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1.
In this study, to test an inference from the 1991 Previc hypothesis that right-handers have a right-ear advantage, the durations of hearing for the right and left ears were compared for 81 right- and 45 left-handed high school students. In the present study, right-handedness was associated with a right-ear advantage and left-handedness was associated with a left-ear advantage. In addition, there was a significant positive correlation between the durations of hearing for the right and left ears and the scores for right-handedness for right-handed subjects. The durations of hearing for the right and left ears were negatively correlated with the left-handedness for left-handed subjects. These results suggest hand preference may be related to asymmetry of aural sensitivity.  相似文献   

2.
In this survey of 602 patients treated for carcinoma of the uterine cervix during the period 1944--1968 (with a 100 per cent follow-up) survival rates at 5, 10, 15 and 20 years after radiotherapy were 41, 28, 18 and 11 per cent. The crude five-year cure rate of over 70 per cent for Stage I and 58 per cent for Stage II cases and an overall five-year survival rate of 42 per cent for all stages compares favourably with results published from other institutions in the United Kingdom.  相似文献   

3.
C Darling  DM Shah  BB Chang  PS Paty  RP Leather 《Canadian Metallurgical Quarterly》1996,224(4):501-6; discussion 506-8
OBJECTIVE: The objective of this article is to determine whether retroperitoneal approach for aortic surgery has certain physiologic, technical advantages. SUMMARY BACKGROUND DATA: The retroperitoneal approach for abdominal aortic reconstruction classically had been reserved for select patients with either high-risk comorbid disease or specific anatomic problems that preclude the transabdominal approach. With increasing appreciation of the physiologic, anatomic, and technical advantages of the extended posterolateral retroperitoneal approach, the authors have expanded its use for repair of all types of aortic visceral and renal artery disease as well as ruptured abdominal aortic aneurysm and infected aortic grafts. METHODS: From January 1981 to September 1995, 2340 retroperitoneal aortoiliac reconstructions were performed in 2243 patients. Aortic reconstructions accounted for 1756 cases: 1109 for elective abdominal aortic aneurysms, 210 for ruptured and symptomatic aortic aneurysms, 399 for occlusive disease, 18 for infected aortic grafts, and 20 for other indications. Iliofemoral disease was the indication for 584 procedures. As experience was gained, this approach also was used for 417 renal and 50 celiac and superior mesenteric artery reconstructions. RESULTS: The mean age was 67 years with 1590 men and 653 women. Overall mortality was 5.2% for all aortic cases: 2.4% for elective, 12.6% for symptomatic, and 29.0% for ruptured aortic aneurysms. Major complications occurred in 12.5% of the elective procedures and in 38.3% of emergency procedures. Over the past 5 years, the average length of hospital for uncomplicated elective abdominal aortic aneurysms was 6.1 days, intensive care unit stay was 0.7 day, and diet was resumed by postoperative day 1. Five-year graft patency was 99% for aneurysms and 95% for occlusive disease. CONCLUSIONS: The retroperitoneal approach offers certain physiologic advantages associated with minimal disturbance of gastrointestinal and respiratory function, thereby reducing the length of intensive care unit and hospital stay. In addition, its technical advantages and flexibility facilitates visceral and juxtarenal aortic reconstructions without the need for thoracotomy.  相似文献   

4.
Previous studies have demonstrated that regionalization of resources for cardiac catheterization, percutaneous coronary artery angioplasty (PTCA), and coronary artery bypass graft surgery (CABG) reduces the rate of procedure use. It was hypothesized that the impact of regionalization would be greater for the elderly and for African-Americans than for other populations. Discharge medical records of 30,901 patients admitted to a Veterans Affairs (VA) medical center between October 1, 1993, and September 30, 1994, with a diagnosis of coronary artery disease were analyzed. The presence of a cardiac catheterization laboratory in the patients' local VA facility significantly increased the likelihood of undergoing catheterization, PTCA, and CABG, as determined by odds ratios and associated confidence limits estimated by logistic regression techniques. The presence of a cardiac surgical facility also significantly increased the likelihood of having the procedures. The odds ratios estimating the effects of resource availability were significantly greater for the subgroup of patients aged > or =70 years than for the younger subgroup for catheterization, PTCA, and CABG and for African-Americans than for white patients for PTCA and CABG. Thus, within the VA health care system, regionalization of cardiac procedures has a significant impact on utilization rates of tertiary cardiac procedures. These differences are significantly greater for the elderly and for African-Americans than for the general population.  相似文献   

