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71.
Parallel increases in strength and rate of force development (RFD) are well-known outcomes from the initial phase of resistance training. However, it is unknown whether neural adaptations with training contribute to improvements of both factors. The aim of this study was to examine whether changes in H-reflex amplitude with resistance training can explain the gain in strength or rather be associated with RFD. Twelve subjects carried out 3 weeks of isometric maximal plantarflexion training, whereas 12 subjects functioned as contr ols. H-reflexes were elicited in the soleus muscle during rest and sub-maximal contractions at 20 and 60% of maximal voluntary contraction (MVC). In addition, surface electromyography (sEMG) was recorded from the soleus, gastrocnemius and tibialis anterior muscles during MVC. The resistance training provided increases in maximal force of 18%, RFD of 28% and H-reflex amplitude during voluntary contractions of 17 and 15% while no changes occurred in the control group. In contrast, the maximal M-wave, the maximal H-reflex to maximal M-wave ratio during rest and sEMG during MVC did not change with training. There was a positive correlation between percentage changes in H-reflex amplitude and RFD with training (r = 0.59), while significant association between percentage changes in H-reflex amplitude and maximal force was not found. These findings indicate the occurrence of changed motoneuron excitability or presynaptic inhibition during the initial phase of resistance training. This is the first study to document that increased RFD with resistance training is associated with changes in reflex excitability.  相似文献   
72.
We recently identified 2 Mokola viruses from domestic mammals (a dog and a cat) in South Africa. These cases occurred 8 years after the last reported case of infection with this virus. Our findings emphasize the endemicity of rabies-related lyssaviruses in South Africa and the need to better understand the epidemiology of Mokola viruses.  相似文献   
73.
OBJECTIVES: Several studies have shown that exposure to antineoplastic drugs can cause toxic effects on reproductive health as well as carcinogenic effects. Numerous studies have corroborated that hospital workers are exposed to these drugs. This study focused on trends in exposure to antineoplastic drugs since the introduction of guidelines in The Netherlands. METHODS: Data from three cross-sectional exposure surveys conducted in The Netherlands were pooled to examine trends in occupational exposure to cyclophosphamide. Nurses' 24 h urine samples were analyzed in separate fractions, surface contamination was determined and gloves used during preparation or while handling patient urine were collected. The difference in detectable urine samples between 1997 and 2000 was determined by a generalized estimating equations (GEE) binomial regression model. Mixed models were used to study the time trend in surface and glove contamination levels. RESULTS: The percentage of nurses' urine samples with detectable cyclophosphamide had decreased 4-fold between 1997 and 2000. Median cyclophosphamide levels in the positive urine samples were 3-fold lower in 2000 than in 1997. Surface and glove contamination had statistically significantly decreased between 1997 and more recent years. CONCLUSIONS: Nurses working at outpatient clinics or oncology wards are still being exposed to cyclophosphamide, but their exposure decreased considerably between 1997 and 2000, presumably due to the introduction of detailed guidelines and regulations in The Netherlands, the subsequent increased use of LuerLock connections and infusion systems prefilled with saline, and growing hazard awareness of nurses working with antineoplastic drugs.  相似文献   
74.
Weyer J  Rupprecht CE  Mans J  Viljoen GJ  Nel LH 《Vaccine》2007,25(21):4213-4222
Modified vaccinia virus Ankara (MVA) has become a vaccine vector of choice for recombinant vaccine development. A MVA-based rabies vaccine would be advantageous for use as a vaccine for dogs (and wildlife), particularly if it proves innocuous and efficacious by the oral route. Here, the generation and immunological testing of a recombinant MVA expressing a rabies virus glycoprotein gene is described. In a murine model, higher dosages of recombinant MVA were needed to induce equivocal immune responses as with Vaccinia Copenhagen or Vaccinia Western Reserve recombinants, when administered by a parenteral route. The MVA recombinant was not immunogenic or efficacious when administered per os in na?ve mice. The ability of the recombinant MVA to induce anamnestic responses in dogs and raccoons was also investigated. Recombinant MVA boosted humoral immune responses in these animals when administered peripherally, but not when administered orally.  相似文献   
75.
