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101.
The present experiment examined the effect of different approach motivational body postures on relative left frontal cortical activity, which has been linked with approach motivation. Three body postures were manipulated to create three levels of approach motivation. Consistent with the motivational direction model, results indicated that leaning forward with arms extended (high approach) caused greater left frontal cortical activation as compared to reclining backwards (low approach). This is the first experiment to demonstrate this effect, and it suggests that leaning forward as compared to reclining backward increases approach motivation. These results provide important implications for the motivational direction model and embodiment research. 相似文献
102.
Braet F Nagatsuma K Saito M Soon L Wisse E Matsuura T 《World journal of gastroenterology : WJG》2007,13(6):821-825
Colorectal cancer (CRC) is a common malignant disease and the severe nature of cases in men and women who develop colorectal cancer makes this an important socio-economic health issue. Major challenges such as understanding and modeling colorectal cancer pathways rely on our understanding of simple models such as outlined in this paper. We discuss that the development of novel standardized approaches of multidimensional (correlative) biomolecular microscopy methods facilitates the collection of (sub) cellular tissue information in the early onset of colorectal liver metastasis and that this approach will be crucial in designing new effective strategies for CRC treatment. The application of X-ray micro-computed tomography and its potential in correlative imaging of the liver vasculature will be discussed. 相似文献
103.
Mannose-binding lectin and susceptibility to infection in Chinese patients with systemic lupus erythematosus 总被引:1,自引:0,他引:1
OBJECTIVE: To test the hypothesis that low serum mannose-binding lectin (MBL) levels, as a result of the single-nucleotide polymorphisms in the promoter region (-221 X/Y) and exon 1 (codon 54 A/B) of the MBL2 gene, predispose to infection in Chinese patients with systemic lupus erythematosus (SLE). METHODS: Two hundred forty-five patients with SLE were prospectively followed for the development of major infective episodes that required hospitalization and antibiotic treatment during 1992-2005. MBL genotypes were determined by polymerase chain reaction and serum MBL levels were measured by ELISA. RESULTS: In total, 254 major infections developed in 130 patients. Serum MBL levels were shown to correlate inversely with the number of bacterial infections (r = -0.13, p = 0.03). The distribution of MBL genotypes was similar in patients with and without major infection (p = 0.84). Patients with major infection also had more major lupus exacerbations that required daily prednisolone dose > or = 15 mg. Logistic regression showed that log MBL level (odds ratio 0.516, 95% confidence interval 0.305-0.873; p = 0.01) and major lupus exacerbation (OR 1.382, 95% CI 1.154-1.654; p < 0.001) were independent risk factors to major bacterial infection after adjustment for age and disease duration. Multiple regression analysis showed an increase in risk of bacterial infection by 34.2% for every decrease in serum MBL level by one log, and by 22.8% for each increase in number of major lupus exacerbations. CONCLUSION: Low serum MBL level predisposes Chinese patients with SLE to more major infections, in particular bacterial ones. 相似文献
104.
Vos E 《The Canadian journal of cardiology》2007,23(5):397-8; author reply 398
105.
106.
Eiken O Kölegärd R Bergsten E Grönkvist M 《Aviation, space, and environmental medicine》2007,78(4):392-398
INTRODUCTION: G protection in the 39 Gripen aircraft is provided by a full coverage anti-G suit, a pressure-breathing system, and anti-G straining maneuvers (AGSM). The purpose was to study (1) the interaction of pressure breathing and AGSM while wearing an anti-G suit; and (2) the G-protective properties of the anti-G suit alone and in combination with the pressure-breathing system. METHODS: During rapid onset rate G-time profiles (< or =9 G), 10 subjects were investigated in 5 conditions: (I) sitting relaxed, without any G-protective garment; (II) sitting relaxed and wearing an anti-G suit; (III) sitting relaxed, wearing an anti-G suit, and pressure breathing; IV) wearing an anti-G suit and performing AGSM; and V) wearing an anti-G suit, pressure breathing, and performing AGSM. In supplementary experiments (n=9), the share of the anti-G suit protection afforded by the abdominal bladder was investigated. RESULTS: G tolerance was 3.4 Gz (range: 2.8-4.3) in condition I, > or = 6.5 Gz (4.5-9.0) in II, > or = 8.0 Gz (6.5-9.0) in III, > or = 8.9 Gz (8.5-9.0) in IV and > or = 9.0 Gz (8.5-9.0) in V. In the supplementary experiments, the anti-G suit afforded a 2.8-G protection, a third of which was contributed by the abdominal bladder. In the relaxed state, pressure applied to the airways was transmitted undistorted to the intrathoracic space. During AGSM, intrathoracic pressure rose to 10-14 kPa, regardless of whether AGSM was performed with or without pressure breathing. DISCUSSION: AND CONCLUSIONS: The anti-G suit and the pressure breathing system provide G protection of > or = 4.6 G, of which the anti-G suit contributes about 3.0 G. The C-protective properties of the anti-G suit and those of pressure breathing appears to be additive, whereas the G protection afforded by pressure breathing does not add to that provided by AGSM. 相似文献
107.
