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IntroductionNumerous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests exists commercially; however, their performance using clinical samples is limited. Although insufficient to detect SARS-CoV-2 in the early phase of infection, antibody assays can be of great use for surveillance studies or for some coronavirus disease 2019 (COVID-19) patients presenting late to the hospital.MethodsThis study evaluated the sensitivity and specificity of four commercial SARS-CoV-2 lateral flow antibody tests using 213 serum specimens from 90 PCR-positive confirmed COVID-19 patients. Of 59 negative control sera, 50 were obtained from patients with other respiratory infectious diseases before COVID-19 pandemic began while nine were from patients infected with other respiratory viruses, including two seasonal coronaviruses.ResultsThe varied sensitivities for the four commercial kits were 70.9%, 65.3%, 45.1%, and 65.7% for BioMedomics, Autobio Diagnostics, Genbody, and KURABO, respectively, between sick days 1 and 155 in COVID-19 patients. The sensitivities of the four tests gradually increased over time after infection before sick day 5 (15.0%, 12.5%, 15.0%, and 20.0%); from sick day 11–15 (95.7%, 87.2%, 53.2%, and 89.4%); and after sick day 20 (100%, 100%, 68.6%, and 96.1%), respectively. For severe illness, the sensitivities were quite high in the late phase after sick day 15. The specificities were over 96% for all four tests. No cross-reaction due to other pathogens, including seasonal coronaviruses, was observed.ConclusionsOur results demonstrated the large differences in the antibody test performances. This ought to be considered when performing surveillance analysis.  相似文献   
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Central hypothyroidism (CH) is defined as hypothyroidism due to insufficient stimulation of the thyroid gland by TSH, for which secretion or activity can be impaired at the hypothalamic or pituitary levels. Patients with CH frequently present with multiple other pituitary hormone deficiencies. In addition to classic CH induced by hypothalamic-pituitary tumors or Sheehan syndrome, novel causes include traumatic brain injury or subarachnoid hemorrhage, bexarotene (a retinoid X receptor agonist) therapy, neonates being born to mothers with insufficiently controlled Graves disease, and lymphocytic hypophysitis. Growth hormone therapy, which may be used in children and adults, is now also recognized as a possible cause of unmasking CH in susceptible individuals. In addition, mutations in genes, such as TRHR, POU1F1, PROP1, HESX1, SOX3, LHX3, LHX4 and TSHB, have been associated with CH. The difficulty in making a clear diagnosis of CH is that the serum TSH levels can vary; values are normal in most cases, but in some might be low or slightly elevated. Levels of endogenous T(4) in serum might also be subnormal. Appropriate doses of levothyroxine for T(4) replacement therapy have not been confirmed, but might need to be higher than presently used empirically in patients with CH and should be adjusted according to age and other hormone deficiencies, to achieve free T(4) concentrations in the upper end of the normal range.  相似文献   
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Hepatocyte growth factor (HGF) is a potent mitogen for vascular endothelial cells (EC); however, signal transduction pathways for HGF-stimulated EC growth remain unclear. In the present study we investigated the role of Src family kinases and nitric oxide (NO) in HGF-stimulated EC growth. Human umbilical vein endothelial cells (HUVEC) were stimulated with HGF and NO was measured by an NOx analyzing HPLC system. Activation of ERK1/2 and p38 MAPK was assessed by Western blot. NO production in HUVEC increased 1.8-fold by HGF. A Src family kinases inhibitor PP1 inhibited HGF-stimulated NO production by 71%. HUVEC growth increased 1.9-fold in cell number by HGF. PP1 and Nitro-L-arginine methylester (L-NAME) inhibited HGF-stimulated HUVEC growth by 51 and by 71%. ERK1/2 and p38 MAPK were phosphorylated by HGF and a MEK inhibitor PD98059 and a p38 MAPK inhibitor SB203580 inhibited HGF-stimulated HUVEC growth by 66% and by 58%; however, HGF-induced phosphorylation of ERK1/2 and p38 MAPK was not inhibited by L-NAME, indicating that NO is not an upstream activator of ERK1/2 and p38 MAPK. These findings demonstrated that Src family kinases regulate HGF-stimulated NO production in HUVEC and that HGF stimulates HUVEC growth through NO-dependent and NO-independent pathways.  相似文献   
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BACKGROUND/AIMS: Minimally invasive surgery, with its advantages of early return to normal activity and good cosmetic results, is an important goal in the treatment of patients with mucosal ulcerative colitis. The aim of this study was to compare outcomes utilizing a mini-laparotomy approach to total abdominal colectomy for mucosal ulcerative colitis with those of the conventional approach. METHODOLOGY: Eleven patients scheduled to undergo the first (total abdominal colectomy) of a 2 or 3-stage operation for mucosal ulcerative colitis via a mini-laparotomy between 1999 and 2001 were prospectively studied. The mini-laparotomy described here involves total abdominal colectomy performed through a skin incision shorter than 7 cm. Seven similar patients who underwent conventional laparotomy between 1995 and 1998 served as the control group. RESULTS: The mini-laparotomy approach was accomplished in 9 patients (81.8%). Patient characteristics between cases and controls were similar. Postoperative intervals until standing, walking, flatus, urinary catheter removal, and tolerance of solid diet were significantly shorter in the mini-laparotomy group (P = 0.031, P = 0.023, P = 0.0033, P = 0.0093, and P = 0.023, respectively). CONCLUSIONS: A mini-laparotomy approach to total abdominal colectomy appears feasible and safe in selected patient with mucosal ulcerative colitis and poses an attractive alternative to conventional laparotomy in patients similar to those presented here.  相似文献   
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A 22-year-old female was diagnosed as having acute lymphoid leukemia (ALL) in February 1995, from the findings of peroxidase negative, CD10+, CD19+, TdT+ and rearrangement of IgH and TCR beta. AdVP (doxorubicin, vincristine and prednisolone) therapy achieved a complete remission (CR). Bone marrow transplantation had to be abandoned because of the lack of an HLA-identical donor. Intensification therapy was thus carried out repeatedly. In June 1998, myeloblast with Auer rods, peroxidase positive, CD13+, CD33+ and HLA-DR+, appeared. The patient was diagnosed as having lineage switch acute myeloid leukemia (AML) from ALL. Though A-DMP (cytosine arabinoside, daunorubicin, 6-mercaptopurine) therapy was resistant, AdVP therapy led to a CR. The patient died of cardiotoxicity from anthracyclines in February 1999. From the results of the Ramasamy method using the clonal rearrangements of the Ig heavy chain gene locus, the origin of the pathological cells of ALL and AML was indicated to be the same leukemia clone.  相似文献   
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