76.
Patients presenting in major tuberculosis (TB) centres in two Australian metropolitan hospitals and three central hospitals in Malawi were interviewed for health and other information, including their satisfaction with nursing care. The main objective of the study was to investigate differences in satisfaction rates among ethnically similar and different patients coming from two dissimilar health systems. A multivariable Generalized Estimating Equations model was constructed to identify sociodemographic and health‐related factors associated with dissatisfaction, while focusing on ethnic differences between and within each country. The Australian and Malawian patients were similar in age, gender, marital status, and employment. However, the Malawians were mostly inpatients, with recurrent TB episodes, and were more seriously ill with impaired physical and mental wellbeing. Nonetheless, being Australian was more associated with dissatisfaction observed in all components of care. However, Australian ethnic minorities were less dissatisfied than their Anglo‐Saxon or European counterparts, being more similar to Malawian patients irrespective of the health care provided. Our study suggests that patients coming from similar ethnic backgrounds may express similar satisfaction irrespective of the health system they belong to.  相似文献   
77.
Sepsis in pregnancy and the puerperium remains a significant cause of maternal mortality and morbidity worldwide. Major morbidity arising as a result of obstetric sepsis includes fetal demise, organ failure, chronic pelvic inflammatory disease, chronic pelvic pain, bilateral tubal occlusion and infertility. Early recognition and timely response are key to ensuring good outcome. This review examines the clinical problem of sepsis in obstetrics and the role of the anaesthetist in the management of this condition.  相似文献   
78.
Purpose: Causes of low vision in the Netherlands may have changed over time. The purpose of this study is to assess trends over the last two decades. Methods: Socio‐demographic and medical data, including ophthalmic diagnosis and inheritance patterns for 2843 children with low vision (0–21 years; 50% representation) referred to a Dutch institute for low vision (Bartiméus) over a 21‐year period between 1988 and 2009, were included in the analysis. For the 19 most common diagnoses, inheritance and presence of mental impairment, trend analyses were performed with logistic regression models; odds ratios (OR) for a 10‐year time span were reported. Results: Cerebral visual impairment (CVI) was found in 27.2% (97% mental impairment), albinism in 8.0%. Over time, nystagmus (6.6%; OR = 1.42), retinitis pigmentosa (2.9%; OR = 1.61), cone‐rod dystrophy (2.6%; OR = 1.98) and hyperopia (2.0%; OR = 3.66) increased significantly. Cataract (4.9%; OR = 0.64), aniridia (1.6%; OR = 0.42) and retinopathy of prematurity (ROP; 2.0%; OR = 0.45) decreased significantly. There was a significant increase in genetic disorders (41.0%; OR = 1.49) and in co‐occurrence of mental impairment (52.2% OR = 1.16). Conclusion: In the last two decades, treatable or preventable disorders (such as cataract and ROP) have become a less common cause of low vision in children. However, the prevalence of complex (genetic) and untreatable disorders (CVI) has taken its place, as a result of increased survival of preterm and low birth weight children and improved diagnostic possibilities. Knowledge of the prevalence of low vision, its causes and trends over time may help policy makers to define effective intervention strategies and to monitor its impact.  相似文献   
79.
It is well established that nursing practice produces considerable anxiety, and it can also give rise to envy and jealousy. While envy in nursing was identified in the literature more than 50 years ago, there remains a paucity of articles addressing either envy or jealousy for nurses. In a recent research study on current experiences of clinical practice, we analysed a fragment of nurses’ speech via Klein's theory of jealousy. The results revealed that the nurses expressed jealousy at the privilege afforded to doctors. We argue that it is important to acknowledge jealousy in nursing practice because it has the potential for ‘spoiling’ effective care delivery and as such, can have detrimental ramifications in the health system. Also, jealousy may keep the nurse from fully focusing on their nursing practice in that it divides the nurse's attention and so limits the nurse's treatment of the patient. Nurses’ jealousy of doctors is a taboo topic in nursing, and yet it warrants serious consideration due to the potential deleterious consequences that can arise when this dynamic is present.  相似文献   
80.
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