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排序方式: 共有1033条查询结果,搜索用时 15 毫秒
1.
Marlen Z. Gonzalez Lane Beckes Joanna Chango Joseph P. Allen James A. Coan 《Social cognitive and affective neuroscience》2015,10(7):921-928
Neuroimaging studies using the social-exclusion paradigm Cyberball indicate increased dorsal anterior cingulate cortex (dACC) and right insula activity as a function of exclusion. However, comparatively less work has been done on how social status factors may moderate this finding. This study used the Cyberball paradigm with 85 (45 females) socio-economically diverse participants from a larger longitudinal sample. We tested whether neighborhood quality during adolescence would predict subsequent neural responding to social exclusion in young adulthood. Given previous behavioral studies indicating greater social vigilance and negative evaluation as a function of lower status, we expected that lower adolescent neighborhood quality would predict greater dACC activity during exclusion at young adulthood. Our findings indicate that young adults who lived in low-quality neighborhoods in adolescence showed greater dACC activity to social exclusion than those who lived in higher quality neighborhoods. Lower neighborhood quality also predicted greater prefrontal activation in the superior frontal gyrus, dorsal medial prefrontal cortex and the middle frontal gyrus, possibly indicating greater regulatory effort. Finally, this effect was not driven by subsequent ratings of distress during exclusion. In sum, adolescent neighborhood quality appears to potentiate neural responses to social exclusion in young adulthood, effects that are independent of felt distress. 相似文献
2.
腹腔镜辅助下大隐静脉隔绝术治疗大隐静脉曲张60例 总被引:1,自引:0,他引:1
目的探讨腹腔镜辅助下大隐静脉隔绝术的疗效。方法2000年1月~2004年1月对60例66条大隐静脉曲张腹腔镜辅助下行大隐静脉隔绝术,腹腔镜辅助下高位结扎、电灼大腿段大隐静脉,阻断其小腿段所有属支及交通支,使大隐静脉与体循环隔绝。结果手术时间30~60min,(50±9)min;术后住院时间3~5d,(3.5±0.6)d。60例随访1~36个月,平均28个月,无复发。结论腹腔镜辅助下大隐静脉隔绝术创伤小,疗效好,复发率低,是治疗大隐静脉曲张的理想术式。 相似文献
3.
胸主动脉夹层动脉瘤腔内隔绝术手术入路的探讨 总被引:3,自引:0,他引:3
目的 探讨为胸主动脉夹层动脉瘤(TAD)行腔内隔绝术(EVE)选择合适的导入动脉。方法 以彩超,CTA或MRA为检查手段,评估导入动脉(股动脉、髂总动脉、腹主动脉下段等)的直径大小(≥8mm)、有否硬化斑块、狭窄、是否被夹层累及、有否扭曲及其程度,从而选择具体的手术入路。结果 本组37例TAD行EVE术所选择经股动脉手术入路23例、经髂总动脉手术入路14例。未选择经腹主动脉下段手术入路。即时操作成功率为100%。结论 合理的选择导入动脉作为手术入路,是EVE手术治疗TAD顺利完成的要点。 相似文献
4.
T. Takaki 《Medical & biological engineering & computing》1988,26(4):397-403
The paper considers the limiting factors in EEG enhancement in the presence of electrosurgery interference and presents a
design for a useful fibre-optic EEG monitoring instrument which is free from such problems as electrical shock (micro and
macroshock), patient burns and susceptibility to electrosurgery interference associated with conventional EEG monitors. 相似文献
5.
Exclusion mapping of 12 X-linked disease loci and 10 DNA probes from the long arm of the X-chromosome 总被引:3,自引:0,他引:3
Specific chromosome rearrangements associated with disease entities are invaluable resources for physical mapping. A deletion on the X chromosome of a male leads to the nullisomy for X-linked genes, resulting in the onset of genetic diseases and/or the absence of the DNA probe detectable sequences. This permits the localization of these loci within the deleted area. On the other hand, the region for some other X-linked loci can be excluded from the deleted area according to the absence of the characteristic symptoms of the disease and/or the presence of the hybridization signals. An interstitial deletion on the long arm of the X chromosome of a male has been characterized by high resolution banding. The karyotype of the proband is 46,Y,del(X)(pter----q21.1::q21.33----qter). The regions for 12 X-linked disease loci as well as 10 DNA probes are excluded from the deleted area, and localized either proximally or distally to the deletion. The results also reveal a controversy in the present linkage data concerning the assignment of these loci. 相似文献
6.
