations over their career, and how such mobility has gendered sources (e.g., sexual harassment, gender discrimination, and the “second shift”). Within this literature, many scholars (36) have examined whether the gender of managers affects hiring and promotion decisions (and hence downstream segregation), a line of questioning that is formally similar to our own interest in whether the gender of the parent affects occupational outcomes. Because parents are engaged in ongoing socialization, aspiration development, human capital investment, and network provisioning, their effects on segregation may well be more consequential than the pinpoint hiring and firing decisions of managers. This is the core rationale for building intergenerational processes into a segregation trend analysis. 相似文献