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91.
The symposium took place in Tel Aviv on October 17-20th, 1982. Over 100 investigators and clinicians from Europe, the United States, Japan, and Israel participated. The first day was devoted to risk factors for atherosclerosis in childhood. New evidence, supporting the predominance of the genetic factor in determining the risk for coronary atherosclerosis was reviewed. It included a high incidence of preatherosclerotic changes in children of population groups with a high incidence of coronary artery disease (Eastern Finland, Caucasians in the United States, Ashkenazi Jews in Israel), compared with low incidence of preatherosclerotic changes in the coronary arteries of children of population groups with low incidence of coronary artery disease (Western Finland, Blacks in the United States, Yemenite Jews, and Bedouins in Israel). The risk factors that can be influenced, including hypertension, hyperlipemia, and smoking at a young age, were reviewed. In the discussion it was emphasized that the long-term results of changing the lifestyle of whole population groups are not yet well recognized. Several studies of mass intervention aimed at primary prevention are now being performed. 相似文献
92.
Heart studies were carried out in 7 patients with end-stage renal disease (ESRD) who underwent parathyroidectomy for secondary hyperparathyroidism. The studies, which included echocardiography and equilibrium radionuclide angiography (ERNA), were performed prior to parathyroidectomy and 2 weeks, 3 months, and 6 months following it, on a nondialytic day. Heart rate decreased from 89.3 +/- 1.3 to 81.4 +/- 1.5 min-1 (p less than 0.001) following parathyroidectomy and returned to the initial level at 3- and 6-month examination. Cardiac output decreased from 3170 +/- 68 to 2943 +/- 57 ml/min (p less than 0.01) following parathyroidectomy and returned to basal level on 3 and 6-month determinations. End-diastolic dimension (EDD), end-systolic dimension (ESD), septal and posterior wall thickness and shortening fraction (SF) as measured by echocardiography were normal prior to parathyroidectomy and remained unchanged following it. Left ventricular ejection fraction (LVEF), end-diastolic and end-systolic volumes measured by ERNA did not change following parathyroidectomy. This study suggests that hyperparathyroidism has little effect on cardiac performance and, except for a short-lived decrease in heart rate and cardiac output, parathyroidectomy does not affect cardiac performance when performed in patients with preoperatively normal cardiac output. 相似文献
93.
A number of surgical clips and other metallic materials embedded within patients have ferromagnetic properties that present a potential hazard when in the strong fields associated with magnetic resonance imaging. Several types of magnetometers and metal detectors were investigated as possible pre-imaging screening devices. The sensitivities and costs of these devices are given. 相似文献
94.
95.
96.
Neufeld ND 《Pediatrics》2005,116(1):292; author reply 292-292; author reply 293
97.
DeVito TJ Drost DJ Pavlosky W Neufeld RW Rajakumar N McKinlay BD Williamson PC Nicolson R 《Journal of the American Academy of Child and Adolescent Psychiatry》2005,44(12):1301-1308
OBJECTIVE: Although abnormalities of neural circuits involving the cortex, striatum, and thalamus are hypothesized to underlie Tourette's disorder, the neuronal abnormalities within components of these circuits are unknown. The purpose of this study was to examine the cellular neurochemistry within these circuits in Tourette's disorder using proton magnetic resonance spectroscopy, a method that has not previously been used in neurobiological investigations of the disorder. METHOD: Proton magnetic resonance spectroscopic imaging examinations were conducted in 25 males with Tourette's disorder (age 10.9 +/- 2.0 years) and 32 male comparison subjects (age 11.5 +/- 2.7 years). Spectra from frontal cortex, caudate nucleus, putamen, and thalamus were analyzed, and N-acetylaspartate, creatine, choline, myoinositol, and glutamate + glutamine were quantified and compared between the groups. RESULTS: Patients with Tourette's disorder demonstrated a reduction in N-acetylaspartate and choline in the left putamen, along with reduced levels of creatine bilaterally in the putamen. In the frontal cortex, patients had significantly lower concentrations of N-acetylaspartate bilaterally, lower levels of creatine on the right side, and reduced myoinositol on the left side. CONCLUSIONS: The results of this study suggest compromised neuronal integrity and deficits in density of neuronal and nonneuronal cells in components of the neural circuits implicated in Tourette's disorder. 相似文献
98.
