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61.
Total anomalous pulmonary venous connection to the left vertical vein often may be recognized on the plain postero-anterior chest radiograph by the characteristic supracardiac shadow. This "snowman sign" is useful in older patients but rarely is apparent in infancy. In such young patients the authors have discovered a density anterior to the trachea on the lateral chest radiograph. This finding is present prior to the appearance of the snowman sign and should prove useful in the early diagnosis of this anomaly, facilitating prompt, appropriate treatment. Five representative cases are tabulated and developmental and clinical aspects are reviewed. 相似文献
62.
63.
Dietary plasma protein reduces small intestinal growth and lamina propria cell density in early weaned pigs 总被引:2,自引:0,他引:2
Jiang R Chang X Stoll B Fan MZ Arthington J Weaver E Campbell J Burrin DG 《The Journal of nutrition》2000,130(1):21-26
ABSTRACT We quantified the effects of a diet containing animal plasma protein on small intestinal growth and mucosal morphology in early weaned pigs. Ninety-six pigs [14 d old, 4 kg body weight (BW)] were assigned in groups of 32 to three dietary treatments as follows: 1) free access to control diet (C), 2) free access to plasma protein diet (P), and 3) plasma protein, pair-fed to C (PPF). Eight pigs from each group were killed at 2, 4, 8 or 16 d. Over a 16-d period, weight gain in the P group was 43% greater (P < 0.05) than that in C pigs; weight gain was similar in C and PPF groups. Protein intake in the P group was 33% higher (P < 0.05) than that in the PPF group; no significant difference was observed between the C and P groups. Dietary protein conversion efficiencies in both the P and PPF groups were approximately 18% greater (P < 0.05) than those in the C group. Intestinal masses in the three groups did not differ at 2, 4 and 8 d. By 16 d, the jejunal and ileal protein and DNA masses (mg/kg BW) in both the P and PPF groups were lower than those in the C group (P < 0.05). Dietary plasma protein did not affect crypt cell proliferation, crypt depth or villous height in either the jejunum or ileum. However, the intravillous lamina propria cell density in the jejunum was significantly lower (P < 0.05) in P and PPF pigs than in C pigs. Plasma urea concentrations were also 40 and 42% lower (P < 0.05) in the P and PPF groups, respectively, than in the C group. Our results indicate that dietary plasma protein reduces the cellularity of the lamina propria, but not epithelial cell surface of the small intestine. Feeding plasma protein also increased the efficiency of dietary protein utilization, in part, by decreasing amino acid catabolism. 相似文献
64.
Chiun-Fang Chiou Marcia R Weaver Michelle A Bell Todd A Lee James W Krieger 《International journal for quality in health care》2005,17(1):23-30
OBJECTIVE: To develop a multi-attribute outcome measure for children with asthma that allows for the calculation of quality-adjusted life years in cost-effectiveness studies and can also be used to assign preference weights to asthma-symptom-free days. STUDY DESIGN: A literature review and two interviewer-administered surveys. SETTING: Homes or community centers of participants in Seattle, United States. MAIN MEASURE: Visual analog scale (VAS), standard gamble (SG), and relative risk attitude equation techniques were used to estimate two sets of preference weights for 10 health states. The PAHOM was used to record health states of pediatric asthma patients. RESULTS: A total of 94 subjects provided complete responses without any illogical ratings to VAS questions and 101 provided the same to SG questions. The VAS preference weights of the health states range from a maximum of 1 for perfect health to a minimum of 0.03 for severe asthma symptoms, emotional problems, and activity limitations. Those based on the relative risk attitude equation constructed with both VAS and SG preference weights range from 1 to 0.06. The mean PAHOM scores of pediatric asthma patients based on VAS and converted SG preference weights were 0.70 and 0.83, respectively. CONCLUSIONS: The PAHOM calendar can be used to identify asthma patients' health outcomes, to calculate the preference weights of asthma patients' health states, and to estimate the number of symptom-free days. These factors make the PAHOM a promising instrument for use in effectiveness and cost-effectiveness studies in children with asthma. 相似文献
65.
