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排序方式: 共有3493条查询结果,搜索用时 15 毫秒
81.
82.
Yehya Amin Davis Jonathan D. Sauer Andrew J. Ibrahim Nasrien E. 《Heart failure reviews》2022,27(3):991-991
Heart Failure Reviews - 相似文献
83.
Hirschburger M Sauer S Schwandner T Schief W Kuchenbuch T Zoerb C Janssen H Grau V Stertmann W Rau WS Padberg W 《The Thoracic and cardiovascular surgeon》2008,56(2):106-109
BACKGROUND: Video-assisted thoracoscopic surgery (VATS) for pulmonary nodules close to the visceral pleura is an established procedure. Different methods have been developed to mark these nodules when resecting small nodules distant to the pleural surface. The possibility of tumor cell spread due to nodule penetration is a major drawback. Furthermore, guide wire-based marking systems have revealed the problem of accidental wire dislocation prior to resection. METHODS: In this study, a new marker system for computed tomography-guided extranodular spiral fixed wire marking (ESFWM) was evaluated in an attempt to maintain tumor integrity while reducing the risk of wire dislocation. RESULTS: Our study included 42 patients with 44 marked nodules. 40 nodules were resected by VATS in 38 of these patients. The remaining 4 patients required conversion to thoracotomy due to adhesions and a non-deflated lung. Wire dislocation and nodule penetration occurred only once. CONCLUSION: The new lung marker system revealed a very low risk of wire dislocation. Peritumoral marking allows the safe resection of subpleural nodules without a risk of tumor cell spread. 相似文献
84.
LaPorte RE Sauer F Dearwater S Sekikawa A Sa ER Aaron D Shubnikov E 《The Lancet infectious diseases》2001,1(2):125-127
Approaches towards the public-health prevention of bioterrorism are too little, and too late. New information-based approaches could yield better homeland protection. An internet civil defence is presented where millions of eyes could help to identify suspected cases of bioterrorism, with the internet used to report, confirm, and prevent outbreaks. 相似文献
85.
Zusammenfassung Die intravenöse Verabreichung von SV 40-Virus-Suspension an schwangere BD IX-Ratten in der ersten bzw. zweiten Hälfte der Tragzeit führte weder zu teratogenen noch zu carcinogenen Wirkungen bei der Nachkommenschaft.Die Untersuchungen mit onkogenen Viren (SV 40) an Ratten werden im Vergleich zur menschlichen Situation diskutiert.
Absence of teratogenic and carcinogenic effects of SV 40-virus in BD-IX rats on application during pregnancy
Summary Intravenous injection of a suspension of SV 40 virus to pregnant BD IX rats in the first or second half of pregnancy did not induce teratogenic or carcinogenic effects in the progeny.The experiments in rats with oncogenic viruses (SV 40) will be discussed in comparison to the human situation.相似文献
86.
87.
Joshua M Cooper William H Sauer Fermin C Garcia Michael J Krautkramer Ralph J Verdino 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2007,9(2):137-142
AIMS: Integrated bipolar implantable cardioverter-defibrillator (ICD) leads use the distal high-voltage coil as both the ventricular sensing anode and the distal shocking electrode. Mechanical interactions between the distal ICD coil and other intracardiac leads have been reported to result in electrical oversensing and inappropriate ICD therapies. We sought to determine whether covering sleeves over the high-voltage coils of an integrated bipolar ICD lead could prevent sensed artefact from mechanical lead interactions. METHODS AND RESULTS: Endotak Reliance 0157 and Endotak Reliance-G 0185 leads, the latter with expanded polytetrafluoroethylene (ePTFE) sleeves covering the high-voltage coils, were connected to ICD generators and the leads were submerged in saline. Device programmers were used to communicate with the ICD generators, providing real-time electrogram recording throughout testing. A series of mechanical interactions were performed with the ICD leads, including sliding and striking each distal coil against metal and non-metal components of other ICD and pacemaker leads. All direct metal-metal interactions resulted in sensed electrical artefact, including interactions between the bare ICD coil and another bare ICD coil or metal pacemaker ring. Identical mechanical interactions where metal-metal contact was prevented due to an interposed ePTFE covering sleeve were electrically silent with no sensed artefact. CONCLUSIONS: A covering sleeve over the distal high-voltage coil of an integrated bipolar ICD lead can mechanically shield the lead from metal-metal interactions, which might otherwise result in sensed artefact and inappropriate ICD therapies or withholding of pacing output. This finding has implications for lead selection when a new ICD lead is to be implanted adjacent to abandoned intracardiac leads or lead fragments. 相似文献
88.
