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101.
Kemmer N Neff G Secic M Zacharias V Kaiser T Buell J 《Digestive diseases and sciences》2008,53(2):551-555
Liver transplantation (LT) as a treatment for Hepatocellular Carcinoma (HCC) provides excellent outcomes if restricted to
patients who meet the Milan criteria (MC). The aim of this study was to evaluate the influence of ethnicity on eligibility
for LT based on the MC. This is a retrospective cohort study of patients diagnosed with HCC at our institution between January
2000 and September 2005. We identified 169 patients, of whom 135 were male (80%), 108 were Caucasian (64%), 29% were African
American (AA) and 7% were of other ethnicity. Eighty two patients (49%) met the MC at diagnosis. Age, gender, severity of
liver disease or insurance status was not predictive of meeting MC at diagnosis. Ethnicity was the only significant predictor
for failure to meet MC. Significantly fewer Caucasians exceeded the MC compared to AA (44 vs. 71%; P = 0.0015). Conclusion AA are more likely to present with HCC that exceeds the MC. 相似文献
102.
Gene RB cloned from Solanum bulbocastanum confers broad spectrum resistance to potato late blight 总被引:8,自引:0,他引:8
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Song J Bradeen JM Naess SK Raasch JA Wielgus SM Haberlach GT Liu J Kuang H Austin-Phillips S Buell CR Helgeson JP Jiang J 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(16):9128-9133
Late blight, caused by the oomycete pathogen Phytophthora infestans, is the most devastating potato disease in the world. Control of late blight in the United States and other developed countries relies extensively on fungicide application. We previously demonstrated that the wild diploid potato species Solanum bulbocastanum is highly resistant to all known races of P. infestans. Potato germplasm derived from S. bulbocastanum has shown durable and effective resistance in the field. Here we report the cloning of the major resistance gene RB in S. bulbocastanum by using a map-based approach in combination with a long-range (LR)-PCR strategy. A cluster of four resistance genes of the CC-NBS-LRR (coiled coil-nucleotide binding site-Leu-rich repeat) class was found within the genetically mapped RB region. Transgenic plants containing a LR-PCR product of one of these four genes displayed broad spectrum late blight resistance. The cloned RB gene provides a new resource for developing late blight-resistant potato varieties. Our results also demonstrate that LR-PCR is a valuable approach to isolate genes that cannot be maintained in the bacterial artificial chromosome system. 相似文献
103.
104.
C Y Lui J P Ornato J C Buell R L Grissom C C Erickson 《Journal of electrocardiology》1987,20(3):241-246
Using more recent VCG and ECG criteria, the relative accuracy of these two tests in detecting inferior wall MI over time was evaluated in 38 of 236 patients undergoing elective left ventriculographic and coronary angiographic studies who had clinical plus angiographic evidence of inferior wall myocardial infarction. The overall sensitivity and specificity of the ECG criteria of the New York Heart Association and Warner did not differ from that of the VCG criteria of Starr and Takatsu. There was a trend toward decreased sensitivity in both VCG criteria and the ECG criterion of Warner in detecting inferior wall myocardial infarction greater than or equal to 18 months, although the difference did not reach statistical significance. Changing the age of infarction to greater than or equal to 3, greater than or equal to 6, greater than or equal to 12, or greater than or equal to 24 months did not yield a different result. It is concluded that VCG is not superior to ECG in the diagnosis of inferior wall MI regardless of time since occurrence of infarction. 相似文献
105.
W Guenther E Moser F Mueller-Spahn K von Oefele U Buell H Hippius 《Neuropsychopharmacology》1986,21(10):889-899
In this investigation we examined eight Type I (positive symptoms without marked negative symptomatology), eight Type II (marked negative symptoms) schizophrenic patients of the disordered and paranoid diagnostic subgroups (DSM-III 295.1 and 295.3), eight severely (HAMD above 35) and eight less severely (HAMD below 20) endogenous depressed patients, and eight control persons using the 133Xe inhalation method in resting condition and during motor activity of the dominant right hand. In all patient groups we found flow activation patterns that were different from those observed in normal control persons. During motor activation in Type I schizophrenics and in less severely endogenous depressed patients, we found a bilateral hyperflow and a diffuse cortical flow increase, also involving deeper cerebral structures. In Type II schizophrenics and severely endogenous depressed patients, however, we found a widespread nonreactivity of the regional cerebral blood flow (rCBF) to motor activation, with no flow increase in the contralateral primary motor area. In normal control individuals, we reproduced a 25% flow increase that was strictly limited to the contralateral primary motor area, as already reported by other authors. As only the schizophrenic patients were not under antipsychotic medication (4 with a washout of at least 1 week prior to the investigation, 12 never treated with drugs before), contaminating effects of the medication cannot be ruled out for the endogenous depressed patient groups. However, in schizophrenic patients, these results suggest a diffuse disorganization and lack of laterality of motor functional systems. In addition, the change from hyperactivity to hyporeactivity might indicate cerebral functional correlates of the change from Type I to Type II symptomatology in schizophrenic patients, which could possible prove to be of clinical importance. 相似文献
106.
Hand-assisted laparoscopic live-donor nephrectomy 总被引:2,自引:0,他引:2
107.
108.
