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41.
Urinary 1-microglobulin (U-A1M) was measured in healthy term infants on days 1, 4, 7, 14, 28, 90 and 180 of life. U-A1M was high until day 14 and declined thereafter. It was significantly correlated with urinary 2-microglobulin (U-B2M) throughout the study, but not with serum A1M on days 1 or 7. Similar to U-B2M, U-A1M in the clinically stable term infants with intrauterine growth retardation (n=4–7) was not elevated on days 1–7. In the sick infants who needed immediate resuscitatio at birth (n=4–8), U-A1M as well as U-B2M was high on days 1–7 and then decreased to normal levels, suggesting that U-A1M can be used as a sensitive marker of acute proximal tubular damage and its recovery. These observations indicate that U-A1M is a useful index of proximal tubular function in early infancy.  相似文献   
42.
The chemical and radio toxicity of 125-5-iodo-2-deoxyuridine (125IUDR) on 870127T human lung cancer (HLC) cells grown in tissue cultures and the quantitative analysis of the distribution and fate of 125IUDR-labeled 870127T HLC cells in nude mice were evaluated. After 870127T HLC cells were plated and 125IUDR was added to the dishes at levels ranging from 0.1 µCi/ml to 5.0 µCi/ml of media, the growth rate of the cells for 24h was similar to that of non-labeled cells. Nude mice were given intravenous injections of 125IUDR labeled 870127T HLC cells and killed at various intervals ranging from 5 min to 24 h after injection. Organs were collected, processed, and monitored. The lung contained most of the tumor cells at all intervals and the number of tumor cells in the lung decreased gradually post-injection. The tumor cells died rapidly, and only about 1.5% of all cell survived after 24 h post-injection. This study confirmed that very few surviving tumor cells are needed to cause metastasis.  相似文献   
43.
To elucidate the necessity of pyloroplasty for the gastric tube through the posterior mediastinum in esophageal surgery, gastric emptying and duodenogastric reflux (DGR) were evaluated in 16 cases undergoing an anterior pylorectomy (group P) and in 16 cases treated by the finger bougie method (group F). First, the obstruction and reflux symptoms were examined based on a patient questionnaire using a brief scoring system. The median value of the symptom score showed the patients in P to have more symptoms than those in F; however, the difference was not significant (8.0 vs 6.0). Secondly, the swallowed Tc O4 (85 MBq) was counted using a gamma camera at three sites on the sternal bone in the upright position based on a gastric transit scintigram. Both the descending time of the RI peak and the clearance rates were similar between the two groups. Thirdly, intragastric 24-h pH monitoring was carried out. Antimony pH sensors were anchored 5 and 15 cm below the esophagogastrostomy. We could not find any difference between the two groups in both the % time pH>4 and %time pH>7. These findings thus revealed no big difference between groups P and F. The finger bougie method to drain the vagotomized posterior mediastinal stomach was found to achieve results similar to conventional pyloroplasty, while it was also simpler and safer.  相似文献   
44.
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology of TAWH.  相似文献   
45.
The ability to artificially express a particular receptor protein in the postsynaptic sites of neurons in the central nervous system (CNS) would be useful for the study of synaptic function of cloned receptor genes as well as for gene therapy of neurological disorders caused by dysfunction of postsynaptic receptors. In this study, we aimed to express the cDNA of unedited GluR2 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptor that forms inwardly rectifying and Ca2+-permeable channel in CNS neurons by using adenoviral-mediated gene transfer. For this purpose, we have constructed a recombinant adenovirus bearing an expression-switching unit, where the unedited GluR2 cDNA can be activated by the Cre recombinase-mediated excisional deletion of a stuffer DNA interposed between the promotor and the coding region. When PC12 cells were infected with this recombinant adenovirus together with an adenovirus expressing Cre recombinase, the inwardly rectifying and Ca2+-permeable AMPA receptor channels were expressed in nearly 100% of infected cells. Two days after co-infection of cultured rat hippocampal neurons with these adenoviruses, fast excitatory neurotransmission in the glutamatergic synapse was mediated predominantly by the inwardly rectifying and Ca2+-permeable AMPA receptor channels. This indicates that the native AMPA receptors in the postsynaptic sites of the glutamatergic synapse are replaced rapidly with recombinant receptors newly produced by the viral-mediated gene transfer.  相似文献   
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47.
Abstract Background: Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years.  相似文献   
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To explore more fully the relationship between neuronal death and neurofibrillary degeneration, unaffected neurons, intracellular neurofibrillary tangles (i-NFT) and extracellular NFT (e-NFT) in 22 patients with late-onset sporadic Alzheimer's disease (AD) were morphometrically evaluated in eight subdivisions of the hippocampal cortex, using the Gallyas hematoxylin-eosin stain. The subdivisions examined included CA4, CA3, CA2, CA1 (CA: cornu ammonis), prosubiculum (PRO), subiculum and presubiculum (PRE), parasubiculum (PARA) and the entorhinal cortex (ENT). The unaffected neuron density was significantly lower and both i-NFT and e-NFT densities were significantly higher in subdivisions other than CA4 and CA3 in AD patients compared with those in the aged controls. Unaffected neuron density was significantly, inversely correlated with e-NFT density and with total NFT density in all subdivisions except for PRE in AD patients. Especially in CA2, CA1, PRO and ENT, there were strong correlations between the neuron density and these NFT densities. Both unaffected neuron and e-NFT densities in CA1 and ENT were significantly correlated with the disease duration. The i/e-NFT ratio, an index of the degree and/or rate of progress of neuronal death via neurofibrillary degeneration, showed the lowest value in ENT in AD patients. The findings suggest that neuronal death via neurofibrillary degeneration starts earliest and/or most rapidly progresses in ENT. Furthermore, the i/e-NFT ratios in both ENT and CA1 were significantly correlated with the disease duration, suggesting that the neuronal death pattern in the two subdivisions parallels disease progression.  相似文献   
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