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91.
BACKGROUND: The magnitudes of the first (WI1) and the second wave-intensity peak (WI2) during the ejection period can be used as indices of left ventricular (LV) contractility and relaxation, respectively. However, use of WI to characterize LV dp/dt and the end-diastolic volume (V ed) relationship may be more problematic, as WI may be affected by changes in preload. METHODS AND RESULTS: The LV pressure-volume data sets, consisting of 23 recordings obtained by the conductance method from 12 heart disease patients, were studied. End-systolic elastance (E es) and volume-axis-intercept (V0) were calculated with varying preload. Time constant of LV relaxation (tau), V ed, and WI were calculated from steady-state averaged data. The E es showed a weak correlation with WI1 (r = 0.46, p < 0.05) but a better correlation with preload-adjusted WI1 [WI1/V ed; r=0.86, WI1/V(ed)2; r = 0.92, WI1/(V ed - V0)2; r = 0.89, all p < 0.01]. Similarly, tau did not correlate with WI2 but did correlate with preload-adjusted WI2 [WI2/V ed; r = -0.73, WI2/V(ed) 2; r = -0.63, WI2/(V ed - V0)2; r = -0.78, all p < 0.01]. CONCLUSIONS: These data demonstrate the importance of preload-adjustment when using the WI index for simultaneous assessment of LV contractility and relaxation.  相似文献   
92.
The amounts of 3-methylhistidine, N epsilon,N epsilon-dimethyllysine, N epsilon, N epsilon, N epsilon-trimethyllysine, NG,NG-dimethylarginine, and NG,N'G-dimethylarginine were determined in the urine specimens of healthy subjects and patients of corresponding ages with Duchenne, limb-girdle, and congenital types of muscular dystrophy, and motor neuron diseases. The amount of excretion of 3-methylhistidine decreased and that of NG,NG-dimethylarginine increased significantly in Duchenne and limb-girdle types of muscular dystrophy, but not in diseases with neurogenic muscular atrophy. The decrease of 3-methylhistidine was observed consistently throughout the course of the Duchenne type of muscular dystrophy. The amounts of the other methylamino acids both in myogenic and neurogenic myopathies were not different from those in healthy subjects.  相似文献   
93.
Purpose:We aimed to investigate the performance of high resolution-diffusion-weighted imaging (HR-DWI) using readout-segmented echo-planar imaging in visualizing malignant breast lesions and evaluating their extent, using pathology as a reference.Methods:This retrospective study included patients who underwent HR-DWI with surgically confirmed malignant breast lesions. Two radiologists blinded to the final diagnosis evaluated HR-DWI independently and identified the lesions, measuring their maximum diameters. Another radiologist confirmed if those lesions were identical to the pathology. The maximum diameters of the lesions between HR-DWI and pathology were compared, and their correlations were calculated using Spearman’s correlation coefficient. Apparent diffusion coefficient (ADC) values of the lesions were measured.Results:Ninety-five mass/64 non-mass lesions were pathologically confirmed in 104 females. Both radiologists detected the same 93 mass lesions (97.9%). Spearman’s correlation coefficient for mass lesions were 0.89 and 0.90 (P < 0.0001 and 0001) for the two radiologists, respectively. The size differences within 10 mm were 90.3% (84/93) and 94.6% (88/93) respectively. One radiologist detected 35 non-mass lesions (54.7%) and another radiologist detected 32 non-mass lesions (50.0%), of which 28 lesions were confirmed as identical. Spearman’s correlation coefficient for non-mass lesions were 0.59 and 0.22 (P = 0.0002 and 0.22), respectively. The mean ADC value of mass lesions and non-mass lesions were 0.80 and 0.89 × 10−3 mm2/s, respectively.Conclusion:Using HR-DWI, malignant mass lesions were depicted with excellent agreement with the pathological evaluation. Approximately half of the non-mass lesions could not be identified, suggesting a current limitation of HR-DWI.  相似文献   
94.