Fibrosing alveolitis: CT-pathologic correlation 总被引:13,自引:0,他引:13
Computed tomography (CT) was performed within 10 days of open lung biopsy in nine patients with fibrosing alveolitis. One-centimeter collimation contiguous scans through the chest were obtained in all patients. Additional 1.5-mm collimation scans were obtained in the area in which lung biopsy was later performed in six patients. In seven patients, CT demonstrated patchy involvement of the lung parenchyma, areas with a reticular pattern being intermingled with areas of normal lung. The reticular pattern was associated with cystic spaces 2-4 mm in diameter and was more severe in the lung periphery. Histologically, the reticular pattern corresponded to areas of irregular fibrosis. One patient had diffuse honeycombing (2-20-mm cysts), and one had honeycombing only in the lung periphery. In all patients, CT clearly defined the architectural changes seen on open lung biopsy. These changes were much better seen on the 1.5-mm than on the 10-mm collimation scans. CT may be helpful in determining the pattern and distribution of lung involvement in patients with fibrosing alveolitis and in guiding the surgeon to the most appropriate area(s) for biopsy. 相似文献
109.
Susan Kirk MSc BNurs RGN RM RHV DN Cert Caroline Carlisle MSc BA RGN RM DN Cert DipCouns RNT Karen A Luker PhD BNurs RGN RHV DN Cert 《Journal of advanced nursing》1996,24(5):1054-1062
This paper presents findings from a national study conducted over a 3-year period (1991–94) which examined the changing role of the nurse teacher The study used multiple methods to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers) This paper presents the findings relating to the development of the nurse teacher's academic role following the introduction of Project 2000 The issues presented and discussed include specialization within the nurse teacher's role, the nature of this specialization and the development of academic credibility and scholarship The implications of these changes in terms of the development of nursing as an academic subject area and the opportunity to contribute to the establishment of research based practice are explored 相似文献
110.
A. D. Michel K. Lundstrm G. N. Buell A. Surprenant S. Valera P. P. Humphrey 《British journal of pharmacology》1996,118(7):1806-1812
1. We have recently provided evidence that [35S]-adenosine 5'-O-[3-thiotriphosphate] ([35S]-ATP gamma S) can label the human bladder recombinant P2X1 purinoceptor (human P2X1 purinoceptor). In this study we have characterized the binding of [35S]-ATP gamma S to a second P2X purinoceptor subtype, the rat PC12 phaeochromocytoma cell recombinant P2X2 purinoceptor (rat P2X2 purinoceptor), and compared its binding properties with those of both endogenous and recombinant P2X1 purinoceptors. 2. Infection of CHO-K1 cells with the rat P2X2 purinoceptor using Semliki forest virus (SFV) resulted in the expression of high affinity (pKd = 9.3; Bmax = 18.1 pmol mg-1 protein) binding sites for [35S]-ATP gamma S but not for [3H]-alpha, beta-methylene ATP ([3H]-alpha beta meATP). Since functional P2X purinoceptors could be detected electrophysiologically in these cells, but not in non-infected or CHO-K1 cells infected with SFV containing the LacZ gene, these results suggest that the rat P2X2 purinoceptor can be labelled using [35S]-ATP gamma S. 3. The binding characteristics of the rat P2X2 purinoceptor were compared with those of the human P2X1 purinoceptor, which was also expressed in the CHO-K1 cells using SFV. A major difference between the two recombinant P2X purinoceptor types was in the binding characteristics of alpha, beta-methylene ATP (alpha beta meATP). Thus, in the absence of divalent cations, alpha beta meATP possessed low affinity for both the human P2X1 purinoceptor (pIC50 = 7.2) and rat P2X2 purinoceptor (pIC50 = 7.1) labelled using [35S]-ATP gamma S. However, when the recombinant P2X purinoceptors were labelled with [3H]-alpha beta meATP in the presence of 4 mM CaCl2, the affinity of alpha beta meATP for the human P2X1 purinoceptor increased (pIC50 for alpha beta meATP = 8.2), while the affinity of the rat P2X2 purinoceptor for alpha beta meATP did not change (pIC50 for alpha beta meATP = 6.8). 4. Affinity estimates of 15 other nucleotide analogues for the [35S]-ATP gamma S binding sites on the two recombinant P2X purinoceptor subtypes were surprisingly similar (less than 5 fold difference), the only exception being 2'-deoxy ATP which possessed 8 fold higher affinity for rat P2X2 than for human P2X1 purinoceptors. In contrast dextran sulphate and the P2 purinoceptor antagonists, pyridoxalphosphate-6-azophenyl-2', 4'-disulphonic acid and 4,4'-diisothiocyanatostilbene-2,2' disulphonic acid, possessed 7 to 33 fold higher affinity for the human P2X1 than for the rat P2X2 purinoceptor. These data provide a correlation coefficient (r) of 0.894. 5. There was some evidence for species differences in the P2X1 purinoceptor. Thus, most nucleotides possessed slightly greater (up to 9-10 fold), while the P2 purinoceptor antagonists possessed slightly lower (up to 7-16 fold), affinity for the endogenous rat vas deferens and rat bladder P2X1 purinoceptors than for the human recombinant P2X1 purinoceptor. These differences were reflected in a slightly lower correlation coefficient, when comparing across species between the human recombinant P2X1 purinoceptor and the endogenous P2X1 purinoceptors labelled in either the rat deferens (r = 0.915) or the rat bladder (r = 0.932), than when comparing within species between the endogenous rat vas deferens and rat bladder P2X1 purinoceptors (r = 0.995). 6. In summary, [35S]-ATP gamma S can be used to label the recombinant P2X1 and P2X2 purinoceptors. Despite the marked differences reported between these two forms of P2X purinoceptor in functional studies, the differences in binding studies were more limited. However, a number of antagonists could discriminate between the P2X purinoceptor subtypes in the binding studies raising expectations that selective antagonists for these receptors can be developed. 相似文献