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991.
ABSTRACT: Background: Current practice guidelines recommend active management of the third stage of labor. We compared practices of three maternity care provider disciplines in management of third‐stage labor and the justifications for their approach. Methods: This study is a cross‐sectional survey of maternity practitioners in usual practice settings in British Columbia. All 199 obstetricians, all 82 midwives, and a random sample of family physicians practicing intrapartum maternity care (one‐third, or 346) were surveyed The three main outcome measures by discipline were the method preferred in managing third‐stage labor, the reasons given for the chosen method, and views on the appropriateness of the current third‐stage labor guideline. Results: The overall response rate was 57.8 percent. Response rates indicating that the participants were “aware of guideline” were the following: obstetricians, 85.3 percent; family physicians, 53.7 percent; and midwives, 97.8 percent. Response rates indicating that the participants “agreed with guideline” were the following: obstetricians, 95.2 percent; family physicians, 97.6 percent; and midwives, 51.2 percent. Response rates indicating that “oxytocin should be given with anterior shoulder” were the following: obstetricians, 71.1 percent; family physicians, 68.3 percent; and midwives, 26.7 percent. Response rates indicating that “routine active management of third stage of labor should be the norm” were the following: obstetricians, 79.2 percent; family physicians, 60.2 percent; and midwives, 17 percent. All results were statistically significant (p < 0.01). Conclusions: A major difference was found between physicians and midwives in the management of third‐stage labor. Physicians routinely implemented active management of the third stage of labor; midwives preferred expectant approaches, principally based on women’s preference. Provincial data did not show differences in postpartum hemorrhage or transfusion rates by practitioner type. (BIRTH 35:3 September 2008)  相似文献   
992.
Community-acquired pneumonia generally has a benign course when treated, but can be complicated by pleural effusion, empyema, lung abscesses, necrotizing pneumonia or pneumatoceles. Pneumatoceles can cause cardiorespiratory compromise requiring urgent intervention. A child with a severe necrotizing pneumonia, as well as a large early pneumatocele complicating mechanical ventilation, is presented. While pneumonectomy resulted in transient improvement, the course was further complicated by multiple late occurring pneumatoceles that ultimately led to the patient’s death.  相似文献   
993.
Catla catla fingerlings were reared in freshwater and exposed to 15.5 ppm concentration of lead for 60 days. The morphological changes on the gill of the C. catla fingerlings due to lead intoxication and the effect of DMSA (meso 2,3-dimercaptosuccinic acid) on the affected tissues were observed using Scanning Electron Microscope. It has been found that the lead treated gill tissues showed certain marked changes, such as cell hypertrophy, alteration in the lamellar surfaces, epithelial hyperplasia and the fusion of adjacent lamellae. The antidote DMSA treatment reduces the toxic effects and helps the recovery of gill tissue and its return to the level of the control/normal.  相似文献   
994.
995.
Stress fractures are considered a relatively common athletic injury. Some authors also feel this disorder may be overlooked in many nonathletic patients. Three cases of stress fractures are presented. All had classical clinical pictures; however, two were athletes and one was not. The athletes' stress fractures were suspected early in the disease evolution, confirmed with a bone scan and proper care instituted to prevent extended morbidity. The nonathlete's case was misdiagnosed by another practitioner and allowed to progress to the level of a true fracture. Extended morbidity followed this case. The infrequent report of nonathlete stress fractures in the literature may have played a major role in this oversight. Stress fractures do occur in athletes and nonathletes. The history is the key to making an early diagnosis. Scintigraphy (bone scan) or plain films may be used to confirm the diagnosis and rule out other disorders.  相似文献   
996.
Although there is a high degree of homology in the M2 transmembrane segments of alpha1 and beta1 subunits, subunit-specific effects were observed in alpha1beta1 GABA(A) receptors expressed in Spodoptera frugipedra (Sf9) cells when the conserved 13' threonine residue in the M2 transmembrane region was mutated to alanine. When threonine 263 (13') was mutated to alanine in the beta1 subunit, high-affinity muscimol binding and the response to GABA were abolished. This did not occur when the threonine 263 (13') was mutated to alanine in the alpha1 subunit, but the rate of desensitisation increased and the effect of bicuculline, a competitive inhibitor, was reduced. The results show differential effects of subunits on receptor function and support a role for M2 in desensitisation.  相似文献   
997.
The accurate measurement of pupillary defects is of value in following patients with optic nerve disease, as well as for comparing patients, groups, diseases and tests. The numerous problems encountered in measuring the pupil are considered, and a measurement technique using neutral density filters with the swinging light test is described and illustrated.  相似文献   
998.
Our aim was to assess brain myo-inositol/creatine plus phosphocreatine (Cr) in the first week in term infants with neonatal encephalopathy using localized short echo time proton magnetic resonance spectroscopy and to relate this to measures of brain injury, specifically lactate/Cr in the first week, basal ganglia changes on magnetic resonance imaging (MRI), and neurodevelopmental outcome at 1 y. Fourteen term infants with neonatal encephalopathy of gestational age (mean +/- SD) 39.6 +/- 1.6 wk, birth weight 3270 +/- 490 g, underwent MRI and magnetic resonance spectroscopy at 3.5 +/- 2.1 d. Five infants were entered in a pilot study of treatment with moderate whole-body hypothermia for neonatal encephalopathy; two were being cooled at the time of the scan. T(1)- and T(2)-weighted transverse magnetic resonance images were graded as normal or abnormal according to the presence or absence of the normal signal intensity of the posterior limb of the internal capsule and signal intensity changes in the basal ganglia. Localized proton magnetic resonance spectroscopy data were obtained from an 8-cm(3) voxel in the basal ganglia using echo times of 40 and 270 ms, and the peak area ratios of myo-inositol/Cr and lactate/Cr were measured. Outcome was scored using Griffith's development scales and neurodevelopmental examination at 1 y. MRI and outcome were normal in six infants and abnormal in eight. myo-Inositol/Cr and lactate/Cr were higher in infants with abnormal MRI and outcome (p < 0.01, p < 0.01, respectively). myo-Inositol/Cr and lactate/Cr were correlated (p < 0.01) and were both correlated to the Griffith's developmental scales (p < 0.01, p < 0.01, respectively). In conclusion, these preliminary data suggest that early increases in brain basal ganglia myo-inositol/Cr in infants with neonatal encephalopathy are associated with increased lactate/Cr, MRI changes of severe injury, and a poor neurodevelopmental outcome at 1 y.  相似文献   
999.
1000.
Gamete competition models were used to explore the relationships between 13 ACE gene polymorphisms and plasma ACE concentration in a set of Nigerian families. Several markers in the 5′ and 3′ regions of the gene were significantly associated with ACE concentration (P < 10‐4). Multi‐locus genotypes comprising different combinations of markers from the 5′ UTR and the 3′ region of the gene were also analysed; in addition to G2350A, in the 3′ region, two markers from the 5′ UTR (A‐5466C and A‐240T) were found to be associated with ACE concentration. These results are consistent with reports that have suggested the presence of at least two ACE‐linked QTLs, and demonstrate the utility of gamete competition models in the exploratory investigation of the relationship between a quantitative trait and multiple variants in a small genomic region.  相似文献   
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