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61.
Meconium aspiration syndrome creates mechanical airway obstruction with air trapping and atelectasis. Tracheobronchial saline lavage to dislodge meconium may precipitate respiratory distress, a wet lung appearance and respiratory failure. Two case studies are reported in which meconium aspiration resulted in mechanical obstruction and displacement of surfactant and in whom tracheobronchial saline lavage and artificial surfactant replacement reversed respiratory failure.  相似文献   
62.
Abstract This review discusses the pathogenesis of spina bifida and describes the microscopic appearance of the initial pathological features and their further development in the spinal cords. The embryos and fetuses were derived from pregnant mice given orally 60, 40 or 0 mg/kg of retinoic acid in olive oil on day 8 of gestation and killed one, two or 10 days later. Separation of the primary neural fold from the secondary neural tube was seen in 9- and 10-day-old embryos in which the caudal end of the neuroepithelium was disorganized and the posterior neuropore was open; underneath it, the secondary neural tissue was seen. At term, fetuses showed spina bifida, including myeloschisis, myelocele and diplo-myelia. The cord lesions were located between the third lumbar and second coccygeal levels. Thus, the differentiation and development of the spinal cord proceeds as in chick and human embryos, and the spinal cord caudal to the third lumbar level originates from both neuroepithelium and mesenchyme-like cells while that caudal to the third sacral level originates from mesenchyme-like cells only.  相似文献   
63.
Insulin was isolated from the pancreas of Chondrostean fish, the Russian sturgeon, Acipenser guldenstaedti, by acid-ethanol extraction followed by ion-exchange and reverse-phase high-performance liquid chromatographies. The amino acid sequence determined by automated Edman degradation is as follows: A-chain (21-amino-acid peptide), H-Gly-Ile-Val-Glu-Gln-Cys-Cys-His-Ser-Pro-Cys-Ser-Leu-Tyr-Asp-Leu-Glu-Asn-Tyr-Cys-Asn-OH; and B-chain (31-amino-acid peptide), H-Ala-Ala-Asn-Gln-His-Leu-Cys-Gly-Ser-His-Leu-Val-Glu-Ala-Leu-Tyr-Leu-Val-Cys-Gly-Glu-Arg-Gly-Phe-Phe-Tyr-Thr-Pro-Asn-Lys-Val-OH. The sturgeon insulin appears to be identical with one of two forms of paddlefish insulin and differs from the other form by a single substitution in the A-chain, Asp15: His15. The amino acid sequence of sturgeon insulin is more similar to the amino acid sequence of mammalian insulins than of other fish insulins. Sturgeon insulin showed parallel but weaker displacement than porcine insulin and pink salmon insulin in their respective radioimmunoassays and was less potent than porcine insulin in displacing radiolabeled porcine insulin bound to partially purified rat liver plasma membranes.  相似文献   
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A gene-counting method of maximum likelihood is elaborated for estimating gene frequencies in ABO and ABO-like systems (more generally phenogram m-[(m2-m+2)/2]-1). The present method has the advantages that the calculations in each iterative cycle is simple and that it is not necessary to invert the matrix, although more iterative cycles are needed than with the scoring method in order to attain to the same level of accuracy. Also, the problem of choosing appropriate trial values is discussed and several numeric examples are worked out.  相似文献   
68.
Background: Although perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) expression is strongly associated with ulcerative colitis, its relationship with the occurrence of pouchitis after restorative proctocolectomy is uncertain. Methods: Serum p-ANCA was assayed using both indirect immunofluorescence and enzyme-linked immunosorbent assay (ELISA) in 49 patients, of whom 25 had, and 24 had not, developed pouchitis. Control sera were obtained from 15 healthy volunteers. Results: By means of indirect immunofluorescence, p-ANCA was detected in 45.8% of patients without and in 48% with pouchitis (NS). Twenty-three (46.9%) of the 49 colitis patients were p-ANCA-positive, compared with none of the 15 controls (P < 0.01). By means of ELISA, p-ANCA positivity was present in 50% of patients without and in 68% with pouchitis (NS). Conclusion: Whereas p-ANCA was associated with ulcerative colitis as compared with normal individuals, it was not associated with pouchitis. Thus it is unlikely to be a suitable pre-operative marker to identify those patients who will develop pouchitis.  相似文献   
69.
Yasuda A, Uchida T, Nguyen LT, Kawazato H, Tanigawa M, Murakami K, Kishida T, Fujioka T, Moriyama M. A novel diagnostic monoclonal antibody specific for Helicobacter pylori CagA of East Asian type. APMIS 2009; 117: 893–9. Molecular biological and epidemiological studies have suggested that Helicobacter pylori producing East Asian CagA protein variant is more virulent than that producing Western CagA. In the present study, we developed and validated an enzyme‐linked immunosorbent assay (ELISA) using a monoclonal antibody specifically recognizing East Asian CagA‐positive H. pylori. A total of 32 H. pylori strains were tested and the data were subjected to receiver‐operator characteristic (ROC) curve analysis. The accuracy of the test, determined by calculating the area under the curve, was 0.96, which indicated a high level of accuracy. At the ROC optimized cutoff, the sensitivity and specificity of our ELISA method were 88.0% and 100%, respectively. The validated ELISA showed good performance in terms of sensitivity and specificity. These results suggest that this test is suitable for the diagnostic detection of East Asian CagA carrying strains. We also analyzed the localization of the CagA protein in H. pylori‐infected gastric mucosa with fluorescence immunohistochemistry, and found that CagA protein expression was up‐regulated by adhesion to epithelial cells.  相似文献   
70.
We applied a newly developed endoscopic resection technique for a rectal mucosal cancer of 4.2 cm. This method resulted in a curable treatment and provided precise information for histological examinations. This technique, using IT‐knife, may involve the risk of bleeding and perforation compared with conventional methods. Further improvements are needed to make this technique safer and more reliable for a standard endoscopic method for large colorectal tumors.  相似文献   
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