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61.
(1)目的 总结探讨11例非体外循环冠状动脉搭桥术(OPCAB)的经验。(2)方法 2001年6-12月对11例冠心患采用非体外循环心脏不停跳方法完成冠状动脉搭桥术。(3)结果 共搭桥35支,平均3.17支/例,其中左乳内动脉桥8支,大隐静脉桥27支。6例患(54.5%)未血,无手术死亡及并发症。(4)结论 非体外循环搭桥术克服了体外循环搭桥术(CABG)的诸多缺点和弊端,手术简化,时间缩短,适应证扩大,并发症明显减少,效果满意。 相似文献
62.
4种头孢菌素的抗生素后效应影响因素 总被引:4,自引:0,他引:4
目的:研究头孢呋辛(CXM)、头孢噻肟(CTX)、头孢哌酮(CPZ)、头孢地嗪(CDZM)的抗生素后效应及药物浓度、接触时间、菌种等因素的影响。方法:采用AVANTAGE全勇自动微生物分析仪、用光密度法测定4种抗生素不同浓度对2种共12株临床常见致病菌不同反应时间的体外抗生素后效应(PAE)。结果:4种头孢菌素类药物对革兰阳性球菌有较明显的PAE,对革兰阴性杆菌PAE较小甚至没有或为负值;药物浓度 相似文献
63.
Serotonin (5-HT) may be inhibitory to micturition at a spinal level. A potential mechanism of action for serotonergic inhibition of bladder function is a depression of the ascending limb of the supraspinal reflex mediating micturition. Ascending activity evoked by pelvic nerve stimulation was recorded in the thoracic spinal cord of anesthetized cats. For comparison, spinal reflex activity evoked by pelvic nerve stimulation was recorded on the pudendal nerve. The effects of intrathecal administration of serotonergic agents were examined to determine whether spinal and supraspinal responses to bladder afferent activation were modulated by 5-HT. Methysergide (60 nmol), a non-selective serotonergic antagonist, increased ascending activity by 61±7% and depressed spinal reflex activity by 38±6%. Zatosetron (10 nmol), a 5-HT3 antagonist had a similar effect on both activities (increased by 93±24% and decreased by 77±7%, respectively). The effect on ascending activity of blocking 5-HT3 receptors was also confirmed with ICS 205930 and MDL 72222. 2-Methyl-5-HT (800 nmol), a 5-HT3 agonist, depressed ascending activity to 46±9% of control, but enhanced spinal reflex activity by 73±92%. These results demonstrate that stimulation of 5-HT3 and methysergide-sensitive 5-HT receptors can inhibit ascending activity and facilitate spinal reflex activity elicited by activation of bladder afferents. It is suggested that descending serotonergic pathways may participate in the spinal coordination of urinary continence. 相似文献
64.
IUD对子宫收缩的影响观察 总被引:6,自引:3,他引:3
本文重点研究妇女正常月经净后七天之内子宫收缩压力和频率,以及频脱器妇女与第一次置器妇女子宫收缩压及其相互间的差别。结果:(1)23例妇女月经净后七天之内子宫收缩压力为2.21~14.14mmHg/次,均值7.66±2.89mmHg/次。10分钟内子宫收缩28~76次,均值4.51±1.14次/分;(2)第一次置器妇女与频脱器妇女其置器前、后子宫收缩压力大小无显著差异(P>0.05)(3)子宫腔内有器子宫收缩压力比子宫腔内无器时大。两组子宫收缩压力t 检验结果(P<0.05)有显著差异:(4)第一次置(取)器前、后当时子宫收缩压力及频率大小皆有显著差异(P<0.05)。置(取)器后子宫收缩压力比置(取)器前大;(5)频脱组在置器前、后当时子宫收缩压力大小有显著差异(P<0.05),与第一次置器组相同;(6)本法测试子宫收缩压力达37~62mmHg/次时,部分受术者即有明显的下腹痛或痛感较强。 相似文献
65.
杜康宁 《中国脊柱脊髓杂志》1988,(4)
本文讨论用“包络一轨迹”法设计的修正齿形链的传动特性,并提出了完善齿形修正设计的方法,基本上实现消除链传动申的“多边形效应”。 相似文献
66.
