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991.
Alveolar epithelial beta-adrenergic receptor (betaAR) activation accelerates active Na+ transport in lung epithelial cells in vitro and speeds alveolar edema resolution in human lung tissue and normal and injured animal lungs. Whether these receptors are essential for alveolar fluid clearance (AFC) or if other mechanisms are sufficient to regulate active transport is unknown. In this study, we report that mice with no beta1- or beta2-adrenergic receptors (beta1AR-/-/beta2AR-/-) have reduced distal lung Na,K-ATPase function and diminished basal and amiloride-sensitive AFC. Total lung water content in these animals was not different from wild-type controls, suggesting that betaAR signaling may not be required for alveolar fluid homeostasis in uninjured lungs. Comparison of isoproterenol-sensitive AFC in mice with beta1- but not beta2-adrenergic receptors to beta1AR-/-/beta2AR-/- mice indicates that the beta2AR mediates the bulk of beta-adrenergic-sensitive alveolar active Na+ transport. To test the necessity of betaAR signaling in acute lung injury, beta1AR-/-/beta2AR-/-, beta1AR+/+/beta2AR-/-, and beta1AR+/+/beta2AR+/+ mice were exposed to 100% oxygen for up to 204 hours. beta1AR-/-/beta2AR-/- and beta1AR+/+/beta2AR-/- mice had more lung water and worse survival from this form of acute lung injury than wild-type controls. Adenoviral-mediated rescue of beta2-adrenergic receptor (beta2AR) function into the alveolar epithelium of beta1AR-/-/beta2AR-/- and beta1AR+/+/beta2AR-/- mice normalized distal lung beta2AR function, alveolar epithelial active Na+ transport, and survival from hyperoxia. These findings indicate that betaAR signaling may not be necessary for basal AFC, and that beta2AR is essential for the adaptive physiological response needed to clear excess fluid from the alveolar airspace of normal and injured lungs.  相似文献   
992.
Ge Z  Zhang Y  Ji X  Fan D  Duran CM 《Clinical cardiology》1992,15(11):818-824
Pulmonary hypertension is an important determinant of the clinical presentation of and surgical approach to patients with heart disease. To confirm the utility of continuous wave Doppler echocardiography in assessing the pulmonary artery diastolic pressure in patients with pulmonary regurgitation, 51 patients representing the wide hemodynamic spectrum of pulmonary artery pressure underwent simultaneous determination of pulmonary artery diastolic pressure by continuous wave Doppler echocardiography and cardiac catheterization. Pulmonary artery diastolic pressure was estimated from the Doppler recordings by the end-diastolic pressure gradient obtained by the modified Bernoulli equation plus the estimated right atrial pressure. A correlation was observed (r = 0.935, SEE = 7.4 mmHg) between Doppler and catheterization pulmonary artery diastolic pressure. In addition, comparison between the mean diastolic pressure gradient across the pulmonary valve by Doppler and pulmonary artery diastolic pressure at catheterization yielded a high correlation (r = 0.947, SEE = 5.1 mmHg). These data demonstrate that continuous wave Doppler echocardiography is a useful noninvasive technique for evaluating the pulmonary artery diastolic pressure in patients with pulmonary regurgitation.  相似文献   
993.
A field study in northeastern Inner Mongolia, People's Republic of China, in June of 1985 demonstrated a spotted fever group rickettsiosis. Two strains of spotted fever group rickettsiae were isolated. One strain was obtained from the blood of a patient with an eschar, regional lymphadenopathy, and history of a recent tick bite. The other strain originated from ova of ticks, Dermacentor nuttalli. These represent the second isolate of a spotted fever group rickettsia from a human and the first isolate from tick ova in the People's Republic of China. Antibodies to these rickettsiae were demonstrated by indirect immunofluorescence in the sera of 4% of healthy children and 34% of healthy human adults, in 58% of sheep, and in 76% of cattle in the same location. Hemolymph test revealed rickettsiae in 6 of 36 D. nuttalli examined.  相似文献   
994.
不同碘摄入量对甲状腺肿和甲状腺结节影响的前瞻性研究   总被引:1,自引:0,他引:1  
目的 研究不同碘摄入量人群非毒性甲状腺肿(甲肿)和非毒性甲状腺结节的流行病学特点及影响其发生、发展和转归的因素.方法 2004年对盘山(长期轻度碘缺乏)、彰武(碘缺乏基础上补碘至碘超足量)和黄骅(长期碘过量)社区于1999年参加本课题组流行病学研究并进行甲状腺B超检查的人群(3 385人)进行甲状腺疾病的随访调查.结果 (1)盘山、彰武和黄骅社区弥漫型甲肿的累积发病率分别为7.1%、4.4%和6.9%,盘山和黄骅均显著高于彰武(均P<0.01);结节型甲肿的累积发病率分别为5,0%、2.4%和0.8%,盘山的发病率最高(P<0.01).(2)三社区甲状腺单发结节的累积发病率分别为4.0%、5.7%和5.6%,多发结节的累积发病率分别为0.4%、1.2%和1.0%.(3)基础碘缺乏、碘过量、甲状腺自身抗体(thyroid autoantibody,TAA)阳性是甲肿发生的独立危险因素.(4)彰武初访时TAA阳性人群非毒性甲肿的发生率显著高于TAA阴性人群(P<0.01),盘山和黄骅无显著差异.(5)三社区非毒性弥漫型甲肿维持人群和黄骅非毒性结节型甲肿维持人群随访前后TAA阳性率均高于同社区正常人群(P<0.05).结论 碘缺乏和碘过量均有可能使甲肿的发病率增加.碘缺乏社区结节型甲肿高发,弥漫型甲肿是碘过量社区甲肿发牛的主要形式.甲状腺自身免疫与甲肿的发生和维持相关,这种相关性在历史上为碘缺乏而后过度补碘的社区更明显.  相似文献   
995.
