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61.
Society often expects mothers and fathers to share equally in the perinatal grief process because the child was a common bond between them. Unfortunately, in perinatal grief, this is not always the case. The mother and the father can experience incongruent grieving and use discordant coping mechanisms. It is important to evaluate these differences to facilitate communication between the distraught parents. Improved communication can in turn facilitate the grieving process.  相似文献   
62.
The Defense Women's Health Research Initiative commissioned a review of the literature of women's health issues. This was performed and published by the Institute of Medicine. In this publication it was noted that health promotion and disease prevention in women should be an area of high priority for military medicine. This article details some of the ways in which exercise may make substantial contributions to this goal.

The available evidence indicates that there is an inverse association between physical activity and a variety of chronic diseases. Moreover, physical activity appears to influence psychological well-being. Aerobic exercise is the mode most frequently studied, and appears to confer positive changes, but other forms of exercise may prove to be equally beneficial. However, the appropriate duration, intensity, and frequency of the exercise have not been determined for any of these chronic health problems and must be considered before global recommendations can be offered. Efforts to promote physical activity within the community, schools, and homes must be initiated to achieve the goals set forth in Healthy People 2000, so the health of our women can improve. Future studies will be required to identify mechanisms whereby physical activity confers benefit.  相似文献   

63.
Recent reports suggest that oxygen radical-induced lipid peroxidation plays a role in the retrograde degeneration of motor neurons following facial nerve axotomy in the neonatal rat. The purpose of the present study was to explore this notion further by testing the neuroprotective properties of two novel brain-penetrating, lipid peroxidation inhibitors, U-101033E and U-104067F, in this model of neuronal degeneration. In Experiment 1, 14-day-old rats were pretreated with 3, 10, or 30 mg/kg U-101033E (po) 10 min before right facial nerve axotomy (Day 0) and then posttreated once a day from Day 1 to Day 6, and once every other day from Day 8 to Day 21. Rats were sacrificed 21 days postaxotomy and surviving cholinergic cell bodies were identified using choline acetyltransferase immunocytochemistry. Both 10 and 30 mg/kg U-101033E significantly enhanced motor neuron survival, with survival rates of 65.9–88.9% being noted in comparison to 51.7–62% survival in vehicle controls (P ≤ 0.05). Experiment 2 demonstrated a significant neuroprotective effect of 10 and 30 mg/kg U-104067F using the same dosing schedule. Experiment 3 was designed to test whether shorter periods of drug exposure (e.g., 5 or 7 days) would be sufficient to preserve motor neurons in rats treated with 10 mg/kg U-101033E. The results suggested that as little as 5 days of drug treatment is sufficient to enhance motor neuron survival. Finally, Experiment 4 demonstrated an 18–19% increase in motor neuron survival in rats treated with 10 and 30 mg/kg U-104067F for 5 consecutive days postaxotomy. Taken together, the attenuation of motor neuron degeneration by the two pyrrolopyrimidine lipid peroxidation inhibitors, U-101033E and U-104067F, lends support to the notion that lipid peroxidation contributes to the pathogenesis of axotomy-induced neurodegeneration.  相似文献   
64.
Porphyrin dimers 9 with either linkages and possible isomers bis[1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2- vinylporphin-4-yl]ethyl] ether (10) bis[1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-4- vinylporphin-2-yl]ethyl] ether (11), and 1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2-vinylporph in- 4-yl]ethyl 1-[6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-4-vinylporph in- 2-yl]ethyl ether (12) were synthesized from the corresponding (1-hydroxyethyl)vinyldeuteroporphyrin IX dimethyl esters (Hvd). The pure Hvd isomers 2-(1-hydroxyethyl)-4-vinyldeuteroporphyrin IX dimethyl ester (7) and 4-(1-hydroxyethyl)-2-vinyldeuteroporphyrin IX dimethyl ester (8) were obtained from 2-acetyl-4-(1-hydroxyethyl) deuteroporphyrin IX dimethyl ester (3) and 4-acetyl-2-(1-hydroxyethyl)deuteroporphyrin IX dimethyl ester (4). Porphyrins 3 and 4 were prepared either by partial reduction of 2,4-diacetyldeuteroporphyrin IX dimethyl ester (2) or by oxidation of hematoporphyrin IX dimethyl ester (1) by using tetra-n-propylammonium perruthenate (Prn4N)(RuO4) with N-methylmorpholine N-oxide as an oxidizing agent. The in vivo photosensitizing ability and therapeutic ratios of dimers 9-12 were compared with that of Photofrin II in the SMT-F tumor growing subcutaneously in DBA/2 Ha mice. These dimers were found to have better tumoricidal activity than Photofrin II with reduced skin phototoxicity.  相似文献   
65.
OBJECTIVES: The incidence of bacterial microleakage, pulp inflammation and necrosis associated with dentine etching treatments prior to restoration are not known. Consequently, to resolve some of the controversy surrounding the effects and importance of vital dentine etching, the authors investigated these factors. METHODS: 110 standardised class V cavities were cut into buccal dentine, without exposing the pulp of teeth scheduled for extraction for orthodontic reasons. Cavities were either left unetched, or etched with the non-equivalent treatments of phosphoric acid gel for 60s or Ethylenediaminetetraacetic acid (EDTA) for 30s, prior to placement of composite resin. Teeth were collected and pulp responses were evaluated according to ISO guidelines, using pathohistomorphometric analysis and ANOVA statistics. RESULTS: Etching was found to be correlated to bacterial microleakage (p=0.0001) and tertiary dentine formation (p=0.0023). Bacterial microleakage was correlated to inflammatory activity (p=0.0001). The frequency of bacterial microleakage was: no etching (65%), EDTA (51%) and phosphoric acid (PA) (20%). SIGNIFICANCE: Vital dentine etching treatment is of extreme importance for the placement of RC to minimise bacterial microleakage. PA etching proved to be more effective at preventing bacterial microleakage than non-etching, and etching with EDTA.  相似文献   
66.
67.
Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
68.
69.
The resolution of three 2-substituted derivatives of idazoxan is described. The enantiomers show large separations in activity in a variety of in vitro and in vivo tests, and the active isomers are all potent and selective antagonists at the alpha 2-adrenoreceptor. The significance of these results in relation to those published on the enantiomers of idazoxan and to those on optically active alpha 2-adrenoreceptor agonists is discussed.  相似文献   
70.
A major problem in tracheal transplantation is the restoration of an adequate vascular supply to the transplanted trachea. In 12 piglets, a segment (6 rings) of thoracic trachea was removed and the excised segment was then sutured back in place. In 9 animals (group A), a vascularized omental flap was wrapped around the autotransplanted trachea. In the other 3 pigs (group B), the omentum was not used. Eight of 9 group A pigs were killed, 1 or 2 months later, having had no signs of airway obstruction; the 9th pig was killed after 14 days because of airway obstruction. The 3 pigs in group B were killed after 11 to 13 days because of progressive respiratory obstruction. In the 8 asymptomatic pigs in group A, the omental flap was viable and tracheal growth was normal with no differences in diameter between normal and autotransplanted trachea. Histologically intact cartilage was lined with respiratory epithelium. In the one group A pig who was killed early, the omental flap was necrotic. In this pig and in the 3 group B animals, extensive tracheal necrosis and nonviable cartilage were observed. These findings indicate that in the pig, a 6-ring segment of trachea can be transplanted with vascularization provided by an omental flap.  相似文献   
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