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981.
982.
We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.  相似文献   
983.
Ten new polyacetylenic alcohols (1-6, 8-11), along with a known compound, petrocortyne C (7), were isolated from the marine sponge Petrosia sp. The gross structures were established based on NMR and MS data, and the absolute configuration was determined by the modified Mosher's method. These compounds displayed considerable cytotoxicity against a small panel of human solid tumor cell lines. Compounds 1-11 were further evaluated for in vitro inhibitory activity on DNA replication.  相似文献   
984.
The antiviral effects of aqueous extracts of Terminalis chebula Retz., Sanguisorba officinalis L., Rubus coreanus Miq. and Rheum palmatum L. were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. The extracts were assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. All extracts decreased the levels of extracellular HBV virion DNA at concentrations ranging from 64 to 128 microg/mL and inhibited the secretion of HBsAg dose dependently. Of the four tested plants, Terminalis chebula exhibited the most prominent anti-HBV activities.  相似文献   
985.
Seselidiol [1], a new polyacetylene, has been isolated from the roots of Seseli mairei. On the basis of chemical and spectroscopic evidence, its structure has been established as heptadeca-1,8(Z)-diene-4,6-diyne-3,10-diol. Seselidiol and its acetate have been demonstrated to show moderate cytotoxicity against KB, P-388, and L-1210 tumor cells.  相似文献   
986.
We investigated the effects of the water soluble fraction of Terminalia chebula (Combretaceae) (WFTC) on systemic and local anaphylaxis. WFTC administered 1h before compound 48/80 injection inhibited compound 48/80-induced anaphylactic shock 100% with doses of 0.01-1.0 g/kg. When WFTC was administered 5 or 10 min after compound 48/80 injection, the mortality also decreased in a dose-dependent manner. Passive cutaneous anaphylaxis was inhibited by 63.5+/-7.8% by oral administration of WFTC (1.0 g/kg). When WFTC was pretreated at concentrations ranging from 0.005 to 1.0 g/kg, the serum histamine levels were reduced in a dose-dependent manner. WFTC (0.01-1.0 mg/ml) also significantly inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. However, WFTC (1.0 mg/ml) had a significant increasing effect on anti-dinitrophenyl IgE-induced tumor necrosis factor-alpha production from RPMC. These results indicate that WFTC may possess a strong antianaphylactic action.  相似文献   
987.
Suhyun Lee 《RSC advances》2022,12(35):22911
This study attempted to develop a superhydrophobic conductive fabric to solve the problem of functional deterioration due to oxidation of conductive fabrics. To this end, a superhydrophobic surface was achieved by introducing nano-roughness to the surface of the polyester-conductive fabric by using alkaline hydrolysis, and then lowering the surface energy through hydrophobic coating. In order to derive optimal processing conditions with excellent superhydrophobicity while maintaining conductivity and mechanical properties, changes in surface structure, conductivity, superhydrophobicity and durability of conductivity against air and water were evaluated according to alkaline hydrolysis duration. As the alkaline hydrolysis duration increased, the polyester surface was etched and the silver oxide particles formed on the conductive yarns, creating non-uniform nano-roughness. The weight, tensile strength, and strain of the conductive fabric decreased due to alkaline hydrolysis, and the change was noticeable after 30 min of alkaline hydrolysis. In addition, as the alkaline hydrolysis duration increased, the surface resistance of the conductive fabric slightly increased and the surface temperature by electric heating performance decreased, but it still showed excellent conductivity. After 30 min of alkaline hydrolysis, a contact angle of more than 150° and a shedding angle of less than 10° achieved a superhydrophobic surface. This superhydrophobic surface prevented the reaction of silver with air or water in spite of prolonged exposure to air and repeated contact with water to maintain electrical properties, thereby improving the durability of conductivity. This study is significant in that it achieved dual roughness for superhydrophobicity on the surface of conductive fabrics using a relatively easy and simple method by applying alkaline hydrolysis, which is commonly used with polyester fabric. Therefore, it is expected to solve the problem of conductivity loss of the use of conductive fabric in various environments.

A superhydrophobic conductive fabric is developed to solve the problem of functional deterioration due to oxidation by air and water through alkaline hydrolysis and hydrophobic coating.  相似文献   
988.
989.
ObjectivesThis study evaluated the response in Daegu, Korea to the first wave of the coronavirus disease 2019 (COVID-19) pandemic according to a public health emergency response model.MethodsAfter an examination of the official data reported by the city of Daegu and the Korea Centers for Disease Control and Prevention, as well as a literature review and advisory meetings, we chose a response model. Daegu’s responses were organized into 4 phases and evaluated by applying the response model.ResultsIn phase 1, efforts were made to block further transmission of the virus through preemptive testing of a religious group. In phase 2, efforts were concentrated on responding to mass infections in high-risk facilities. Phase 3 involved a transition from a high-intensity social distancing campaign to a citizen participation–based quarantine system. The evaluation using the response model revealed insufficient systematic preparation for a medical surge. In addition, an incorporated health-related management system and protection measures for responders were absent. Nevertheless, the city encouraged the participation of private hospitals and developed a severity classification system. Citizens also played active roles in the pandemic response by practicing social distancing.ConclusionsThis study employed the response model to evaluate the early response in Daegu to the COVID-19 pandemic and revealed areas in need of improvement or maintenance. Based on the study results, creation of a systematic model is necessary to prepare for and respond to future public health emergencies like the COVID-19 pandemic.  相似文献   
990.
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