5.
A method for selecting electron-beam welding (EBW) conditions is developed for specific equipment, thickness, and material of a product. The results can be used for calculating and predicting the welding parameters to reduce the time for preparing products for EBW and the material costs.  相似文献   

6.
A statistical analysis was performed on 40 patients with squamous cell carcinoma of the tongue and mouth floor, which could be followed for 6 months or more after initial treatment in the Department of Otorhinolaryngology, School of Medicine, Keio University during the 14 years from 1983 to 1996. The 5-year survival rate determined by the Kaplan-Meier method for each stage was 100% for Stage I, 77.8% for Stage II, 60.0% for Stage III and 44.4% for Stage IV. Thirteen suffered a relapse after initial treatment and patients with relapses among them have all survived after the subsequent salvage surgery. In contrast, in nine patients with cervical relapse, however, the 5-year survival rate was 11.1% with an unfavorable prognosis. This confirmed that suppressing cervical relapses is important for treating tongue and floor mouth cancers. The treatment strategy in our department is characteristic of positive enforcement of prophylactic neck dissection in the surgery and introduction of neoadjuvant chemotherapy (NAC) in the chemotherapy. Prophylactic neck dissection was performed in the 17 patients and no relapse was observed on the side of prophylactic neck dissection. NAC was performed on 26 patients in consideration of suppressed minute metastases and preserved function and 24 determinable cases were statistically analyzed. Among patients who had received NAC, the oral function was successfully preserved without surgical intervention in six patients both patients who showed complete response (CR) and four out of 14 patients who had a partial response (PR) following NAC. This may indicate that the oral function could be preserved in those patients who exhibited CR following NAC, but that preservation could be difficult in patients who exhibited PR. In addition, concerning the accumulated 5-year survival rate in relation to the effect of NAC, responders (CR + PR) accounted for 90.9% and non-responders (no change + progressive disease following NAC) for 15.0% with a very good outcome noted in the responder group. These figures suggest that responders may have a significantly good prognosis in the multivariant analysis including additional background factors before treatment as well. Accordingly, the present therapeutic measures for non-responders must be reexamined and performed more carefully and accurately as compared with those for responders.  相似文献   

7.
范军 《山西冶金》2008,(4):39-40
通过对电极消耗的原因及计算公式进行分析,发现将电极侧面、前端消耗速度指标作为描述电极消耗的对标指标,可使得不同装备下的电极消耗水平具有更好的可比性,可以使电极消耗工艺差距分析更为直接。  相似文献   

