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排序方式: 共有532条查询结果,搜索用时 31 毫秒
1.
Sajja Lokeswara Rao Mannam Gopichand Sompali Sriramulu Reddy Karri Venkata Ravirala Bala Raju Raju Bhupathiraju Soma Raju Penmetcha Krishnam 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(4):173-177
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass
has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried
out to compare mortality and morbidity in the off-pump and on-pump CABG groups.
Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG
and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for
bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL)
pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared.
Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG
with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12%
although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure
between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001).
Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in
both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in
off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and
hospital stay in OPCAB group. 相似文献
2.
Laccase from the white-rot fungus Trametes versicolor: cDNA cloning of lcc1 and expression in Pichia pastoris 总被引:2,自引:0,他引:2
A cDNA coding for laccase was isolated from the ligninolytic fungus Trametes versicolor by RNA-PCR. The cDNA corresponds to the gene lcc1, which encodes a laccase isoenzyme of 498 amino-acid residues preceded by a 22-residue signal peptide. The lcc1 cDNA was cloned into the vector pHIL-D2 for expression in Pichia pastoris under the control of the AOX1 promoter. Transformants were found to secrete active recombinant enzyme after induction with methanol. The use of growth
medium buffered to pH 6.0 and control of pH during cultivation were found to be important, or even necessary, for obtaining
activity in liquid cultures. The effect of exchanging the native secretion signal for the Saccharomyces cerevisiae α-factor pre-pro secretion signal was studied by cloning the portion encoding the mature enzyme into the vector pPIC9. The
activity obtained for the construct encoding the native laccase signal sequence was found to be seven-fold higher than for
the construct encoding the α-factor secretion signal. Utilisation of the P. pastoris pep4 mutant strain SMD1168 was found to provide a two-fold higher level of activity compared with P. pastoris GS115.
Received: 16 May / 8 August 1997 相似文献
3.
Joanna S. Kruszewska Markku Saloheimo Merja Penttilä Grażyna Palamarczyk 《Current genetics》1998,33(6):445-450
A cDNA coding for GTP: α-d-mannose-1-phosphate guanyltransferase (MPG1 transferase) (EC 2.7.7.13) was isolated from a cDNA library of the Trichoderma reesei RutC-30 strain by suppression of the yeast Saccharomyces cerevisiae mutation in the DPM1gene encoding mannosylphosphodolichol (MPD) synthase. The nucleotide sequence of the 1.6 kb-long cDNA revealed an ORF which
encodes a protein of 364 amino acids. Sequence comparisons demonstrate 70% identity with the S. cerevisiae guanyl transferase gene (MPG1) and 75% identity with the Schizosaccharomyces pombe homologue. No similarity was found with the MPD synthase encoded by the S. cerevisiae DPM1 gene. The possibility that cloned cDNA encodes a product with a MPD synthase activity was also excluded by transforming a
heterozygous S. cerevisiae dpm1::LEU2/DPM1 diploid, which did not lead to the restoration of viability of the dpm1 spores. Simultaneously, a significant increase in MPG transferase activity, as compared with the wild-type yeast, was observed
in cellular extracts when the mpg1 cDNA from Trichoderma was expressed in the S. cerevisiae dpm1-6 mutant.
Received: 21 July 1997 / 24 April 1998 相似文献
4.
5.
Myocardial metabolism and hemodynamics during coronary surgery without cardiopulmonary bypass 总被引:2,自引:0,他引:2
Penttilä HJ Lepojärvi MV Kaukoranta PK Kiviluoma KT Ylitalo KV Peuhkurinen KJ 《The Annals of thoracic surgery》1999,67(3):683-688
BACKGROUND: Although renewed interest has recently been shown in coronary artery bypass grafting without cardiopulmonary bypass, no reports are available on myocardial metabolism and hemodynamics during temporary coronary occlusion and rotation of the contracting heart. METHODS: Changes in myocardial energy metabolism and hemodynamics were monitored in 12 patients undergoing elective coronary artery bypass grafting without cardiopulmonary bypass, and the postoperative efflux of creatine kinase-MB mass and troponin T were also determined. RESULTS: There was a significant increase in myocardial production of ATP degradation products (p = 0.026) and lactate (p = 0.004) during the operation. Myocardial oxygen extraction decreased (p = 0.012) in correlation with use of the short-acting beta-blocker, esmolol (r = -0.71). Apart from a decrease in mean arterial blood pressure (p = 0.002), there were no significant hemodynamic changes during the operation. The overall postoperative troponin T and creatine kinase-MB mass changes remained nonsignificant during the first two postoperative days. One patient had a myocardial infarction, diagnosed by electrocardiography, on the second postoperative day, but otherwise there were no major complications. CONCLUSIONS: Coronary artery bypass grafting without cardiopulmonary bypass seems to be well tolerated as only minor changes in myocardial energy metabolism and hemodynamics are observed during the operation. 相似文献
6.
