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971.
ABSTRACT: BACKGROUND: Muscle injuries are one of the commonest injuries affecting athletes. It often leads to significant pain and disability causing loss of training and competition time. With current treatment, the duration to return-to-play ranges form six weeks to never, depending on injury severity. Recent researches have suggested that autologous platelet-rich plasma (PRP) injection into the injured site may hasten soft tissues healing. To-date, there has been no randomised clinical trials to evaluate the effects of PRP on muscle healing. The aim of this study is to examine the effects of autologous PRP on duration to return-to-play after muscle injury. Methods and design A randomised, single blind controlled trial will be conducted. Twenty-eight patients aged 18 years and above with a recent grade-2 hamstring injury will be invited to take part. Participants will be randomised to receive either autologous PRP injection with rehabilitation programme, or rehabilitation programme only. Participants will be followed up at day three of study and then weekly for 16 weeks. At each follow up visit, participants will be assessed on readiness to return-to-play using a set of criteria. The primary end-point is when participants have fulfilled the return-to-play criteria or end of 16 weeks. The main outcome measure of this study is the duration to return-to-play after injury. CONCLUSION: This study protocol proposes a rigorous and potential significant evaluation of PRP use for grade-2 hamstring injury. If proven effective such findings could be of great benefit for patients with similar injuries. Trial registration Current Controlled Trials ISCRTN66528592. 相似文献
972.
973.
974.
Maheswari Ekambaram Matilde Irigoyen Johelin DeFreitas Sharina Rajbhandari Jessica Lynn Geaney Leonard Edward Braitman 《World journal of pediatrics : WJP》2018,14(4):357-363
Background
In adolescents, there is limited evidence on the independent and additive effect of prepregnancy body mass index (BMI) and gestational weight gain on infant birth weight. Data also show that this effect may vary by race. We sought to examine the impact of maternal prepregnancy BMI and gestational weight gain on birth weight and risk of large for gestational age (LGA) in term newborns of minority adolescent mothers.Methods
This was a retrospective cohort study of 411 singleton live term infants born to mothers ≤ 18 years. Data were abstracted from electronic medical records.Results
Gestational weight gain was related to infant birth weight (ρ = 0.36, P < 0.0001), but BMI was not (ρ = 0.025, P = 0.61). On regression analysis, gestational weight gain, gestational age and Hispanic ethnicity were independent predictors of birth weight, controlling for maternal age, BMI, parity, tobacco/drug use and preeclampsia. The probability of having an LGA infant increased with weight gain [adjusted odds ratio (aOR) 1.14, 95% confidence interval (CI) 1.07–1.21] but not with BMI. Mothers who gained weight in excess of 2009 Institute of Medicine (IOM) recommendations had a greater risk of having an LGA infant compared to those who gained within recommendations (aOR 5.7, 95% CI 1.6–19.5).Conclusions
Minority adolescents with greater gestational weight gain had infants with higher birth weight and greater risk of LGA; BMI was not associated with either outcome. Further studies are needed to examine the applicability of the 2009 BMI-specific IOM gestational weight gain recommendations to adolescents in minority populations.975.
Natasha Najwa Nor Arfuzir Renu Agarwal Igor Iezhitsa Puneet Agarwal Sabrilhakim Sidek Nafeeza Mohd Ismail 《中国神经再生研究》2018,(11)
Endothelin-1(ET-1), a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine(TAU), a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co-or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress. 相似文献
976.
Martin MY Person SD Kratt P Prayor-Patterson H Kim Y Salas M Pisu M 《Patient education and counseling》2008,72(1):137-145
OBJECTIVE: While self-efficacy plays an important role in physical activity, relatively little research has examined this construct in minorities. This study identified theoretical correlates associated with self-efficacy among insufficiently active, hypertensive Black women. METHODS: Correlates of self-efficacy to: (1) overcoming barriers to physical activity; (2) making time for activity; and (3) "sticking with" physical activity were studied. RESULTS: Sixty-one women (M=50.48+/-4.2 years) participated. We accounted for 32% of the variance in confidence in overcoming barriers. Women confident in overcoming barriers reported less worry about physical activity. The TTM processes of change were also in the model: consciousness raising, environmental reevaluation, counter conditioning, and self-liberation. We accounted for 16% of the variance in "making time" self-efficacy. An aversiveness barrier (e.g., physical activity is boring, physical activity is hard work) was the dominant variable in the model. Confidence to 'stick with' physical activity was associated with self-reevaluation (i.e., reflection on how personal values correspond to behavior). Social support and competing demands were not associated with self-efficacy. CONCLUSIONS: Consistent with Social Cognitive Theory, results suggest that self-efficacy is behavior specific and each measure likely provides unique information. PRACTICE IMPLICATIONS: Interventions should be tailored to address specific self-efficacy types. 相似文献
977.
