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101.
102.
The list of LDL receptor superfamily relatives is still growing. The two most recently discovered family branches are (1) a set of receptors characterized by expression in brain and a very close relationship to the LDL and VLDL receptors, and (2) highly cross-species (man, mouse, rabbit, chicken) conserved complex mosaic receptors which contain structural domains so far not found in the superfamily. At present, we know very little about the physiological function(s) of these molecules. They can be safely assumed, based on the presence of seven, eight or 11 clustered LDL receptor ligand binding repeats, to recognize mammalian apolipoprotein E but, based on the absence of apolipoprotein E in birds, they may exhibit interactions quite different from and/or in addition to typical lipoprotein receptors in vivo.  相似文献   
103.
AIMS/BACKGROUND: The introduction of the adjunctive use of antiproliferatives to trabeculectomy has greatly improved the success rate of this operation. Trabeculectomy with antiproliferative treatment, however, is usually associated with a cystic and thin walled filtering bleb, which may be more susceptible to infection. The objective of this study was to evaluate the incidence, clinical findings, and risk factors of delayed onset, bleb related infection after trabeculectomy with adjunctive mitomycin C (MMC) or 5-fluorouracil (5-FU) treatment. METHODS: The records of 632 glaucoma patients who underwent 966 trabeculectomies, with and without the use of adjunctive MMC or 5-FU treatment, between January 1985 and February 1995 were analysed. The mean follow up period was 3.5 (2.4) years (range 0.1 to 11.2 years). The mean patient age was 54.8 (18.8) years (range 0 to 88 years). RESULTS: Bleb related infection occurred in one of 76 trabeculectomies that did not receive antiproliferatives (1.3%), three of 228 treated with 5-FU (1.3%) trabeculectomies, and seven of 662 treated with MMC (1.1%). Five eyes developed blebitis; six eyes developed endophthalmitis. Bleb related infection developed an average of 3.1 (1.6) (range 0.4 to 6.0) years after trabeculectomy. All eyes had avascular or hypovascular blebs that were cystic in shape before infection and all eyes had reduced intraocular pressure. Early wound leaks and chronic, intermittent bleb leaks were identified to be risk factors for the bleb related infection. CONCLUSION: The incidence of delayed onset, bleb related infection after trabeculectomy with antiproliferative treatment is similar to that after trabeculectomy without antiproliferatives.  相似文献   
104.
The objective of this investigation is to stabilize a sensorless vector control system of induction motors by means of an adaptive observer in regenerating mode at very low speed. The adaptive observer gain is designed by means of the Routh–Hurwitz criterion. It is verified by simulation and experiment that the proposed system is stable. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(4): 78–87, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10202  相似文献   
105.
One hundred and twelve forearms in 56 preserved cadavers were dissected to assess the incidence of Martin-Gruber connections in a population in South Africa. The connections were found in 13 cadavers (23%) and one was bilateral. There were no significant racial or sexual differences in the incidence. The course of Martin-Gruber connections and their anatomical relationship with the ulnar artery are illustrated.  相似文献   
106.
The mechanics of the condensing behavior of vapor bubbles in a subcooled bulk flow is complicated and influenced by both heat and mass transfer. To examine the characteristics of such thermal-nonequilibrium two-phase flow, experimental and analytical researches have been made. In the experiment, the movement of each vapor bubble in a flowing channel was recorded on video tapes and analyzed by an image processing system. As result, the distributions of void fraction along the test section were obtained. In the analysis, a simple analytical model was introduced to predict the distributions of void fraction and liquid subcooling temperature. By considering the rate of vapor condensation along the flow direction, the differential equation of energy balance between two phases was obtained. Integration of this equation yielded the void fraction and bulk liquid subcooling at any position. The condensation rate was estimated as a function of the local liquid subcooling, interfacial area and mass velocity. Finally, a close fit between calculated results and experimental data was obtained.  相似文献   
107.
The influence of timing of administration of preoperative pentazocine on pain and analgesic requirements after surgery was studied in 46 patients undergoing total abdominal hysterectomy. Twenty-three patients received thiamylal 5 mg.kg-1 on induction of anesthesia, followed by pentazocine 30 mg or 60 mg before surgical incision (group A). Twenty-three control patients received pentazocine 30 mg or 60 mg, 5 min after abdominal incision (group B). The visual analogue scales for pain 24 h after operation were 6.0 cm at 30 mg dose in group A or 5.3 cm at 60 mg dose in group A and 5.7 cm at 30 mg dose in group B or 4.7 cm at 60 mg dose in group B. There were no differences in the visual analogues scales. Pentazocine consumption in the first 24 h after surgery was 67.5 mg at 30 mg dose in group A or 52.5 mg at 60 mg dose in group A and 70.9 mg at 30 mg dose in group B or 51.8 mg at 60 mg dose in group B. We conclude that postoperative pentazocine consumption and pain scores are no different when pentazocine is given before or after skin incision for abdominal hysterectomy and that there is no clinically useful pre-emptive analgesic effect with these doses of pentazocine.  相似文献   
108.
Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) produced by various bacteria has been intensively investigated as a promising biodegradable plastic, but required a supply of an expensive precursor as a secondary carbon source for its production. In a previous study, we identified a new bacterial strain, Rhodococcus aetherivorans IAR1, which synthesizes PHBV from toluene without the supply of a precursor. Toluene is the volatile organic compound most abundantly emitted to the environment. In the present paper, we show that R. aetherivorans IAR1 produces triacylglycerols (TAGs) simultaneously with PHBV. Both PHBV and TAGs were synthesized before the nitrogen source is completely exhausted. The cellular content of PHBV reached 10% of cell dry weight (CDW) and its synthesis ceased even during intermittent supply of toluene. However, accumulation of TAGs continued during cultivation and their cellular content reached 24% of CDW at the end of cultivation. Cerulenin inhibited TAG production and increased PHBV cellular content up to 30% of CDW. The mole fraction of 3-hydroxyvalerate (3HV) in PHBV produced from toluene increased from 60% to 80% during its accumulation. Fatty acid compositions of TAGs produced from acetate and toluene were different. At the end of cultivation, the mole fraction of C17:0, one of odd-carbon number fatty acids, was 5% on toluene or 10% on acetate while the mole fraction of 3HV in PHBV from toluene was as high as that in PHBV from acetate, suggesting that a C5 intermediate of toluene degradation might directly become a precursor of 3HV whereas propionyl-CoA is required for the incorporation of C17:0 into TAGs.  相似文献   
109.
110.
Myocardial contrast echocardiography was used to characterize changes in the regional and transmural myocardial blood flow distribution that were provoked by rapid atrial pacing stress in patients with coronary artery diseases. In patients with coronary organic stenosis, a decrease in the myocardial contrast-enhancement in the subendocardial half after rapid atrial pacing was associated with stress-induced chest pain and electrocardiographic ST-T changes. The decrease in the myocardial contrast-enhancement in the subendocardial half after rapid atrial pacing was not observed in patients without coronary stenosis or after coronary angioplasty. Thus, the finding was considered to reflect myocardial ischemia. Pacing-induced decreases in myocardial contrast-enhancement were observed in some patients with old myocardial infarction and significant resting coronary collaterals. In these patients, myocardial ischemia was considered to have developed at rapid pacing because collateral function was good enough to perfuse the infarct myocardium at rest, but was not good enough to prevent myocardial ischemia at stress. Thus, myocardial contrast echocardiography seems to be particularly useful in assessing myocardial ischemia at stress due to coronary stenosis in patients with angina pectoris and due to poor dynamic collateral function in patients with old myocardial infarction.  相似文献   
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