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排序方式: 共有363条查询结果,搜索用时 31 毫秒
1.
The tools available for monitoring necrotic enteritis caused by Clostridium perfringens in broiler chickens have been limited, particularly for identifying subclinical disease. In this study, a modified enzyme-linked immunosorbent assay was used to quantify levels of specific immunoglobulin G to C. perfringens alpha-toxin in serum from broilers. We found significantly higher antibody levels in broilers with a history of subclinical necrotic enteritis compared with a zinc-bacitracin-treated group with a low level of gut lesions. Furthermore, in 4.5-week-old commercial broiler flocks, there was an association between the occurrence of C. perfringens-associated hepatitis at slaughter and the immune response to alpha-toxin. Practical solutions for defining cut-off levels for positive serum samples at individual and flock levels are proposed, and were found to be useful on a set of samples available from flocks with different histories regarding the occurrence of C. perfringens-associated disease. This serological approach seems promising as a diagnostic tool in research and disease monitoring regarding C. perfringens-associated disease.  相似文献   
2.
Critical Incident Stress Debriefings have become an intervention method used in various cultures, countries and groups following critical incidents. Although the structure of such meetings has been adequately described, utilization of the group processes involved has received less attention. A model, process debriefing (PD), based on experiences from Europe, is presented. Some differences between the current CISD process in the United States and the Europe based model are outlined. Various factors that impact the process of debriefings are discussed with a special emphasis on leadership, and implications of these group process variables for psychological debriefing are presented. It is emphasized that the continued exploration and discussion of process issues is critical to advance the understanding of the critical elements of debriefing.  相似文献   
3.
Decreased aminoacylation of mutant tRNAs in MELAS but not in MERRF patients   总被引:3,自引:1,他引:3  
Mutations in human mitochondrial tRNA genes are associated witha number of multisystemic disorders. Using an assay that combinestRNA oxidation and circularization we have determined the relativeamounts and states of aminoacylation of mutant and wild-typetRNAs in tissue samples from patients with MELAS syndrome (mito-chondrial myopathy, encephalopathy, lactic acidosis, stroke-likeepisodes) and MERRF syndrome (myoclonus epilepsy with raggedred fibers), respectively. In most, but not all, biopsies fromMELAS patients carrying the A3243G substitution in the mitochondrialtRNALeu(UUR) gene, the mutant tRNA is under-represented amongprocessed and/or aminoacylated tRNAs. In contrast, in biopsiesfrom MERRF patients harboring the A8344G substitution in thetRNALys gene neither the relative abundance nor the aminoacylationof the mutated tRNA is affected. Thus, whereas the A3243G mutationmay contribute to the pathogenesis of MELAS by reducing theamount of aminoacylated tRNALeu, the A8344G mutation does notaffect tRNALys function in the same way. + To whom correspondence should be addressed. Tel: +1 617 4954396; Fax: +1 617 495 0758; Email: boerner@fas.harvard.edu  相似文献   
4.
The aim of the study was to compare neuromuscular activation in the gluteus maximus, the biceps femoris and the erector spinae from the Romanian deadlift, the 45-degree Roman chair back extension and the seated machine back extension. Fifteen resistance-trained females performed three repetitions with 6-RM loading in all exercises in a randomized and counterbalanced order. The activation in the whole movement as well as its lower and upper parts were analyzed. The results showed that the Romanian deadlift and the Roman chair back extension activated the gluteus maximus more than the seated machine back extension (94-140%, p < 0.01). For the biceps femoris the Roman chair elicited higher activation compared to both the Romanian deadlift and the seated machine back extension (71-174%). Further, the Romanian deadlift activated the biceps femoris more compared to the seated machine back extension (61%, p < 0.01). The analyses of the different parts of the movement showed that the Roman chair produced higher levels of activation in the upper part for both the gluteus maximus and the biceps femoris, compared to the other exercises. There were no differences in activation of the erector spinae between the three exercises (p = 1.00). In conclusion, both the Roman deadlift and the Roman chair back extension would be preferable to the seated machine back extension in regards to gluteus maximus activation. The Roman chair was superior in activating the biceps femoris compared to the two other exercises. All three exercises are appropriate selections for activating the lower back muscles. For overall lower limb activation, the Roman chair was the best exercise.Key points
  • In general, the Roman chair back extension lead to superior muscle activation compared to the Romanian deadlift and the seated machine back extension
  • The seated machine back extension showed the lowest gluteus and hamstring activation
  • All three exercises are appropriate selections for activating the lower back muscles
  • The differences in muscle activation are most likely caused by biomechanical differences.
Key words: Gluteus maximus, biceps femoris, erector spinae, muscle activation  相似文献   
5.
Objective: Needle acupuncture in small children has gained some acceptance in Western medicine. It is controversial, as infants and toddlers are unable to consent to treatment. We aimed to assess its efficacy for treating infantile colic.

