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Running on water: Three-dimensional force generation by basilisk lizards   总被引:1,自引:0,他引:1  
Water provides a unique challenge for legged locomotion because it readily yields to any applied force. Previous studies have shown that static stability during locomotion is possible only when the center of mass remains within a theoretical region of stability. Running across a highly yielding surface could move the center of mass beyond the edges of the region of stability, potentially leading to tripping or falling. Yet basilisk lizards are proficient water runners, regularly dashing across bodies of water to evade predators. We present here direct measurements of time-averaged force produced by juvenile plumed basilisk lizards (Basiliscus plumifrons) while running across water. By using digital particle image velocimetry to visualize fluid flow induced by foot movement, we show that sufficient support force is generated for a lizard to run across water and that novel strategies are also required to run across a highly yielding surface. Juvenile basilisk lizards produce greatest support and propulsive forces during the first half of the step, when the foot moves primarily vertically downwards into the water; they also produce large transverse reaction forces that change from medial (79% body weight) to lateral (37% body weight) throughout the step. These forces may act to dynamically stabilize the lizards during water running. Our results give insight into the mechanics of how basilisk lizards run across water and, on a broader scale, provide a conceptual basis for how locomotor surface properties can challenge established rules for the mechanics of legged locomotion.  相似文献   
104.
Tsai HH  Hsieh CH  Liou CW  Chen SD  Huang CR  Chang WN 《Pancreas》2005,30(3):285-287
A case of a 22-year-old woman with rare neurologic complications including encephalopathy and acute axonal sensorimotor polyneuropathy in the course of acute pancreatitis is reported. The encephalopathy emerged 3 weeks after the onset of the illness with complete remission being noted 1 week later. The polyneuropathy presented as quadriplegia and respiratory failure that required intubation and partially remitted gradually. There was no pancreatic lesion, no major pancreatic surgery, no sepsis, and no multiple organ failure, all of which had been proposed as the predisposing factors. Severe inflammatory response syndrome (SIRS) that developed during the clinical course of this patient might have induced these neurologic complications.  相似文献   
105.
OBJECTIVES: There is growing evidence suggesting the mutual link between type 2 diabetes mellitus (T2DM) and hepatitis C virus (HCV) infection. However, the impact of HCV infection on the suite of glucose abnormalities has rarely been investigated. The study aimed to determine the difference regarding the prevalence and the characteristics of glucose abnormalities between chronic hepatitis C (CHC) patients and community-based controls. It also aimed to investigate the related clinical, virological, and histological features of glucose abnormalities in HCV infection.
METHODS: Six hundred eighty-three CHC patients and 515 sex-/age-matched controls were included. Oral glucose tolerance test (OGTT) was performed in 522 CHC patients and 447 controls without known T2DM. Clinical data were assessed upon the different stages of glucose abnormalities based on OGTT results.
RESULTS: The prevalence of normoglycemia, IGT, and T2DM in 683 CHC patients was 27.7%, 34.6%, and 37.8%, respectively. There was a significant linear trend from normoglycemia to T2DM in terms of age, family history of T2DM, and advanced liver fibrosis in CHC patients. For those CHC patients without fibrosis, the prevalence of glucose abnormalities reached 67.9% high. All CHC patients carried a significantly higher prevalence than controls regarding those aged <65 yr. For those without known DM, there was a 3.5-fold increase in the prevalence of glucose abnormalities in CHC (65.8%) patients in comparison with controls (35.3%) (OR 3.51, 95% CI 2.70–4.56, P < 0.001).
CONCLUSIONS: CHC patients carried a high prevalence of glucose abnormalities. Determination of glucose abnormalities by OGTT may be suggested.  相似文献   
106.
We report a nonmyeloablative allogeneic bone marrow transplant (allo-BMT) from an HLA-matched unrelated donor in a case of acute myeloid leukemia (AML), M2 with t(8;21)(q22;q22) and the presence of orbital granulocytic sarcoma (GS), who had residual tumor after conventional chemotherapy. The course of BMT was well tolerated, with no major procedure-related toxicity. The residual orbital GS regressed completely 4 months after BMT. She is currently 19 months post BMT, disease-free. To our knowledge, this is the first reported pediatric patient with AML, GS and t(8;21)(q22;q22) who received a nonmyeloablative allo-BMT.  相似文献   
107.
