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71.
72.
Thrombophilia and pregnancy complications 总被引:15,自引:0,他引:15
Kujovich JL 《American journal of obstetrics and gynecology》2004,191(2):412-424
OBJECTIVE: This systematic review examines the strength of the association between thrombophilia and recurrent pregnancy loss and other serious obstetric complications.Study design Electronic databases and manual bibliography searches were used to identify studies evaluating the association between thrombophilia and pregnancy loss, preeclampsia, fetal growth retardation, and placental abruption. RESULTS: Thrombophilic disorders are associated with an increased risk of fetal loss in the majority of case control and cohort studies. The risk is increased throughout pregnancy, but may be higher in the second and third trimester. The common pathologic finding of placental infarction suggests unexplained fetal loss may result from uteroplacental insufficiency and thrombosis. Thrombophilic disorders are not consistently associated with preeclampsia, fetal growth retardation, or placental abruption. Preliminary data suggest prophylactic anticoagulation may improve outcome in thrombophilic women with unexplained recurrent fetal loss. CONCLUSION: Women with thrombophilia have an increased risk of pregnancy loss and possibly other serious obstetric complications, although definition of the magnitude of risk will require prospective longitudinal studies. Preliminary data suggesting prophylactic anticoagulation may improve gestational outcome provide a rationale for prospective randomized trials in thrombophilic women with unexplained recurrent fetal loss. 相似文献
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Reschke M Somers JT Leigh RJ Krnavek JM Kornilova L Kozlovskaya I Bloomberg JJ Paloski WH 《Aviation, space, and environmental medicine》2004,75(8):700-704
Square-wave jerks (SWJs) are small, involuntary saccades that disrupt steady fixation. We report the case of an astronaut (approximately 140 d on orbit) who showed frequent SWJs, especially postflight, but who showed no impairment of vision or decrement of postflight performance. These data support the view that SWJs do not impair vision because they are paired movements, consisting of a small saccade away from the fixation position followed, within 200 ms, by a corrective saccade that brings the eye back on target. Since many returning astronauts show a decrement of dynamic visual function during postflight locomotion, it seems possible that frequent SWJs improved this astronaut's visual function by providing postsaccadic enhancement of visual fixation, which aided postflight performance. Certainly, frequent SWJs did not impair performance in this astronaut, who had no other neurological disorder. 相似文献
75.
Altena TS Michaelson JL Ball SD Thomas TR 《Medicine and science in sports and exercise》2004,36(8):1364-1371
PURPOSE: This study compared the effects of continuous (CON-EX) and intermittent (INT-EX) exercise on postprandial lipemia (PPL). METHODS: Subjects were 18 inactive males (N = 7) and females (N = 11), aged 25 +/- 1.8 yr (mean +/- SE), VO2max 38.4 +/- 1.5 (mL x kg(-1)x min(-1)), and BMI 23.2 +/- 0.8 (kg x m(-2)). After 48-h activity and 24-h dietary control periods, subjects consumed a high-fat meal (HFM) containing 1.5 g fat (88% of calories), 0.05 g protein, and 0.4 g carbohydrate per kilogram body weight for three trials: no exercise (NOEX), CON-EX, and INT-EX. Both exercise trials consisted of 30 min of treadmill running at 60% VO2max. INT-EX was conducted in a single session of three bouts, each lasting 10 min and separated by a 20-min rest period. Blood was collected before the HFM (0 h) and at 2, 4, 6, and 8 h post-HFM. Exercise trials were completed 12 h before the HFM. Trials were separated by 7-10 d and were performed in random order. RESULTS: Plasma analysis indicated TG incremental area under the curve (AUCI) and TG incremental peak (PeakI) were significantly lower in INT-EX compared with NOEX, but CON-EX was not different from INT-EX or NOEX. Compared with females, males had significantly higher AUCI and PeakI in both exercise trials, but genders were not different in the NOEX trial. No difference was discovered among trials in high density lipoprotein (HDL)Total-C, HDL2-C, and HDL3-C, or fasting total cholesterol (TC) or fasting TC:HDL ratio. Females had higher fasting HDLTotal-C, HDL2-C, and HDL3-C compared with males. No gender or trial difference was found for fasting TC or TC:HDL ratio. CONCLUSIONS: Our data suggest that a single bout of INT-EX is more effective than CON-EX for lowering PPL as compared with NOEX in inactive, normolipidemic individuals. 相似文献
76.
