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81.
OBJECTIVES: The neurodevelopmental progress of newborn term infants is checked routinely at around 6 weeks of postnatal age. The maturation of neurological signs in this age range however has not been systematically studied and normative data are not available. The aim of this study was to document any changes in posture, tone, reflexes, behaviour and movements in low-risk full-term infants between 3 and 10 weeks of postnatal age. STUDY DESIGN: We performed a structured neurological examination previously standardised in full-term newborns in the first 48 h after birth. In the current study, a total of 76 examinations were performed between 3 and 10 weeks of age in low-risk full-term infants. RESULTS: The results of the examinations were divided according to postnatal age. In most items, the scores changed with time, with a definite shift in their distribution occurring around 6 weeks. At this age, a reduction in flexor tone of the limbs was observed, together with an increase in active neck tone. Visual orientation in contrast had already improved by 3 weeks when all infants were able to follow a target in a full circle compared to newborns that are often only able to follow a target in an arc. CONCLUSIONS: Our results suggest that 6 weeks post-term birth is an important milestone for changes in neurological signs, particularly those related to muscle tone and posture, probably reflecting maturation of the nervous system. These findings provide important guidelines for the interpretation of the neurological examination performed at this age.  相似文献   
82.
The effects of the nitric oxide (NO) donor molsidomine on aged rats' cognition were evaluated in two different behavioral tasks: the step-through passive avoidance paradigm and the object recognition test. Post-training injection of molsidomine (at 4 but not at 2 mg/kg) significantly counteracted the performance deficits displayed by old rats in both the behavioral paradigms. These results support and extend prior findings about the implication of NO in learning and memory mechanisms. In addition, for the first time, a NO donor was found to antagonize age-related memory impairments, suggesting that the integrity of the NO-ergic system may be important in brain aging processes.  相似文献   
83.
OBJECTIVE: To evaluate retrospectively the prevalence of neuromuscular disorders in 83 newborns referred to a tertiary care center because of hypotonia and weakness and/or contractures, with a possible diagnosis of neuromuscular disorder. We also aimed to establish whether clinical signs could help to identify infants with neuromuscular disorders. STUDY DESIGN: Sixty-six of the 83 infants who fulfilled the inclusion criteria (79.5%) had an identifiable disorder, which was a neuromuscular disorder in 39 (46.9%). RESULTS: Absent or extremely reduced antigravity movements were mainly found in infants with neuromuscular disorders (sensitivity and specificity 97.4% and 75%), whereas partial range antigravity movements were more frequent in infants with other diagnosis. Contractures were mainly found in infants with peripheral nerve or muscle involvement but also were relatively frequent in infants with genetic or metabolic syndromes (sensitivity 69.2%, specificity 61.3%). Reduced fetal movements and abnormal liquor were frequent but not present consistently in infants with neuromuscular disorders (sensitivity 46.1% and 38.4%) and were found rarely in infants with other disorders (specificity 88.6% and 75.0%). CONCLUSIONS: Severe muscle weakness and contractures are the most reliable indicators of a neuromuscular disorder and should be carefully assessed in an infant with neonatal hypotonia.  相似文献   
84.
Spinal muscular atrophy (SMA) is caused by insufficient levels of survival motor neuron (SMN) protein. Recently, we found that sodium 4-phenylbutyrate (PB), a well-tolerated FDA approved drug, enhances SMN gene expression in vitro. We provide here the first evidence that oral administration of PB (triButyrate significantly increases SMN expression in leukocytes of SMA patients. This finding provides a strong rationale to further investigate the effects of PB as also supported by preliminary clinical data.  相似文献   
85.
The aim of this retrospective study was to evaluate the use of digital videofluorography in the preoperative and postoperative management of esophageal achalasia surgical treatment. From 1990 to 2004, 25 patients with achalasia, diagnosed by digital videofluorography and confirmed by motility studies and endoscopy, underwent surgery. All patients underwent digital videofluorography at 1, 6 and 12 months in order to evaluate the completeness of the myotomy and the efficacy of the antireflux procedures. At postoperative videofluorography esophageal transit time was decreased in all patients (100%); esophageal motor activity was unchanged in 23 (92%), and modified in two patients (8%) with onset of peristaltic-like motor activity; 8 patients (35%) presented decreased preoperative dilatation; all patients had a WST negative for post-myotomy reflux. On the basis of our experience and the advantages of the procedure we suggest videofluorography as a first-approach diagnostic examination useful for surgical indications and postoperative follow-up in achalasic patients.  相似文献   
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BACKGROUND: The aim of the study was to determine whether left ventricular mass regression is influenced by valve size after the implantation of a Carpentier-Edwards Perimount (CEP) pericardial bioprosthesis for pure aortic stenosis. METHODS: Patients receiving 19-mm, 21-mm, and 23-mm CEP aortic valves underwent echocardiography preoperatively and at least 1 year after surgery (mean, 2.3 +/- 1 years) and the echocardiograms were compared within and between groups. RESULTS: The study involved a total of 88 patients: 34 receiving 19-mm CEPs, 29 receiving 21-mm CEPs, and 25 receiving 23-mm CEPs. The mean postoperative prosthetic gradients were respectively 20.6 +/- 6.6 mm Hg, 17.9 +/- 5.8 mm Hg, and 13.2 +/- 4.1 mm Hg (p = 0.0001); the mean postoperative valve areas were respectively 1.24 +/- 0.16 cm(2), 1.45 +/- 0.2 cm(2), and 1.63 +/- 0.21 cm(2) (p = 0.0001). In comparison with the preoperative echocardiographic measurements absolute left ventricular mass significantly decreased by -54.1 +/- 48.8 g, -54.1 +/- 55.1 g, and -74.4 +/- 57.4 g respectively with no statistically significant between-group difference (analysis of variance) but ventricular septum and posterior wall thickness significantly decreased in each group (p < 0.05). CONCLUSIONS: The implantation of 19-mm, 21-mm, and 23-mm CEP aortic prostheses significantly reduces left ventricular mass without any size-related differences.  相似文献   
89.
Liver transplantation for malignancies still remains a controversial issue. There is concern for tumour recurrence, poor results and waste of organs, which in the sitting of organ shortage would penalize patients with non-malignant disease. Many centers worldwide perform liver transplantation (OLT) for hepatocellular (HCC) carcinoma associated with liver cirrhosis; the results in these cases are similar to those of patients transplanted for other indications. On the contrary are very few the centers that perform OLT for tumour other than HCC. This reflects that tumours other than HCC are less common and survival is poor compared to patients transplanted for non-malignant disease. Acceptable indications for OLT in case of tumours other than HCC are liver metastases from neuroendocrine tumours and epithelioid emangio-endothelioma. However should be kept in mind that OLT may offer the sole opportunity to cure the tumour and the underlying disease in some patients while providing meaningful palliation for others. At the present the overall experience with OLT for tumours other than HCC is still not significant and the results are discouraging. There is no evidence that OLT is beneficial for non-HCC tumours. Hopefully for the next future new adjuvant and neoadjuvant therapies combined with OLT would provide improved survival. Nevertheless, long-term survivors continue to be reported suggesting that OLT may be beneficial in individual selected cases with non-HCC tumour.  相似文献   
90.
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