Design: A systematic review and a blinding-test validation based on individual patient data from randomised controlled trials. Primary end-points were crying time at mid-treatment, at the end of treatment and at a 1-month follow-up. A 30-min mean difference (MD) in crying time between acupuncture and control was predefined as a clinically important difference. Pearson’s chi-squared test and the James and Bang indices were used to test the success of blinding of the outcome assessors [parents].

Eligibility criteria and data sources: We included randomised controlled trials of acupuncture treatments of infantile colic. Systematic searches were conducted in Cochrane CENTRAL, MEDLINE, EMBASE, CINAHL and AMED, and in the Chinese language databases CNKI, VIP, Wang fang, SinoMed and Chinese Clinical Trial Registry.

Results: We included three randomised controlled trials with data from 307 participants. Only one of the included trials obtained a successful blinding of the outcome assessors in both the acupuncture and control groups. The MD in crying time between acupuncture intervention and no acupuncture control was ?24.9?min [95% confidence interval, CI ?46.2 to ?3.6; three trials] at mid-treatment, ?11.4?min [95% CI ?31.8 to 9.0; three trials] at the end of treatment and ?11.8?min [95% CI ?62.9 to 39.2; one trial] at the 4-week follow-up. The corresponding standardised mean differences [SMDs] were ?0.23 [95% CI ?0.42 to ?0.06], ?0.10 [95% CI ?0.29 to 0.08] and ?0.09 [95% CI ?0.48 to 0.30]. The heterogeneity was negligible in all analyses. The statistically significant result at mid-treatment was lost when excluding the apparently unblinded study in a sensitivity analysis: MD ?13.8?min [95%CI ?37.5 to 9.9] and SMD ?0.13 [95%CI ?0.35 to 0.09]. The registration of crying during treatment suggested more crying during acupuncture [odds ratio 7.7; 95% CI 2.7–20.6; one trial]. GRADE-Moderate quality evidence.

Conclusions: Percutaneous needle acupuncture treatments should not be recommended for infantile colic on a general basis.

Systematic review registration: PROSPERO 2015:CRD42015023253
  • Key points
  • The role of acupuncture in the treatment of infantile colic is controversial. Available trials are small and present conflicting results.

  • There were no clinically important differences between infants receiving acupuncture and no acupuncture control in this IPD meta-analysis of randomised controlled trials.

  • The data indicate that acupuncture induces some treatment pain in many of the children.

  • The study results indicate that percutaneous needle acupuncture should not be recommended for treatment of infantile colic on a general basis.