Background Sequentially evolving intracranial bilateral haematomas, where the second haematoma develops after the surgical removal of
the first one is rarely reported.
Aim To report a patient who developed an epidural haematoma after evacuation of a contralateral subdural haematoma.
Methods A 49-year-old male was admitted to our department after head injury. A brain computerized tomography (CT) scan revealed an
acute subdural haematoma in the right temporal area which was evacuated. During his stay in the intensive care unit, he was
submitted to intracranial pressure monitoring, which soon rose.
Results A new CT scan showed an acute epidural haematoma in the contralateral parietal area that was also evacuated.
Conclusions While rising intracranial pressure after the evacuation of a traumatic haematoma is usually attributed to brain oedema or
recurrent haematoma at the craniotomy site, the development of a contralateral epidural haematoma requiring surgical treatment
should not be overlooked. 相似文献
99.
Ramakrishnan U Neufeld LM González-Cossío T Villalpando S García-Guerra A Rivera J Martorell R 《The Journal of nutrition》2004,134(4):898-903
The impact of iron-only supplements (FE) versus multiple micronutrient supplements containing iron (MM) during pregnancy on iron status was assessed in a subsample (n = 453) of women who participated in a randomized double-blind trial in Mexico. Compliance, monitored by observation, was high (>85%). The two groups were similar at recruitment (<13 wk gestation) for various sociodemographic characteristics and for mean hemoglobin (Hb) concentrations and prevalence of anemia (Hb < 110 g/L; 11%). However, mean serum ferritin was higher (P < 0.05) in the MM group (n = 142) compared to the FE group (n = 148) and the prevalence of iron deficiency (serum ferritin < 12 micro g/L) was lower in the MM group (44.4%) compared to the FE group (57.4%). By the third trimester, almost half the women were anemic in both groups, and mean Hb (g/L) was lower for the MM group (104.2; 95% CI: 102.5, 106.0) compared to the FE group (108.1; 95% CI: 106.4, 109.8) after adjusting for baseline serum ferritin. In contrast, there were no differences in Hb concentrations at 1 mo postpartum or in mean ferritin and prevalence of iron deficiency at 32 wk gestation and 1 mo postpartum (90.9 and 45.1% for the MM group; 92.6 and 47.3% for the FE group, respectively). In conclusion, rather than improve Hb or iron status relative to FE-only supplements as hypothesized, MM supplements may have slightly reduced Hb concentrations during pregnancy. Neither supplement was able to meet iron needs as evidenced by dramatic increases in anemia and iron deficiency by the end of pregnancy. 相似文献
100.
Semaphorin-3F is an inhibitor of tumor angiogenesis 总被引:15,自引:0,他引:15
Kessler O Shraga-Heled N Lange T Gutmann-Raviv N Sabo E Baruch L Machluf M Neufeld G 《Cancer research》2004,64(3):1008-1015
The neuropilin-1 (np1) and neuropilin-2 (np2) receptors form complexes with type-A plexins. These complexes serve as signaling receptors for specific class-3 semaphorins. Np1 and np2 function in addition as receptors for heparin-binding forms of vascular endothelial growth factor (VEGF), such as VEGF(165). Human umbilical vein endothelial cells (HUVEC) express tyrosine-kinase receptors for VEGF and basic fibroblast growth factor (bFGF), as well as np1, np2, and several type-A plexins. We have found that semaphorin-3F (s3f), a semaphorin which signals through the np2 receptor, was able to inhibit VEGF(165), as well as bFGF-induced proliferation of HUVECs. Furthermore, s3f inhibited VEGF as well as bFGF-induced phosphorylation of extracellular signal-regulated kinase-1/2. Our experiments indicate that bFGF does not bind to neuropilins, nor does s3f inhibit the binding of bFGF to FGF receptors. It is therefore possible that s3f inhibits the activity of bFGF by a mechanism that requires active s3f signal transduction rather than by inhibition of bFGF binding to FGF receptors. s3f also inhibited VEGF(165), as well as bFGF-induced in vivo angiogenesis as determined by the alginate micro-encapsulation and Matrigel plug assays. Overexpression of s3f in tumorigenic human HEK293 cells inhibited their tumor-forming ability but not their proliferation in cell culture. The tumors that did develop from s3f-expressing HEK293 cells developed at a much slower rate and had a significantly lower concentration of tumor-associated blood vessels, indicating that s3f is an inhibitor of tumor angiogenesis. 相似文献