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91.

Objective

To assess the feasibility of measuring ventilatory threshold (VT) in higher-level motor-complete spinal cord injury (SCI) using 4 different analysis methods based on noninvasive gas exchange.

Design

Observational.

Setting

Laboratory testing.

Participants

Individuals with C4-T6 motor-complete SCI (16 paraplegia, 22 tetraplegia; American Spinal Injury Association Impairment Scale A/B; 42±10 years old).

Interventions

Not applicable.

Main Outcome

VT from a graded arm cycling test to volitional exhaustion using 4 methods: ventilatory equivalents, excess CO2, V-slope, and combined method.

Results

VT could be identified in all individuals with paraplegia, but in only 68% of individuals with tetraplegia. Individuals without observable VT completed the graded exercise test with lower ventilatory rate, peak power output, and peak oxygen consumption (Vo2peak) (all P<.05), compared to those with a detectable VT. Bland-Altman plots indicate minimal bias between methods (range: 0.01-0.03 L/min), with 95% limits of agreement of the difference within 0.25 L/min. Absolute V.o2 at VT with individual methods were all correlated to peak power output (r>0.74; P<.01) and Vo2peak (r>0.91; P<.01), with negligible differences between methods.

Conclusions

The assessment of VT is a feasible alternative to peak exercise testing for aerobic fitness in individuals with higher-level, motor-complete SCI, although care should be taken when interpreting VT in individuals with tetraplegia who have lower cardiorespiratory fitness and lower peak power outputs.  相似文献   
92.
Journal of Thrombosis and Thrombolysis - To study whether a diagnosis of cancer affects the clinical presentation and outcomes of patients with pulmonary embolism (PE). A retrospective analysis was...  相似文献   
93.
94.
OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
95.
Pulmonary nocardiosis re-visited: experience of 35 patients at diagnosis   总被引:1,自引:0,他引:1  
Pulmonary infection by Nocardia is an uncommon opportunistic infection in humans. Thirty-five patients with pulmonary nocardiosis were identified in two tertiary referral hospitals. A retrospective review of the patient characteristics, clinical and laboratory features including antimicrobial susceptibility at diagnosis was carried out. Radiological features derived from chest radiographs and CT scans were also documented. In our population, the predominant risk factors were immuno-compromised state, corticosteroid therapy, and underlying pulmonary pathology. The presenting features were similar to those previously described but disseminated infection was not common. The radiological changes were diverse and non-specific. Nocardia asteroides was the commonest species. Most Nocardia isolates were susceptible to imipenem, ceftriaxone, amikacin, and cotrimoxazole. Co-existing microbial agents are common and reflect the underlying complex disorders.  相似文献   
96.
A Chinese family with concurrent hereditary spherocytosis (HS) and haemoglobin (Hb) Q-Thailand is described. The Hb Q-Thailand mutation was found on the remaining alpha1 globin gene on a chromosome 16 containing the (-alpha 4.2) deletion. Active haemolysis in members of this family is segregated with the HS phenotype, and the Hb Q-Thailand in the heterozygous state does not seem to show any modulating effect on HS.  相似文献   
97.
Brief heating (43 C for 15 min) of the scrota of adult rats was used to induce reversible spermatogenic damage to the testes. In these animals the changes in testicular inhibin content and an index of inhibin production rate, measured after efferent duct ligation, were examined and correlated with serum gonadotropin levels. The effect of heating was not evident until after 1 week when testis weight, inhibin content, and inhibin production rate were significantly reduced and both serum FSH and LH were elevated. By 2 weeks, the maximal effects were observed, and, thereafter, all parameters gradually returned to control values (FSH: by 6 weeks; testis and epididymal weight, inhibin content, inhibin production rate, and seminiferous tubule fluid production: by 17 weeks). Throughout the study, serum testosterone levels showed no significant changes. Significant inverse correlations were found between serum FSH levels and inhibin content (r = -0.502, P less than 0.001) or inhibin production rate (r = -0.533, P less than 0.001), and these were taken as supportive evidence for the hypothesis that inhibin is involved in the feedback control of pituitary FSH secretion. Although serum LH levels were also negatively correlated to the corresponding inhibin content (r = -0.669, P less than 0.001) or inhibin production rate (r = -0.420, P less than 0.001), recent findings of Leydig cell dysfunction in these animals led us to relate the transient rise in LH to the altered state of Leydig cell function.  相似文献   
98.
The recognition of cancer cells by T cells can impact upon prognosis and be exploited for immunotherapeutic approaches. This recognition depends on the specific interaction between antigens displayed on the surface of cancer cells and the T cell receptor (TCR), which is generated by somatic rearrangements of TCR α‐ and β‐chains (TCRb). Our aim was to assess whether ultra‐deep sequencing of the rearranged TCRb in DNA extracted from unfractionated clear cell renal cell carcinoma (ccRCC) samples can provide insights into the clonality and heterogeneity of intratumoural T cells in ccRCCs, a tumour type that can display extensive genetic intratumour heterogeneity (ITH). For this purpose, DNA was extracted from two to four tumour regions from each of four primary ccRCCs and was analysed by ultra‐deep TCR sequencing. In parallel, tumour infiltration by CD4, CD8 and Foxp3 regulatory T cells was evaluated by immunohistochemistry and correlated with TCR‐sequencing data. A polyclonal T cell repertoire with 367–16 289 (median 2394) unique TCRb sequences was identified per tumour region. The frequencies of the 100 most abundant T cell clones/tumour were poorly correlated between most regions (Pearson correlation coefficient, –0.218 to 0.465). 3–93% of these T cell clones were not detectable across all regions. Thus, the clonal composition of T cell populations can be heterogeneous across different regions of the same ccRCC. T cell ITH was higher in tumours pretreated with an mTOR inhibitor, which could suggest that therapy can influence adaptive tumour immunity. These data show that ultra‐deep TCR‐sequencing technology can be applied directly to DNA extracted from unfractionated tumour samples, allowing novel insights into the clonality of T cell populations in cancers. These were polyclonal and displayed ITH in ccRCC. TCRb sequencing may shed light on mechanisms of cancer immunity and the efficacy of immunotherapy approaches. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
99.