8.
The results of experimental investigations into the zeta potential of ultrafine sulfides (chalcopyrite, tennantite, galenite, sphalerite, pyrite, and pyrrhotine), the floatability of monomineral fractions of sulfides of the floatation coarseness (–0.1 + 0.05 mm) in a mechanical flotation machine, and the floatability fine particles of sulfide (–0.044 + 0.010 mm) in the Hallimond tube are presented. The preparation procedure of ultrafine powders and sulfhydril collectors to measure the zeta potential is presented. Zeta potentials of the surface of mineral particles and insoluble forms of sulfhydril collectors are investigated in the pH range from 2.0 to 12.5 (an acidic medium was formed by using H2SO4 and basic one by using NaOH or Ca(OH)2), and various values of zeta potentials are found for sulfides in the sodium hydroxide and lime medium. Zeta potentials for all sulfides are negative in the NaOH medium at pH > 9.5, they are positive (1–18 mV) in the Ca(OH)2 medium at pH > 11, and zeta potentials for chalcopyrite are positive in the studied range \(p{H_{Ca{{\left( {OH} \right)}_2}}}\) 9.0–12.5. The values of the isoelectric point in the medium of sulfuric acid and sodium hydroxide are as follows: for chalcopyrite—pH 6.5 and 8.8, for tennantite—pH 3.0, for sphalerite—pH 5.1 and 6.4, for pyrite—pH 3.1 and 8.9, and for pyrrhotine—pH 7.0. In the lime medium, the value for tennantite and sphalerite pH 12.0, for galenite—pH 11.2, for pyrite—pH 9.5 and 11.2, and for pyrrhotine—pH 9.5 and 12.1. Measurements of zeta potentials of ultrafine sulfide particles give the opportunity to refine the interaction mechanism of sulfhydril collectors with sulfides and associate the nonselective recovery of final tailings of sulfides in the highly alkaline lime medium with the contribution of the electrostatic component during the adhesion of ultrafine sulfide particles on bubbles and their mechanical carryout into the froth product.  相似文献   

9.
The CPS ID 2 (CPS) chromogenic agar was compared to routine media for use in the isolation, enumeration, identification, and susceptibility testing of bacteria recovered from urine specimens. Of 487 urine specimens, 318 were culture negative, 12 were positive on CPS only, 16 positive on routine only, and 141 positive on both. The enumeration of microorganisms agreed for 96 of the 141 cultures. Fewer organisms were recovered on CPS for 25 cultures, more for 20 cultures. The identification of bacteria from CPS and routine media agreed for all isolates. Susceptibility testing was performed for 100 isolates. The categorical susceptibility test results from isolates grown on CPS agreed with results from routine media for 77 isolates. For the remaining 23 isolates, one or more discrepancies were seen involving 16 different antimicrobial agents; 27 minor, 1 major, and 6 very major errors. After additional testing, there were 10 confirmed errors, 7 minor and 3 very major errors. This study demonstrates that CPS agar is a reliable medium for culturing urine. Susceptibility testing directly from this medium resulted in low error rates for all antimicrobial agents tested.  相似文献   

10.
针对2号高炉近年顺行度低,悬料次数多,阐述2号高炉悬料的种类、特点,分析造成悬料的原因,总结处理经验,对日常操作提出建议。  相似文献   

11.
A method based on discounted income and risk assessment was developed to aid in the selection of dairy sires. The discounted profit generated from milk production of daughters was proposed as the suitable composite selection criterion to combine estimates of predicted transmitting ability (PTA) for yields of milk, fat, and protein and estimates of sire evaluations for dystocia or expected progeny difference. Steps are described to derive discounted profit (defined as expected income) for a sire with known PTA and evaluation for dystocia. The derivation of profit considered costs for semen, dystocia, heifer raising, production and maintenance of the daughter, and income from milk. Variance of income from a sire depended on the reliability of his PTA and evaluation for dystocia. Total variance from a selected set of sires was defined as the risk. A quadratic programming procedure was developed to identify the best set of sires from a given pool of sires that met a desired expected income goal with minimum risk. Combinations of sires with minimum risk for all possible levels of expected income were defined by the expected income variance frontier. The set of sires at the maximum lower boundary for 95% confidence of the expected income variance frontier was defined as the optimum set of sires to be selected; the optimum set maximized the 95% guaranteed expected income. The quadratic programming procedure provided the optimum percentage of cows to be mated to each sire in the selected set.  相似文献   

