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111.
112.
J Frank S Sinclair S Hogg-Johnson H Shannon C Bombardier D Beaton D Cole 《CMAJ》1998,158(12):1625-1631
Despite the publication in the mid-1990s of comprehensive practice guidelines for the management of acute low-back pain, both in the United States and elsewhere, this ubiquitous health problem continues to be the main cause of workers'' compensation claims in much of the Western world. This paper represents a synthesis of the intervention studies published in the last 4 years and is based on a new approach to categorizing these studies that emphasizes the stage or phase of back pain at the time of intervention and the site or agent of the intervention. Current thinking suggests that medical management in the first 3-4 weeks after the onset of pain should be generally conservative. Several studies of rather heterogeneous interventions focusing on return to work and implemented in the subacute stage (3-4 to 12 weeks after the onset of pain) have shown important reductions in time lost from work (by 30% to 50%). There is substantial evidence indicating that employers who promptly offer appropriately modified duties can reduce time lost per episode of back pain by at least 30%, with frequent spin-off effects on the incidence of new back-pain claims as well. Finally, newer studies of guidelines-based approaches to back pain in the workplace suggest that a combination of all these approaches, in a coordinated workplace-linked care system, can achieve a reduction of 50% in time lost due to back pain, at no extra cost and, in some settings, with significant savings. 相似文献
113.
Hypohydration effects on skeletal muscle performance and metabolism: a 31P-MRS study 总被引:1,自引:0,他引:1
Montain Scott J.; Smith Sinclair A.; Mattot Ralph P.; Zientara Gary P.; Jolesz Ferenc A.; Sawka Michael N. 《Journal of applied physiology》1998,84(6):1889-1894
The purpose of this study was to determinewhether hypohydration reduces skeletal muscle endurance and whetherincreased H+ andPi might contribute to performancedegradation. Ten physically active volunteers (age 21-40 yr)performed supine single-leg, knee-extension exercise to exhaustion in a1.5-T whole body magnetic resonance spectroscopy (MRS) system wheneuhydrated and when hypohydrated (4% body wt).31P spectra were collected at arate of one per second at rest, exercise, and recovery, and weregrouped and averaged to represent 10-s intervals. The desired hydrationlevel was achieved by having the subjects perform 2-3 h ofexercise in a warm room (40°C dry bulb, 20% relative humidity)with or without fluid replacement 3-8 h before the experiment.Time to fatigue was reduced (P < 0.05) by 15% when the subjects were hypohydrated [213 ± 12 vs. 251 ± 15 (SE) s]. Muscle strength was generally notaffected by hypohydration. Muscle pH andPi/-ATP ratio were similarduring exercise and at exhaustion, regardless of hydration state. The time constants for phosphocreatine recovery were also similar betweentrials. In summary, moderate hypohydration reduces muscle endurance,and neither H+ norPi concentration appears to berelated to these reductions. 相似文献
114.
In vitro shoot culture and microtuber induction in the steroid yam Dioscorea composita Hemsl 总被引:4,自引:0,他引:4
Alizadeh Sedigeh Mantell Sinclair H. MariaViana Ana 《Plant Cell, Tissue and Organ Culture》1998,53(2):107-112
The individual effects of sucrose, plant growth regulators and basal salt media formulations were investigated on microtuber
induction and development in shoot cultures of the steroid yam Dioscorea composita. Sucrose at 8% (w/v) was the single most
significant medium constituent for microtuber induction. Of the four cytokinins tested, 6-benzyladenine at 1.25 and 2.5 μM
showed strong inhibitory effects on microtuber induction. By contrast, the auxins α-naphthaleneacetic acid and indole-3-butyric
acid at 5.0 μM showed striking promotive effects on microtuber induction and growth. In the presence of either one of these
auxins at 5.0 μM shoot cultures produced microtubers weighing 300–400 mg fresh weight whilst kinetin, 6-(γ,γ-dimethylallylamino)-purine,
6-benzyladenine and abscisic acid failed to promote microtuber growth (microtubers weighed generally <200 mg). Media formulations
Lloyd and MacCown and White supported the lowest frequencies of microtuber induction when kinetin was present at 2.5 μM. Anderson
Rhododendron was as effective as Murashige and Skoog overall in promoting both microtuber induction and growth. When removed
from cultures and planted in sterilized moist sand, microtubers sprouted readily (60–87% within 2 weeks) and produced vigorous
shoot growth and after 5–7 months minitubers of sizes (30–80 g) suitable for direct field planting.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
115.
Markus K Muellner Barbara Mair Yasir Ibrahim Claudia Kerzendorfer Hannelore Lechtermann Claudia Trefzer Freya Klepsch André C Müller Ernestine Leitner Sabine Macho‐Maschler Giulio Superti‐Furga Keiryn L Bennett José Baselga Uwe Rix Stefan Kubicek Jacques Colinge Violeta Serra Sebastian MB Nijman 《Molecular systems biology》2015,11(2)
116.
