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1.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
2.
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.  相似文献   
3.
928株革兰阴性杆菌耐药性监测   总被引:27,自引:4,他引:23  
目的:了解青岛地区临床分离的重要革兰阴性杆菌的耐药情况以指导合理用药。方法:2001年青岛3家医院临床分离的5种革兰阴性杆菌用Kirby-Bauer法进行药敏试验。结果:5种病原菌均占3家医院革兰阴性杆菌分离率的前5位,大肠埃希菌对氟喹诺酮类药物的耐药率达60%-87%,细菌对亚胺培南均呈高度敏感,但铜绿假单胞菌耐亚胺培南株占25.8%,头孢他啶的抗菌活性是三代头孢菌素中最高的;复方酶抑制剂表现出良好的抗菌活性。结论:细菌耐药问题仍是目前临床的严重问题,地域性的耐药性监测是必要的。  相似文献   
4.
5.
OBJECTIVE: To assess the impact and cost-effectiveness of two information-based provider reminder interventions designed to improve self-care management and outcomes of heart failure (HF) patients. DATA SOURCES/STUDY SETTING: Interview and agency administrative data on 628 home care patients with a primary diagnosis of HF. STUDY DESIGN: Patients were treated by nurses randomly assigned to usual care or one of two intervention groups. The basic intervention was an e-mail to the patient's nurse highlighting six HF-specific clinical recommendations. The augmented intervention supplemented the initial nurse reminder with additional clinician and patient resources. DATA COLLECTION: Patient interviews were conducted 45 days post admission to measure self-management behaviors, HF-specific outcomes (Kansas City Cardiomyopathy Questionnaire-KCCQ), health-related quality of life (EuroQoL), and service use. PRINCIPAL FINDINGS: Both interventions improved the mean KCCQ summary score (15.3 and 12.9 percent, respectively) relative to usual care (p< or =.05). The basic intervention also yielded a higher EuroQoL score relative to usual care (p< or =.05). In addition, the interventions had a positive impact on medication knowledge, diet, and weight monitoring. The basic intervention was more cost-effective than the augmented intervention in improving clinical outcomes. CONCLUSIONS: This study demonstrates the positive impact of targeting evidence-based computer reminders to home health nurses to improve patient self-care behaviors, knowledge, and clinical outcomes. It also advances the field's limited understanding of the cost-effectiveness of selected strategies for translating research into practice.  相似文献   
6.
Klippel-Feil syndrome (KFS) is a heterogeneous entity, characterized by specific congenital anomalies of segmentation of the cervical spine. We report a case of KFS plus atretic meningocele in one identical twin and anencephaly in the other. These identical twins were both male with no chromosome defect. One of them had anencephaly diagnosed at the gestational age of 17 weeks and died soon after birth, whereas the co-twin had KFS with multiple congenital anomalies including short neck with low hairline, occipital atretic meningocele, butterfly vertebrae, hemivertebrae, cervico-thoracic scoliosis, left thumb preaxial polydactyly, and right undescended testis. He received rehabilitation during infancy and could walk at the age of 15 months. Both of these infants had preaxial polydactyly, which is an uncommon anomaly associated with KFS. In conclusion, iniencephaly and anencephaly are probably the extreme manifestations of KFS rather than different dysraphisms. Prompt clinical suspicion with early diagnostic imaging for spine lesions and occult opening of neural tube is mandatory for further intervention and rehabilitation.  相似文献   
7.
8.
An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R2=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC50 is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164.  相似文献   
9.
10.
目的:探讨细胞活素肿瘤坏死因子-α(TNF-α)、SNAP(S-Nitroso-Nacetyl-penicillamine)对胰腺癌细胞产生血管内皮生长因子A、C(VEGF-A、C)的调节.方法:用Northern杂交和Western杂交法分析6种人胰腺癌细胞株中VEGF-A、C基因和蛋白的表达;以TNF-α或SNAP刺激其中两个细胞株后用逆转录-聚合酶链式反应技术(RT-PCR)分析其VEGF-A、C基因的表达.结果:Northern杂交法显示这6种胰腺癌细胞株均有4.1kb VEGF-A基因和2.4kb VEGF-C基因的表达;Western杂交法显示它们均有分子量为43kD的VEGF-A蛋白质和分子量为55kD的VEGF-C蛋白质的表达.RT-PCR分析法显示:TNF-α使细胞株COLO-357产生VEGF-A、VEGF-C mRNA分别减少约1~2.5倍、1~2倍,使细胞株CAPAN-1产生VEGF-A、VEGF-C mRNA分别减少约1倍、1.6~2.5倍;而SNAP刺激细胞株COLO-357产生VEGF-A mRNA增加约5倍,刺激细胞株CAPAN-1产生VEGF-A mRNA增加约4倍,但对这两种细胞株产生VEGF-C mRNA均无明显刺激作用.结论:细胞活素TNF-α和低氧通过调节血管内皮生长因子A、C的表达而影响胰腺癌细胞的生物学特性,抑制癌细胞的增殖,促进其凋亡、死亡或进展、恶化.  相似文献   
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