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451.
452.
NW Hsu JW Chen SL Jen GY Mar WL Lee SP Wang MS Chang 《Canadian Metallurgical Quarterly》1996,58(4):241-247
In this review we survey the features of alcohol-induced lesions in the heart, in both the clinical and laboratory-animal setting. The data indicates a diverse range of lesions that contribute to the genesis of the entity alcoholic cardiomyopathy (also referred to as alcoholic heart muscle disease). Biopsies of affected patients reveal lesions similar to dilated cardiomyopathy though quantitative morphometry can distinguish between the two disorders. Biochemical analysis reveals an increase in the activities of some enzymes, though the pathogenetic nature of these alterations are unknown, but may well be adaptive. The induction of ischaemia in acute ethanol exposure may contribute to the heart muscle damage, though long term experimental studies indicate that heat shock proteins are reduced, making the heart more vulnerable to cardiac dysfunction. Changes in the rate of protein turnover induced by alcohol appear to be a central feature in animal studies and it is very likely that similar changes occur in man. 相似文献
453.
The flow rate of liquid carried on a nylon strand moving from a liquid filled space, through an air filled space, to another liquid filled space was determined from measurements of electrical conductance of the separated liquids. The measurements are consistent with the transmission of a liquid layer on the nylon surface of constant thickness, independent of surface velocity. The layer thickness is low enough that an adsorptive strand can carry adsorbate from a solution at a practical rate. The effective concentration of solution taken from an adsorption chamber by a saturated adsorbent strand is estimated to be at least 5.8 (λ/S) times the chamber concentration, where λ is the chamber length and S the line speed. 相似文献
454.
"It is our purpose… to examine manpower trends in psychiatry, psychology, and social work." Two major problems relating to higher education are: (1) That many bright young people do not receive the training for which they are intellectually competent, and (2) That because of heightened birth rate beginning in the 1940's, a substantial rise in college enrollments can be expected within the next decade. The demand for trained personnel in the field of mental health is considered. Separate sections titled "Psychiatrists," "Psychologists," and "Social Workers" discuss the supply of and need for professional workers within each field. 50-item bibliography. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
455.
H. E. Biber R. C. Takacs A. E. Dickey 《Metallurgical and Materials Transactions B》1983,14(3):369-373
The way in which heating in hydrogen-nitrogen atmosphere affects the pyrolysis of the residual lubricant on cold-reduced steel
sheet was studied to discover the factors responsible for the formation of carbonaceous films on the steel surface. These
films, referred to as insoluble surface carbon, cannot be removed with the usual solvents or water-base cleaners and adversely
affect the paintability of the steel. A surprising result was the observation that the full-hard steel surface has a significant
amount of insoluble surface carbon; amounts in excess of 0.010 gm/m2 (1 mg/ft2) were observed. The origin of this “initial” insoluble carbon can be traced to the pickling operation after hot rolling.
During annealing much of the residual rolling lubricant on the surface is driven off by evaporation, but concurrently insoluble
pyrolysis products are formed. The amount of insoluble pyrolysis product formed is directly related to the amount of “initial”
insoluble carbon on the surface before annealing. The results show that at some point during annealing the total amount of
insoluble carbon on the surface is more than double the amount of “initial” insoluble carbon. These insoluble pyrolysis products
can also be driven from the surface at higher temperatures than are required for evaporation of the oil. The results suggest
that removal of the “initial” insoluble carbon prior to cold reduction might be very beneficial with respect to decreasing
the amount of insoluble carbon on the surface of steel sheet after annealing. 相似文献
456.
