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Many complex behaviors that do not require learning are displayed and are termed innate. Although traditionally the subject matter of ethology,innate behaviors offer a unique entry point for neuroscientists to dissect the physiological mechanisms governing complex behaviors. Since the last century,converging evidence has implicated the hypothalamus as the central brain area that controls innate behaviors. Recent studies using cutting-edge tools have revealed that genetically-defined populations of neurons residing in distinct hypothalamic nuclei and their associated neural pathways regulate the initiation and maintenance of diverse behaviors including feeding,sleep,aggression,and parental care. Here,we review the newly-defi ned hypothalamic pathways that regulate each innate behavior. In addition,emerging general principles of the neural control of complex behaviors are discussed. 相似文献
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We investigated the effect of guided bony regeneration using collagen membranes for sinus augmentation in the first maxillary molars of 18 adult female beagle dogs. The teeth were extracted bilaterally and the sinus floors were lifted with simultaneous implantation. The grafted material composed of a combination of autografts and Bio-oss in a 2:1 ratio. On the experimental side in each dog, collagen membrane was folded at the lateral osteotomy window, at the apex of the implants, and at a certain part of the palatal bone. On the opposite (control) side, the collagen membrane covered the osteotomy window. Six animals were killed at each of 4, 12, and 24 weeks postoperatively. Gross observation, biomechanical testing, and histological examinations were made. On the experimental side, grafted materials showed no obvious resorption or subsidence, and a new bone had formed at the apex of the implants. On the control side, the grafted materials had been shifted and absorbed. Histological examination showed increased formation of a new bone in the experimental group, which matured over time. At 4 weeks, inflammatory cells were present in the control group, which showed less maturation of the new bone. The pull-out force increased with time and, at week 24, there was a significant difference in pull-out force between the two groups (p<0.01). Guided bony regeneration with the enfolded coverage of membrane can effectively reduce resorption of grafted bone on the apical surface of implants and stimulate formation of the new bone in sinus augmentation. 相似文献
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目的 探讨全容积表观扩散系数(ADC)直方图参数在预测乳腺癌新辅助化疗(NAC)后获得病理完全缓解(PCR)的价值。方法 回顾性分析2016年1月至2017年12月南京医科大学第一附属医院经穿刺病理证实为浸润性乳腺癌的117例患者,在进行NAC前均行常规3.0 T乳腺MRI检查,化疗后手术病理采用Miller-Payne分级系统评价化疗反应,分为病理完全缓解组(PCR)和非病理完全缓解组(nPCR)。人表皮生长因子受体2(HER2)过表达型21例(PCR者5例),三阴性型26例(PCR者6例)。采用Firevoxel软件生成ADC直方图,记录多个ADC直方图参数,包括ADC最小值(ADCmin)、ADC平均值(ADCmean)、ADC最大值(ADCmax)、偏度系数、峰度系数,利用SPSS 24.0计算出ADC第10百分位数(ADC10%)、ADC第50百分位数(ADC50%)、ADC第90百分位数(ADC90%)。采用两独立样本t检验(正态分布)或Mann-Whitney U检验(偏态分布)比较PCR组和nPCR组各ADC直方图参数的差异。采用受试者操作特征(ROC)曲线评价有统计学意义的ADC参数的诊断效能。结果 HER2过表达型在PCR组与nPCR组患者间,峰度系数的差异有统计学意义(P=0.039),ROC曲线下面积为0.813,截断点为1.861,其灵敏度为100.0%,特异度为68.7%。PCR组和nPCR组三阴性型患者间,ADCmean及ADC50%的差异有统计学意义(P值分别为0.028和0.013),ADCmean及ADC50%在三阴性型中预测PCR的ROC曲线下面积分别为0.800、0.842。当ADCmean取1.030×10-3 mm2/s、ADC50%取0.976×10-3 mm2/s作为截断点,诊断灵敏度分别为75.0%、80.0%,特异度均为83.3%。结论 峰度系数对预测HER2过表达型患者NAC后PCR具有一定的价值,ADC50%对预测三阴性乳腺癌NAC后PCR具有较高的应用价值。 相似文献
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Lin Lin Li Jienan Hu Yize Wang Han Marah Foday Ambrose Moseray Moses Kureshi Aliye Wang Chudong Zeye Moutanou Modeste Judes Zha Lagabaiyila 《International journal of legal medicine》2020,134(5):1659-1661
International Journal of Legal Medicine - A total of 550 individuals (265 males and 285 females) from Sierra Leone, a west-African coastal country, were genotyped using the Microreader™ 19X... 相似文献
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Alternate expressions for the current density on the shielding surface of a gradient coil are derived for cylindrical, planar, and hyperbolic gradient coils. For the planar and hyperbolic geometries, these expressions allow more rapid high-precision calculations of current densities than the conventional solution. 相似文献
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BackgroundPeriostin (POSTN) is an extracellular matrix protein that is overexpressed in lung cancer and is considered an effective diagnostic and prognostic biomarker for lung cancer. The purpose of this study was to investigate the diagnostic performance of POSTN and to further evaluate the diagnostic value of POSTN combined with carcinoembryonic antigen (CEA) and cancer ratio [CR: serum lactate dehydrogenase (LDH)/pleural effusion adenosine deaminase (PE ADA)] in lung cancer‐related malignant PE (MPE).MethodsA total of 108 patients with PE, including 54 with lung cancer and 54 with benign lung disease, were enrolled in this study. The POSTN levels of PE and serum were detected using an enzyme‐linked immunosorbent assay. Information on the expression of PE and serum CEA, serum LDH, and PE ADA was collected from medical records.ResultsThe levels of PE POSTN in MPE of patients with lung cancer were significantly higher than those in patients with benign PE (p < 0.0001). The receiver operating characteristic (ROC) curve indicated that the diagnostic sensitivity and specificity of PE POSTN for lung cancer‐related MPE were respectively 77.78% and 68.52% when the cutoff value was determined to be 53.45 ng/ml. The ROC curve analysis demonstrated that PE POSTN has a high diagnostic value in MPE associated with lung cancer [area under the curve (AUC) = 0.764], and the combination of PE POSTN, PE CEA, and CR can improve the diagnostic accuracy of lung cancer‐related MPE (AUC = 0.948).ConclusionPOSTN can be used as a potential marker for lung cancer‐related MPE diagnosis. 相似文献