117.
Clara?D. van?Karnebeek William?S. Sly Colin?J. Ross Ramona Salvarinova Joy Yaplito-Lee Saikat Santra Casper Shyr Gabriella?A. Horvath Patrice Eydoux Anna?M. Lehman Virginie Bernard Theresa Newlove Henry Ukpeh Anupam Chakrapani Mary?Anne Preece Sarah Ball James Pitt Hilary?D. Vallance Marion Coulter-Mackie Hien Nguyen Lin-Hua Zhang Amit?P. Bhavsar Graham Sinclair Abdul Waheed Wyeth?W. Wasserman Sylvia Stockler-Ipsiroglu 《American journal of human genetics》2014,94(3):453-461
Four children in three unrelated families (one consanguineous) presented with lethargy, hyperlactatemia, and hyperammonemia of unexplained origin during the neonatal period and early childhood. We identified and validated three different CA5A alterations, including a homozygous missense mutation (c.697T>C) in two siblings, a homozygous splice site mutation (c.555G>A) leading to skipping of exon 4, and a homozygous 4 kb deletion of exon 6. The deleterious nature of the homozygous mutation c.697T>C (p.Ser233Pro) was demonstrated by reduced enzymatic activity and increased temperature sensitivity. Carbonic anhydrase VA (CA-VA) was absent in liver in the child with the homozygous exon 6 deletion. The metabolite profiles in the affected individuals fit CA-VA deficiency, showing evidence of impaired provision of bicarbonate to the four enzymes that participate in key pathways in intermediary metabolism: carbamoylphosphate synthetase 1 (urea cycle), pyruvate carboxylase (anaplerosis, gluconeogenesis), propionyl-CoA carboxylase, and 3-methylcrotonyl-CoA carboxylase (branched chain amino acids catabolism). In the three children who were administered carglumic acid, hyperammonemia resolved. CA-VA deficiency should therefore be added to urea cycle defects, organic acidurias, and pyruvate carboxylase deficiency as a treatable condition in the differential diagnosis of hyperammonemia in the neonate and young child. 相似文献
118.
Self-organization is a key condition to the success of community-based conservation initiatives, including those recognized
by the Equator Initiative of the UNDP. This paper contributes to emerging scholarship that focuses on community-based conservation
in South Asia and in particular examines self-organization strategies within a small-scale community-based conservation initiative
in a cross-cultural setting to further understanding about how such initiatives originate, sustain and grow. This is achieved
through a case study of the Baripada Forest Protection Initiative in India by utilizing in-depth interviews and focus groups.
In addition to certain often-cited strategies for self-organization, the Baripada initiative included unique features of self-organization
such as village community design, implementation and adaptation of rules for local natural resources use and conservation,
little need for financial support, and significant mobilization of human resources. These strategies, along with emerging
social learning opportunities (e.g., a community plant diversity register) inspired by the Baripada initiative, inform and
enrich the criteria for designing and evaluating conservation and development initiatives, irrespective of their scale. 相似文献
119.
Mathur J Radhamony R Sinclair AM Donoso A Dunn N Roach E Radford D Mohaghegh PS Logan DC Kokolic K Mathur N 《Plant physiology》2010,154(4):1573-1587
Photoconvertible fluorescent proteins (FPs) are recent additions to the biologists' toolbox for understanding the living cell. Like green fluorescent protein (GFP), monomeric EosFP is bright green in color but is efficiently photoconverted into a red fluorescent form using a mild violet-blue excitation. Here, we report mEosFP-based probes that localize to the cytosol, plasma membrane invaginations, endosomes, prevacuolar vesicles, vacuoles, the endoplasmic reticulum, Golgi bodies, mitochondria, peroxisomes, and the two major cytoskeletal elements, filamentous actin and cortical microtubules. The mEosFP fusion proteins are smaller than GFP/red fluorescent protein-based probes and, as demonstrated here, provide several significant advantages for imaging of living plant cells. These include an ability to differentially color label a single cell or a group of cells in a developing organ, selectively highlight a region of a cell or a subpopulation of organelles and vesicles within a cell for tracking them, and understanding spatiotemporal aspects of interactions between similar as well as different organelles. In addition, mEosFP probes introduce a milder alternative to fluorescence recovery after photobleaching, whereby instead of photobleaching, photoconversion followed by recovery of green fluorescence can be used for estimating subcellular dynamics. Most importantly, the two fluorescent forms of mEosFP furnish bright internal controls during imaging experiments and are fully compatible with cyan fluorescent protein, GFP, yellow fluorescent protein, and red fluorescent protein fluorochromes for use in simultaneous, multicolor labeling schemes. Photoconvertible mEosFP-based subcellular probes promise to usher in a much higher degree of precision to live imaging of plant cells than has been possible so far using single-colored FPs. 相似文献
120.