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1.
When the original idea was conceived 8 years ago to develop a surgical technique for the treatment of fetal hydrocephalus, the pathway towards prenatal surgery for this affection was totally unexplored. The operation appeared to be feasible because of the possibility of a ventriculo-amniotic shunt. The most important steps in our experimental studies in the ewe were creation of a fetal hydrocephalus by injection of a suspension of kaolin powder into cisterna magna; the treatment of the hydrocephalus by a mini-ventriculo-amniotic shunt, by cutting the cardiac end of a low pressure Pudenz pediatric catheter. Lambs were delivered by Cesarean two weeks before end of gestation. Coronal sections of brains of control and treated lambs showed reduction in hydrocephalus in the latter. These findings were the basis for the application of the method to treatment of human fetal hydrocephalus.  相似文献   
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Reconstruction for symptomatic anterior cruciate deficient knees has yielded varying success rates. Prosthetic cruciate replacement has recently become a potentially attractive alternative. The results of the Gore-Tex polytetrafluoroethylene ligament, which is intended as a permanent replacement, are reported. Eighty-two patients were followed prospectively, mean age was 28 years (range, 16 to 51 years) and mean followup was 18 months (range, 12 to 30 months). Subjective scores improved in all categories, including pain, swelling, giving way, locking, and stair climbing. All patients without complications had no episodes of actual giving way, considered themselves improved, and returned to activities of daily living at 3 weeks and athletics at 8 months. Range of motion lacking at 3 months was 2 degrees of extension and 10 degrees of flexion, and at 12 months was 0 degrees of extension and 4 degrees of flexion. All mean objective data, including the anterior drawer, Lachman, and pivot shift, demonstrated improvement at final followup. Cybex testing revealed improvement in relative quadriceps strength from 88% to 99%. The KT-1000 Arthrometer showed improvement in the injured-normal knee difference score throughout the follow-up period. Of importance is that while final objective data was improved over initial data, an early nonprogressive shift toward loosening was indicated by worsening of the drawer, Lachman, pivot shift, and KT-1000 scores. This shift may be attributed to resorption of interposed soft tissue, creep, or loosening of the graft. Subjective scores remained stable after improving. Complications included four ruptures, four chronic sterile effusions with partial attenuation, one infection, and one symptomatic loose body.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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PURPOSE: To evaluate whether the inheritance of the apolipoprotein E (ApoE) epsilon4 allele is a risk factor for nonlesional temporal lobe epilepsy (TLE), and to determine whether the newly described -491 A/T ApoE polymorphism may independently affect the risk of nonlesional TLE. METHODS: The study group consisted of 63 patients (35 women and 28 men; age at onset of epilepsy, 30.6 +/- 19.6 years; mean (+/-SD). All of them had received a diagnosis of nonlesional TLE after a detailed clinical, electroencephalographic, and brain magnetic resonance investigation. The ApoE polymorphisms were determined from blood samples by standard methods. The molecular study also was performed in 220 age- and sex-matched normal individuals. RESULTS: There were no differences between TLE patients and controls in either allelic or genotypic frequencies of the ApoE and -491A/T polymorphisms. Moreover, no effect of ApoE or -491A/T polymorphisms was found on the age at onset and severity of epilepsy. CONCLUSIONS: The allelic and genotypic frequencies of ApoE polymorphisms in Italian patients with nonlesional TLE are comparable to control values, indicating that ApoE polymorphisms are not a significant genetic risk factor for the occurrence of nonlesional TLE.  相似文献   
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Educational mobility is familiar to diploma and associate degree faculty and is emphasized in the Institute of Medicine Report, The Future of Nursing. Utilizing this premise, a team of nurse educators and administrators implemented the principles of organizational redesign, change process, and project planning to facilitate a transformation from a hospital-based diploma program to a university bachelor of science in nursing program. The process described truly exemplifies the fact that “it does take a village” to create success.  相似文献   