12.
Modeling of thermomechanical processing of heat-treatable aluminum alloys   总被引:2,自引:0,他引:2  
This paper describes formulation of a model for calculating recrystallized grain size for heat-treatable aluminum alloys subjected to thermomechanical processing for grain size control. When combined with Zerer's equation for the limiting grain size during grain growth in particle-containing materials, the model can be used to calculate the stable grain size after thermomechanical processing. A set of adjunct models and experimental observations have been used to relate alloy composition and processing parameters to the intermediate variables which are inputs to the model for recrystallized grain size. Model results are compared with experimental data from various sources. Modeling results exhibit all of the trends observed in the experimentally-determined grain sizes for AA7075, for AA6063, and for modified AA7475 alloys containing different dispersoid-forming additions.  相似文献   

13.
The effect of tone duration on fundamental frequency (F0) discrimination is greater for complexes containing unresolved harmonics than for those containing resolved harmonics [Plack and Carlyon, J. Acoust. Soc. Am. 98, 1355-1364 (1995)]. Three experiments explored this effect further. The first experiment measured sensitivity (as d') to fundamental frequency (F0) differences for two complexes, both with an F0 of 250 Hz. The first complex was low-pass filtered at 1875 Hz to create a resolved complex and the second was bandpass filtered between 5500 and 7500 Hz to create an unresolved complex. The harmonics for the resolved complex were selected so that no two harmonics were the same between the two observation intervals. Performance for both complexes was measured for tone durations of 20, 40, 80, and 160 ms. For the unresolved complex, the effect of duration was greater than that for the resolved complex and greater than the predictions of a "multiple-looks" model assuming either peripheral (before sampling) or central (after combining samples) sources of variance. The second experiment replicated these results using an F0 of 62.5 Hz with the cutoff frequencies of the bandpass filters divided by four, confirming that the effect is related to resolvability and not to spectral region. In the final experiment, F0 discrimination for pairs of complexes separated by a temporal gap was measured relative to that for one complex. Performance for the resolved and unresolved complexes was similar: Very little effect of gap duration was observed and the results were consistent with the predictions of the peripheral-variance multiple-looks model. Taken together, the results suggest that the pitch mechanism for resolved harmonics uses a relatively short sampling window of around 20 ms, while the mechanism for unresolved harmonics may use a more complex strategy for optimizing the combination of information over time, perhaps involving a flexible integration time.  相似文献   

14.
Aiming to assess the presence of selected anaerobic microorganisms in root canals of human teeth with chronic apical periodontitis. 25 central and lateral upper incisors presenting with radiographic evidence of chronic apical periodontitis were studied. The pulp chamber was opened under aseptic conditions and samples of the root canal content were collected with sterile absorbent paper points, which were placed and dispersed in test tubes containing reduced transport medium RTT. Aliquots were dried on glass slides and stained by indirect immunofluorescence for detection of Actinomyces viscosus, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia. The results showed a positive indirect immunofluorescence reaction in 24 of the 25 samples. Fourteen were positive for the specie Actinomyces viscosus, 12 for Prevotella intermedia, 10 for Fusobacterium nucleatum and 4 for Porphyromonas gingivalis. A semiquantitative assay was easily implemented for assessment of degree of infection by the organisms in individual cases.  相似文献   

