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991.
Fear of falling may constitute an independent risk factor for disability, leading older people to unnecessarily restrict their activity. Sixty older adults with chronic dizziness and 66 healthy controls were studied to help clarify the interrelationships among demographic factors, psychological status, physical health, and fear of falling. Chronic dizziness was strongly associated with fear of falling; among dizzy patients, nearly half (47%) expressed fear of falling, in comparison with 3% of controls. In participants with dizziness, 3 factors predicted fear of falling: an activity of daily living score, the revised Symptom Checklist 90 Depression (L. R. Derogatis, 1983) score, and stability when standing with feet together. These results support the concept that fear of falling is multiply determined and that psychological factors play a major role in influencing the symptoms and responses in many older patients with dizziness. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
992.
This prospective, double-blind, randomized trial assessed the effectiveness of high-dose tranexamic acid given in the preoperative period on blood loss in patients undergoing cardiopulmonary bypass. One hundred fifty patients scheduled to undergo cardiac operations with cardiopulmonary bypass were randomized into three groups of equal size. The first group received 10 gm of tranexamic acid intravenously over 20 minutes before sternotomy and a placebo infusion over 5 hours. The second group received 10 gm of tranexamic acid over 20 minutes and then another 10 gm infused intravenously over 5 hours. The control group received a placebo bolus and a placebo infusion over 5 hours (0.9% normal saline solution). The blood loss after the operation was measured at 6 hours and 24 hours. The homologous blood and blood products given during and up to 48 hours after operation were recorded. Eighteen percent of the control group patients shed more than 750 ml blood in 6 hours compared with only 2% in both tranexamic acid groups. Patients who shed more than 750 ml blood required 93% more red blood cell transfusions than patients without excessive bleeding. Tranexamic acid (10 gm) given intravenously in the period before cardiopulmonary bypass reduced blood loss over 6 hours by 50% and over 24 hours by 35%. Continued tranexamic acid infusion (10 gm over 5 hours) did not reduce bleeding further. There was no difference in the coagulation profile before operation between patients with and without excessive bleeding. However, coagulation tests done in the postoperative period indicated ongoing fibrinolysis and platelet dysfunction in patients with excessive bleeding.  相似文献   
993.
994.
995.
We have demonstrated the presence of epidermal growth factor (EGF) and its receptors in human non-gestational corpora lutea. To determine further the characteristics of EGF receptor binding, we examined 30 human corpora lutea throughout the luteal phase and during pregnancy. Scatchard plots of EGF binding in 29 of the 30 corpora lutea were curvilinear, suggesting negative co-operativity. The mean +/- SE of the association constant Ka was (0.9 +/- 0.2) x 10(9) l/mol, the dissociation constant Kd was (2.2 +/- 0.3) x 10(-9) mol/l and the number of binding sites (Rt) was (15.8 +/- 2.1) x 10(-19) mol/micrograms protein for non-gestational corpora lutea. The Kd increased significantly in late pregnancies compared to early pregnancies (P = < 0.005), while Rt was significantly higher in term pregnancies than in either early pregnancy (P < 0.01) or the menstrual cycle (P < 0.001). Corpora lutea atretica (n = 2) and ovarian stroma (n = 6) did not show any EGF binding activity. Our findings demonstrate the presence of specific EGF receptors in human corpora lutea of both the menstrual cycle and pregnancy. The changes in EGF binding parameters in early pregnancy suggest that there may be a relationship between the role of EGF and ovarian steroidogenesis.  相似文献   
996.
The impact of perfusion technique and mode of pH management during cardiopulmonary bypass has not been well characterized with respect to postoperative cardiovascular outcome. METHODS: This double-blind, randomized study comparing outcomes after alpha-stat or pH-stat management and pulsatile or nonpulsatile perfusion during moderate hypothermic cardiopulmonary bypass was undertaken in 316 patients undergoing coronary artery bypass operations. RESULTS: Cardiovascular morbidity and mortality were not affected by pH management, and the incidence of stroke (2.5%) did not differ between groups. Overall in-hospital mortality was 2.8%, eight of the nine deaths occurring in the nonpulsatile group (5.1% versus 0.6%; p = 0.018). The incidence of myocardial infarction was 5.7% in the nonpulsatile group and 0.6% in the pulsatile group (p = 0.010), and use of intraaortic balloon pulsation was significantly more common in the nonpulsatile group (7.0% versus 1.9%; p = 0.029). The overall percentage of patients having major complications was also significantly higher in the nonpulsatile group (15.2% versus 5.7%; p = 0.006). Duration of cardiopulmonary bypass, age, and use of nonpulsatile perfusion all correlated significantly with adverse outcome. CONCLUSIONS: Use of pulsatile perfusion during cardiopulmonary bypass was associated with decreased incidences of myocardial infarction, death, and major complications.  相似文献   
997.
Several new genes and markers have recently been identified on the proximal short arm of the human X chromosome in the area of Xp11.23. We had previously generated a YAC contig in this region extending from UBE1 to the OATL1 locus. In this report two polymorphic dinucleotide repeats, DXS6949 and DXS6950, were isolated and characterized from the OATL1 locus. A panel of YAC deletion derivatives from the distal portion of the contig was used in conjunction with the rest of the YAC map to position the new microsatellites and order other markers localizing to this interval. The marker order was determined to be DXS1367-ZNF81-DXS6849-ZNF21-DXS6616-DXS 6950-DXS6949. In the proximal region below OATL1, we have isolated a pair of YACs from the GATA locus, B1026 and C01160. Mapping within these YACs indicates the orientation of DXS1126 and DXS1240, while a cosmid near the OATL1 region reveals the overlap between the YAC contigs from the two loci. This cosmid contains the gene responsible for Wiskott-Aldrich syndrome (WAS) and localizes the disease gene between OATL1 and GATA. These data enable the expansion of the present physical map of the X chromosome from UBE1 to the GATA locus, covering a large portion of the Xp11.23 region. Genetic cross-overs in Xp11.23 support the marker orientation and the position of WAS, contrary to previous reports. With the integration of both physical and genetic maps we have predicted the following marker order: Xpter-UBE1-SYN1/ARAF1/ TIMP1-DXS1367-ZNF81-DXS.6849-ZNF21-DXSy6616++ +-(OATL1, DXS6950-DXS6949)- WAS-(GATA, DXS1126)-DXS1240-Xcen.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
999.
A study to identify the acidic components ofCladophora glomeata active againstAedes triseriatus larvae was extended to a mixture obtained by extracting the dried powdered alga in aqueous suspension at pH 8.5. The presence of 1,9-nonanedioic, 1,10-decanedioic, 1,11-undecanedioic and 4-ketononanoic acids was determined by GC-EIMS and GC-CIMS and confirmed by analytical coinjection GC. The presence of 5-pentyldihydro-2(3H)-furanone, a minor component, was also indicated. The group of major acidic constituents is different from those obtained by extracting driedCladophora with methanol. In contrast to the C10–C14 monocarboxylic acids, which hadLD 50 values<20 ppm againstA. triseriatus, none of the dicarboxylic acids of the series G4–C14, C16, and C22 were active; nor were 4-ketononanoic acid and 5-pentyldihydro-2(3H)-furanone active.  相似文献   
1000.
A straightforward model reduction procedure is developed for high-order multistage systems. It is proposed to generate a partial differential equation from the original system and then to use the orthogonal collocation procedure to establish a low-order reduced model. This low-order model can then be used for time-optimal control with the assurance that the optimal control, as determined for the reduced system, can be applied to the original system. The procedure is illustrated with a 20-plate gas absorber which is eventually reduced to 5 state equations.  相似文献   
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