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61.
62.
Cardiac morphogenesis and function are known to depend on both aerobic and anaerobic energy-producing pathways. However, the relative contribution of mitochondrial oxidation and glycogenolysis, as well as the determining factors of oxygen demand in the distinct chambers of the embryonic heart, remains to be investigated. Spontaneously beating hearts isolated from stage 11, 20, and 24HH chick embryos were maintained in vitro under controlled metabolic conditions. O(2) uptake and glycogenolytic rate were determined in atrium, ventricle, and conotruncus in the absence or presence of glucose. Oxidative capacity ranged from 0.2 to 0.5 nmol O(2)/(h.microg protein), did not depend on exogenous glucose, and was the highest in atria at stage 20HH. However, the highest reserves of oxidative capacity, assessed by mitochondrial uncoupling, were found at the youngest stage and in conotruncus, representing 75 to 130% of the control values. At stage 24HH, glycogenolysis in glucose-free medium was 0.22, 0.17, and 0.04 nmol glucose U(h.microg protein) in atrium, ventricle, and conotruncus, respectively. Mechanical loading of the ventricle increased its oxidative capacity by 62% without altering glycogenolysis or lactate production. Blockade of glycolysis by iodoacetate suppressed lactate production but modified neither O(2) nor glycogen consumption in substrate-free medium. These findings indicate that atrium is the cardiac chamber that best utilizes its oxidative and glycogenolytic capacities and that ventricular wall stretch represents an early and major determinant of the O(2) uptake. Moreover, the fact that O(2) and glycogen consumptions were not affected by inhibition of glyceraldehyde-3-phosphate dehydrogenase provides indirect evidence for an active glycerol-phosphate shuttle in the embryonic cardiomyocytes. 相似文献
63.
Florence Rochat Christine Cherbut Denis Barclay Giuseppe Puccio Angela Fazzolari-Nesci Dominik Grathwohl Ferdinand Haschke 《Nutrition Research》2007,27(12):735-740
To compare the effects of a whey-predominant infant formula and breast milk on the gut microbiota, growth, and tolerance of infants, we conducted an open, prospective, parallel-group study in healthy newborn infants. A total of 60 infants were enrolled, and 55 completed the study. Of the 55 infants, 21 were breast-fed and 34 were fed a whey-predominant study formula that had low phosphate concentration (31 mg/100 kcal), was reduced in protein (1.8 g/100 kcal or 0.43 g/kJ), had lactose as the sole carbohydrate source, and had an amino acid profile and buffering capacity similar to that of human milk. At 30 and 60 days of age, fecal bacterial counts were determined using fluorescence in situ hybridization and culture plating, and growth and digestive tolerance were evaluated. There were no differences in fecal bacterial counts between formula-fed and breast-fed infants at either 30 or 60 days. Fecal counts of bifidobacteria, lactobacilli, clostridia, enterococci, and Enterobacteriacea were similar in the 2 groups using both bacterial enumeration methods. Growth and digestive tolerance were also similar in the 2 groups. Thus, this whey-predominant infant formula is safe and well tolerated, and it affects infants' microbiota in a similar manner as observed with breast milk. 相似文献
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66.
M J Rosenberg R W Rochat J Akbar P Gould A R Khan A Measham S Jabeen 《International journal of gynaecology and obstetrics》1982,20(4):283-291
Although surgical sterilization in Bangladesh is common and has been designated as the primary means of helping the country slow its population growth, no reliable information exists regarding the procedure's safety. To define the types and rates of medical complications associated with sterilization, we followed 5042 women and 264 men undergoing sterilization. The problems that increased most markedly after the procedure compared with before included painful urination, shaking chills, fever for at least 2 days, and frequent urination. Most of the postoperative problems could be predicted by the presence of the same problem before the operation. Factor analysis of complaints in those persons who did not have a specific preoperative complaint showed that complaints clustered into three groups: urinary tract symptoms (urinary urgency and frequency), skin problems (bleeding from the incision, sore with pus, and stitches or skin breaking open), and general complaints (weakness and dizziness). The patient's sex, the sponsor and patient load of the sterilization center, and the dose of sedatives administered to women were significantly associated with specific postoperative complaints. Five women died during the study, resulting in a death-to-case rate of 9.9/10,000 procedures tubectomies; four deaths were due to respiratory arrest caused by oversedation. 相似文献
67.
D A Grimes H B Peterson M J Rosenberg J I Fishburne R W Rochat A R Khan R Islam 《International journal of gynaecology and obstetrics》1982,20(2):149-154
From January 1, 1979, to March 31, 1980, 20 sterilization-attributable deaths were identified in Dacca and Rajshahi Divisions, Bangladesh. The leading cause of death from tubectomy was anesthesia overdose and from vasectomy, scrotal infection. Overall. The sterilization-attributable death-to-case rate was 21.3 deaths/100,000 procedures. The health impact of contraceptive sterilization is highly favorable: for each 100,000 tubectomies performed, the cost in lives (19) is offset by approximately 1015 maternal deaths averted. 相似文献
68.
1背景 育龄妇女常见慢性下腹痛,可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元(Mathias 1996)。英国全国数据库的一般性诊治资料显示,慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似(Zondervan 1999)。 相似文献
69.
RW Parks FRCS MAR Clarke MRCPath B Cranley MD FRCS 《International journal of clinical practice》1997,51(6):414-415
Adenomyoepithelioma is a rare disorder characterised by simultaneous proliferation of ductal epithelium and myoepithelial cells. It is more common in salivary glands or skin, and only rarely found in breast tissue. Adenomyoepithelioma of the breast was first described in 1970 by Hamperl.1 Since then, approximately 55 cases have been described in the literature; the largest review, by Tavassoli in 1991, reported 27 of these cases.2 Because of the small number of cases reported, the natural history of adenomyoepithelioma of the breast remains uncertain. We report a further case which was treated by local excision, and follow-up for two years has revealed no evidence of local recurrence or metastatic spread. 相似文献
70.
To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens. 相似文献