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21.
Onnen Grauhan Henryk Siniawski Michael Dandel Hans Lehmkuhl Christoph Knosalla Miralem Pasic Yu-Guo Weng Roland Hetzer 《European journal of cardio-thoracic surgery》2007,32(4):634-638
OBJECTIVE: Due to the shortage of donor hearts, the criteria for organ acceptability have been considerably extended and donor grafts with coronary atherosclerosis are among those offered. This study evaluated whether and to what degree pre-existing coronary atherosclerosis may be acceptable. METHODS: A total of 1253 consecutive HTx recipients were investigated retrospectively for donor-transmitted coronary atherosclerosis (DCAS). Donor-transmitted coronary atherosclerosis was defined as focal atherosclerosis with stenosis of at least 50%. Inclusion criteria were absence of pre-HTx angiogram but performance of angiogram or autopsy within 6 months after heart transplantation. Kaplan-Meier analysis and log-rank test were used. RESULTS: Eighty-five out of 1253 (6.8%) cases were excluded, since coronary evaluation was not performed within 6 months (n=45) or hearts had undergone pre-transplant angiography (n=40). In 1086 patients no donor-transmitted coronary atherosclerosis was found (NDCAS group) and in 82 patients (7%) donor-transmitted coronary atherosclerosis was diagnosed by angiography (n=49) or autopsy (n=33). Single-vessel donor-transmitted coronary atherosclerosis was found in 53/82 patients (DCAS1 group) and double- or triple-vessel donor-transmitted coronary atherosclerosis in 26/82 patients (DCAS2/3 group). Three of the 82 patients with donor-transmitted coronary atherosclerosis were excluded since the autopsy report was unclear regarding degree of atherosclerosis. Early after heart transplantation the 30-day mortality in the NDCAS and DCAS1 groups was 12.2% versus 13.2% whereas in the DCAS2/3 group it was 61.5%. Beyond the first year the annual decrease with and without donor-transmitted coronary atherosclerosis (single-vessel disease) is comparable. CONCLUSIONS: Donor screening without coronary angiogram overlooks significant atherosclerotic lesions in a considerable number of cases (7.0%). Therefore, angiographic donor screening should be performed. Donor grafts with single-vessel coronary atherosclerosis may be accepted as marginal hearts; however, in our opinion, revascularisation (CABG, PTCA) should be considered. Grafts with two- or even three-vessel coronary atherosclerosis seem to have a serious risk for early graft failure. Beyond the first year the outcome of healthy grafts and grafts with donor-transmitted coronary atherosclerosis seems to be comparable. 相似文献
22.
Three rare cases of upper eyelid trauma are presented. In high-speed traffic accidents, the upper eyelids were penetrated by glass, avulsed, and then, together with pieces of glass, pushed over the globe and buried deeply in the retrobulbar area. The invaginated eyelids were pulled out gently, the conjunctiva still attached to the globes. They were repaired primarily. In these patients eyelid function and cosmesis were preserved. 相似文献
23.
纳米技术是20世纪80年代末期兴起的新技术。此种新技术是指在1-100nm这一尺度范围内对原子和分子运动规律和特性进行研究和应用。通过直接操纵和安排原子、分子将物质转变成具有特殊性能的新材料的科学技术。纳米技术研究的最终目标是直接以原子和分子为起点,从纳米材料出发或采用纳米加工技术,制造出具有特殊功能的产品,从而改变人类的生产和生活模式。纳米科技保健产品对促进人类健康有积极作用。 相似文献
24.
Radiologic and pathologic mani;estations of 30
peripheral pulmonary masses around l.5-3 cm in dia-
meter were compared to the pathologic basis of va-
cuole sign and small node sign on tomogram. Stati
stics of 100 conventional X-ray tomograms of peri-
pheral pulmonary masses about l-3 cm in diameter
suggested that the vacuole sign and small node sign,
more common in early peripheral lung cancer than
in tuberculoma, are valuable for differentiating early
peripheral lung cancer from tuberculoma. 相似文献
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宫颈粘液过氧化物酶在月经周期中的变化规律 总被引:3,自引:1,他引:2
本文对29例月经周期正常妇女的宫颈粘液过氧化物酶进行了30个周期的研究。在月经周期不同时间测定宫颈粘液过氧化物酶(CMPx)活性及血清促黄体生成素(LH)、雌二醇(E_2)和孕酮(P)。结果表明:在排卵前三天酶活性明显下降,至排卵后一天开始上升。卵泡期,酶活性与E_2呈负相关(r=-0.67);黄体期,酶活性与P呈正相关(r=0.79)。本研究提示:1.CMPx在排卵周期具有特定的变化规律,其变化受体内激素水平影响,可作为预告排卵的指标。2.如简化测定方法,可为自然避孕提供新途径。 相似文献
28.
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
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The surveillance complex interacts with the translation release factors to enhance termination and degrade aberrant mRNAs
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