John Weaver Supatra Porasuphatana Pei Tsai Guan-Liang Cao Theodore A Budzichowski Linda J Roman Gerald M Rosen 《Toxicological sciences》2004,81(2):325-331
Neuronal nitric oxide synthase (NOS I) is a Ca(2+)/calmodulin-binding enzyme that generates nitric oxide (NO*) and L-citrulline from the oxidation of L-arginine, and superoxide (O(2)*(-)) from the one-electron reduction of oxygen (O(2)). Nitric oxide in particular has been implicated in many physiological processes, including vasodilator tone, hypertension, and the development and properties of neuronal function. Unlike Ca(2+), which is tightly regulated in the cell, many other divalent cations are unfettered and can compete for the four Ca(2+) binding sites on calmodulin. The results presented in this article survey the effects of various divalent metal ions on NOS I-mediated catalysis. As in the case of Ca(2+), we demonstrate that Ni(2+), Ba(2+), and Mn(2+) can activate NOS I to metabolize L-arginine to L-citrulline and NO*, and afford O(2)*(-) in the absence of L-arginine. In contrast, Cd(2+) did not activate NOS I to produce either NO* or O(2)*(-), and the combination of Ca(2+) and either Cd(2+), Ni(2+), or Mn(2+) inhibited enzyme activity. These interactions may initiate cellular toxicity by negatively affecting NOS I activity through production of NO*, O(2)*(-) and products derived from these free radicals. 相似文献
66.
Michelle N. Vu Kumari G. Lokugamage Jessica A. Plante Dionna Scharton Aaron O. Bailey Stephanea Sotcheff Daniele M. Swetnam Bryan A. Johnson Craig Schindewolf R. Elias Alvarado Patricia A. Crocquet-Valdes Kari Debbink Scott C. Weaver David H. Walker William K. Russell Andrew L. Routh Kenneth S. Plante Vineet D. Menachery 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(32)
The furin cleavage site (FCS), an unusual feature in the SARS-CoV-2 spike protein, has been spotlighted as a factor key to facilitating infection and pathogenesis by increasing spike processing. Similarly, the QTQTN motif directly upstream of the FCS is also an unusual feature for group 2B coronaviruses (CoVs). The QTQTN deletion has consistently been observed in in vitro cultured virus stocks and some clinical isolates. To determine whether the QTQTN motif is critical to SARS-CoV-2 replication and pathogenesis, we generated a mutant deleting the QTQTN motif (ΔQTQTN). Here, we report that the QTQTN deletion attenuates viral replication in respiratory cells in vitro and attenuates disease in vivo. The deletion results in a shortened, more rigid peptide loop that contains the FCS and is less accessible to host proteases, such as TMPRSS2. Thus, the deletion reduced the efficiency of spike processing and attenuates SARS-CoV-2 infection. Importantly, the QTQTN motif also contains residues that are glycosylated, and disruption of its glycosylation also attenuates virus replication in a TMPRSS2-dependent manner. Together, our results reveal that three aspects of the S1/S2 cleavage site—the FCS, loop length, and glycosylation—are required for efficient SARS-CoV-2 replication and pathogenesis.SARS-CoV-2 emerged in late 2019 and has caused the largest pandemic since the 1918 influenza outbreak (1). An unusual feature of SARS-CoV-2 is the presence of a furin cleavage site (FCS) in its spike protein (2). The CoV spike is a trimer of spike proteins composed of the S1 and S2 subunits, responsible for receptor binding and membrane fusion, respectively (1). After receptor binding, the spike protein is proteolytically cleaved at the S1/S2 and S2′ sites to activate the fusion machinery. For SARS-CoV-2, the spike protein contains a novel cleavage motif recognized by the host cell furin protease (PRRAR) directly upstream of the S1/S2 cleavage site that facilitates cleavage prior to virion release from the producer cell. This FCS, not found in other group 2B CoVs, plays a key role in spike processing, infectivity, and pathogenesis as shown by our group and others (3, 4).Importantly, another novel amino acid motif, QTQTN, is found directly upstream of the FCS. This QTQTN motif, also absent in other group 2B CoVs, is often deleted and has been pervasive in cultured virus stocks of the alpha, beta, and delta variants (5–8). In addition, the QTQTN deletion has been observed in a small subset of patient samples as well (9–11). Because this deletion has been frequently identified, we set out to characterize it and determine whether it has consequences for viral replication and virulence. Using our infectious clone (12, 13), we demonstrated that the loss of this motif attenuates SARS-CoV-2 replication in respiratory cells in vitro and pathogenesis in hamsters. The QTQTN deletion results in reduced spike cleavage and diminished capacity to use serine proteases on the cell surface for entry. Importantly, mutations of glycosylation-enabling residues in the QTQTN motif results in similar replication attenuation despite intact spike processing. Together, our results highlight elements in the SARS-CoV-2 spike in addition to the FCS that contribute to increased replication and pathogenesis. 相似文献
67.
