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81.
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One hundred and four preterm infants were studied during the first few months of life in the Special Care Baby Unit of Addenbrooke's Hospital, Cambridge, United Kingdom. Previously, it had been the daily practice within the Unit to give a 1 mg oral supplement of folate (in the form of pteroylglutamic acid), once the infants had commenced full enteral feeding. At least one blood sample was obtained from 70 infants before oral folate supplementation was started. In these, the plasma folate levels fell progressively from a median value of 45 g/l to a median of 12 g/l, by the 2nd–3rd week of life. Once started on the oral supplement, 83 of the infants provided at least one blood sample. The plasma folate level of these infants rose immediately to a median value of 300 g/l and a maximum of 1000 g/l. Within individuals, these plasma folate levels decreased progressively following the introduction of the supplement, despite continuing daily supplementation. In a typical baby this decrease appeared to be explained by an increase in body-size, i.e. dilution of the folate into a larger pool. The implications of this level of supplementation are discussed, and in the light of our observations we suggest that daily supplementation in the range, 0.05–0.2 mg folate may be preferable for well preterm infants.  相似文献   
83.
Thirteen hands in 11 patients with previous carpal tunnel releases were treated by microscopic internal neurolysis and palmaris brevis "turnover" flaps. All patients in the series had positive electrodiagnostic testing, dysesthetic wrist pain, and numbness in the median nerve distribution before operation. Average age was 41.9 years (range, 27 to 62 years). Ten were male and 3 were female. Range of follow-up after the procedure was from 1 to 1 1/2 years. All hands with abnormal preoperative two-point discriminations or Semmes-Weinstein measurements showed numerical improvement in their sensory parameters. Thenar strength and bulk improved at least one grade in all six cases of thenar atrophy. Mean grip strength was 15.2% greater than before operation. Key pinch increased 5.5% and pulp pinch 31.9%. Subjective assessment of improvement ranged from 25% to 100%. All patients returned to their former jobs or to vocational retaining except the oldest patient who is semiretired.  相似文献   
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The authors describe a family, of which 13 members had peripheral neuropathy manifesting as episodes of paralysies usually provoked by minor compression of nerve trunks. Nerve and muscle biopsies in two patients, demonstrated many thickenings of the myelin sheath ("tomacula"). Electron microscopy investigations are used as a basis for discussing the origin and place of this affection among other hereditary neuropathies.  相似文献   
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Primary closure with "minimal tension" of an inadequately debrided massive abdominal wall defect invariably results in further necrosis and dehiscence. Rotation flaps and prosthetic materials are potentially hazardous in severely traumatized and contaminated wounds. An alternate technique, utilizing an abdominal wall pack and porcine skin graft has been used in two patients with close-range shotgun blasts and one patient with postoperative necrotizing fascitis. The combination of a biological dressing and an abdominal wall pack, stinted by strategically placed retention sutures, controls infection, promotes healthy granulation tissue, and prevents bowel erosion with fistula formation.  相似文献   
88.
Subacute combined degeneration (SCD) of the spinal cord is known to present histopathologically degenerative lesions in the spinal cord, but few studies on the neuroradiological findings have so far been reported. We present the interest of initial and follow-up MR findings in three cases of SCD. In the three cases, a causal event precipitated the onset of neurological symptoms: general anesthesia for the first and the third one and folic acid treatment for the second one. Clinical evolution was favorable after specific treatment with nearly total recovery. The initial MR study disclosed lesions predominantly involving the posterior columns of the spinal cord: high intensity on T2 weighted image was seen in the initial MR study and disappeared three months after treatment in correlation with good recovery, but with a delay. The recognition of this MR pattern suggests that MRI may be used in conjunction with clinical assessment to confirm the diagnosis and to monitor the efficacity of treatment in SCD.  相似文献   
89.
Lucas C  Leclerc X  Pruvo JP  Leys D 《Revue neurologique》2000,156(12):1096-1105
Vertebral artery dissection is a frequent cause of ischemic stroke in young adults but time course of VA dissections remains poorly documented. Angiography was considered as the gold standard for the diagnosis. Recently, non-invasive methods have been developed such as helical CT and magnetic resonance angiography. The purpose of the study was to assess the reliability of a gadolinium-enhanced fast three dimensional (3D) magnetic resonance (MR) angiographic sequence to image vertebral arteries and to assess the long-term follow-up of vertebral artery (VA) dissections. Sixteen consecutive patients with 18 angiographically documented VA dissections were followed-up by gadolinium-enhanced 3D MR angiography and cervical T1-weighted MR imaging at a median delay of 22 months. Ten patients had MR imaging scan at the acute stage as well and nine had early follow-up angiography at a median delay of 3 months. MR angiography was evaluated in a consensus manner including image quality, presence of residual stenosis, luminal irregularities and occlusion. All patients clinically improved. Ten of 11 stenotic dissections returned to normality whereas one stenotic dissection progressed to occlusion. Two pseudoaneurysms detected on the initial angiography resolved spontaneously, one appeared only on a delayed MR angiographic scan and one was detected on early MR angiograms and finally resolved on a late one. Of the seven initially occluded VAs, five reopened with a hairline residual lumen in three. Contrast MR angiography is an interesting tool to assess the late course of VA dissections. Most lesions resolved spontaneously but persisting occlusion or pseudoaneurysm may be found in long term follow-up.  相似文献   
90.
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