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21.
小井眼技术的发展与评价 总被引:1,自引:0,他引:1
本文报道了用氯化铁水合物催化肉桂酸和异戊醇的酯化作用,探讨了氯化铁催化合成肉桂酸异戊酯的条件。 相似文献
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LS Wafelman BH Pollock J Kreutzer DS Richards AA Hutchison 《Canadian Metallurgical Quarterly》1999,75(2):73-81
Prognostic factors for survival of 62 fetuses and neonates with nonimmune hydrops fetalis (NIHF) were studied retrospectively. Twenty-eight infants survived >/=28 days which is 45% for all fetuses and newborns diagnosed with NIHF and 61% for liveborns with unresolved NIHF. Univariate analysis identified that mortality was associated with the presence of >/=2 serous cavity effusions and a need for chest compressions at birth. Multivariate logistic regression analysis confirmed that the presence of >/=2 serous cavity effusions was significantly associated with mortality from NIHF <28 days after birth [OR = 48.2 (CI 3.6, 662.9) (p < 0.004)]. We conclude that, compared to published cases from the 1970s and early 1980s, survival of liveborns with NIHF seems improved. The decrease in stillbirths is more notable. The severity of hydrops at birth is the key determinant for survival. 相似文献
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JM Rogers M Usui BH KenKnight RE Ideker WM Smith 《Canadian Metallurgical Quarterly》1997,25(5):749-760
We have developed a method for quantifying the complexity of activation patterns observed during ventricular fibrillation (VF) that is based on our previously reported methodology for decomposing epicardial mapping data into a set of isolated wavefronts. One-half second datasets are acquired from a 21 x 24 array of unipolar electrodes (1 mm spacing), and the wavefronts are isolated. A correlation technique is used to compute the similarity between all possible pairs of the isolated wavefronts. From these data, the wavefronts are sorted into clusters, each of which represents a recurring wavefront morphology. We define multiplicity (M) as the number of clusters needed to account for 90% of the total activations in the VF episode. M measures the complexity of the rhythm. In repetitive patterns (e.g., sinus rhythm), M = 1, indicating that the same morphology repeatedly activates the mapped region. Typically, in VF, M > 1, with larger numbers representing more complex, disorganized patterns. As an example, we computed M at 5, 10, 15, and 20 sec after electrical induction of VF in six pigs. M decreased significantly (p < 0.001), suggesting increasing organization during this period. 相似文献
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BH Güven? T Salman B Tokar E Sürmen T AltuG A Celik 《Canadian Metallurgical Quarterly》1997,12(5-6):367-369
Fetal tissue transplantation has gathered considerable interest among researchers dealing with organ transplantation. A large number of studies concerning fetal intestinal transplantation have been published in the past 2 decades, almost all of them aiming to determine the feasibility of a properly functioning fetal transplant in continuity with the host's own enteral system. This study was designed to determine the absorptive capacity of the neogut in vivo, without anastomosing the transplant to the host's intestine, and to evaluate its use as an accessory enteral segment. Intestinal segments taken from Wistar albino fetuses were transplanted subcutaneously into the abdominal wall of 20 Sprague-Dawley rats. Immunosuppression was maintained by daily cyclosporin A (Cy A) 10 mg/kg injections s.c. and evaluated by determination of serum Cy A level and T-helper/T-suppressor cell ratio. The neogut was converted into a Thiry-Vella loop 2 weeks after transplantation. A test solution composed of 20% glucose and Trophamine was perfused via the stomas; glucose and amino acid absorption gradients were calculated. The gamma-glutamyl transferase (GGT) activity and mitotic index of the neogut were determined. Results were compared to those obtained from the host. There was no significant difference (P > 0.05) in glucose absorption between the neogut and the host tissue. Amino acid absorption and specific GGT activity were significantly less (P < 0.01) in the neogut. There was no significant difference (P > 0.05) between neogut and host intestine in mitotic index. Our data support the idea of using a transplanted fetal intestinal segment as an accessory feeding route. 相似文献
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MR Betts J Krowka C Santamaria K Balsamo F Gao G Mulundu C Luo N N'Gandu H Sheppard BH Hahn S Allen JA Frelinger 《Canadian Metallurgical Quarterly》1997,71(11):8908-8911
We have examined cross-clade HIV-specific cytotoxic T-lymphocyte (CTL) activity in peripheral blood of eight Zambian individuals infected with non-B-clade human immunodeficiency virus type 1 (HIV-1). Heteroduplex mobility assay and partial sequence analysis of env and gag genes strongly suggests that all the HIV-infected subjects were infected with clade C HIV-1. Six of eight C-clade HIV-infected individuals elicited CTL activity specific for recombinant vaccinia virus-infected autologous targets expressing HIV gag-pol-env derived from B-clade HIV-1 (IIIB). Recognition of individual recombinant HIV-1 B-clade vaccinia virus-infected targets expressing gag, pol, or env was variable among the patients tested, indicating that cross-clade CTL activity is not limited to a single HIV protein. These data demonstrate that HIV clade C-infected individuals can mount vigorous HIV clade B-reactive CTL responses. 相似文献
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C Beisland S Kolltveit BH Nilsen NH Hagness 《Canadian Metallurgical Quarterly》1998,118(12):1860-1862
Tetanus has become an uncommon disease in developed countries. Tetanus is caused by exotoxins from the bacteria Clostridium tetani. This microbe, which is obligate anaerobe, is present in soil, and animal and human faeces. The condition usually appears after contamination of wounds. However, reports have been published of tetanus occurring after both acute and selective gastrointestinal surgery. We present a case of severe postoperative tetanus in a 57 year-old woman who underwent bowel resection after strangulation of the ileum. The patient was treated on an intensive care unit and was artificially ventilated for 64 days. Seven months later she had fully recovered. Clinical presentation, diagnosis, treatment, and complications are discussed in the report. The diagnosis of tetanus is made by clinical observation. Nowadays, lack of suspicion of this condition may cause delay in administering proper treatment. Women and older men are often inadequately immunized. Doctors should therefore examine the immunization status of these groups of patients regularly. 相似文献