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51.
Pirzada OL 《Bulletin of experimental biology and medicine》2002,133(6):574-576
In vivo experiments on rats and rabbits showed that megestrol caproate, a 17-alpha-hydroxyprogesterone derivative exhibits 10-fold higher gestagenic activity compared to progesterone and possesses no androgenic, anabolic, and estrogenic activities. 相似文献
52.
Eric N. Juberg Kenneth P. Minneman Peter W. Abel 《Naunyn-Schmiedeberg's archives of pharmacology》1985,330(3):193-202
Summary The properties of
1- and
2-adrenoceptors in right and left atria of rat heart, and their roles in mediating chronotropic and inotropic responses to-adrenoceptor agonists were examined. [125I](-)-pindolol (125IPIN) bound saturably and specifically to a single class of high affinity sites in homogenates of both right and left atria. Thek
1's for association in right and left atria were 6.5×109 l/mol-min and 2.3×109 l/mol-min respectively, while thek
–1's for dissociation were 0.20 min–1 and 0.17 min–1. The kinetically determinedK
D's were 75 pmol/l in right and 30 pmol/l in left atria and were similar to the equilibriumK
D's determined from Scatchard analysis of saturation isotherms of specific125IPIN binding. Inhibition of125IPIN binding by-adrenoceptor antagonists was stereoselective and the order of potency was timolol > 1-propranolol > d-propranolol > sotalol. Inhibition by
1- and
2-adrenoceptor subtype selective antagonists yielded flat displacement curves with low Hill coefficients. Nonlinear regression analysis of displacement by
1-selective (practolol, atenolol and metoprolol) and
2-selective (ICI 118,551) antagonists gave estimates of the proportion of
1- and
2-adrenoceptors present in rat atria. Right atria contained 67±4.2%
2-adrenoceptors and 33±4.2%
2-adrenoceptor, while left atria contained 67±2.8%
1- and 33±2.8%
2-adrenoceptors. Increases in the rate of spontaneously beating right atria and the force of electrically driven left atria caused by-adrenoceptor agonists were also measured. pA2 values for non-subtype selective-adrenoceptor antagonists in inhibiting isoprenaline-induced increases in rate and force were highly correlated withK
D values determined for specific125IPIN binding. pA2 values for
1- and
2-selective antagonists in inhibiting isoprenaline-induced increases in rate and force correlated well with the pK
D values of these drugs in binding to
1-adrenoceptors, but not with the pK
D values in binding to
2-adrenoceptors. Dose-response curves for stimulation of both rate and force by the
2-selective agonists procaterol and zinterol were shifted to a much greater extent by selective blockade of
1-adrenoceptors with metoprolol than by selective blockade of
2-adrenoceptors with ICI 118,551, suggesting that these compounds caused their effects by activating
1-adrenoceptors. These results suggest that
1- and
2-adrenoceptors coexist in both left and right atria of rat heart in approximately a 21 ratio, however only
1-adrenoceptors mediate the chronotropic and inotropic effects of-adrenoceptor agonists.Supported by a grant from the American Heart Association — Georgia Affiliate 相似文献
53.
PEEP impedes thoracic duct drainage (LF). This can be counteracted by a thoracic duct fistula. Consequently, lung oedema (LOE) should develop during PEEP more slowly with LF at atmospheric pressure (LFAP) than with LF against jugular venous pressure (LFJVP). In 12 anaesthetized dogs LOE was produced by Ringer's solution i.v. (2.5 ml/min per kg) for 6 h during PEEP (10 mmHg) with either LFAP or LFJVP. Ringer's+PEEP greatly increased aortic, pulmonary artery and wedge pressures, JVP, and cardiac output. Colloid osmotic pressures in plasma and lymph were drastically reduced, pulmonary effective filtration pressure (EFP) rose by about 20 mmHg. LFJVP increased 7-fold, LFAP about 19-fold, the respective loss of plasma proteins was 1.83 and 1.06 g/kg during 6 h. Thermal-dye extravascular lung water showed an increment of 68 with LFJVP versus 43 l/h/g per mmHg with LFAP. Final lung water content was at any EFP (12.8–31.9 mmHg) lower with LFAP than with LFJVP amounting 512 with LFJVP versus 377 l/g/per mmHg with LFAP. LFAP decreased the development of LOE during PEEP by bypassing the PEEP-induced high JVP and thus facilitating the removal of interstitial fluid. It is hypothesized that a thoracic duct fistula might aid the treatment of patients with LOE due to ARDS and therefore requiring high levels of PEEP. 相似文献
54.
Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1986,332(4):406-409
Summary The role of sinoatrial 1- and 2-adrenoceptors mediating positive chronotropic effects of (–)-adrenaline and (–)-noradrenaline was investigated in rat right atria. Concentration effect curves for (–)-adrenaline, but not for (–)-noradrenaline, became biphasic in the presence of the 1-adrenoceptors antagonist CGP 20712 A. The curves for (–)-adrenaline in the presence of 300 nmol/l CGP 20712 A (equivalent to 1,000 times its K
B, K
B=0.3 nmol/l for 1-adrenoceptors) comprise a high-sensitivity component that saturates at 1/4 of maximum effect, and a low sensitivity component. The high-sensitivity component is blocked by the 2-adrenoceptor-selective antagonist ICI 118,551. These results are consistent with an involvement in the rat of both 1-adrenoceptors (to a major extent) and 2-adrenoceptors [only at high (–)-adrenaline concentrations] in the positive chronotropic effects of (–)-adrenaline. (–)-Noradrenaline appears to activate mostly rat sinoatrial 1-adrenoceptors. 相似文献
55.
M. Delhaye J. M. De Smet G. Taton P. De Neef J. C. Camus J. Fontaine M. Waelbroeck P. Robberecht J. Christophe 《Naunyn-Schmiedeberg's archives of pharmacology》1984,325(2):170-175
Summary Binding to muscarinic receptors was compared with adenylate cyclase inhibition in membranes derived from human heart auricles, and with inhibition of the contraction of auricular muscle fibers.In the absence of GTP, agonists recognized two classes of receptors both of which bound antagonists with the same affinity. In the presence of GTP, both classes of receptors for agonists were converted into a single low affinity state.Carbachol and oxotremorine inhibited adenylate cyclase activity by 43%, pilocarpine being less efficient (–28%). The 3 agonists exerted similar inhibitory effects on the inotropic response, in 7 out of 9 preparations of electrically- and norepinephrine-stimulated fibers. Dose-effect curves suggested that spareness (or an amplification mechanism) was implicated in the occupancy of low affinity binding sites by carbachol and oxotremorine (but not by the partial agonist pilocarpine) and the resulting inhibition of both adenylate cyclase activity and contractile force.Abbreviations [3H] NMS, [N-methyl-3H]
scopolamine methyl chloride
- Gpp(NH)p
guanosine 5-0-(2-3 imido) triphosphate
- EGTA
ethylene glycol bis (2-aminoethyl ether)-N,N,N,N-tetraacetic acid 相似文献
56.
目的探讨在产科护理教学中应用正常分娩综合性实验教学取得的效果研究。方法选取2018年9月—2019年6月在该院实习120名护理本科生作为研究对象,依据奇数偶数分配原则分为两组,其中对照组60名学生进行常规的消毒操作和外阴清洁考核,观察组的60名学生应用正常分娩综合性实验进行考核,对比两组学生护理技能测试成绩以及取得的教学效果。结果观察组优良率(98.33%)高于对照组(88.33%),差异有统计学意义(P<0.05);观察组团队协作能力、学习兴趣、解决问题能力、沟通能力及操作能力评分高于对照组,差异有统计学意义(P<0.05)。结论产科护理教学中应用正常分娩综合性实验教学取得的效果显著,能提升教学成绩,让实习护理本科生更快掌握护理技巧,为医院输送优质护理人才,能缓解产科护理人员缺乏的现象,正常分娩综合性实验教学方案值得应用。 相似文献
57.