Weman SM Salminen US Penttilä A Männikkö A Karhunen PJ 《International journal of legal medicine》1999,112(2):107-114
The advantages and limitations of a novel post-mortem angiographic method using solidifying silicone rubber and lead oxide
as a contrast medium in detecting coronary artery graft complications on a routine basis were evaluated in a series of 223
consecutive patients with fatal outcome within 30 days following coronary artery bypass grafting (CABG). Of these patients,
166 (74.4%) were male and 57 (25.6%) female (mean age 61.9 ± 9). Coronary grafts totalled 660 (3.0 per patient) with 517 aortic
and 838 coronary anastomoses. At autopsy, the rubber cast model of the grafts and coronary arterial tree was exposed by a
bend scalpel and sites of possible complications were examined. Post-mortem angiographs were re-evaluated and compared with
preoperative angiographs and dissection findings. By combining the findings of angiography and heart dissection, 122 (54.7%)
of the 223 patients were found to have some type of complication of the graft or the anastomosis. The diagnostic sensitivity
and specificity of postmortem angiography was 100% in assessing narrowing or twisting of the graft as well as narrowing of
the aortal anastomosis, whereas these findings were revealed with difficulty by autopsy dissection only. In cases with correct
x-ray projection, narrowing and occlusion of the proximal aortal and distal coronary anastomosis were also reliably revealed
by angiography. In contrast, graft thrombosis was clearly overdiagnosed by angiography, leading to a lower specificity (84%)
but high sensitivity (100%) in detecting this complication. Post-mortem angiography also failed to detect dissection of the
wall of the graft or anastomosis. Technical problems with this angiographic method were due to too low perfusion pressure,
too rapid polymerizing of the silicone rubber, leakage of contrast medium into the ventricles, or faulty x-ray projections.
These results suggest that our post-mortem angiographic technique, yielding a permanent rubber- cast model of the graft and
anastomosis site, improves the accuracy of diagnostics of postoperative CABG complications and eases postoperative autopsy
dissection, which can now be directed to confirm suspected complications.
Received: 27 October 1997 / Received in revised form: 2 July 1998 相似文献
7.
The histological diagnosis of amniotic fluid embolism (AFE) is based on finding amniotic fluid components in the pulmonary microvasculature. In addition to the distinctive constituents of AFE, placental and decidual tissue fragments as well as isolated trophoblastic cells and megakaryocytes are potentially detectable within pulmonary vessels. The identification of single syncytiotrophoblastic cells (STC), and their differentiation from circulating megakaryocytes (MK) within the lumen of small and medium-sized pulmonary vessels is difficult by classical morphological methods. In a fatal case of AFE, we have successfully detected the simultaneous presence of STC and MK in the pulmonary microvasculature by means of a panel of specific monoclonal (CD61-GpIIIa, -hCG) and polyclonal (FVIII-vW hPL) antibodies. The immunohistochemical analysis for identification of STC and MK should provide more precise data on their incidence and distribution in physiological and pathological conditions as well providing new insights into their physiopathological implications and their correlation with AFE and other gynaecological complications. 相似文献
8.
9.
Li X Tjwa M Van Hove I Enholm B Neven E Paavonen K Jeltsch M Juan TD Sievers RE Chorianopoulos E Wada H Vanwildemeersch M Noel A Foidart JM Springer ML von Degenfeld G Dewerchin M Blau HM Alitalo K Eriksson U Carmeliet P Moons L 《Arteriosclerosis, thrombosis, and vascular biology》2008,28(9):1614-1620
10.
The GPIIIa (beta3 integrin) PlA polymorphism in the early development of coronary atherosclerosis 总被引:2,自引:0,他引:2
Mikkelsson J Perola M Penttilä A Goldschmidt-Clermont PJ Karhunen PJ 《Atherosclerosis》2001,154(3):721-727
The GPIIIa (beta3 integrin) is an integral part of two glycoprotein receptors - the GP(IIb/IIIa) fibrinogen receptors in platelets and the GP(V/IIIa) vitronectin receptors in endothelium and vascular smooth muscle cells (vSMC). The PlA polymorphism of the gene for GPIIIa (beta3 integrin) has been suggested to play an important role in the progression of coronary artery disease (CAD) and in coronary thrombosis. Whether the action of the PlA polymorphism is due to differences in platelet aggregability or function of the vSMC and endothelial GPIIIa is not known. The association of the PlA polymorphism with the early, non-complicated atherosclerosis and CAD was studied in the Helsinki Sudden Death Study (HSDS) comprising two independent, autopsy series of altogether 700 middle-aged Caucasian Finnish men (33-70 year) suffering sudden out-of-hospital death. The burden of complicated lesions was greater in men with the A2 allele (heterozygotes or homozygotes for A2) (P=0.01) compared with PlA1/A1 homozygotes in the entire series. To further estimate the role of platelet-independent GPIIIa receptors, we excluded all cases with coronary thrombosis and thrombus-overlaid complicated lesions. In this subset of men, fibrous coronary lesions were more frequent (OR 2.9; P<0.01) in the coronary arteries of PlA1/A1 homozygotes compared with men with the PlA2 allele. Moreover, men with the PlA1/A1 genotype also had more stenotic coronary arteries (P<0.05) compared with men with the A2 allele at this early, non-complicated stage of atherosclerosis. The findings of this study suggest that Pl(A1/A1) homozygotes may be prone to early atherosclerosis and more rapid progression of stable CAD whereas carriers of the PlA2 allele are more prone to thrombotic complications. We hypothesize that the PlA polymorphism may account for the early atherosclerosis by affecting the function of endothelial and vSMC GP(V/IIIa) receptors, whereas the PlA polymorphism on platelet GP(IIb/IIIa) receptors may play a major role in coronary thrombosis. 相似文献