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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
211.
212.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献
213.
D. A. Stewart D. Guo J. A. Sutherland B. A. Ruether A. R. Jones M.-C. Poon C. deMetz J. Klassen A. Chaudhry C. B. Brown J. A. Russell 《Annals of oncology》1997,8(12):1277-1279
Background: Few data are available on the cost, safety, and long-termefficacy of single agent high-dose melphalan (HDM) followed by autologousbone marrow (ABMT) or blood stem cell (ABSCT) transplantation in the salvagetherapy of Hodgkins disease (HD).Patients and methods: From February 1981 to September 1996, 23 patientswith relapsed (n = 15) or refractory (n = 8) HD received salvage therapywith HDM 140–200 mg/m2 followed by non-cryopreservedABMT (n = 18) or cryopreserved ABSCT (n = 5). The cost of HDM/ABSCT in 1996,from initial consultation until transfer back to referring physician, wasdetermined and compared to the estimated costs of two multi-agent regimenscommonly used for HD.Results: HDM was well tolerated with no early transplant-relatedmortality. The five-year overall and progression-free survival rates were52% and 50%, respectively. The average total cost in Canadianfunds of HDM/ABSCT in 1996 was $34,400/patient. This cost wasestimated to be $4,700–6,800 cheaper per patient than themulti-agent high-dose regimens.Conclusion: These data suggest that HDM is safe, feasible, active, andreasonably inexpensive salvage therapy for patients with relapsed/refractoryHD. 相似文献
214.
Purification of thrombospondin from human platelets 总被引:1,自引:0,他引:1
Summary Thrombospondins are a rapidly growing family of adhesive proteins that have diverse activities to modulate cellular growth, motility, and gene expression. Thrombospondin-1 (TSP) was the first identified member of this family and is the major form of thrombospondin in human platelets. A method is described to prepare TSP from human platelets in biologically active form with minimal degradation or contamination with other platelet proteins. 相似文献
215.
N. Singewald F. Chen L. J. Guo A. Phillippu 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(6):620-625
The push-pull technique was used to investigate the release of the excitatory amino acid glutamate in the posterior hypothalamic area of the conscious rat. The hypothalamus was superfused through the pushpull cannula with artificial cerebrospinal fluid (CSF), and the superfusate was collected in time periods of 10 min when ionic conditions in the CSF were changed, or in short periods of 3 min when blood pressure changes were evoked. The mean glutamate release rate was 2.8 + 0.7 pmol/min. Depolarization by hypothalamic superfusion with CSF containing 50 mM K+ enhanced the release of glutamate in the presence of Ca2+. The K+-induced release was attenuated by 40% when the hypothalamus was superfused with Ca2+-free CSF. Replacement of Ca2+ by Mg2+ abolished the K+-induced release of glutamate. Hypovolaemia elicited by haemorrhage enhanced the release rate of glutamate. Similarly, a hypotension elicited by i.v. injection of chlorisondamine (3 mg/kg) led to a pronounced and permanent enhancement in glutamate release. The effects of hypovolaemia and chlorisondamine on glutamate release were abolished in aortic denervated rats, indicating that this response is due to a decrease of impulse generation in baroreceptors. A hypovolaemia elicited by blood infusion did not affect the release of glutamate. Similarly, a pronounced pressor response to phenylephrine (15 /kg per minute) infused intravenously for 9 min was ineffective.The results show that the K+-induced release of glutamate in the hypothalamus is dependent on the presence of Ca2+. The increase in glutamate release rate by hypovolaemia or chlorisondamine suggests that the glutamatergic neurons in the posterior hypothalamic area respond to unloading of aortic baroreceptors and possess a counteracting, hypertensive function. 相似文献
216.
目的 探讨上海市≥50岁人群维生素D水平与握力的关系。方法 数据来源于WHO全球老龄化与成人健康研究我国上海市2018-2019年数据,采用logistic回归模型分析维生素D水平与握力的关系,进一步按照性别、年龄及乳制品摄入情况进行分层;采用限制性立方样条曲线绘制维生素D水平与低握力的剂量-反应曲线。结果 共4 391人纳入研究,其中男性2 054人(46.8%);年龄(67.02±8.81)岁;低握力1 421人(32.4%);维生素D不足及缺乏分别为1 533人(34.9%)和401人(9.1%)。在调整相关混杂因素后,logistic回归分析结果显示,维生素D缺乏的人群发生低握力的风险更高(OR=1.41,95%CI:1.09~1.83);在男性中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.67,95%CI:1.12~2.50),而女性中两者之间无关联(OR=1.30,95%CI:0.97~1.74);在60~69岁及≥80岁年龄组中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.57,95%CI:1.05~2.35;OR=2.40,95%CI:1.08~5.31),在乳制品摄入<250 ml/d的人群中,调整相关混杂因素后,二者之间呈显著正相关(OR=1.57,95%CI:1.17~2.09),而在乳制品摄入≥250 ml/d的人群中无明显关联。限制性立方条样图显示,低握力的发生风险可能随维生素D含量的上升而降低,但差异无统计学意义(P>0.05)。结论 维生素D水平与握力存在一定的关系,维生素D缺乏人群出现低握力的风险更高。 相似文献
217.
从粤东丰溪自然保护区白腹巨鼠和褐家鼠体内分离出莱姆病螺旋体 总被引:3,自引:1,他引:2
目的:探讨鼠类携带莱姆病螺旋体情况。方法:用BSK培养基分离病原、单克隆抗体鉴定。结果:从白腹巨鼠和褐家鼠体内分离出2株疏螺旋体,经用莱姆病螺旋体种属特异的单克隆抗体进行间接免疫荧光抗体试验,证实均为莱姆病螺旋体,命名为MD21和MD55。结论:首次从病原学证实鼠类为粤东地区莱姆病螺旋体的主要宿主动物。 相似文献
218.
目的了解和掌握江湾地区婴儿体格发育状况。方法对江湾地区1996年1月~1997年9月出生的217名婴儿(男114名,女103名)体重、身长进行系统监测至12个月,其实际测量均值与WHO国际参照值作比较。结果江湾地区婴儿(无论男女)体重、身长在各年龄组均达到或高于WHO国际参照值。结论江湾地区婴儿体格发育状况良好。 相似文献
219.
经鼻(面)罩机械通气治疗慢性阻塞性肺疾病呼吸衰竭 总被引:3,自引:0,他引:3
目的观察慢性阻塞性肺疾病(COPD)呼吸衰竭患者经鼻(面)罩机械通气的效果。方法对29例慢性阻塞性肺疾病呼吸衰竭患者行经鼻(面)罩机械通气。结果治疗后2小时、24小时、48小时、1周后,pH从7.28±0.1上升至7.34±0.07、7.35±0.06、7.38±0.05、7.37±0.07(P<0.01),PaCO2从94.69±18.4mmHg下降至86.05±24.6mmHg(P<0.01)、77.76±19.3mmHg(P<0.01)、68.60±11.4mmHg(P<0.001)、66.69±26.9mmHg(P<0.001),PaO2从52.72±13.1mmHg上升至64.25±24.5mmHg(P<0.05)、69.01±16.6mmHg(P<0.002)、75.27±32.8mmHg(P<0.001)、91.16±40.4mmHg(P<0.001)。临床症状明显改善,有效率75.9%。结论经鼻(面)罩机械通气对轻、中度的患者有较好的疗效。 相似文献
220.