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排序方式: 共有996条查询结果,搜索用时 15 毫秒
991.
GJ Cooper PS Withington AJ Wood PG Magee CT Lewis TR Graham 《Canadian Metallurgical Quarterly》1995,19(9):950-951
Right ventricular failure may complicate isolated left ventricular assistance. In a series of 8 patients undergoing left ventricular assistance in postcardiotomy cardiogenic shock, right ventricular failure developed in 5, directly contributing to death in all cases despite initially satisfactory support. Difficulty in grafting a dominant right coronary artery was a common factor in all cases. Early consideration should be given to biventricular support under these circumstances. 相似文献
992.
GH Draffan PJ Lewis JL Firmin TW Jordan CT Dollery 《Canadian Metallurgical Quarterly》1976,3(3):489-495
Bacterial luciferase from Photobacterium phosohoreum was found to produce bioluminescence on reaction with FMN and H2O2 in the presence of aldehyde. This luminescence is presumably produced by the same X1 intermediate as that found in FMNH2-O2 initiated luminescence. From the ratio of the light intensities of the FMN-H2O2 initiated reactions, we calculated the association constant of the reaction, luciferase+FMN+H2O2in equilibriumX1, and estimated its temperature dependence. From these results we calculated the thermodynamic parameters of the reaction, luciferase+FMNH2+O2in equilibriumX1. We found that the free energy level of X1 is only 3.2 kcal below that of fr-e FMN and H2O2. We also estimated the thermodynamic parameters of other steps of the luminescent reaction. The values obtained showed that the formation of X1 from luciferase, FMNH2 and O2 involves a positive entropy change, but the intermediate is in a state stabilized against decomposition. Results also suggest a considerable degree of electronic rearrangement on formation of the excited-state molecule from the X1-aldehyde complex. 相似文献
993.
A 55-year-old male presented complaining of pain at his right fourth toe and dorsal fourth web space. Physical examination findings pointed to a lesion affecting the superficial peroneal nerve. A schwannoma of the superficial peroneal nerve was subsequently excised, relieving the patient's symptoms. In the differential diagnosis of nontraumatic and/or nonarthritic toe and foot pain, benign tumors, including schwannomas of the tibial and peroneal nerves, should be considered. 相似文献
994.
CT Chung DD Rabuzzi RH Sagerman GA King RR Gacek 《Canadian Metallurgical Quarterly》1980,106(12):763-766
Twenty-five patients with primary epithelial carcinoma of the nasal cavity without nodal or distant metastases were treated by irradiation between 1967 and 1978. Small field, beam-directed techniques delivered 6,000 to 7,000 rads with conventional fractionation. Control of the primary tumor was achieved in 21 (84%) patients after irradiation. All five treatment failures (one infield only, three infield recurrence with lymph node metastases, and one regional cervical node metastasis) were evident within six months; all five patients died of cancer. The adjusted actuarial survival rate at three years was 76%. Failure in the untreated neck was only 5% when the primary carcinoma was controlled and 16% overall. The literature has been reviewed with attention to tumor control rates and survival. 相似文献
995.
996.
The homeodomain is a DNA binding motif that is usually conserved among diverse taxa. Rapidly evolving homeodomains are thus of interest because their divergence may be associated with speciation. The exact site of the Odysseus (Ods) locus of hybrid male sterility in Drosophila contains such a homeobox gene. In the past half million years, this homeodomain has experienced more amino acid substitutions than it did in the preceding 700 million years; during this period, it has also evolved faster than other parts of the protein or even the introns. Such rapid sequence divergence is driven by positive selection and may contribute to reproductive isolation. 相似文献