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31.
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
32.
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   
33.
ContextThe sleep-promoting activity of Nelumbo nucifera Gaertn. (Nymphaeaceae) alkaloids in leaves or seeds are well known. However, the sleep-promoting activity of the lotus rhizome (LE), which is used mainly as food, has not yet been evaluated.ObjectiveWe investigated the sleep-promoting activity of LE water extract.Materials and methodsInstitute of Cancer Research (ICR) mice (n = 8) were subject to a pentobarbital-induced sleep test to assess changes in sleep latency and duration following the administration of LE (80–150 mg/kg). In addition, electroencephalography analysis was performed to determine the sleep quality after LE treatment as well as the sleep recovery effect of LE using a caffeine-induced insomnia SD rat model. Real-time PCR and western blot analysis were performed to investigate the expression of neurotransmitter receptors, and the GABAA receptor antagonists were used for receptor binding analysis.ResultsAn oral administration of 150 mg/kg LE significantly increased sleep duration by 24% compared to the control. Furthermore, LE increased nonrapid eye movement (NREM) sleep by increasing theta and delta powers. In the insomnia model, LE increased sleep time by increasing NREM sleep. Moreover, treatment with picrotoxin and flumazenil decreased the sleep time by 33% and 23%, respectively, indicating an involvement of the GABAA receptor in the sleep-enhancing activity of LE. The expression of GABAA receptors and the concentration of GABA in the brain were increased by LE.Discussion and conclusionsThe results suggest that the sleep-promoting activity of LE was via the GABAA receptor. Collectively, these data show that LE may promote sleep.  相似文献   
34.
Rationale:Transvaginal evisceration of the small bowel is an extremely rare condition after hysterectomy, which requires urgent surgical intervention to prevent serious bowel morbidity and mortality.Patient concerns:A 65-year-old woman presented with sudden-onset severe abdominal pain and a mass protruding through the vagina. The past surgical history was significant, with an abdominal hysterectomy for cervical cancer performed 11 weeks prior to presentation.Diagnosis:Pelvic examination revealed prolapsed small-bowel loops (18-20 cm in length). Pelvic computed tomography scan confirmed the presence of transvaginal evisceration of the small bowel.Interventions:Bowel reduction and urgent laparotomy were the selected treatment approaches for a detailed inspection and thorough washing of the intrα-abdominal cavity. A Foley catheter was inserted in the emergency room, with the subject in the lithotomy position. The prolapsed bowel loops spontaneously reduced without manual reduction, and the vault defect was repaired transvaginally.Outcomes:The patient experienced no postoperative complications and remained disease-free for 9months postoperatively.Lessons:Transvaginal evisceration of the small bowel should be considered a surgical emergency. A multidisciplinary approach to prompt case management involving clinicians in gynecology, general surgery, and emergency medicine is vital for preventing serious consequences. Hysterectomy is the most frequently performed gynecological surgical procedure, and evisceration occurs most often after hysterectomy. Therefore, patients should be informed about this rare but possible hysterectomy complication.  相似文献   
35.
Rationale:Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown etiology with diverse clinical and laboratory manifestations, including thrombocytopenia. About 25% of patients with SLE may be affected by thrombocytopenia, many of whom are asymptomatic. Some patients, however, experience platelet counts that drop quite low and predispose them to bleeding. Thrombotic thrombocytopenic purpura (TTP) is defined with a classic pentad of clinical features, such as thrombocytopenia, microangiopathic hemolytic anemia, neurological symptoms and signs, renal symptoms and signs, and fever. The association of TTP and SLE has been sporadically reported in the literature.Patient concerns and diagnosis:We describe a 16-year-old girl with SLE and immune thrombocytopenia, in whom TTP was diagnosed.Interventions and outcomes:She was treated with pulse methylprednisolone, whose platelet counts normalized after therapy with plasmapheresis and an anti-CD20 monoclonal antibody (rituximab).Conclusion:A pediatric patient with SLE and immune thrombocytopenia in whom TTP developed was treated with plasmapheresis and rituximab therapy successfully, though the patient experienced a disease relapsed after 18 months, which was controlled by the same management.  相似文献   
36.
用Boc-和Tos-基团分别保护氨基和侧链胍基,以1%交联度聚苯乙烯二苯甲氨基树脂为载体,用DCC固相法合成肽,HF断裂肽树脂键和去除侧链保护基团,粗产物经高效液相层析纯化,合成了心肌兴奋肽Phe-Met-Arg-Phe-NH_2及其类似物Phe-Pro-Arg-Phe-NH_2,并观察了此二种肽对大鼠血压和心率的影响。  相似文献   
37.
