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1.
Mouse monoclonal antibodies to Hepatitis B surface antigen(HBsAg) were prepared and their functional capabilities tested by the method of solid phase enzyme linked immuno sorbent assay(ELISA). HBsAg binding studies indicated that one monoclonal antibody 6E-1-1 bound more HBsAg at a faster rate than the other monoclonal antibodies. Also, for the binding inhibition studies with the selected monoclonal antibody 6E-1-1, one monoclonal antibody 8D-3-6 didn’t exhibit binding inhibition for HBsAg. Then, a simultaneous ELISA method was developed for the immunodiagnosis of HBsAg. Different combinations of two monoclonal antibodies as solid phase and horseradish peroxidase(HRPO) labeled phase were studied. The combination of monoclonal antibody of higher affinity constant (6E-1-1) immobilized in a solid phase and monoclonal antibody of lower affinity constant (8D-3-6) as a HRPO labeled phase was more sensitive when two monoclonal antibodies of different affinity constants for HBsAg were prepared.  相似文献   
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Factors affecting the registration error (RE) and motion of focal hepatic lesions (FHLs) in image fusion of real-time ultrasonography (US) with computed tomography (CT) images were prospectively assessed by focusing on respiratory movement and FHL location. Real-time US and pre-acquired CT images at end-inspiration were fused with FHLs for 103 patients. Three-dimensional US data containing FHLs were obtained during end-inspiratory/expiratory phases. Multivariate analysis revealed that diaphragm motion (p < 0.001), chronic liver disease (p = 0.02) and the absolute difference in distance between the FHL and the central portal vein (CPV) during respiration (p = 0.03) were the independent factors that revealed the maximum effect on RE. In contrast, diaphragm motion (p < 0.001) and distance between the FHL and CPV at inspiration (p = 0.036) revealed the maximum effect on FHL motion. In conclusion, RE and FHL motion are affected by the degree of respiratory movement and the location of the FHL. Therefore, image fusion with CT images should be used with caution if the degree of respiratory motion is significant or if the FHL is located at the periphery of the liver.  相似文献   
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Impaired sleep can contribute to conditions such as cardiometabolic disorders, depression, and decreased immune function. Mothers of children with developmental disabilities (DDs) may be at greater risk for impaired sleep due to the sleep problems of their children. This cross-sectional study described the self-reported sleep characteristics of mothers of children (ages 6-12) with DDs by using a sleep diary and the Pittsburgh Sleep Quality Index (PSQI) as quantitative and qualitative measures of sleep in these mothers. The Consensus Sleep Diary was modified to ascertain how the child's sleep and needs for care during the night impacted the mother's sleep. The results showed that mothers had short sleep duration (nearly 40% slept <7 hours per night), woke up an average of 2.2 times per night (most commonly due to caregiving needs of children), and had poor sleep quality (mean PSQI global score of 7.9 [SD=4.8]). The sleep problems of children with DDs may influence mothers’ sleep.  相似文献   
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Intestinal obstruction involves a partial or complete blockage of the bowel which results in the failure of intestinal contents to pass through. The mechanical causes of obstruction may include the followings: hernias, postoperative adhesions or scar tissue, impacted feces, gallstones, tumors, granulomatous processes, intussusception, volvulus, foreign bodies, and etc. Hernias are the third leading cause of intestinal obstruction by 10% approximately. However, most hernias are the cases with abdominal wall, inguinal or internal hernia. Femoral, obturator, lumbar, or sciatic hernia as the cause of obsturction is rare. Furthermore, the cases accompanying soft tissue necrosis are seldomly reported. Herein, we report a case of intestinal obstruction caused by strangulated femoral hernia accompanying soft tissue necrosis in a 78-years-old female patient.  相似文献   
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Klouda  Timothy  Hao  Yuan  Kim  Hyunbum  Kim  Jiwon  Olejnik  Judith  Hume  Adam J.  Ayyappan  Sowntharya  Hong  Xuechong  Melero-Martin  Juan  Fang  Yinshan  Wang  Qiong  Zhou  Xiaobo  Mühlberger  Elke  Jia  Hongpeng  Padera  Robert F.  Raby  Benjamin A.  Yuan  Ke 《Angiogenesis》2022,25(2):225-240

Severe viral pneumonia caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by a hyperinflammatory state typified by elevated circulating pro-inflammatory cytokines, frequently leading to potentially lethal vascular complications including thromboembolism, disseminated intracellular coagulopathy and vasculitis. Though endothelial infection and subsequent endothelial damage have been described in patients with fatal COVID-19, the mechanism by which this occurs remains elusive, particularly given that, under naïve conditions, pulmonary endothelial cells demonstrate minimal cell surface expression of the SARS-CoV-2 binding receptor ACE2. Herein we describe SARS-CoV-2 infection of the pulmonary endothelium in postmortem lung samples from individuals who died of COVID-19, demonstrating both heterogeneous ACE2 expression and endothelial damage. In primary endothelial cell cultures, we show that SARS-CoV-2 infection is dependent on the induction of ACE2 protein expression and that this process is facilitated by type 1 interferon-alpha (IFNα) or -beta(β)—two of the main anti-viral cytokines induced in severe SARS-CoV-2 infection—but not significantly by other cytokines (including interleukin 6 and interferon γ/λ). Our findings suggest that the stereotypical anti-viral interferon response may paradoxically facilitate the propagation of COVID-19 from the respiratory epithelium to the vasculature, raising concerns regarding the use of exogenous IFNα/β in the treatment of patients with COVID-19.

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10.
Seasonal influenza vaccination elicits a diminished adaptive immune response in the elderly, and the mechanisms of immunosenescence are not fully understood. Using Ig-Seq, we found a marked increase with age in the prevalence of cross-reactive (CR) serum antibodies that recognize both the H1N1 (vaccine-H1) and H3N2 (vaccine-H3) components of an egg-produced split influenza vaccine. CR antibodies accounted for 73% ± 18% of the serum vaccine responses in a cohort of elderly donors, 65% ± 15% in late middle-aged donors, and only 13% ± 5% in persons under 35 years of age. The antibody response to non-HA antigens was boosted by vaccination. Recombinant expression of 19 vaccine-H1+H3 CR serum monoclonal antibodies (s-mAbs) revealed that they predominantly bound to non-HA influenza proteins. A sizable fraction of vaccine-H1+H3 CR s-mAbs recognized with high affinity the sulfated glycans, in particular sulfated type 2 N-acetyllactosamine (Galβ1-4GalNAcβ), which is found on egg-produced proteins and thus unlikely to contribute to protection against influenza infection in humans. Antibodies against sulfated glycans in egg-produced vaccine had been identified in animals but were not previously characterized in humans. Collectively, our results provide a quantitative basis for how repeated exposure to split influenza vaccine correlates with unintended focusing of serum antibody responses to non-HA antigens that may result in suboptimal immunity against influenza.  相似文献   
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