High-resolution computed tomography accurately predicts resectability in hilar cholangiocarcinoma 总被引:3,自引:0,他引:3
Aloia TA Charnsangavej C Faria S Ribero D Abdalla EK Vauthey JN Curley SA 《American journal of surgery》2007,193(6):702-706
INTRODUCTION: Despite the use of radiologic, endoscopic, and laparoscopic staging techniques, the rate of nontherapeutic laparotomies in patients with hilar cholangiocarcinoma remains high. This study evaluated the accuracy of preoperative high-resolution computed tomography (HRCT) to determine resectability in this setting. PATIENTS AND METHODS: Preoperative helical HRCT (2 contrast phases, rapid intravenous contrast bolus, 2.5-mm section thickness) for 32 consecutive patients who underwent laparotomy for the diagnosis of hilar cholangiocarcinoma from 2000 to 2005 were reviewed by a hepatobiliary radiologist. The accuracy of HRCT was determined by comparison of the imaging interpretation to intraoperative and pathologic findings. The chi-square test was used to identify imaging findings that best predicted unresectability. RESULTS: Fourteen of the 32 (44%) study patients were unresectable (extension along bile duct, 4; peritoneal metastases, 4; vascular encasement, 3; noncontiguous liver metastases, 2; N2 lymphadenopathy, 1). HRCT correctly predicted resectability in 17 of 18 patients who underwent therapeutic laparotomy (sensitivity = 94%). HRCT correctly predicted the inability to resect in 11 of the remaining 14 cases (specificity = 79%). In the 3 cases in which HRCT predicted resectability and the patient was unresectable, subcentimeter peritoneal disease, a subcentimeter liver metastasis, and distal bile duct involvement were responsible factors. The negative and positive predictive values of HRCT were 92% and 85%, respectively. Individual radiographic findings that best predicted unresectability were peritoneal spread (P = .015) and hepatic artery (P = .006) or portal vein (P = .002) involvement. CONCLUSIONS: Preoperative HRCT accurately predicts resectability in patients with hilar cholangiocarcinoma. Identification of specific radiographic features, in particular major vascular involvement and peritoneal abnormalities, is now used by our group to avoid unnecessary laparotomy. 相似文献
108.
109.
Introduction: To evaluate the incidence and impact of early post‐chemoradiation (cRT) ‘pseudoprogression’ (PsPD) amongst glioblastoma multiforme (GBM) patients treated with the current standard of care – 60 Gy conformal radiotherapy with concurrent low‐dose temozolomide, followed by six cycles of high‐dose temozolomide (the ‘Stupp protocol’). Methods: Clinical notes and radiology reports for GBM patients treated as per the Stupp protocol were reviewed. PsPD was defined as apparent radiological progression on the first post‐cRT scan, with further imaging within 3 months being stable or improving, while true early progression (ePD) was confirmed by continued progression in the subsequent 3 months following the first post‐cRT scan. Results: Of the 68 patients evaluated, 14 (21%) and 27 (40%) experienced PsPD and ePD, respectively; 3/14 (21%) patients experiencing PsPD and 14/27(52%), ePD were symptomatic for progression on first post‐cRT follow‐up (P = 0.096 for difference). Median survival for patients with ePD, PsPD and neither were 10.4, 27.4 and 13.0 months, respectively (P = 0.003 for ePD vs. PsPD, P = 0.19 for neither vs. PsPD groups). Conclusion: These data confirm a significant incidence of PsPD in post‐cRT GBM patients, associated with improved median survival compared with those with neither ePD nor PsPD (not statistically significant). It appears likely that PsPD actually represents tumour response, conflicting with the traditional notion that increase in lesion size on contrast‐enhanced imaging represents disease progression. Early post‐cRT imaging should thus be interpreted with caution. Accompanying clinical symptoms are more commonly associated with ePD, but do not reliably distinguish PsPD from ePD. 相似文献
110.
The hedgehog (Hh) pathway has been shown to be activated in numerous malignancies as well as in cancer stem cells. We sought to determine the importance of the Hh pathway in regulating growth and development of ovarian cancer spheroid-forming cells (SFCs). Ovarian cancer cell lines (ES2, TOV112D, OV90, and SKOV3) as well as a normal ovarian epithelial cell line (IOSE80) were grown in non-adherent growth conditions to form SFCs. Western blot analysis was used to determine the expression of Hh pathway proteins SMOH, PTCH, GLI1. SFCs were treated with Hh agonists (SHH and IHH) as well as an Hh inhibitor (cyclopamine) to determine changes in spheroid growth and survival. All ovarian cancer cell lines readily formed spheroids in non-adherent growth conditions while IOSE80 failed to form SFCs. Compared to IOSE80, ovarian cancer cell lines demonstrated significant activation of the Hh pathway as defined by increased expression of intranuclear GLI1. Both Hh agonists demonstrated significant increases in spheroid volume of at least 42-fold for SHH-treated cells and 46-fold for IHH-treated cells. With regard to survival, SFCs were 30-50% more resistant to cyclopamine than their corresponding monolayer cells. Despite this resistance, inhibition of the Hh pathway with cyclopamine prevented further growth of SFCs with a 10-, 5-, and 4-fold restriction in growth for ES2, SKOV3, and TOV112D, respectively. The hedgehog pathway appears to be important in regulating growth of ovarian cancer spheroid-forming cells. The activation and inhibition of this pathway demonstrates significant correlation to enhanced growth and growth restriction, respectively. 相似文献