干细胞(stem cell,SC)是一群结构和功能未特化的原始细胞,具有长期自我更新潜能和产生至少一种终末分化细胞的能力.而肠干细胞是位于小肠隐窝下部潘氏细胞上方及结直肠隐窝的底部的成体干细胞,具有增殖和自我维持、能产生许多子代细胞并能在受损伤后再生的特性.近年较多的文献报道结直肠癌组织中存在肿瘤干细胞,而这些具有干细胞特性的瘤细胞可能来自突变的肠干细胞,本文就肠干细胞和结直肠癌肿瘤干细胞的研究进展作一综述.  相似文献   
996.
目的研究克州静脉血栓栓塞症(VTE)的危险因素和发病特征。 方法分析我院近3年收治的VTE患者的临床资料。根据是否与住院及手术相关,分为医院相关性VTE(HA VTE)和社区相关性VTE(CA VTE)。调查患者的VTE危险因素,分析不同部位类型的下肢深静脉血栓形成(DVT)合并下腔静脉血栓或肺血栓栓塞症(PTE)的差异。 结果共纳入81例VTE患者,其中CA VTE 63例,HA VTE 18例,前者是后者的3.5倍。CA VTE的危险因素以肥胖(28.57%)、创伤或骨折(19.05%)、卧床(17.46%)为主,尚有15.87%的病例未能明确危险因素。HA VTE的危险因素以外科手术(66.67%)为主,其中又以骨科(6例)、妇产科手术(2例)最为常见。左下肢、右下肢、双侧下肢DVT的构成比分别为62.96%、34.57%、2.47%,差异有统计学意义(P < 0.05)。合并PTE的概率,双侧下肢DVT为100%,右下肢为32.14%,左下肢为13.72%,差异有统计学意义(P < 0.05)。 结论克州地区CA VTE较HA VTE常见,前者的主要危险因素是肥胖、创伤或骨折、卧床,后者为外科手术,并以骨科、妇产科手术最为常见。  相似文献   
997.
998.
999.
Wen  Hanjie  Wu  Wei  Fan  Fei  Liao  Peixi  Chen  Hu  Zhang  Yi  Deng  Zhenhua  Lv  Weiqiang 《International journal of legal medicine》2022,136(4):1067-1074

Human identification plays a significant role in the investigations of disasters and criminal cases. Human identification could be achieved quickly and efficiently via 3D sphenoid sinus models by customized convolutional neural networks. In this retrospective study, a deep learning neural network was proposed to achieve human identification of 1475 noncontrast thin-slice CT scans. A total of 732 patients were retrieved and studied (82% for model training and 18% for testing). By establishing an individual recognition framework, the anonymous sphenoid sinus model was matched and cross-tested, and the performance of the framework also was evaluated on the test set using the recognition rate, ROC curve and identification speed. Finally, manual matching was performed based on the framework results in the test set. Out of a total of 732 subjects (mean age 46.45 years ± 14.92 (SD); 349 women), 600 subjects were trained, and 132 subjects were tested. The present automatic human identification has achieved Rank 1 and Rank 5 accuracy values of 93.94% and 99.24%, respectively, in the test set. In addition, all the identifications were completed within 55 s, which manifested the inference speed of the test set. We used the comparison results of the MVSS-Net to exclude sphenoid sinus models with low similarity and carried out traditional visual comparisons of the CT anatomical aspects of the sphenoid sinus of 132 individuals with an accuracy of 100%. The customized deep learning framework achieves reliable and fast human identification based on a 3D sphenoid sinus and can assist forensic radiologists in human identification accuracy.

  相似文献   
1000.
Fan  Haoliang  Wang  Lingxiang  Liu  Changhui  Lu  Xiaoyu  Xu  Xuding  Ru  Kai  Qiu  Pingming  Liu  Chao  Wen  Shao-Qing 《International journal of legal medicine》2022,136(2):447-464
International Journal of Legal Medicine - Short tandem repeats (STRs) are the preferred genetic markers in forensic DNA analysis, routinely measured by capillary electrophoresis (CE) method based...  相似文献   
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