  相似文献   
6.
White matter hyperintensities (WMHs) are associated with vascular risk and Alzheimer’s disease. In this study, we examined relations between WMH load and distribution, amyloid pathology and vascular risk in 339 controls and cases with either subjective (SCD) or mild cognitive impairment (MCI). Regional deep (DWMH) and periventricular (PWMH) WMH loads were determined using an automated algorithm. We stratified on Aβ1-42 pathology (Aβ+/−) and analyzed group differences, as well as associations with Framingham Risk Score for cardiovascular disease (FRS-CVD) and age. Occipital PWMH (p = 0.001) and occipital DWMH (p = 0.003) loads were increased in SCD-Aβ+ compared with Aβ− controls. In MCI-Aβ+ compared with Aβ− controls, there were differences in global WMH (p = 0.003), as well as occipital DWMH (p = 0.001) and temporal DWMH (p = 0.002) loads. FRS-CVD was associated with frontal PWMHs (p = 0.003) and frontal DWMHs (p = 0.005), after adjusting for age. There were associations between global and all regional WMH loads and age. In summary, posterior WMH loads were increased in SCD-Aβ+ and MCI-Aβ+ cases, whereas frontal WMHs were associated with vascular risk. The differences in WMH topography support the use of regional WMH load as an early-stage marker of etiology.  相似文献   
7.
Autosomal dominant leukodystrophy (ADLD) is an adult onset demyelinating disorder that is caused by duplications of the lamin B1 (LMNB1) gene. However, as only a few cases have been analyzed in detail, the mechanisms underlying LMNB1 duplications are unclear. We report the detailed molecular analysis of the largest collection of ADLD families studied, to date. We have identified the minimal duplicated region necessary for the disease, defined all the duplication junctions at the nucleotide level and identified the first inverted LMNB1 duplication. We have demonstrated that the duplications are not recurrent; patients with identical duplications share the same haplotype, likely inherited from a common founder and that the duplications originated from intrachromosomal events. The duplication junction sequences indicated that nonhomologous end joining or replication‐based mechanisms such fork stalling and template switching or microhomology‐mediated break induced repair are likely to be involved. LMNB1 expression was increased in patients’ fibroblasts both at mRNA and protein levels and the three LMNB1 alleles in ADLD patients show equal expression, suggesting that regulatory regions are maintained within the rearranged segment. These results have allowed us to elucidate duplication mechanisms and provide insights into allele‐specific LMNB1 expression levels.  相似文献   
8.
9.
A 52-year-old woman with Takayasu arteritis and a known history of multiple sclerosis had been treated with subcutaneous interferon (IFN) beta-1α. After the re-introduction of the IFN beta-1α, the patient had a gradual worsening of the arteritis, with claudication symptoms in the left arm and increased inflammation markers. An evaluation using Doppler ultrasound of the supra-aortic vessels revealed severe stenosis of the left axillary artery. The IFN beta-1α was withdrawn, with prompt clinical and laboratory improvement of the vasculitis.  相似文献   
10.

Background

The fields of surgery and trauma care have largely been neglected in the global health discussion. As a result the idea that surgery is not safe or cost effective in resource-limited settings has gone unchallenged. The SIGN Online Surgical Database (SOSD) is now one of the largest databases on trauma surgery in low- and middle-income countries (LMIC). We wished to examine infection rates and risk factors for infection after IM nail operations in LMIC using this data.

Methods

The SOSD contained 46,722 IM nail surgeries in 58 different LMIC; 46,113 IM nail operations were included for analysis.

Results

The overall follow-up rate was 23.1 %. The overall infection rate was 1.0 %, 0.7 % for humerus, 0.8 % for femur, and 1.5 % for tibia fractures. If only nails with registered follow-up (n = 10,684) were included in analyses, infection rates were 2.9 % for humerus, 3.2 % for femur, and 6.9 % for tibia fractures. Prophylactic antibiotics reduced the risk of infection by 29 %. Operations for non-union had a doubled risk of infection. Risk of infection was reduced with increasing income level of the country.

Conclusions

The overall infection rates were low, and well within acceptable levels, suggesting that it is safe to do IM nailing in low-income countries. The fact that operations for non-union have twice the risk of infection compared to primary fracture surgery further supports the use of IM nailing as the primary treatment for femur fractures in LMIC.  相似文献   
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