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71.
72.
Seventy five pregnancies where the presence of antepartum meconium was detected by transabdominal amniocentesis, were compared with 224 cases showing clear amniotic fluid (A.F.). The statistical differences were analized in terms of data of anamnesis, diseases complicating pregnancy, gestational age, fetal maturity diagnosis from the A.F. study, oxytocin test, labor characteristics, perinatal mortality and neurologic morbidity during the first nine months of life. The results suggest that the presence of antepartum meconium implies an increase in fetal risk, demanding an adequate analysis of the obstetric solutions, which is discussed.  相似文献   
73.
The PQ-interval was measured while resting supine before exercise testing, in the erect position on the bicycle before starting exercise, and resting supine after exercise in 68 men 6--8 weeks after acute myocardial infarction. During a 6-year follow-up period the death was non-sudden (greater than 1 hour) in 25 of these patients. In this group the PQ-time was significantly shorter (p less than 0.001) during somatomotor activation on the bicycle before exercise than resting supine. The same directional change (p less than 0.01) was seen in the sudden death (less than 1 hour) group (N = 21), but not in the patients who survived. PQ-time at supine rest before exercise testing, however, was significantly shorter (p less than 0.02) in surviving patients than in the non-sudden death group. The possible mechanisms of these, and of previously reported changes in the R-wave amplitudes and QT-times, are discussed.  相似文献   
74.
A new microfabrication process based on a xerographic process is described. A laser printer is used to selectively deposit toner on a polyester film, which is subsequently laminated against another polyester film. The toner layer binds the two polyester films and allows the blank regions to become channels for microfluidics. These software-outlined channels are approximately 6 microm deep. Approximately twice this depth is obtained by laminating two printed films. The resulting devices were not significantly damaged after 24 h of exposure to aqueous solutions of H3PO4, NaOH, methanol, acetonitrile, or sodium dodecyl sulfate. Electric tests with an impedance analyzer and microchannels filled with KCl solution demonstrated that (1) wide channels suffer from deformation of the top and bottom walls due to the lamination of the polyester films and (2) the toner walls are somewhat porous. Although these drawbacks limit the maximum width of a channel and the minimum distance between two channels, the process is an attractive option to other expensive, laborious, and time-consuming methods for microchannels fabrication. The process has been used to implement devices for electrospray tip and capillary electrophoresis with contactless conductivity detection.  相似文献   
75.
From March to November 2000, 170 samples of smoked fish and 182 samples of paté for sale in retail outlets and supermarkets in the nine provinces of Castilla and León (Spain) were analyzed for the prevalence of Listeria monocytogenes and other Listeria spp. L. monocytogenes was isolated from 38 (22.3%) of the 170 samples of smoked fish analyzed. Twenty of these positive samples contained L. monocytogenes at >100 CFU/g. Other Listeria spp., such as Listeria innocua (26 isolates), Listeria grayi (9), Listeria welshimeri (3), Listeria seeligeri (3), and Listeria ivanovii (2), were also detected. L. monocytogenes was isolated from 5.4% of the 182 samples of paté. Only 1 of the 10 positive samples harbored >100 L. monocytogenes CFU/g. Two other species of Listeria were observed in paté: L. innocua (12 isolates) and L. grayi (2).  相似文献   
76.
77.
An application of the z-transfer function method to predict temperature-time history of foodstuffs during chilling and cold storage is presented. This application is based on obtaining the temperature z-transfer function's coefficients by means of an experimental method. These coefficients are used to predict the temperature-time history of an homogeneous body and the results are compared with analytical and numerical solutions. This method is very useful when the geometry and/or boundary conditions are such that analytical or numerical solutions are difficult to obtain.  相似文献   
78.
Creatine kinase (CK) is an enzyme central to cellular high-energy phosphate metabolism in muscle. To characterize the physiological role of CK in respiratory muscle during dynamic contractions, we compared the force-velocity relationships, power, and work output characteristics of the diaphragm (Dia) from mice with combined myofibrillar and sarcomeric mitochondrial CK deficiency (CK[-/-]) with CK-sufficient controls (Ctl). Maximum velocity of shortening was significantly lower in CK[-/-] Dia (14.1 +/- 0.9 Lo/s, where Lo is optimal fiber length) compared with Ctl Dia (17.5 +/- 1.1 Lo/s) (P < 0.01). Maximum power was obtained at 0.4-0.5 tetanic force in both groups; absolute maximum power (2,293 +/- 138 W/m2) and work (201 +/- 9 J/m2) were lower in CK[-/-] Dia compared with Ctl Dia (2,744 +/- 146 W/m2 and 284 +/- 26 J/m2, respectively) (P < 0.05). The ability of CK[-/-] Dia to sustain shortening during repetitive isotonic activation (75 Hz, 330-ms duration repeated each second at 0.4 tetanic force load) was markedly impaired, with CK[-/-] Dia power and work declining to zero by 37 +/- 4 s, compared with 61 +/- 5 s in Ctl Dia. We conclude that combined myofibrillar and sarcomeric mitochondrial CK deficiency profoundly impairs Dia power and work output, underscoring the functional importance of CK during dynamic contractions in skeletal muscle.  相似文献   
79.
80.
In some jurisdictions, major disasters rarely occur. Those responsible for providing behavioral health services in these jurisdictions have less opportunity to accrue experience and understanding of disaster and less access to behavioral health funding support and guidance than is true elsewhere. This affects both preparedness and response. The state of Oregon, a lower profile state in terms of disaster experience, participated in the national TOPOFF 4 dirty bomb exercise. With necessity serving as the mother of invention, circumstances converged to reveal alternative strategies that may serve some lower profile jurisdictions more effectively than recommended standard practice and that appear to have economical benefit. Response strategy relied on recruitment and assignment of sufficient responders by collaborating among multiple existing trained resources rather than using a state or local public health volunteer registry. It also implemented just-in-time trainings and took advantage of other spontaneous teaching opportunities rather than relying on the efficacy of more costly traditional training models. Potential strategies for more economical preparedness and response activity and recommendations for addressing some current national shortcomings are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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