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81.
This paper reports the construction of gross motor development curves for children and youth with cerebral palsy (CP) in order to assess whether function is lost during adolescence. We followed children previously enrolled in a prospective longitudinal cohort study for an additional 4 years, as they entered adolescence and young adulthood. The resulting longitudinal dataset comprised 3455 observations of 657 children with CP (369 males, 288 females), assessed up to 10 times, at ages ranging from 16 months to 21 years. Motor function was assessed using the 66-item Gross Motor Function Measure (GMFM-66). Participants were classified using the Gross Motor Function Classification System (GMFCS). We assessed the loss of function in adolescence by contrasting a model of function that assumes no loss with a model that allows for a peak and subsequent decline. We found no evidence of functional decline, on average, for children in GMFCS Levels I and II. However, in Levels III, IV, and V, average GMFM-66 was estimated to peak at ages 7 years 11 months, 6 years 11 months, and 6 years 11 months respectively, before declining by 4.7, 7.8, and 6.4 GMFM-66 points, in Levels III, IV, and V respectively, as these adolescents became young adults. We show that these declines are clinically significant.  相似文献   
82.
Background:  Caudal extradural blockade is one of the most commonly performed procedures in pediatric anesthesia. However, there is little information available on variations in clinical practice.
Objectives:  To perform a survey of members of the Association of Paediatric Anaesthetists of Great Britain and Ireland who undertake caudal anesthesia.
Methods:  An 'online' World Wide Web questionnaire collected information on various aspects of clinical practice. The survey ran from April to June 2008.
Results:  There were 366 questionnaires completed. The majority of respondents had >5 years of pediatric experience and performed up to ten caudal extradural procedures a month. The commonest device used was a cannula (69.7%) with 68.6% using a 22G device. There was a trend toward the use of a cannula in those anesthetists with <15 years experience, while those with >15 years experience tended to use a needle. Most anesthetists (91.5%) did not believe that there was a significant risk of implantation of dermoid tissue into the caudal extradural space. The majority used a combination of clinical methods to confirm correct placement. Only 27 respondents used ultrasound. The most popular local anesthetics were bupivacaine (43.4%) and levobupivacaine (41.7%). The most common additives were clonidine (42.3%) and ketamine (37.5%). The caudal catheter technique was used by 43.6%. Most anesthetists (74%) wear gloves for a single shot caudal injection.
Conclusions:  This survey provides a snapshot of current practice and acts a useful reference for the development of enhanced techniques and new equipment in the future.  相似文献   
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84.
Coagulation involves the regulated sequence of proteolytic activation of a series of zymogens to achieve appropriate and timely haemostasis in an injured vessel, in an environment that overwhelmingly favours an anticoagulant state. In the non-pathological state, the inciting event involves exposure of circulating factor VII/VIIa to extravascularly expressed tissue factor, which brings into motion the series of steps which results in amplification of the initial stimulus, culminating in the conversion of fibrinogen to fibrin and clot formation. The precisely synchronized cascade of events is counter-balanced by a system of anticoagulant mechanisms, which serve to ensure that the haemostatic effect is regulated and does not extend inappropriately. Conversely, in pathological states, these events can escape normal control mechanisms, due to either inherited or acquired defects, which lead to thrombosis. Current anticoagulant therapy, although based on medications that have been in existence for upwards of 80 years, is moving towards targeted therapy for specific coagulation factors and events in the coagulation cascade, based on the current knowledge of the main triggers and key events within the series of reactions that culminates in haemostasis. It remains to be seen whether these newer medications will become first-line therapies for thrombosis in the coming decade. This review aims to elucidate the main events within the coagulation cascade as it is currently understood to operate in vivo , with a brief discussion focusing on hypercoagulable states, and also a short review of the history of anticoagulants as they relate to this model.  相似文献   
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86.
A patient with sickle cell trait and nutritional megaloblastic anemia wasfound to have a much smaller proportion of hemoglobin S during the megaloblastic phase than after recovery. This observation suggests preferential synthesis of hemoglobin A by megaloblastic bone marrow in the presence of theA-S trait.

Submitted on July 30, 1962 Accepted on November 9, 1962  相似文献   
87.
It is demonstrated that anemia per se can have a marked influence on theabsorption of iron that is independent of the effects of alterations in the rateof erythropoiesis and the body iron content.

Evidence is presented which suggests that the effects of anemia, the rate oferythropoiesis and the body iron content on the absorptive mechanism foriron are, to some extent, additive.

Submitted on March 6, 1963 Accepted on May 27, 1963  相似文献   
88.
The dependence of the 13C shift difference of proline carbons Cβ and Cγ on the dihedral angle ø has been studied using the model peptide acetyl-d -proline N-methylamide. The shift difference Δβγ is shown to be correlated with the percent cis isomer about the acetylproline bond, both factors depending strongly on the degree of intermolecular hydrogen bonding. Both the fraction of trans peptide bond and the fractional γ-turn conformation increase as the sample concentration is decreased in CDCl3. Δβγ values have been used to evaluate the fractional γ-turn probabilities in a number of cyclic and linear peptides including thyrotropin releasing factor and bradykinin. Using this parameter, it is concluded that in bradykinin the γ-turn probability is low in D2O and not strongly temperature dependent. In contrast, studies of a model peptide for the portion of bradykinin believed to adopt a γ-turn conformation are consistent with an increased γ-turn probability in less polar solvents. Data for X-Pro-Y peptides (Y = imino acid) indicate significantly reduced values of Δβγ, and this appears to be a useful basis for assigning the Pro Cβ resonances corresponding to this sequence.  相似文献   
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