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51.
1. A total of 360 Japanese quail of 4 commercial meat-type lines and two diet treatments (260 and 216 g/kg or 238 and 195 g/kg of crude protein (CP) in the starter and grower diet, respectively) were used. 2. The positive effect of a high CP diet on body weight was significant only for the first 4 weeks after hatching. 3. The mean age at inflection point of the growth curve (t+) across lines and sexes was 1.4 d (0.6 to 2.8 d within line/sex groups) earlier for quail fed on a high CP diet than in quail receiving a low CP diet. The inflection (y+) and asymptotic (A) weights were similar under both dietary protein concentrations. Nevertheless, the shape of the growth curve, characterised by the ratio y+/A and parameter of the maturing rate k, was significantly influenced by diet. 4. A higher food intake and less efficient food conversion were found for quail fed on a high CP diet in the period from 15 to 28 d of age. 5. The fattening traits such as body weight, cumulative food intake and food conversion, were not affected by dietary CP content at the age of 5 weeks. 6. The effects of line on body weight, food intake and food conversion are discussed.  相似文献   
52.
Two classes of glial cells are found in the embryonic Drosophila CNS, midline glial cells and lateral glial cells. Midline glial development is triggered by EGF-receptor signalling, whereas lateral glial development is controlled by the gcm gene. Subsequent glial cell differentiation depends partly on the pointed gene. Here we describe a novel component required for all CNS glia development. The tramtrack gene encodes two zinc-finger proteins, one of which, ttkp69, is expressed in all non-neuronal CNS cells. We show that ttkp69 is downstream of gcm and can repress neuronal differentiation. Double mutant analysis and coexpression experiments indicate that glial cell differentiation may depend on a dual process, requiring the activation of glial differentiation by pointed and the concomitant repression of neuronal development by tramtrack.  相似文献   
53.
Gamma delta T-Cells represent a minor subpopulation of T-lymphocytes in man and their role in normal and diseased human skin is unknown. This article is a comprehensive review of T-lymphocytes bearing the gamma delta T-cell receptor in normal and pathological human skin. Firstly, we have documented the occurrence of gamma delta T-cells in normal skin and in a range of reactive and malignant skin conditions. We have then discussed the experimental findings regarding the repertoire used by gamma delta T-cells in normal human skin and in cutaneous disorders with an increased percentage of gamma delta T-cells.  相似文献   
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There are evidence indicating that endoscopic retrograde cholangiopancreatography with sphincterotomy (ERCP+S) reduces the rate of complications in patients with severe acute biliary pancreatitis (ABP). The aim of this study was to analyze our experience in the treatment of severe ABP with ERCP+S and compare the evolution of the patients treated early (3 days or less following admission) with those treated late (after the 3rd day). A retrospective review of the clinical histories of the 16 patients with severe ABP treated with ERCP+S over the last two years is presented, analyzing their clinical features on admission and evolution. Biliary stones or biliary sludge was observed in 11 cases (69%). Nine patients had undergone early, and 7 late, ERCP+S. The patients of the latter group presented a greater number of complications during evolution than the former group (43% vs 0%; p = 0.025). The mortality of the patients of the late ERCP+S was also greater although without statistical significance (28.6% vs 0%; p = 0.15). No complication secondary to ERCP+S was detected. These findings confirm the fact that ERCP+S performed early in severe ABP significantly reduces the number of complications and is associated with a lower mortality.  相似文献   
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The aim of study was the evaluation of periodontal pockets microflora in patients with advanced periodontitis. From each subject 16-20 samples were taken using paper points. Pooled sample after 60 s. mixing was serially diluted in reduced BHI. For total cell counts and for the isolation of black pigmented anaerobes Brucella agar supplemented with 5% sheep blood, hemin, menadione, with and without Kanamycin-Vancomycin mixture and BM agar plates were used. For isolation of A. actinomycetemcomitans TSBV agar plates were used. Cultures were incubated in anaerobic chamber at 37 degrees C for 7 days and TSBV agar plates in an atmosphere of 95% air-5% CO2 at 37 degrees C for 5 days. Microorganisms were identified by Gram staining, colony morphology, fluorescence in UV-light, haemagglutination of 3% sheep erythrocytes, fermentation of sugars, production of indole, urease (API 20A), specific enzymes (Rapid ID 32A). Twenty seven subjects with clinically recognized periodontitis were examined. Microorganisms important in periodontitis were isolated from periodontal pockets of almost all examined subjects. The number of bacteria obtained from the sample of one patient ranged from 1 x 10(4) CFU/ml to 3,6 x 10(6) CFU/ml. Porphyromonas gingivalis was identified in the samples taken from 17 patients, Prevotella intermedia-19, Actinobacillus actinomycetemcomitans -11, Fusobacterium nucleatum-9, Peptostreptococcus spp.-22.  相似文献   
59.
Morgagni hernias are the least common form of diaphragmatic hernias. Although they are congenital, most of them are not diagnosed until later in life. The indication for surgery is based on the patient's symptoms or on the radiological evidence of incarcerated tissue, and until quite recently involved a laparotomy or thoracotomy. Laparoscopy not only permits the suspected diagnosis to be confirmed--which is otherwise often difficult--but also makes it possible to close the hernia site by suturing. For improved security, the hernia site is augmented by fixing in place a non-absorbable mesh. The operative technique employed is described.  相似文献   
60.
The modulatory role of locally produced cyclooxygenase products and endothelium-derived nitric oxide in controlling vascular tone was investigated in bovine intra-mammary artery. Vascular reactivity initiated by vasoactive compounds, endothelin-1 (ET-1), bradykinin (BK), and substance P (SP) was measured isometrically in an isolated tissue bath. The effects of a cyclooxygenase inhibitor, indomethacin (10(-5) M) and an inhibitor of nitric oxide production, N omega-Nitro L-Arginine (L-NNA: 3 x 10(-4) M) were determined during agonist-mediated responses. Indomethacin alone markedly enhanced vascular contraction produced by ET-1, while L-NNA did not. Inhibition of endothelium-derived nitric oxide synthesis by L-NNA, however, significantly attenuated BK- and SP-induced vascular relaxations, whereas indomethacin had slight influence. The potentiation between indomethacin and L-NNA in regulating vasomotor tone was not observed in this vascular bed. Thus, it appeared that both the cyclooxygenase and endothelium-derived nitric oxide pathways participated in modifying vascular reactivity. Domination of one pathway over the other depended upon the agonist used to stimulate vascular tissue.  相似文献   
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