Yusof MM Kuljis J Papazafeiropoulou A Stergioulas LK 《International journal of medical informatics》2008,77(6):386-398
BACKGROUND AND PURPOSE: The realization of Health Information Systems (HIS) requires rigorous evaluation that addresses technology, human and organization issues. Our review indicates that current evaluation methods evaluate different aspects of HIS and they can be improved upon. A new evaluation framework, human, organization and technology-fit (HOT-fit) was developed after having conducted a critical appraisal of the findings of existing HIS evaluation studies. HOT-fit builds on previous models of IS evaluation--in particular, the IS Success Model and the IT-Organization Fit Model. This paper introduces the new framework for HIS evaluation that incorporates comprehensive dimensions and measures of HIS and provides a technological, human and organizational fit. METHODS: Literature review on HIS and IS evaluation studies and pilot testing of developed framework. The framework was used to evaluate a Fundus Imaging System (FIS) of a primary care organization in the UK. The case study was conducted through observation, interview and document analysis. RESULTS: The main findings show that having the right user attitude and skills base together with good leadership, IT-friendly environment and good communication can have positive influence on the system adoption. CONCLUSIONS: Comprehensive, specific evaluation factors, dimensions and measures in the new framework (HOT-fit) are applicable in HIS evaluation. The use of such a framework is argued to be useful not only for comprehensive evaluation of the particular FIS system under investigation, but potentially also for any Health Information System in general. 相似文献
978.
Huda Mohammed Sabbar Zulkiflle Leman Shazarel Shamsudin Suraya Mohd Tahir Che Nor Aiza Jaafar Azmah Hanim Mohamed Ariff Nur Ismarrubie Zahari Mohammed H. Rady 《Materials》2021,14(21)
Direct solid-states, such as hot extrusion and equal channel angular pressing (ECAP), are alternative and efficient solid-state processes for use in recycling aluminium scrap. These processes utilise less energy and are eco-friendly. Ceramic particles such as ZrO2 are suggested as alternatives in the production of metal composites. This study investigated and optimised the effects of various parameters of reinforced ZrO2 nanoparticles on the mechanical and physical properties via response surface methodology (RSM). These parameters were the volume fraction (VF), preheating temperature (T), and preheating time (t). The effects of these parameters were examined before and after the heat treatment condition and ECAP. Each parameter was evaluated at varying magnitudes, i.e., 450, 500, and 550 °C for T, 1, 2, and 3 h for t, and 1, 3, and 5% for VF. The effect that process variables had on responses was elucidated using the factorial design with centre point analysis. T and VF were crucial for attaining the optimum ultimate tensile strength (UTS) and microhardness. Reducing VF increased the mechanical properties to 1 vol% of oxide. The maximum hardness of 95 HV was attained at 550 °C, 1.6 h, and 1 vol% ZrO2 with a density of 2.85 g/cm3 and tensile strength of 487 MPa. UTS, density, and microhardness were enhanced by 14%, 1%, and 9.5%, respectively. Additionally, the hot extrusion parameters and ECAP followed by heat treatment strengthened the microhardness by 64% and density by 3%. Compression pressure and extrusion stress produced in these stages were sufficient to eliminate voids that increased the mechanical properties. 相似文献
979.
Intraoperative Ultrasound with Palpation is Still Superior to Intra-arterial Calcium Stimulation Test in Localising Insulinoma 总被引:1,自引:0,他引:1
Aim This study assessed the sensitivities of preoperative localisation modalities such as computed tomography (CT), magnetic resonance
imaging (MRI), arteriography and arterial stimulation venous sampling (ASVS) using serum insulin and C-peptide gradients to
intraoperative techniques in localising insulin-secreting tumours in our institution.
Methods Fourteen patients with proven insulinoma, aged 20–66 years, who presented from 1997 to 2004, were studied retrospectively.
All patients underwent ASVS where C-peptide and/or insulin gradients were calculated. The results were compared with the preoperative
findings of CT, MRI, arteriography, as well as intraoperative ultrasound and palpation.
Results Intraoperative ultrasound with palpation correctly localised 10 of the 11 tumours with a sensitivity of 91%. Sensitivities
of other localisation techniques were lower: 31% by CT, 50% by MRI, and 46% by arteriography. ASVS with insulin gradients
alone allowed accurate localisation in 40% of patients while localisation using only C-peptide gradients of more than 2 was
43%. The insulinomas, measuring 10–30 mm, were successfully removed in 13 patients—6 from the body, 4 from the tail, 2 from
the head and 1 from the junction of the body and tail. All except 1 were cured by selective surgery and remained free of hypoglycaemia
over the next 2–60 months of follow-up. One patient had left lobectomy due to liver metastases from a malignant insulinoma
and remained asymptomatic with medical therapy.
Conclusions Intraoperative ultrasound with palpation is a highly sensitive method for the localisation of insulinoma compared with other
preoperative localisation techniques. 相似文献
980.
Abd Rashid Nur Haslindawaty Sundararajulu Panneerchelvam Hisham Atan Edinur Mohd Nor Norazmi Zainuddin Zafarina 《International journal of legal medicine》2010,124(5):415-426
The uniparentally inherited mitochondrial DNA (mtDNA) is in the limelight for the past two decades, in studies relating to
demographic history of mankind and in forensic kinship testing. In this study, human mtDNA hypervariable segments 1, 2, and
3 (HV1, HV2, and HV3) were analyzed in 248 unrelated Malay individuals in Peninsular Malaysia. Combined analyses of HV1, HV2,
and HV3 revealed a total of 180 mtDNA haplotypes with 149 unique haplotypes and 31 haplotypes occurring in more than one individual.
The genetic diversity was estimated to be 99.47%, and the probability of any two individuals sharing the same mtDNA haplotype
was 0.93%. The most frequent mtDNA haplotype (73, 146, 150, 195, 263, 315.1C, 16140, 16182C, 16183C, 16189, 16217, 16274,
and 16335) was shared by 11 (4.44%) individuals. The nucleotide diversity and mean of pair-wise differences were found to
be 0.036063 ± 0.020101 and 12.544022 ± 6.230486, respectively. 相似文献