Toll like receptors are primary sensors of both innate and adaptive immune systems. They activate APCs and influence T-cell function in inflammatory autoimmune response. Studies have shown that TLR manipulation may lead to either tolerance or trigger autoimmunity. Using diabetogenic and subdiabetogenic multiple low doses of streptozotocin, we demonstrate here that Pam3 CYS-CK4 a TLR-2 agonist, enhances and promotes diabetes in C57BL/6 male mice following increased apoptosis of β islet cells. FACS analysis of isolated pancreatic lymph node cells revealed significant increased number of macrophages, dendritic cells, CD4+ TNF-α+, CD4+ IFN-γ+ and most significantly, CD4+ IL-17+ and reduced number of CD25+Fox p3+ T cells after Pam3CSK4 treatment. Genetic deletion of IFN-γ prevents whereas deletion of IL-17 reduced severity of Pam3CSK4-induced enhancement of diabetes. TLR-2 agonist-enhanced diabetogenesis is also influenced by enhanced influx of antigen presenting cells and suppression of regulatory T cell activity.  相似文献   
95.
96.
We describe herein a case of unilateral pulmonary agenesis (PA) with oesophageal atresia (EA)/tracheoesophageal fistula (TEF) that was diagnosed prenatally and repaired by esophagoesophagostomy with stable postoperative course. The patient was born at 34 weeks gestation, after ultrasonography at 22 weeks gestation showed possible right-sided diaphragmatic eventration or PA and EA was subsequently suspected due to hydramnios. The initial X-ray showed mediastinal shift to the right, and coil up sign of the nasogastric tube, without intracardiac anomaly. Immediately after the diagnosis of EA/TEF and unilateral PA on day 0, the patient was intubated in the operating room, and a gastrostomy tube was placed. After pulmonary status stabilized, at 4 days old, EA/TEF was repaired through a thoracotomy in the right 4th intercostal space. The right main bronchus was noted to continue into the distal oesophagus; this fistula was ligated and divided, and a single-layer esophagoesophagostomy was performed under mild tension with one vertebral gap. The neonate was maintained on mechanical ventilation and gradually weaned to extubation at 7 days old. The postoperative course was uneventful, with the exception of prolonged jaundice that emerged at 3 months old. Laparoscopic cholangiography at that time excluded biliary atresia, and jaundice resolved spontaneously. The patient has not shown any respiratory symptoms or feeding difficulties as of the 12-month follow-up.  相似文献   
97.
Summary As congenital malformations may be caused by perturbations of glycolytic flux on early embryogenesis [16], effects of hypoglycaemia were investigated by using rat embryo organ culture. Nine and one-half day old rat embryos were grown in vitro for 48 h (day 9 1/2 to 11 1/2) in the presence of hypoglycaemic serum for different hours during the culture period. Hypoglycaemic serum was obtained from rats given insulin intraperitoneally. On exposure to hypoglycaemic serum during the first 24 h of culture (day 9 1/2 to 10 1/2), embryos showed marked growth retardation and had increased frequencies of neural lesions (42.7% versus 0%, p<0.01), in contrast to hypoglycaemic exposure during the second 24 h of culture (day 10 1/2 to 11 1/2), where only minor growth retardation and low frequencies of neural lesions (2.4% versus 0%, NS) were seen. Even exposure to hypoglycaemic serum for a relatively short period (8 h) during the first 24 h of culture resulted in neural lesions at the frequency of 9.3–13.3%. The embryos exposed to hypoglycaemia demonstrated decreased glucose uptake and lactic acid formation, indicating decreased energy production via glycolysis that constitutes the principal energy pathway at this stage of embryonic development. These results suggest that hypoglycaemia during critical periods of embryogenesis has adverse effects on the development of the embryo and these effects might be mediated through metabolic interruption of embryogenesis.  相似文献   
98.
99.
New RNA replicases were isolated and purified from Escherichia coli Q13 infected with SP or FI phages showing different serological properties. These replicases showed a template specificity different from that of Qbeta replicase.  相似文献   
100.
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