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41.
Lee S. Clay Karen Criss Unjeria C. Jackson 《Journal of Midwifery & Women's Health》1993,38(Z1):72s-79s
External cephalic version has been used periodically for centuries to manage breech presentations. As cesarean section rates have escalated in the last two decades, ways to curb this rise have been evaluated. By reducing the number of infants that arrive in labor in a representation, it is possible to impact the overall cesarean section rate. External cephalic version is a safe, effective method when used in appropriate cases of breech presentation. A forward or backward roll can be accomplished in women at term with singleton gestations, adequate amniotic fluid, and reactive nonstress tests. Parity, fetal and placental position, and descent of the presenting part may all influence the success rate of the version. 相似文献
42.
43.
Piotr Kozlowski Alastair M. Buchan Ursula I. Tuor Dong Xue Zhi-Gao Huang Karen E. Chaundy John K. Saunders 《Magnetic resonance in medicine》1997,37(3):346-354
31P, 1H and lactate spectroscopic imaging was used to evaluate the effects of hypothermia on focal cerebral ischemia produced by middle cerebral artery occlusion. The effects on high energy phosphate metabolism, pH, lactate and NAA were investigated in 24 spontaneously hypertensive rats subjected to either permanent or transient ischemia. Under either normothermic (37.5°C) or hypothermic (32°C) conditions, with permanent 6-h occlusion, there was little difference between groups in either the NMR measurements or the volume of infarction. In animals that underwent 3 h of ischemia followed by 12 h of reperfusion, the ischemic changes in lactate, pH, NAA, and high-energy phosphate returned toward control values, and there was a protective effect of hypothermia (infarct volume of 211 ± 26 and 40 ± 14 mm3 in normothermic and hypothermic groups, respectively). Thus, hypothermia did not ameliorate the changes in lactate, pH, NAA, or high energy phosphate levels occurring during ischemia, however, during reperfusion there was an improvement in both the recovery of these metabolites and pathological outcome in hypothermic compared with normothermic animals. 相似文献
44.
A. Dornhorst M. Davies V. Anyaoku S. M. Hampton R. S. Elkeles R. W. Beard D. G. Johnston 《Clinical endocrinology》1991,34(3):211-213
Fasting plasma proinsulin, insulin and glucose concentrations were measured in ten women with mild gestational diabetes and ten controls matched for race, age (32 +/- 6 vs 31 +/- 6 years), body mass index (28 +/- 8 vs 27 +/- 6) and gestational week (24 +/- 4 vs 25 +/- 4 weeks). There was no significant difference in fasting plasma glucose between these gestational diabetics and their controls (median 4.7, range 3.7-6.0 mmol/l vs 4.5, range 3.4-5.3 mmol/l). The fasting proinsulin levels were significantly higher in the gestational diabetics compared with the controls (median 12.2, range less than 4-14.8 pmol/l vs 5.8, range less than 4-12.8 pmol/l, P less than or equal to 0.02, Wilcoxon Summed Rank Test), while the calculated intact insulin levels (immunoreactive insulin minus proinsulin) were significantly lower (median 14.5, range 6.3-81.8 pmol/l vs 51.6, range 11.7-312 pmol/l, P less than or equal to 0.01). The ratio of proinsulin to calculated intact insulin was significantly higher in the gestational diabetics than the controls (median 0.66, range 0.16-2.04 vs 0.12, range 0.03-0.62), P less than or equal to 0.01). These results demonstrate that gestational diabetics, with normal fasting plasma glucose values, have abnormalities in pancreatic beta-cell secretion, which are likely to be important both in the aetiology of gestational diabetes and non-insulin dependent diabetes. 相似文献
45.
Because attitudes concerning a topic can diminish the effectiveness of educational materials, previously identified attitudes concerning calcium intake were explored through focus group interviews during the developmental stages of calcium education materials. Although four focus groups of six to seven participants were planned, each of the four groups consisted of two to six women. All focus groups followed the same format, lasting for 60–90 min; questions progressed from the general to more specific. The focus groups revealed several attitudinal barriers toward dietary behavioural change, including lack of prior interest in the topic and lack of time. Attitudes about dairy calcium included the belief that dairy foods were high in fat and should be avoided, and the belief that dairy foods would cause stomach upsets. Also, neither younger nor older women felt that osteoporosis was a problem their age group needed to address. Readability scales were not necessarily predictive of preference. This study shows that focus group interviews make a valuable contribution to planning and evaluating nutrition education materials. 相似文献
46.