NW Levin PM Yang DA Hatch AJ Dubrow NS Caraiani TS Ing VC Gandhi A Alto SM Davila FR Prosl HD Polaschegg J Megerman 《Canadian Metallurgical Quarterly》1998,54(5):1739-1745
A new subcutaneous device (Dialock; Biolink Corp., Middleboro, MA) provides vascular access to patients who currently require hemodialysis (HD). The device consists of a port-like valve, implanted subcutaneously below the clavicle, which provides a linear flow passage to two catheters placed in the right atrium via the jugular vein. The valve is accessed percutaneously with needle-cannulas that functionally convert the device to twin catheters for connecting the patient to the HD lines. Interdialytic patency is maintained using a standard heparin lock. The device has been implanted in 10 outpatients under local anesthesia, with almost immediate use for HD (median, 3 days) and has functioned successfully for more than 6 months (mean +/- SD, 4.0 +/- 1.7; > 400 dialysis sessions). Blood flows over 300 ml/min were consistently achieved (average, 320 +/- 50) with venous and arterial pressures of 197 +/- 42 mmHg and -241 +/- 31 mmHg, respectively. After 40 patient-months, condition of the needle puncture sites remains satisfactory. Four systemic infections have occurred in three patients; all have resolved without the need for device removal. There have been no infections at the puncture sites. One patient whose heparin lock was not changed for 23 days (for reasons unrelated to the device) required fibrin sheath stripping of his catheters. Patient and nurse acceptance has been excellent. The device may offer substantial improvement over conventional devices for HD access. 相似文献
457.
An infusion of etomidate and fentanyl was compared with halothane or morphine plus nitrous oxide in oxygen for the maintenance of anaesthesia in 200 patients. Cardiovascular and respiratory changes were found to be similar in the two groups. There was a prolongation of recovery time in the etomidate-fentanyl group: this was possibly a result of lack of flexibility in the infusion technique. 相似文献
458.
O Bandmann MG Sweeney SE Daniel GK Wenning N Quinn CD Marsden NW Wood 《Canadian Metallurgical Quarterly》1997,49(6):1598-1604
Multiple system atrophy (MSA) is a neurodegenerative disorder of unknown cause. The only case-control study conducted in MSA patients to date suggested a possible contributory genetic component in the pathogenesis of this disorder. The aim of this study was to evaluate a possible overlap between clinically or pathologically well-defined MSA and other conditions with an identified genetic defect causing spinocerebellar degeneration in humans or mutant mice strains. The spinocerebellar ataxia type 1 and 3 genes (SCA1 and SCA3) were analyzed for a pathologic expansion in 80 patients with MSA to evaluate a possible overlap between MSA and SCA1 or SCA3. Weaver mice and lurcher mice are animal models for spinocerebellar degeneration; both share pathologic features with MSA. We sequenced the H5 pore region of the human homologue of the weaver mouse gene, hiGIRK2, in all our patients. In lurcher mice, previous biochemical studies have shown a decreased intracellular response to insulin-like growth factor 1 (IGF-1) in the cerebellar cortex, and we thus investigated the possibility of an allelic association between MSA and the receptor for IGF-1. In addition, we evaluated a possible involvement of the ciliary neurotrophic factor gene (CNTF) and examined the role of HLA-A32 to clarify the conflicting data from previous studies. No changes were detected in any of the analyzed genes. Our studies strongly suggest that MSA is an autonomous syndrome distinct from identified genetic causes for spinocerebellar degeneration. 相似文献
459.
460.
As age and smoking are common risk factors, patients with lung cancer frequently have coexistent ischaemic heart disease. Ignoring the coronary disease results in an unacceptable operative mortality, whilst sequential coronary grafting and lung resection may prejudice the results of the resection. A series of 10 patients underwent combined coronary revascularization (average 2.9 grafts per patient) and lung resection for carcinoma (seven lobectomies, one bilobectomy, one sleeve lobectomy, and one pneumonectomy). The majority of patients had unstable angina, triple vessel or left main coronary artery stenosis and poorly staged tumours. There was no operative mortality and the average hospital stay was 20 days. Half the patients had significant peri-operative morbidity; seven are alive and well at between 12 and 38 months follow-up; but three have died of recurrent carcinoma (one with associated sepsis) at 3, 8, and 13 months. Combined coronary revascularization and lung resection can be safely performed in selected patients. The early morbidity is mainly related to the cardiac procedure and impaired respiratory function preoperatively, but the long-term results are dependent upon the control of the lung carcinoma. 相似文献