PURPOSE: This study examines the relationship between the first set of quality measures (QMs) published by the Centers for Medicare and Medicaid Services on the Nursing Home Compare Web site and five nursing home structural characteristics: ownership, chain affiliation, size, occupancy, and hospital-based versus freestanding status. DESIGN AND METHODS: Using robust linear regressions, we examined the values of the QMs at first publication and their change over the first five reporting periods, in relation to facility characteristics. RESULTS: There were significant baseline differences associated with these facility characteristics. Pain, physical restraints, and delirium exhibit a clear downward trend, with differences between the first QM reporting period and the fifth ranging from 12.7% to 46.0%. However, there were only minimal differences in trends associated with facility characteristics. This suggests that the relative position of facilities on these measures did not change much within this time period. The variation by facility type was larger for the short-stay QMs than for the long-stay measures. IMPLICATIONS: Those QMs that show an improvement exhibit it across all types of facilities, irrespective of initial quality levels. Although a number of alternatives may explain this positive trend, the trend itself suggests that report cards, to the extent that they are effective, are so for all facility types but only some QMs.  相似文献   
108.
Compared with abundant catechins, strictinin is a minor constituent in teas and has been demonstrated to possess inhibitory potency on influenza virus. In this study, strictinin was found as the major phenolic compound in Pu’er teas produced from leaves and buds of wild trees. Due to its thermal instability, strictinin, in tea infusion or in an isolated form, was completely decomposed to ellagic acid and gallic acid after being autoclaved for 7 minutes. A plaque reduction assay was employed to compare the relative inhibitory potency between strictinin and its thermally degraded products against human influenza virus A/ Puerto Rico/8/34. The results showed that the antiviral activity of ellagic acid regardless of the presence or absence of gallic acid was significantly higher than that of strictinin. Thermal degradation of strictinin to ellagic acid and gallic acid seems to be beneficial for the preparation of Pu’er teas in terms of enhancing antiviral activity.  相似文献   
109.
Gynura bicolor (Roxb. & Willd.) DC. is widely distributed in certain areas of Asia and is very popular in vegetarian cuisine in Taiwan. This study investigates the effects of G. bicolor extracts with different polarities of 80 mg/kg body weight (BW) G. bicolor alcohol extract, 80 mg/kg BW G. bicolor water extract, and 80 mg/kg BW G. bicolor ether extract on Fe bioavailability using the hemoglobin repletion efficiency assay. Wistar rats were assigned to five groups: a group receiving an iron-deficient (ID) diet; a group receiving an ID diet supplemented with ferrous sulfate (20 mg Fe/kg BW); and three groups receiving ID diets supplemented with ferrous sulfate and one of G. bicolor alcohol extract, G. bicolor water extract, or G. bicolor water extract. The results indicated that the levels of hemoglobin, serum iron, serum ferritin, liver ferritin, hemoglobin regeneration efficiency, relative biological value, and hepcidin all were significantly higher than those of the ID diet group. Besides, the iron transporter divalent metal transporter-1 was significantly reduced, but iron release protein expression of ferroportin was significantly increased. It was concluded that G. bicolor extracts may promote iron bioavailability and regulate the expressions of divalent metal transporter-1 and ferroportin.  相似文献   
110.
Molecular basis of weak D in Taiwanese   总被引:4,自引:0,他引:4  
Two genes, RHD and RHCE, encode the antigens of the RH blood group system. The weak D phenotype is caused by many different RHD alleles encoding aberrant RhD proteins, resulting in distinct serologic phenotypes and anti-D immunization. We analyzed seven weak D phenotypes excluding Del, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing methods to detect the changes of all ten RHD exons. The results show that there are four types of weak D in Taiwanese: one case each for CGG to CAG mutation at codon 10, GTG to ATG mutation at codon 174, and GTG to GAG mutation at codon 270, and four cases for GGT to GAT mutation at codon 282. In conclusion, we present the first data of a molecular basis of weak D in Taiwanese, which suggest a clinically relevant potential for anti-D immunization and may improve transfusion strategy in weak D Taiwanese patients.  相似文献   
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