15.
The objective of this study was to compare the sensitivity and specificity of an enzyme immunoassay employing antibodies bound to a microtiter plate (MPEIA) with those of two radioimmunoassays for screening postmortem blood from selected coroner's cases for drugs of abuse. The radioimmunoassays were a coated-tube radioimmunoassay (CTRIA) and a double antibody radioimmunoassay (DARIA). Specimens consisted of 260 postmortem blood specimens from coroner's cases. Immunoassay results (positive or negative) were compared with confirmed results on those cases by gas chromatography-mass spectrometry, alone or in combination with gas-liquid chromatography using either a nitrogen-phosphorus or flame-ionization detector. Sensitivity was calculated as the true-positive rate using chromatographic confirmation as the reference standard. Specificity was calculated as the true-negative rate. Sensitivity and specificity were calculated for 5-7 potential cutoff concentrations for the drug classes opiates, amphetamines, cocaine and metabolites, and barbiturates. For opiates, the sensitivity and specificity were 99% and 93%, respectively, for the MPEIA at a cutoff of 20-ng/mL morphine, compared with 94% and 96% for the CTRIA at a cutoff of 5-ng/mL morphine and > 99% and 96% for the DARIA at 20-ng/mL morphine. For cocaine and metabolites, the sensitivity and specificity were 96% and 93%, respectively, for the MPEIA at 50-ng/mL benzoylecgonine, compared with 93% and 96% for CTRIA at 50-ng/mL benzoylecgonine and 98% and 97% for the DARIA at 50-ng/mL benzoylecgonine. For amphetamines, the sensitivity and specificity were >99% and 91%, respectively, for the MPEIA at 25-ng/mL methamphetamine, compared with 93% and 86% for the CTRIA at 25-ng/mL methamphetamine and 83% and 89% for the DARIA at 50-ng/mL methamphetamine. For barbiturates, the sensitivity and specificity were > 99% and 92%, respectively, for the MPEIA at 50-ng/mL secobarbital, compared with 91% and 87% for the CTRIA at 500-ng/mL secobarbital and 79% and 95% for the DARIA at a cutoff of 1000-ng/mL phenobarbital.  相似文献   

16.
Memory performance for sequences of letters positioned in particular spatial locations in a 3 x 3 grid was examined by requiring participants to recall attributes of the target stimuli given 1 or 2 features of the stimuli as cues. Cuing asymmetry was observed between the serial-position curves of object and sequential-order information, and location and sequential-order information, when the stimuli were presented in both the same and different locations. After correcting for response bias, this asymmetry was attenuated for the stimuli presented in different locations and was eliminated for the stimuli presented in the same location. Contrary to the predictions of the fragmentation hypothesis (G. V. Jones, 1976), asymmetry was also observed between object and location information. The roles of spatial location and response bias are offered as explanations for previous contradictory claims for cuing symmetry between item and order information.  相似文献   

17.
The values of free energies for the formation of hydrophobic cores with different degree of packing of nonpolar side chains have been calculated. It has been shown that the difference between the values of free energy for tightly packed cores inaccessible to water solvent molecules and the values of free energies for less tightly packed hydrophobic cores whose surface is in contact with the water solvent, is 50-60 kJ/mol and coincides with the value of the enzyme free energy change during its interaction with the substrate.  相似文献   

18.
Assessment of Stability of Slopes under Drawdown Conditions   总被引:4,自引:0,他引:4  
The traditional approach for estimating the stability of slopes under different submergence conditions is the charts of Morgernstern and, more recently, proprietary computer programs, both utilizing limit-state analyses. The chart approach is limited by geometry and material property considerations and the limit-state approach by assumptions about analysis method and failure mechanism. The finite-element method offers a powerful method for analyzing complex geometries and properties of slope stability problems, but may be unattractive for routine use by supervisory staff. By comparison a chart based approach is useful, particularly when setting operating conditions on, for example, drawdown rates for dams and reservoirs. This paper seeks to explore the use of the finite-element method to produce operating charts for such circumstances that should be applicable to real structures.  相似文献   

19.
钢水过程热损失主要为钢水的辐射散热,对流传热和钢包、中间包耐火材料的吸热。为了减少钢水的过程温降,相应采取了一系列措施:优化钢包保温层,降低包衬的导热系数,减轻包衬的热损失;对脱氧合金化用合金进行烘烤,提高合金加入钢水前的温度;大包加保温盖,实施全程保护浇注等。改进后,平均出钢温度降低20℃以上。  相似文献   

20.
贾忠  申利斌  常福刚 《宽厚板》2004,10(3):26-28
γ射线测厚仪的补正机能是厚度精确测量的关键,一般对热态钢板进行测量的测厚仪补正机能包括吸收补偿曲线、材质密度补正、温度补偿曲线、相互干涉补正。  相似文献   

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