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排序方式: 共有1002条查询结果,搜索用时 31 毫秒
1.
Richard J Levy Whitney B Stern Kimberly I Minger Lisa M Montenegro Chitra Ravishankar Jonathan J Rome Susan C Nicolson David R Jobes 《Pediatric critical care medicine》2005,6(6):671-675
BACKGROUND: Mixed venous saturation (S & OV0456;o2) is an important measurement that helps guide the care of critically ill patients. Invasive S & OV0456;o2 assessment in infants and children is often avoided because of the inherent risks. A noninvasive tissue saturation (S to 2) monitor has recently been developed that uses near-infrared spectroscopy to measure oxyhemoglobin saturation in muscle. In adult and animal studies, S to 2 correlated with oxygen delivery and S & OV0456;o2. There has been no evaluation in pediatric patients. OBJECTIVE: To evaluate tissue saturation as a noninvasive measure of mixed venous saturation in children. DESIGN: A prospective observational study. SETTING: Catheterization laboratory in a tertiary care children's medical center. PATIENTS: We studied 98 children (49 without intracardiac mixing and 49 with intracardiac mixing) 相似文献
2.
Central nervous system myelin is elaborated by oligodendrocytes, which have been studied extensively in cell culture. Dissociated brain cultures allow in vitro analysis of events in myelinogenesis, including cell-cell interactions. Microglia, the primary phagocytic cell of the central nervous system, appear in developing fiber tracts prior to the onset of myelination in vivo. To gain insight into potential oligodendrocytemicroglial interactions during development, these cells were co-cultured and various parameters of myelin synthesis were measured. In co-culture, microglia stimulated the synthesis of sulfatide, a myelin-specific galactolipid, in oligodendrocytes, as well as the expression of the myelin-specific proteins myelin basic protein and proteolipid protein. Activity of the oligodendrocyte cytoplasm-specific enzyme 2′,3′-cyclic nucleotide 3′-phosphohydrolase was not elevated, suggesting that the effects of microglia were not due to stimulation of oligodendrocyte proliferation. This was confirmed by the inability of microglia to induce significant DNA synthesis. Conditioned medium from cultured microglia provided a similar stimulatory activity, suggesting that the increase in myelin synthesis does not require contact between oligodendrocytes and microglia. These findings suggest a stimulatory role for microglia during myelinogenesis. © 1994 Wiley-Liss, Inc. 相似文献
3.
4.
Joseph McDonnell Angelique J Goverde Frans F H Rutten Jan P W Vermeiden 《Human reproduction (Oxford, England)》2002,17(1):103-106
BACKGROUND: Estimating the probability of pregnancy leading to delivery and the influence of clinical factors on that probability is of fundamental importance in the treatment counselling of infertile couples. A variety of statistical techniques have been used to analyse fertility data, many borrowed from survival analysis. METHODS AND RESULTS: We propose an alternative method of analysis which is based on a discrete time Markov chain approach, with states 'pregnancy (leading to a delivery)', 'not pregnant', and 'censored' and in which the transition probabilities are dependent both on the clinical characteristics of the patient and the treatment given. CONCLUSIONS: We believe that the method of analysis presented here may be preferable to standard analyses in that it better reflects the clinical situation, it is a truly discrete time analysis applied to a discrete time situation, it explicitly models the censoring process (a process which in itself provides information of interest to the physician) and can be readily extended to a variety of clinical situations. 相似文献
5.