Timely follow‐up of positive cancer screening results: A systematic review and recommendations from the PROSPR Consortium 下载免费PDF全文
Chyke A. Doubeni MD MPH Nicole B. Gabler PhD MPH MHA Cosette M. Wheeler PhD Anne Marie McCarthy PhD Philip E. Castle PhD MPH Ethan A. Halm MD MPH Mitchell D. Schnall MD PhD Celette S. Skinner PhD Anna N. A. Tosteson ScD Donald L. Weaver MD Anil Vachani MD Shivan J. Mehta MD MBA Katharine A. Rendle PhD MSW MPH Stacey A. Fedewa PhD Douglas A. Corley MD PhD Katrina Armstrong MD 《CA: a cancer journal for clinicians》2018,68(3):199-216
Timely follow‐up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow‐up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer‐specific recommendations for times to follow‐up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow‐up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow‐up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low‐resource settings. CA Cancer J Clin 2018;68:199–216 . © 2018 American Cancer Society . 相似文献
68.
Mental health consequences of intimate partner abuse: a multidimensional assessment of four different forms of abuse 总被引:1,自引:0,他引:1
Battered women are exposed to multiple forms of intimate partner abuse. This article explores the independent contributions of physical violence, sexual coercion, psychological abuse, and stalking on symptoms of posttraumatic stress disorder (PTSD) and depression among a sample of 413 severely battered, help-seeking women. The authors test the unique effects of psychological abuse and stalking on mental health outcomes, after controlling for physical violence, injuries, and sexual coercion. Mean scores for the sample fall into the moderate to severe range for PTSD and within the moderate category for depression scores. Hierarchical regressions test the unique effects of stalking and psychological abuse, after controlling for physical violence, injuries, and sexual coercion. Psychological abuse and stalking contribute uniquely to the prediction of PTSD and depression symptoms, even after controlling for the effects of physical violence, injuries, and sexual coercion. Results highlight the importance of examining multiple dimensions of intimate partner abuse. 相似文献
69.
Davis NM Weaver V Parks K Lydy MJ 《Archives of environmental contamination and toxicology》2003,44(3):0351-0359
Urban development alters the natural hydrological conditions of many streams and rivers often resulting in the degradation
of water quality, physical habitat, and biotic integrity of lotic systems. Restoration projects attempt to improve and maintain
the ecological integrity of urban streams; however, few projects have quantified improvements to stream ecology following
implementation of restoration measures. This paper summarizes pre-restoration data collected as part of an urban stream restoration
project on Gypsum Creek in Wichita, Kansas. Water quality monitoring revealed eutrophic conditions in the stream and the presence
of pesticides. Channelization has led to changes in physical habitat including bank erosion, sedimentation, loss of substrate
and channel diversity, elimination of in-stream aquatic habitat, removal of riparian vegetation, and decreased base flows.
Benthic macroinvertebrate communities appear degraded with more than 90% of individuals collected described as tolerant to
anthropogenic stressors. Fish communities were assessed with an Index of Biotic Integrity and were rated as poor to fair,
with trophic structure dominated by generalists, no sensitive species present, and one-third of the species collected considered
non-native. Overall, the data collected strongly suggest that site-specific restoration measures need to be implemented in
order to improve and maintain the ecological condition of Gypsum Creek. Recommendations for improvements have been made to
city managers, with implementation beginning in spring 2003 (dependent upon funding availability).
Received: 28 March 2002/Accepted: 24 July 2002 相似文献
70.
An internal fixator for posterior application to short segments of the thoracic, lumbar, or lumbosacral spine. Design and testing 总被引:14,自引:0,他引:14
M H Krag B D Beynnon M H Pope J W Frymoyer L D Haugh D L Weaver 《Clinical orthopaedics and related research》1986,(203):75-98
A new spinal implant has been designed and biomechanical testing completed, intended for application to "short-segment" spinal defects such as disc degeneration, fracture, spondylolisthesis, or tumor. Major improvements over currently available devices include: only 2-3 vertebrae are spanned, not 5-7 as with Harrington rods; true three-dimensional fixation is achieved, preventing such problems as hook or rod dislocation; three-dimensional adjustment is easily accomplished, allowing fracture or spondylolisthesis reduction to be readily performed; attachment to vertebrae is by means of transpedicular screws eliminating deliberate encroachment into the spinal canal, such as Luque wires or Harrington hooks; no special alignment between screws is needed (such as with holes or slots in a plate), allowing screw placement to fully conform to anatomic structures; and laminectomy sites and lumbosacral junction are readily instrumented. Background investigations presented here for design of this device include: CT-defined pedicle morphometry showing that screws may be larger than those currently used; effect of pitch, minor diameter, and tooth profile on screw pull-out strength; mechanical testing of a compact, three-dimensionally adjustable, strong, nonloosening articulating clamp; and establishing of the relationship between depth of penetration and strength of fixation of transpeduncular screws. 相似文献