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Decreased heart rate variability (HRV) is a risk factor for cardiovascular mortality. Elevated plasma free fatty acid (FFA) levels decrease HRV in healthy subjects. Thus, we investigated the effect of changes in plasma FFA levels on HRV, in non-insulin-dependent diabetes (NIDDM) patients. Thirty NIDDM patients free from diabetic neuropathy volunteered for a study made by two phases. In study A, changes in HRV along a 10% lipid emulsion infusion + heparin (n = 15) or saline infusion (control study; n = 15) were investigated. In study B, all patients (n = 30) underwent further determination of HRV after 3 months of improved metabolic control achieved by intensified insulin treatment. In study A, lipid emulsion infusion increased plasma FFA (P < 0.001) and catecholamine concentrations (P < 0.005), mean arterial blood pressure (P < 0.005), low frequency/high frequency (LF/HF) ratio (P < 0.001). Delta plasma FFA levels correlated with delta LF/HF ratio (r = 0.57; P < 0.02). Along with saline infusion, metabolic and cardiovascular parameters remained unchanged throughout the test. In study B, improved metabolic control lowered fasting plasma glucose (P < 0.005), FFA (P < 0.001), norepinephrine (P < 0.02), epinephrine (P < 0.04), and glycosylated hemoglobin levels (P < 0.001), mean arterial blood pressure(P < 0.05), and LF/HF ratio (P < 0.001). Again percent decline in plasma FFA correlated with the percent change in LF/HF ratio (r = 0.72; P < 0.001). In a multivariate analysis, percent changes in LF/HF ratio were associated with percent changes in plasma FFA independently of gender and percent changes in body mass index, waist/hip ratio, plasma norepinephrine, epinephrine, glycosylated hemoglobin, and daily insulin therapy. Our study demonstrates that changes in plasma FFA levels may have a parallel effect on cardiac sympathetic/parasympathetic nervous system balance in NIDDM patients.  相似文献   
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Copper-zinc superoxide dismutase-1 (SOD1) is the second most common mutated gene in amyotrophic lateral sclerosis (ALS). To date more than 150 missense mutations of SOD1 have been reported. The objective of this study was to describe a novel SOD1 mutation and its phenotypic expression. We describe a 74-year-old Caucasian man who began to complain of progressive weakness and atrophy of the right hand and over 10 months developed a severe tetraparesis, with atrophies of upper and lower limbs and neck muscles, dysphagia, and dyspnea that led to percutaneous endoscopic gastrostomy and tracheotomy. A diagnosis of ALS was made. Genetic analysis identified a heterozygous mutation in exon 4 of SOD1 that results in the amino acid substitution from arginine to cysteine at position 115 (p.R115C). We identified a novel pathogenic SOD1 mutation in a patient with a very rapid disease progression and aggressive phenotype providing additional information on the wide range of SOD1 mutations in apparently sporadic ALS and confirming the possibility of a strong genotype-phenotype correlation for distinct SOD1 mutations.  相似文献   
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Pontin is a highly conserved DNA helicase/ATPase which is a component of several macromolecular complexes with functions that include DNA repair, telomere maintenance and tumor suppression. While Pontin is known to be essential in yeast, fruit flies and frogs, its physiological role in mammalian organisms remains to be determined. We here find that Pontin is highly expressed in embryonic stem cells and hematopoietic tissues. Through germline inactivation of Ruvbl1, the gene encoding Pontin, we found it to be essential for early embryogenesis, as Ruvbl1 null embryos could not be recovered beyond the blastocyst stage where proliferation of the pluripotent inner cell mass was impaired. Conditional ablation of Ruvbl1 in hematopoietic tissues led to bone marrow failure. Competitive repopulation experiments showed that this included the loss of hematopoietic stem cells through apopotosis. Pontin is, therefore, essential for the function of both embryonic pluripotent cells and adult hematopoietic stem cells.  相似文献   
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