Quantitative analysis of muscle fibre type and myosin heavy chain Distribution in the frog hindlimb: implications for locomotory design 总被引:2,自引:0,他引:2
Lutz Gordon J. Bremner Shannon Lajevardi Nahal Lieber Richard L. Rome Lawrence C. 《Journal of muscle research and cell motility》1998,19(7):717-731
To investigate the design of the frog muscular system for jumping, fibre type distribution and myosin heavy chain (MHC) isoform composition were quantified in the hindlimb muscles of Rana pipiens. Muscles were divided into two groups: five large extensor muscles which were predicted to shorten and produce mechanical power during jumping (JP), and four much smaller muscles commonly used in muscle physiology studies, but that do not shorten or produce power during jumping (NJP). Fibres were classified as one of four different types (type 1, 2, 3 or tonic) or an intermediate type (type 1–2) based ontheir relative myosin-ATPase reactivity and MHC immunoreactivity in muscle cross-sections according to previous nomenclature established for amphibian skeletal muscle. Type 1 fibres correspond to the fastest and most powerful of the twitch fibres, and type 3 fibres are the slowest and least powerful. Myosin-ATPase histochemistry revealed that the JP muscles were co mposed primarily of type 1 fibres (89%) with a small percentage of type 2 (7%) and intermediate type 1–2 fibres (4%). The fibre type composition of NJP muscles was more evenly distributed between type 1 (29%), type 2 (46%) and type 1–2 (24%) fibres. Tonic fibres comprised less than 2% of the muscle cross-section in both JP and NJP groups. Similarly, MHC composition determined by quantitative SDS–PAGE revealed that JP muscles were composed predominantly of type 1 MHC (86%), with a balance of type 2 MHC (14%). The opposite pattern was found for MHC composition in the NJP muscles: type 1 (28%), type 2 (66%) and type 3 (6%). These results demonstrate that the large extensor muscles that produce the power required for jumping have a fibre type distribution that enables them to generate high levels of mechanical power, with the type 1 isoform accounting for 85–90% of the total M HC content. 相似文献
6.
Jan Höltge Linda Theron Richard G. Cowden Kaymarlin Govender Sally I. Maximo Jennifer S. Carranza Bhumika Kapoor Aakanksha Tomar Angelique van Rensburg Shuang Lu Hongwei Hu Valeria Cavioni Alessia Agliati Ilaria Grazzani Yoel Smedema Gunjanpreet Kaur Kingsley G. Hurlington Jackie Sanders Michael Ungar 《The Journal of adolescent health》2021,68(3):580-588
PurposeIn situations of adversity, young people draw on individual, relational, and contextual (community and cultural) resources to foster their resilience. Recent literature defines resilience as a capacity that is underpinned by a network of interrelated resources. Although empirical studies show evidence of the value of a network approach, little is known regarding how different country contexts influence which resources are most critical within a resource network and how resources interact for adolescent resilience.MethodsNetwork analysis was conducted with data from studies that had used the Child and Youth Resilience Measure. Regularized partial correlation networks of 17 resources were estimated for 14 countries (Botswana, Canada, China, Colombia, Equatorial Guinea, India, Indonesia, Italy, Jordan, New Zealand, the Philippines, Romania, South Africa, and Syrian refugees living in Jordan). The sample size was 18,914 (mean age = 15.70 years, 48.8% female).ResultsWe observed mostly positive associations between the resources of interest. The salience and strength of associations between resources varied by country. The most central resource across countries was having supportive caregivers during stressful times because this resource had the most and strongest positive associations with other resources.ConclusionsThis study gives first empirical evidence from multiple countries that an interplay of social–ecological resources (such as individual skills, peer, caregiver and community support, and educational aspirations and opportunities) matter for adolescent resilience. Across countries, caregiver support appears to be most central for adolescent resilience. Future resilience interventions might apply this network approach to identify important, contextually relevant resources that likely foster additional resources. 相似文献
7.
