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排序方式: 共有2717条查询结果,搜索用时 15 毫秒
11.
D. MacDonald E. Lau E. L. P. Chan T. Mak J. Woo P. C. Leung R. Swaminathan 《Calcified tissue international》1992,51(6):412-414
Summary Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)2D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25 (OH)2D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture. 相似文献
12.
We undertook an analysis of the hazard functions derived from results published by the Parkinson Study Group following their investigation of deprenyl. Our findings indicate that the action of deprenyl is transient rather than sustained. We also infer that this effect may be mediated through alleviation of symptoms rather than by neuroprotection. 相似文献
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14.
Koon-Hou Mak 《European heart journal》2007,28(6):655-656
Myocardial infarction is an important public health problemworldwide. Rapid restoration of flow remains as the foundationfor life-saving treatment of patients with ST-segment elevationmyocardial infarction (STEMI). In Europe, it is heartening tonote that the utilization of reperfusion therapies was increasingly,with the proportion rising from 55.8% in 20002001 to63.9% in 2004, based on the first and second Euro Heart Surveysof Acute Coronary Syndromes, respectively.1 Notably, patientswere more likely to receive primary percutaneous coronary intervention(increased from 37 to 59% over the same period),1 probably becauseof the favourable results derived from 相似文献
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Robert H. K. Mak 《Pediatric nephrology (Berlin, Germany)》1998,12(8):637-642
Insulin and branched-chain amino acid (BCAA) metabolism was studied in 14 adolescents with uremia on hemodialysis. Glucose
tolerance was measured by intravenous glucose tolerance tests. Insulin sensitivity was measured by the euglycemia clamp technique.
Insulin secretion during constant hyperglycemia was measured by the hyperglycemic clamp technique. Fasting plasma BCAA concentrations
were compared with data from 8 adolescent controls, whereas insulin indices were compared with 8 young adults controls and
with published normal data in adolescents. The patients could be further sub-divided into two groups with respect to their
growth velocity standard deviation score (GVSDS). Group 1 consisted of 7 patients with GVSDS less than −2. This group demonstrated
insulin resistance, glucose intolerance, and low insulin secretion. This group also had low plasma valine, leucine, and isoleucine
concentrations compared with control values. Group 2 consisted of 7 patients with GVSDS more than −2. This group demonstrated
insulin resistance, but normal glucose tolerance and normal insulin secretion. Plasma valine, leucine, and isoleucine concentrations
in group 2 were not different from control values. Total plasma BCAA correlated with glucose tolerance index and with insulin
secretion, but not with insulin sensitivity. Growth failure in uremia is associated with glucose intolerance, hypoinsulinemia,
and low plasma BCAA concentrations. Impaired utilization of conventional energy sources leading to preferential oxidation
of BCAA may contribute to reduced anabolism and growth failure in uremia.
Received October 8, 1997; received in revised form February 3, 1998; accepted February 6, 1998 相似文献
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18.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献
19.
Does the deletion within T cell receptor β-chain gene of NZW mice contribute to autoimmunity in (NZB × NZW)F1mice? 总被引:4,自引:0,他引:4
Y Yanagi S Hirose R Nagasawa T Shirai T W Mak T Tada 《European journal of immunology》1986,16(9):1179-1182
To determine the transacting genetic factors of NZW contributing to the development of autoimmune disease in (NZB X NZW)F1 (B/W F1) mice, we examined the relationship between the T cell receptor beta chain gene deletion and the severity of autoimmune manifestations in 76 B/W F1 X NZB backcross mice. Very high association between the T cell receptor beta chain gene deletion and the development of autoimmune manifestations including the production of IgG anti-DNA antibodies and circulating retroviral gp70 immune complexes was observed, indicating that a defect in the NZW T cell receptor beta chain gene or a locus closely linked to it contributes to the autoantibody formation in B/W F1. 相似文献
20.
WSX-1 is required for resistance to Trypanosoma cruzi infection by regulation of proinflammatory cytokine production 总被引:6,自引:0,他引:6
Hamano S Himeno K Miyazaki Y Ishii K Yamanaka A Takeda A Zhang M Hisaeda H Mak TW Yoshimura A Yoshida H 《Immunity》2003,19(5):657-667
WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors and is essential for resistance to Leishmania major infection. In the present study, we demonstrated that WSX-1 was also required for resistance to Trypanosoma cruzi. WSX-1-/- mice exhibited prolonged parasitemia, severe liver injury, and increased mortality over wild-type mice. WSX-1-/- splenocytes produced enhanced levels of Th2 cytokines, which were responsible for the prolonged parasitemia. Massive necroinflammatory lesions were observed in the liver of infected WSX-1-/- mice, and IFN-gamma that was overproduced in WSX-1-/- mice compared with wild-type mice was responsible for the lesions. In addition, vast amounts of various proinflammatory cytokines, including IL-6 and TNF-alpha, were produced by liver mononuclear cells in WSX-1-/- mice. Thus, during T. cruzi infection, WSX-1 suppresses liver injury by regulating production of proinflammatory cytokines, while controlling parasitemia by suppression of Th2 responses, demonstrating its novel role as an inhibitory regulator of cytokine production. 相似文献