In a comparative study, we investigated whether or not removed and non-beating hearts could be preserved in vitro by continuous perfusion with oxygen-carrying solutions (blood, perfluoro-carbon emulsion) and simultaneous substitution with specific substrates. We used 18 mongrel dogs subdivided into 2 groups (1st group: perfluorocarbon emulsion; 2nd group: blood); the perfusion time was 9 h. In addition to parameters to control the medium of the perfusion solution, we measured parameters that would allow us to assess the success of the extended perfusion. These parameters were high-energy phosphates and, in particular, electron optical analysis. At the end of the perfusion period, electron optical analysis revealed a mild and reversible ischemic reaction by the myocardial cells in both groups. However, statistical analysis showed (1) a significant increase in the ischemic reaction for both groups over the perfusion period (P=0.02), and (2) a significant, even more pronounced ischemic reaction in the subendocardial myocardium (P=0.025). It should be noted that distinctly interstitial edema developed during the perfusion period and that this would appear to be a fairly critical problem with extended continuous isolated heart perfusion.Supported by grants of the Deutsche Forschungsgemeinschaft 相似文献
89.
Functional expression of the Chlorella hexose transporter in Schizosaccharomyces pombe 总被引:1,自引:0,他引:1 下载免费PDF全文
Sauer N Caspari T Klebl F Tanner W 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(20):7949-7952
Schizosaccharomyces pombe cells were transformed with an S. pombe expression vector containing a full-length cDNA of the Chlorella hexose transporter. The transformed cells accumulated 3-O-methylglucose up to 10-fold, whereas wild-type S. pombe and control transformants could only equilibrate this sugar analogue. In a pH-jump experiment, in which extracellular pH was lowered by 1.9 units, the accumulation ratio was increased in transformed cells but not in control cells. This result indicates that the gene product, Chlorella H+/glucose-symporter protein, and a pH gradient suffice for active sugar uptake. Km values for glucose, 6-deoxyglucose, and 3-O-methylglucose of 1.5 x 10(-5) M, 2.7 x 10(-4) M, and 1.0 x 10(-3) M, respectively, were identical in Chlorella and in S. pombe cells transformed with Chlorella cDNA and approximately 100-fold lower than those of the endogenous transport system of S. pombe. 相似文献
90.
Stephan Sauer Sandra S. Burkett Mark Lewandoski Amar J. S. Klar 《Chromosome research》2013,21(3):311-328
Sister chromatids contain identical DNA sequence but are chiral with respect to both their helical handedness and their replication history. Emerging evidence from various model organisms suggests that certain stem cells segregate sister chromatids nonrandomly to either maintain genome integrity or to bias cellular differentiation in asymmetric cell divisions. Conventional methods for tracing of old vs. newly synthesized DNA strands generally lack resolution for individual chromosomes and employ halogenated thymidine analogs with profound cytotoxic effects on rapidly dividing cells. Here, we present a modified chromosome orientation fluorescence in situ hybridization (CO-FISH) assay, where identification of individual chromosomes and their replication history is achieved in subsequent hybridization steps with chromosome-specific DNA probes and PNA telomere probes. Importantly, we tackle the issue of BrdU cytotoxicity and show that our method is compatible with normal mouse ES cell biology, unlike a recently published related protocol. Results from our CO-FISH assay show that mitotic segregation of mouse chromosome 7 is random in ES cells, which contrasts previously published results from our laboratory and settles a controversy. Our straightforward protocol represents a useful resource for future studies on chromatid segregation patterns of in vitro-cultured cells from distinct model organisms. 相似文献