Mahrdad Farahmand M.D. Brett C. Sheppard M.D. Clifford W. Deveney M.D. Karen E. Deveney M.D. Richard A. Crass M.D. 《Journal of gastrointestinal surgery》1997,1(2):182-187
Between 1989 and 1995 we performed completion gastrectomy for non-malignant disease in 21 patients (11 men and 10 women, mean
age 48.4 years). These patients had undergone a total of 48 prior gastric operations. Indications for completion gastrectomy
in this group were anastomotic ulceration with stricture in eight patients, alkaline reflux gastritis and/or esophagitis in
eight, postsurgical gastroparesis in two, gastroesophageal necrosis in two, and gastrocutaneous fistula in one. Major preoperative
symptoms included nausea and vomiting in 16 cases, abdominal pain in 15, dysphagia in 14, heartburn in seven, and weight loss
in five. Following completion gastrectomy, five patients (24%) had serious complications and there was one postoperative death
(5%). Five patients were lost to follow-up. For the remaining 15 patients, mean follow-up has been 30 months with a range
of 1 to 70 months. These patients were all interviewed and eight (53%) report significant improvement, two (13%) report moderate
improvement, and four (27%) report no improvement; one patient (7%) has had worsening of symptoms since undergoing completion
gastrectomy. The average body weight index was essentially unchanged after completion gastrectomy. We conclude that completion
gastrectomy with Roux-en-Y esophagojejunostomy results in a favorable outcome in the majority of selected patients with diseases
of the foregut who are unresponsive to less radical treatment.
Presented at the Thirty-Seventh Annual Meeting of The Society for Surgery of the Alimentary Tract, San Francisco, Calif.,
May 19–22, 1996. 相似文献
47.
48.
John T. Pardeck John W. Murphy Karen A. Callaghan 《Early child development and care》1994,97(1):67-72
This article suggests that the United States educational system needs significant changes. The goal of the article is to present a basic educational philosophy that would facilitate this reform. Specifically, education should be viewed as not only a means to an end that teaches basic skills for employment, but also as a process that enhances social development and self-actualization. Recommendations are offered to achieve this important goal. 相似文献
49.
Karen Rosendahl Stein Magnus Aukland Kari Fosse 《European Radiology Supplements》2004,14(4):L138-L145
Appendicitis is the commonest acute surgical emergency of childhood, and occurs in approximately 2–4 per 1000 infants. It is usually seen in infants older than 5 years but can occur at any age. Atypical clinical findings are seen in 30–50% of children, especially the younger ones, and often leads to a delayed diagnosis. Preoperative clinical assessment alone has yielded an accuracy ranging between 70 and 90% but is associated with a normal appendectomy rate of 13–25%. Preoperative imaging using the graded compression US technique and/or different helical CT techniques has been able to reduce this rate to 3–7% without an increase in perforation rate. An extensive review of the literature revealed several papers examining the accuracy of different imaging modalities and strategies of acute appendicitis in children. The reported sensitivity of US varied between 87 and 95%, vs 95–97% for helical CT, while the specificity ranged between 85 and 98% for US and 94 and 97% for helical CT. Only one truly randomised study was found, showing that compared with US alone, a combination of US and helical CT increased the sensitivity from 86 to 99%, while the specificity decreased from 95 to 89%. We conclude that imaging should be performed in all children with suspected appendicitis and that US should be the initial procedure with CT as a complementary tool. 相似文献
50.
Margaret J. Harrison Kaysi Eastlick Kushner Karen Benzies Gwen Rempel Cathy Kimak 《分娩》2003,30(2):109-115
ABSTRACT: Background: Increasingly, women seek involvement in decisions about their health care. The purpose of this study was to examine women's experience of, and satisfaction with, their involvement in health care decisions during a high‐risk pregnancy. Methods: Forty‐seven women with hypertension or threatened preterm delivery (including multiple births) were interviewed after the birth of their child. They received prenatal care at home from nurses in a community program or were hospitalized. The in‐depth interviews were audiotaped and transcribed; data were analyzed using constant comparative methods. Results: Women identified an increased feeling of responsibility for the health of their baby and themselves, but differed in choosing active or passive involvement in health care decisions. Women who wanted active involvement achieved it through one of three processes: struggling for, negotiating, or being encouraged. Women who wanted passive involvement and women facing health crises used the process of trusting in the expertise of nurses and physicians. Women were satisfied if the care from health care professionals was congruent with how they wanted to be involved in decision‐making. Conclusions: Although most women want to be actively involved in health decision‐making during a high‐risk pregnancy, some prefer a passive role. The setting of prenatal care, community‐based or in‐hospital, was less important than the ability of nurses and physicians to support the woman in her preferred role in decision‐making. (BIRTH 30:2 June 2003) 相似文献