Eva M. Hoefnagels Lucas Weerheijm Angelique GM Witteveen Jan-Willem K Louwerens Noel Keijsers 《Foot and Ankle Surgery》2021,27(5):543-549
BackgroundThe aetiology of chronic therapy resistant plantar fasciitis (CTRPF) is multifactorial with more focus in recent times on the gastroc-soleus complex. This study evaluates the effect of lengthening the gastrocnemius muscle in CTRPF.MethodsAll patients with CRTPF complaints for at least one year underwent the same standard conservative treatment prior to surgery. 32 patients failed this treatment and underwent gastrocnemius recession. Silfverskiöld test, questionnaires and plantar pressure measurements were obtained at 5 visits.ResultsOne year follow up showed a significantly increase in dorsiflexion of the ankle (16 degrees), a decrease in VAS; 78 (SD: 19) to 20 (SD: 24) and significant improved functional scores. Plantar pressure measurements showed an increase of pressure under the medial proximal part of the midfoot and the 1 st metatarsal and a decrease under the hallux.ConclusionsA gastrocnemius recession results in a significant gain in dorsiflexion, altered loading of the foot and good clinical outcome in patients with CTRPF.Level of EvidenceLevel 2 相似文献
8.
Mouillet Guillaume Falcoz Antoine Fritzsch Joëlle Almotlak Hamadi Jacoulet Pascale Pivot Xavier Villanueva Cristian Mansi Laura Kim Stefano Curtit Elsa Meneveau Nathalie Adotevi Olivier Jary Marine Eberst Guillaume Vienot Angelique Calcagno Fabien Pozet Astrid Djoumakh Oumelkheir Borg Christophe Westeel Virginie Anota Amélie Paget-Bailly Sophie 《Quality of life research》2021,30(11):3255-3266
Quality of Life Research - Routine Electronic Monitoring of Health-Related Quality of Life (HRQoL) (REMOQOL) in clinical care with real-time feedback to physicians could help to enhance... 相似文献
9.
Arend Mosaterd Jaap W. Deckers Arno W. Hoes Angelique Nederpel Albert Smeets David T. Linker Diederick E. Grobbee 《European journal of epidemiology》1997,13(5):491-502
Several scores based on symptoms and signs have been developed to assess the presence of heart failure. The goal of this study was to compare six heart failure scores in non-hospitalised subjects and to determine their usefulness in population based research. The scores were applied to 54 participants of a population based study. All underwent a complete medical examination, including chest X-ray, electrocardiography and Doppler echocardiography. Using all information available, a cardiologist, unaware of the results of the scores, clinically classified participants as having no, possible or definite heart failure. Sensitivity, specificity, predictive values and receiver operating characteristics were calculated, using the cardiologist's assessment as a gold standard. The cardiologist judged definite or possible heart failure to be present in 17 persons. All scores had a high sensitivity for the detection of definite heart failure, whereas the study of men born in 1913 and Walma's score had the highest sensitivity for the combination of possible and definite heart failure. Gheorgiade's and the Boston score had the highest positive predictive values. In conclusion, five of the six scores we studied are broadly similar in the detection of heart failure. The men born in 1913 score relies heavily on the assessment of dyspnea, resulting in a relatively large number of false positives. Although the scores are useful in detecting manifest heart failure, objective measurements of cardiac function appear necessary to reduce the false positive rate and accurately detect early stages of heart failure. 相似文献
10.
Experimental research has recently shown that acupuncture induces the formation of o-pioid-like peptides in animals.The role ofβ-endorphin in the mechanism of acupuncture is discussed:some authors maintain the hormonal hypothesis,others the role of neurotransmltters and,up to thepresent,no convincing evidence for either hypothesis has been demonstrated.In order to provide fur-ther evidence,we tested the β-endorphin levels and other parameters(VLP,lymphocyte subsets,NKcells and phagocyte activity of monocytes)in a group of 90 patients suffering from various painful dis-orders treated with acupuncture.Zusanli(ST 36)and Hegu(LI 4)acupoints were selected.A homo-geneous group of 30 subjects was used as control.Evaluation of the above parameters was made with3 series of blood tests;before treatment,30 minutes and 24 hours after acupuncture treatment.In theacupuncture group,the following results were achieved: a)A considerable increase in β-endorphin levels,which remained high even 24 hours afteracup 相似文献