Optimum support properties for protein separations by high-performance size exclusion chromatography
Optimum chromatographic properties of high performance size exclusion chromatography (HPSEC) of proteins, such as resolution, molecular weight accuracy and recovery, are obtained on packings and columns with tailor-made physical and chemical structures, employed at properly adjusted eluent compositions and operation conditions. SEC-theory suggests that a broad molecular weight fractionation range and high linearity of the log-linear calibration plot can be achieved by the use of two packings (10- and 80-nm pore size, characterized by a pore-size distribution (psd) equal to or less than 1 decade and by equal internal column porosity (p)), rather than a single 30- to 50-nm pore-size packing with a wide psd. Favourably high-phase ratios of (p)/(o)/ 1.0 for HPSEC columns were accomplished with a minimum interstitial column porosity (o) and a high value for the internal column porosity (p) (the specific pore volume, nu(p), multiplied by the packing density, varrho(p).) Ligands such as diol, N-acetoxyamino and oligomeric ether with a propyl- or propoxy-spacer bonded to the silica at the highest density appear to provide high mass recovery and bioactivity as well as chemical stability. Such packings, available in 3-5 mum particle size ranges of narrow distribution, packed into columns 6 mm i.d. and 500 mm in length, offer the best compromise with respect to resolution, speed and pressure drop. More careful studies are required to explain the effects of protein conformational changes and interconversions during elution on HPSEC columns. 相似文献
7.
Saqib Masroor Qiong Qiu Mohamad Alghothani Rajesh Gupta George V. Moukarbel 《Journal of cardiac surgery》2021,36(1):398-400
Percutaneous occlusion of the left atrial appendage is increasingly being used as an alternative for stroke prevention in patients with non‐valvular atrial fibrillation at high risk of complications from long term anticoagulation. We describe a case of left atrial appendage perforation during Watchman device implantation requiring emergency repair of the left atrium using sternotomy and cardiopulmonary bypass. Technical considerations for surgical decision making are discussed; in hemodynamically unstable patients as well as those at high risk for embolization. 相似文献
8.
Secondary hyperparathyroidism and osteopenia in women following gastric exclusion surgery for obesity 总被引:3,自引:0,他引:3
J. L. Shaker MD A. J. Norton M. F. Woods M. D. Fallon J. W. Findling 《Osteoporosis international》1991,1(3):177-181
Gastric exclusion has been introduced as a surgical treatment for morbid obesity. We describe two women who had undergone gastric bypass for obesity with metabolic bone disease and secondaryhyperparathyroidism. In one patient transiliac bone biopsy after double tetracycline labelling demonstrated histologic evidence of hyperparathyroidism with osteitis fibrosa cystica. Six additional women who had undergone gastric exclusion were evaluated. Serum phosphorus, calcium, and creatinine were normal in all but one patient who had hypocalcemia. Serum immunoreactive parathyroid hormone was elevated in seven of eight patients and urinary calcium was 2 mmol/d (80 mg/24 h) in 6 patients. Lumbar spine bone mineral density was 86±7 (mean±SE) per cent of predicted and femoral neck bone mineral density was 89±6 per cent of predicted. Women who have had gastric exclusion for obesity may develop secondary hyperparathyroidism which could result in loss of bone mass.Deceased 相似文献
9.
鼻腔神经部分切断术及下鼻甲粘骨膜下剥离术治疗变应性鼻炎18例临床分析 总被引:4,自引:2,他引:4
目的:观察鼻腔神经部分切断术和下鼻甲粘骨膜下血管神经离断术对变应性鼻炎的疗效。方法:对18例常年性变应性鼻炎患者进行鼻腔神经部分切断术与下鼻甲粘骨膜下血管神经离断术。所有病例随访12个月,评价其临床效果。结果:10例临床症状消失,体征明显改善;7例临床症状明显缓解,体征改善;1例无效。总有效率94.4%。结论:鼻腔神经部分切断和下鼻甲粘骨膜下血管神经离断术治疗常年性变应性鼻炎效果显著。 相似文献
10.
Nakamura H Yuasa I Umetsu K Henke J Henke L Nanba E Kimura K 《International journal of legal medicine》2000,114(1-2):114-117
In a German paternity test, an alleged father was excluded only by reverse homozygosity of ORM1 phenotypes (mother ORM1 S, child ORM1 S and alleged father ORM1 F1) out of the 28 classical and DNA markers investigated. Without the ORM1 system the biostatistical probability of paternity was calculated to exceed 99.9999%. The intensity of the immunoprinted bands of the ORM1 protein for the child and alleged father after isoelectric focusing appeared to be reduced to about half. To identify a possible null allele, gene-specific amplification followed by single-strand conformation polymorphism and sequencing analyses were carried out. Deletion of one of the two copies of a 4 bp direct repeat sequence (GTCT) in exon 4 of the consensus sequence of ORM1*F1 was observed in the child and alleged father. Thus, the sharing of a rare mutant gene, ORM1*Q0köln, increased the probability of paternity. 相似文献