Although extracurricular music activities are common in Hong Kong, private music teachers’ perceptions of children with autism spectrum disorder (ASD) are underexplored in research in this context. This study examined private music teachers’ knowledge of ASD and their attitudes toward students with ASD in Hong Kong, and the relationship between these two factors. The study collected data from a questionnaire survey (n?=?200) and eleven individual interviews. Unexpectedly, the findings showed that the teachers had a good understanding and a marginally positive perception of ASD, despite some anxiety about teaching students with ASD. Furthermore, knowledge of and attitude toward ASD were positively correlated. Teachers with previous training in special education needs had a better understanding of ASD and a more positive attitude toward ASD than those without related training. These results imply that further formal and public education could promote acceptance of and equal learning opportunities for students with ASD.

  相似文献   
100.
ObjectiveSocial isolation and loneliness are associated with morbidity and mortality in older adults. Limited evidence exists regarding which interventions improve connectedness in this population.Design/Setting/ParticipantsIn this pre-post study we assessed community-based group health class participants’ (age ≥50) loneliness and social isolation. Participants (n = 382) were referred by a Cedars-Sinai Medical Network (Los Angeles, California) healthcare provider or self-referred from the community (July 2017–March 2020).InterventionParticipants met with a program coordinator and selected Arthritis Exercise, Tai Chi for Arthritis, EnhanceFitness, or the Healthier Living Workshop.MeasurementsWe measured social isolation using the Duke Social Support Index (DSSI) and loneliness using the UCLA 3-item Loneliness Scale at baseline, class completion, and 6 months.ResultsMean age was 76.8 years (standard deviation, SD = 9.1); 315 (83.1%) were female; 173 (45.9%) were Non-Hispanic white; 143 (37.9%) were Non-Hispanic Black; 173 (46.1%) lived alone; mean baseline DSSI score was 26.9 (SD = 4.0) and mean baseline UCLA score was 4.8 (SD = 1.8). On multivariable analysis adjusted for gender, race/ethnicity, income, self-rated health, and household size, DSSI improved by 2.4% at 6-week compared to baseline (estimated ratio, ER: 1.024; 95% confidence interval [CI]: 1.010–1.038; p-value = 0.001), and 3.3% at 6-month (ER: 1.033; 95% CI: 1.016–1.050; p-value <0.001). UCLA score after adjusting for age, gender, race/ethnicity, live alone, number of chronic conditions, income, and self-rated health, did not change at 6-week (ER: 0.994; 95% CI: 0.962–1.027; p-value = 0.713), but decreased by 6.9% at 6-months (ER: 0.931; 95% CI: 0.895–0.968; p-value <0.001).ConclusionCommunity-based group health class participants reported decreased loneliness and social isolation at 6-month follow-up.  相似文献   
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