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91.
Acute respiratory distress syndrome (ARDS) is accompanied by severe lung inflammation induced by various diseases. Despite the severity of symptoms, therapeutic strategies for this pathologic condition are still poorly developed. Interferon (IFN)-α is well known as an antiviral cytokine and low-dose IFN-α has been reported to show antiinflammatory effects. Therefore, we investigated how this cytokine affected ARDS in a mouse model. C57BL/6 mice received sequential intratracheal administration of α-galactosylceramide (α-GalCer) and lipopolysaccharide (LPS), which resulted in the development of fulminant ARDS. These mice were then treated intranasally with IFN-α and their survival, lung weight, pathological findings, and cytokine production were evaluated. Administration of low-dose IFN-α prolonged survival of fulminant ARDS mice, but higher doses of IFN-α did not. Histological analysis showed that low-dose IFN-α treatment improved findings of diffuse alveolar damage in fulminant ARDS mice, which was associated with reduction in the wet/dry (W/D) lung weight ratio. Furthermore, IFN-γ production in the lungs was significantly reduced in IFN-α-treated mice, compared with control mice, but tumor necrosis factor (TNF)-α production was almost equivalent for both groups. Low-dose IFN-α shows antiinflammatory and therapeutic effects in a mouse model of fulminant ARDS, and reduced production of IFN-γ in the lung may be involved in the beneficial effect of this treatment.  相似文献   
92.
Shielding, particularly of the gonads, has been a routine part of diagnostic radiographic imaging for many years. However, recent thinking suggests that such shielding may offer little benefit, and in some cases may actually cause harm, e.g. by obscuring anatomy or paradoxically increasing patient radiation dose secondary to the need for repeat imaging. This thinking has led many institutions in the West to abandon routine shielding. However, in Asia, shielding is still commonplace. It was felt that the Asia-Pacific Forum on Quality and Safety in Medical Imaging (APQS) was an ideal place to discuss the merits of shielding and deliver a pan-Asian consensus. The APQS is an annual meeting that convenes radiation safety and imaging quality experts from all of the major Asian regions. During the 2020 APQS meeting, radiation safety experts from each region discussed their opinions of shielding during a dedicated session. These experts’ views were mostly in line with the views of Western radiologists. However, important country specific and cultural factors were noted by each of the experts. A pan-Asian consensus was issued by the forum. It is hoped that this consensus will guide the development of future shielding policies throughout Asia.  相似文献   
93.
Odontology - Oral scanners allow dental impressions to be taken in a short time without the use of an impression material. However, it has been noted that high impression accuracy cannot be...  相似文献   
94.
Gastric adenocarcinoma of the fundic gland type (GAFG) and pyloric gland adenoma (PGA) have recently been recognized as rare types of neoplasia. We performed comparative immunohistochemical and genetic analyses of 3 GAFGs and 12 PGAs. All of the 3 GAFGs were diffusely positive for pepsinogen‐I, MIST1 and MUC6, indicating the predominantly chief cell/mucous neck cell differentiation of these tumors. A small number of H.K‐ATPase‐positive parietal cells were also scattered. PGAs invariably exhibited diffuse MUC6 and TFF2 expression, consistent with the pyloric gland differentiation of these tumors. Ten of the 12 PGAs also unexpectedly exhibited focal expression of pepsinogen‐I and MIST1, suggesting that PGAs often show focal chief cell differentiation and phenotypically resemble mucous neck cells rather than pyloric glands. The mutation analyses revealed activating GNAS mutations, which have been reported to be frequently detected in PGAs, in two of the GAFGs. While GAFGs and PGAs are morphologically distinct lesions, our observations showed their partially overlapping immunohistochemical profiles and shared presence of GNAS mutations, in addition to their common occurrence in the fundic gland mucosa. Based on these observations, we suggest that both GAFGs and PGAs are closely related lesions characterized by a mucous neck cell/chief cell lineage phenotype.  相似文献   
95.
Identifying the stages of sleep, or sleep staging, is an unavoidable step in sleep research and typically requires visual inspection of electroencephalography (EEG) and electromyography (EMG) data. Currently, scoring is slow, biased and prone to error by humans and thus is the most important bottleneck for large‐scale sleep research in animals. We have developed an unsupervised, fully automated sleep staging method for mice that allows less subjective and high‐throughput evaluation of sleep. Fully Automated Sleep sTaging method via EEG/EMG Recordings (FASTER) is based on nonparametric density estimation clustering of comprehensive EEG/EMG power spectra. FASTER can accurately identify sleep patterns in mice that have been perturbed by drugs or by genetic modification of a clock gene. The overall accuracy is over 90% in every group. 24‐h data are staged by a laptop computer in 10 min, which is faster than an experienced human rater. Dramatically improving the sleep staging process in both quality and throughput FASTER will open the door to quantitative and comprehensive animal sleep research.  相似文献   
96.
Journal of Natural Medicines - Saposhnikoviae Radix (SR) is a commonly used crude drug that is obtained from the root and rhizome of Saposhnikovia divaricata which is distributed throughout China,...  相似文献   
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Recipients for liver transplantation often have portosystemic shunts due to portal hypertension. It is an important problem whether such shunts should be ligated during operations. Ligating the shunts seems of benefit for increasing portal blood flow to the liver, but it is sometimes difficult technically, and it is invasive to the patient. We experienced a recipient with huge portosystemic shunts and no esophageal varices before living-related liver transplantation. Some shunts were ligated during operation to increase portal blood flow to the graft. Unfortunately, the patient suffered severe bleeding from esophagogastric varices after he underwent retransplantation owing to accidental liver failure. Based on our experience, extreme care should be exercised to avoid varicose bleeding after ligating the portosystemic shunts of liver transplantation patients.  相似文献   
100.
We describe a patient with persistent pure red cell aplasia due to human parvovirus B19 (HPVB19) infection during immunosuppressive therapy for refractory autoimmune hemolytic anemia (AIHA). The patient had been given corticosteroid (CS) and/or azathioprine for AIHA. During the course of treatment, reticulocyte count and hemoglobin levels decreased suddenly. Bone marrow aspirate showed erythroid lineage-specific aplasia with a few giant proerythroblasts, suggesting the presence of HPVB19 infection. The diagnosis of aplastic crisis due to HPVB19 infection was based on positive test results by polymerase chain reaction for HPVB19 immunoglobulin M (IgM) antibody and B19 DNA. Although splenectomy followed by administration of high-dose gamma globulin (HDIG) and plasma exchange were performed, the crisis and hemolysis recurred. Aplastic crises occurred several times when the B19 IgG result became negative and the CD4+ lymphocyte count was less than 300/microL. The patient showed complete recovery from anemia after CS was switched to cyclosporin A (CsA) and intermittent administration of HDIG. The result for B19 IgG antibody was continuously positive, and the DNA result became negative after these treatments. The results in this case indicated that concomitant administration of CsA and intermittent administration of HDIG can lead to cure of chronic anemia due to HPVB19 infection in patients with refractory AIHA.  相似文献   
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