消化道肿瘤免疫相关不良事件的临床分析 《首都医科大学学报》2023,44(2):343-350
目的探讨消化系统恶性肿瘤中免疫检查点抑制剂(immune checkpoint inhibitors, ICIs)导致免疫相关不良事件(immune-related adverse events, irAEs)的特征及危险因素。方法 回顾性分析2019年4月至2021年10月北京大学肿瘤医院诊治的95例接受ICIs治疗的消化系统恶性肿瘤患者的临床资料和irAEs发生情况。irAEs、内分泌irAEs危险因素分析采用二元Logistic回归分析。结果 95例患者共应用ICIs治疗458例次,中位应用3例次(范围:1~33例次)。irAEs的发生率为55.8%,3~4级irAEs发生率为9.5%。最常见的irAEs为皮肤irAEs(27.4%)和内分泌irAEs(22.1%)。内分泌irAEs中甲状腺功能减退最常见(16.8%),肾上腺皮质功能减退(2.1%)和垂体炎(1.1%)少见。多数irAEs发生于免疫治疗初期,78.2%发生于12周内。过敏反应、皮肤irAEs最早发生,中位发生时间分别为2周(范围:0.9~3.1周)和3.8周(范围:0.9~17.9周),内分泌irAEs中位发生时间为6.9周(范围:3.0~52.1周)。多因素分析显示,女性(OR=5.197, 95%CI:1.166~23.154, P=0.031)和微卫星高度不稳定(microsatellite instability-high,MSI-H) (OR=35.048, 95%CI:2.756~445.787, P=0.006)是内分泌irAEs发生风险增加的独立危险因素,免疫治疗联合化学药物治疗(OR=0.107, 95%CI:0.021~0.412, P=0.001)是内分泌irAEs的独立保护性因素。结论在消化系统恶性肿瘤中应用ICIs具有较好的安全性。女性和MSI-H患者出现内分泌irAEs风险增加,联合化学药物治疗可能降低内分泌irAEs发生风险。 相似文献
67.
68.
Preparation and characterization of porous beta-tricalcium phosphate/collagen composites with an integrated structure 总被引:11,自引:0,他引:11
Porous beta-tricalcium phosphate (TCP)/collagen composites with different beta-TCP/collagen weight ratio were prepared. The influences of the preparation conditions on the microstructure of porous composite and the joint status of beta-TCP particles with collagen fibrils were characterized by X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The results showed: (1) an acid treatment could effectively disassemble collagen fibrils; (2) in the resulting porous composites, beta-TCP particles homogenously existed on the skeleton of the collagen fibril network and bonded tightly to both the fibrils and themselves. The tight bonding formation could be due to the reaction between Ca ions in the particles and carboxyl groups in collagen polypeptide chains and due to the reprecipitation of partially dissolved beta-TCP during synthesis. The tight bonding between beta-TCP particles and collagen fibrils in the composites demonstrated an integrated structure, which was reproducible when beta-TCP/collagen ratio ranged from 2 to 4. Such integrated structure would make significant contributions in reliably tailoring properties of the porous composites by varying beta-TCP content. In addition, the porous composites had large porosity (approximately 95%) and appropriate pore size (approximately 100 microm), showed no negative impact in cytotoxicity assay and complete bone tissue regeneration after 12 weeks in animal test. 相似文献
69.
Alpha-smooth muscle actin as a marker for soft tissue tumours: a comparison with desmin 总被引:1,自引:0,他引:1
The immunoreactivity of a range of vascular and non-vascular smooth muscle tumours, rhabdomyosarcomas, and non-myoid lesions has been examined with the use of a monoclonal antibody to smooth muscle-specific actin and the muscle intermediate filament, desmin. In all cases of smooth muscle-derived tumours, the alpha-actin antibody yielded superior results. Staining of the myofibroblasts of fibromatoses was also seen. In contrast to desmin, immunoreactivity was not exhibited by rhabdomyosarcomas. We propose that this monoclonal antibody to alpha-smooth muscle actin is a useful addition to the panel of reagents used for the characterization of soft tissue proliferations and tumours. The technical aspects of the application of this monoclonal antibody to immunohistochemistry are discussed. 相似文献
70.
A novel active L1 retrotransposon subfamily in the mouse 总被引:8,自引:1,他引:8
Unlike human L1 retrotransposons, the 5' UTR of mouse L1 elements contains tandem repeats of approximately 200 bp in length called monomers. Multiple L1 subfamilies exist in the mouse which are distinguished by their monomer sequences. We previously described a young subfamily, called the T(F) subfamily, which contains approximately 1800 active elements among its 3000 full-length members. Here we characterize a novel subfamily of mouse L1 elements, G(F), which has unique monomer sequence and unusual patterns of monomer organization. A majority of these G(F) elements also have a unique length polymorphism in ORF1. Polymorphism analysis of G(F) elements in various mouse subspecies and laboratory strains revealed that, like T(F), the G(F) subfamily is young and expanding. About 1500 full-length G(F) elements exist in the diploid mouse genome and, based on the results of a cell culture assay, approximately 400 G(F) elements are potentially capable of retrotransposition. We also tested 14 A-type subfamily elements in the assay and estimate that about 900 active A elements may be present in the mouse genome. Thus, it is now known that there are three large active subfamilies of mouse L1s; T(F), A, and G(F), and that in total approximately 3000 full-length elements are potentially capable of active retrotransposition. This number is in great excess to the number of L1 elements thought to be active in the human genome. 相似文献