张明 《中国实用乡村医生杂志》2021,(1)
目的探讨自我角色认同护理在躁狂症中的应用效果。方法选取2017-2019年沈阳市铁西区精神卫生中心收治的成人躁狂症发作期患者50例,随机分为对照组和干预组各25例。对照组给予常规护理,干预组给予自我角色认同护理。分别采用激越行为量表和社交技能量表对两组的干预效果进行评价。结果干预后两组激越行为量表和社交技能评定目录量表各维度评分及总分差异均有统计学意义(P<0.05)。结论自我角色认同护理能进一步改善躁狂症患者的激越行为和社交技能,值得临床推广应用。 相似文献
58.
江涛王冰张磊朱靓李晓康 《中国卫生质量管理》2021,(4):039-42
目的探讨多学科协作诊疗在直肠癌手术中的开展成效。方法将进入多学科协作的患者和未进入多学科协作的患者分别设为观察组和对照组,通过多项指标量化分析直肠癌多学科协作开展成效。结果观察组的术后住院时长短于对照组,差异有统计学意义(P<0.05);术后首次下床时间短于对照组,差异有统计学意义(P<0.05);手术总费用、检查费、床位费少于对照组,差异有统计学意义(P<0.05)。观察组低位直肠癌手术有效保肛率高于对照组;在术后早期并发症中,观察组病例数少于对照组;在Ⅲ期直肠癌患者术后无进展生存时间上,观察组要高于对照组,差异有统计学意义(P<0.05)。观察组在生存量表总分、生理领域、心理领域得分均高于对照组,差异有统计学意义(P<0.05)。结论多学科协作在直肠癌诊疗中效果明显,能够确保直肠癌患者手术安全,缩短术后住院时长,降低手术费用,并减少术后并发症发生率,提升低位直肠癌有效保肛率,延长Ⅲ期直肠癌患者术后无进展生存时间,改善患者生存质量。 相似文献
59.
Daniel T.L. Shek Li Zhao Diya Dou Xiaoqin Zhu Chenghan Xiao 《The Journal of adolescent health》2021,68(4):676-682
PurposeThis study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.MethodsFive schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.ResultsA total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = ?.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.ConclusionsThis study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs. 相似文献
60.
目的 对东营区≥45岁常住居民进行结直肠癌筛查,并探讨初筛阳性者肠镜顺应性及其影响因素,为提高居民结直肠癌筛查工作提供科学依据。方法 采用方便抽样方法选择辖区内2个镇和3个街道的社区卫生服务中心作为结直肠癌筛查志愿者招募点招募≥45岁常住居民为研究对象开展结直肠癌筛查及问卷调查,对初筛阳性者进一步进行肠镜检查,采用描述性分析方法对居民结直肠筛查结果及肠镜顺应性进行分析,并对其影响因素进行单、多因素分析。结果 本研究共纳入1 201人进行分析,男662人,女539人,45~59岁372人,60~69岁495人,70~79岁334人。初筛阳性人数总计371例,其中危险因素初筛阳性154例,FOBT阳性298例,危险因素和FOBT阳性双阳性者81例,初筛阳性率为30.89%。男性(OR=3.177)、黏液血便史(OR=7.683)以及肠道息肉病史(OR=5.008)为结直肠癌初筛阳性的危险因素。371例初筛阳性者中121例完成结肠镜检查,结肠镜检查顺应率为32.61%。性别(OR=2.776)、年龄(OR=0.511、0.433)、婚姻状况(OR=4.267)、文化程度(OR=2.782、3.916)、医疗保险(OR=2.743)是结直肠癌初筛阳性者结肠镜检查顺应性的影响因素。结论 东营市东营区结直肠癌初筛阳性率较高,应加强对存在黏液血便史以及肠道息肉病史男性个体人群的结直肠癌筛查。居民结直肠镜检查顺应性较低,尤其是60岁及以上、非在婚、文化程度较低、无医保的女性个体,可特异性强化对该群体个体的健康教育,提高其结直肠镜顺应性。 相似文献