OBJECTIVE: The objective of this investigation was to provide a new CT-based classification of acetabular fractures. MATERIALS AND METHODS: The axial CT scans of 112 randomly selected acetabular fractures in patients admitted to a level 1 trauma center between January 1998 and December 2000 were analyzed by an experienced orthopedic trauma surgeon and two experienced emergency radiologists. When available, 3D reformatted images were analyzed as well. The fracture pattern for each acetabular fracture, with respect to column walls and extension beyond the acetabulum, when present, was recorded. Fracture comminution was not a defining characteristic. RESULTS: Analysis of the 112 acetabular fracture patterns showed that each fracture fell into one of four broad categories. Category 0 included wall fractures only. Category I included acetabular fractures limited to a single (anterior or posterior) column. Category II fractures included those involving both the anterior and posterior columns; category II fractures were further subdivided into those with no fracture extension beyond the acetabulum, those with superior or inferior extension, and those with both superior and inferior extensions beyond the acetabulum. Category III fractures included only the "floating" acetabulum, which is defined as an acetabular fracture in which the acetabulum is separated from the axial skeleton both anteriorly and posteriorly. CONCLUSION: The axial CT display of acetabular fracture patterns provides a basis for a classification of acetabular fractures that is simple, unambiguous, readily understood by both radiologists and orthopedic surgeons and provides clear direction for both diagnosis and surgical treatment planning. Category and subcategory fracture specificity creates a mechanism for intra- and interdepartmental postoperative assessment of any of the individual acetabular fracture types. 相似文献
77.
Exercise-induced reduction in obesity and insulin resistance in women: a randomized controlled trial 总被引:8,自引:0,他引:8
Ross R Janssen I Dawson J Kungl AM Kuk JL Wong SL Nguyen-Duy TB Lee S Kilpatrick K Hudson R 《Obesity research》2004,12(5):789-798
OBJECTIVES: To determine the effects of equivalent diet- or exercise-induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat, and insulin sensitivity in obese women. RESEARCH METHODS AND PROCEDURES: Fifty-four premenopausal women with abdominal obesity [waist circumference 110.1 +/- 5.8 cm (mean +/- SD)] (BMI 31.3 +/- 2.0 kg/m2) were randomly assigned to one of four groups: diet weight loss (n = 15), exercise weight loss (n = 17), exercise without weight loss (n = 12), and a weight-stable control group (n = 10). All groups underwent a 14-week intervention. RESULTS: Body weight decreased by approximately 6.5% within both weight loss groups and was unchanged in the exercise without weight loss and control groups. In comparison with controls, cardiorespiratory fitness improved within the exercise groups only (p < 0.01). Reduction in total, abdominal, and abdominal subcutaneous fat within the exercise weight loss group was greater (p < 0.001) than within all other groups. The reduction in total and abdominal fat within the diet weight loss and exercise without weight loss groups was greater than within controls (p < 0.001) but not different from each other (p > 0.05). Visceral fat decreased within all treatment groups (p < 0.008), and these changes were not different from each other. In comparison with the control group, insulin sensitivity improved within the exercise weight loss group alone (p < 0.001). DISCUSSION: Daily exercise without caloric restriction was associated with substantial reductions in total fat, abdominal fat, visceral fat, and insulin resistance in women. Exercise without weight loss was also associated with a substantial reduction in total and abdominal obesity. 相似文献
78.
OBJECTIVE: To examine the impact of managed care on the number and types of services offered by substance abuse treatment (SAT) facilities. Both the number and types of services offered are important factors to analyze, as research shows that a broad range of services increases treatment effectiveness. DATA SOURCES: The 2000 National Survey of Substance Abuse Treatment Services (NSSATS), which is designed to collect data on service offerings and other characteristics of SAT facilities in the United States. These data are merged with data from the 2002 Area Resource File (ARF), a county-specific database containing information on population and managed care activity. We use data on 10,513 facilities, virtually a census of all SAT facilities. STUDY DESIGN: We estimate the impact of managed care (MC) on the number and types of services offered by SAT facilities using instrumental variables (IV) techniques that account for possible endogeneity between facilities' involvement in MC and service offerings. Due to limitations of the NSSATS data, MC and specific services are modeled as binary variables. PRINCIPAL FINDINGS: We find that managed care causes SAT facilities to offer, on average, approximately two fewer services. This effect is concentrated primarily in medical testing services (i.e., tests for TB, HIV/AIDs, and STDs). We also find that MC increases the likelihood of offering substance abuse assessment and relapse prevention groups, but decreases the likelihood of offering outcome follow-up. CONCLUSION: Our findings raise policy concerns that managed care may reduce treatment effectiveness by limiting the range of services offered to meet patient needs. Further, reduced onsite medical testing may contribute to the spread of infectious diseases that pose important public health concerns. 相似文献
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