38.
PurposeTo evaluate the effect of classroom illuminance on the development and progression of myopia in elementary school children.MethodsThe daylight factor, a ratio of inside and outside illuminance, was obtained in 50 elementary schools. The first-grade students in the school with the lowest daylight (LD) factor (LD school, 145 subjects; 0.51%) and with the highest daylight (HD) factor (HD school, 147 subjects; 13.35%) were selected. A survey was conducted to evaluate parental myopia, the amount of near-work and outdoor activities. The refractive error and axial length (AL) were measured at initial and after 6 months. The spherical equivalent, AL, and the survey results were compared between the two schools. The mean AL of the emmetropic children was obtained, and all subjects were divided into two groups, more and less than mean AL. Changes in refractive errors and AL were also compared according to AL.ResultsThe amount of change in spherical equivalent and AL after 6 months were not different between the two schools. Initial prevalence of myopia was high in the HD school. However, it became similar between the two schools after 6 months. The mean AL of 155 emmetropic children was 22.7 ± 0.63 mm. In the 185 children with AL ≥22.7 mm, there was no difference in the AL change between the two schools. However, the change in AL in 107 children with AL <22.7 mm was significantly larger in the LD school (0.19 mm) than that in the HD school (0.15 mm, p = 0.049). Parental myopia, near-work and outdoor activities were not different between the two schools.ConclusionsHigh classroom illuminance during the day reduced axial elongation in eyes of children with a shorter AL. Increase in classroom light level by permitting more sunlight can be a protective measure against the development of myopia.  相似文献   
39.
Background:The purpose of this study was to investigate the effects of the meditation-based intervention on obsessive-compulsive disorder (OCD).Methods:The following databases were searched up to April 2021: the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, Medline (via PubMed), PsycARTICLES, 4 Korean databases (Korean Medical Database [KMbase], Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], and Oriental Medicine Advanced Searching Integrated System [OASIS]), and China National Knowledge Infrastructure (CNKI). The search terms related to meditation-based intervention and OCD were used. This systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The selected articles were evaluated using the Cochrane risk of bias tool. The Review Manager (RevMan) 5.4 was used to perform the meta-analysis.Results:In all, 16 randomized controlled trials were selected. The meta-analysis showed that the group receiving the treatment combining medication and meditation-based intervention for OCD showed a more significant post-treatment improvement in Yale-Brown obsessive compulsive scale than the group receiving medication only. Compared with other non-medication interventions that are known to be effective in treating OCD, the Yale-Brown obsessive compulsive scale showed a significant improvement immediately after the meditation-based intervention. However, no significant difference was found in the follow-up monitoring data across all examined cases.Conclusion:This study was conducted to verify the effects of meditation-based intervention on OCD. The results suggested that combined treatment with medication and meditation-based intervention was more effective in treating OCD than medication alone; the positive effects of meditation-based intervention may be greater than the effects of other non-medication interventions. However, the lack of significant difference in the follow-up indicates that long-term effect of meditation-based interventions is unclear.Trial registration number:PROSPERO CRD42021244408  相似文献   
40.
Noroviruses are associated with one fifth of diarrheal illnesses globally and are not yet preventable with vaccines. Little is known about the effects of norovirus infection on infant gut microbiome health, which has a demonstrated role in protecting hosts from pathogens and a possible role in oral vaccine performance. In this study, we characterized infant gut microbiome changes occurring with norovirus-associated acute gastroenteritis (AGE) and the extent of recovery. Metagenomic sequencing was performed on the stools of five infants participating in a longitudinal birth cohort study conducted in León, Nicaragua. Taxonomic and functional diversities of gut microbiomes were profiled at time points before, during, and after norovirus infection. Initially, the gut microbiomes resembled those of breastfeeding infants, rich in probiotic species. When disturbed by AGE, Gammaproteobacteria dominated, particularly Pseudomonas species. Alpha diversity increased but the genes involved in carbohydrate metabolism and glycan biosynthesis decreased. After the symptoms subsided, the gut microbiomes rebounded with their taxonomic and functional communities resembling those of the pre-infection microbiomes. In this study, during disruptive norovirus-associated AGE, the gut microbiome was temporarily altered, returning to a pre-infection composition a median of 58 days later. Our study provides new insights for developing probiotic treatments and furthering our understanding of the role that episodes of AGE have in shaping the infant gut microbiome, their long-term outcomes, and implications for oral vaccine effectiveness.  相似文献   
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