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排序方式: 共有666条查询结果,搜索用时 15 毫秒
21.
VI Tselu?ko NA Kravchenko IV Shut' VI Cherkashina 《Canadian Metallurgical Quarterly》1994,28(5):73-77
Restriction fragment length polymorphism of the apo-B gene at the Xbal restriction site was detected. The association between RFLP of the apo-B gene and the level of lipid metabolism indices was revealed. The levels of total cholesterol LDLP CH and atherogenicity coefficient were significantly higher in homozygotes with this restriction site (X2X2) than in homozygotes X1X1 and heterozygotes. 相似文献
22.
OBJECTIVES: As the incidence of prostate cancer in the United States exceeds 330,000 in 1997, increasingly more men are faced with treatment choices for which there is no clear approach. At every stage of disease, these treatment choices may involve clinically equivalent modalities that differ in side effects and impact upon quality of life (QOL). Comprehensive, yet efficient, questionnaires are needed to measure QOL in patients with prostate cancer. METHODS: Developed as a disease-specific adjunct to the Functional Assessment of Cancer Therapy (FACT) measurement system, a 12-item prostate cancer subscale (PCS) was developed and tested in three independent samples: a subscale development sample (n = 43), validity sample 1 (n = 34), and validity sample 2 (n = 96). The 12 items ask about symptoms and problems specific to prostate cancer. These questions are added to the general (FACT-G) instrument, thereby comprising a 47-item questionnaire. RESULTS: Internal consistency of the PCS ranged from 0.65 to 0.69, with coefficients for FACT-G subscales and aggregated scores ranging from 0.61 to 0.90. Concurrent validity was confirmed by the ability to discriminate patients by disease stage, performance status, and baseline prostate-specific antigen (PSA) level. Sensitivity to change in performance status and PSA score over a 2-month period suggested that some subscales of the FACT-Prostate (P) (including the PCS) are sensitive to meaningful clinical change. CONCLUSIONS: Our findings support use of the FACT-P as a meaningful component of QOL evaluation in men undergoing therapy for prostate cancer. 相似文献
23.
IuG Suchkov IV Khudiakov EN Emel''ianenko MI Levi VI Pushkareva IIu Suchko VIu Litvin EV Kulesh RS Zotova AL Gintsburg 《Canadian Metallurgical Quarterly》1997,17(4):42-46
The purpose of this study was to find criteria characteristic for patients in need of care and social services. The criteria should serve as a guideline for patients and staff to facilitate care planning before discharge. The sample consisted of 49 patients, born before 1925, in need of emergency inpatient treatment, admitted to medical- or orthopaedic wards. Data of the patient's self care needs were collected by interviews, assessment of self care status and need of treatment. The patients could be divided into three groups depending on type of discharge. Group A (n = 27) discharged home, group B (n = 7) discharged to geriatric clinic and group C (n = 15) discharged and in need of further care and social services. Criteria indicating the patients further assistance from the community were in group C (medical- and orthopaedic wards) deficit in daily living activities and locomotion. Group B had an increased need of support from the physiotherapist and the occupational therapist, in locomotion as well as daily living activities The physician's assessment showed that the criteria behind the decision "no further medical treatment appropriate" and "ready for discharge" were not related to medical impairment but to lack of self care, need of care, rehabilitation and social services. 相似文献
24.
The vigilance reaction is characterized by a large bradycardia, a pressor response, and inspiratory apnea in anesthetized rabbits and the inhibition of movement in conscious rabbits. This affective response pattern can be elicited by electrical stimulation of the dorsolateral hypothalamus (the hypothalamic vigilance area) or the ventrolateral periaqueductal gray (the periaqueductal gray vigilance area). The present study sought to advance our understanding of the functional relationship between the hypothalamic vigilance area (HVA) and the periaqueductal gray vigilance area (PVA) by measuring the effects of transverse transections of the caudal portion of the ventrolateral PAG (vlPAG) upon the cardiovascular responses elicited from the dorsolateral hypothalamus and the rostral vlPAG. Selective transverse transections of the caudal vlPAG significantly reduced the magnitudes of the bradycardia and pressor response elicited by stimulation of the PVA rostral to the transection site, but had minimal impact on the cardiovascular responses evoked by stimulation of the HVA. These findings suggest that the cardiovascular responses elicited by stimulation of the vlPAG are mediated by a neural pathway that is parallel, at least in part, to the one that subserves the response elicited from the HVA. The results also provide support for the view that the PAG is not an essential structure in the mediation of the autonomic components of affective behaviors involving behavioral inhibition. 相似文献
25.
Dentists are often called upon to perform painful procedures on children. This may present a management problem for the practitioner who is unfamiliar with accepted behavioural management techniques or prescribing analgesics for paediatric patients. This article will review techniques that may be used to guide a child patient's behaviour through painful procedures as well as addressing the need for post-operative analgesics in the paediatric population. 相似文献
26.
IV Ga?voronski? LP Tikhonova SV Chepur GI Nichiporuk 《Canadian Metallurgical Quarterly》1997,112(6):33-37
An original quantitative examination of oxidation-reduction enzymes activity in endotheliocytes of hemomicroclrculatory vessels of jejunum and rectum submucosal base in normal state and in portal hypertension was performed by the authors. Comparative analysis of the activity of the enzymes studied revealed different metabolic processes intensity in these organs, dependent on current hemodynamic conditions. Cytochemical changes in hemomicrocirculatory bed are consistent with structural reorganizations that arise in the wall of vessels studied, consist of several phases and may be used as an assessment criterion for defining the portal hypertension stage. 相似文献
27.
Monoterpenes such as limonene and perillyl alcohol (PA) are currently under investigation for their chemotherapeutic properties which have been tied to their ability to affect protein isoprenylation. Because PA affects the synthesis of isoprenoids’ such as ubiquinone’ and cholesterol is the end product of the synthetic pathway from which this isoprenoid pathway branches’ we investigated the effects of this compound upon cholesterol metabolism in the colonic adenocarcinoma cell line SW480. PA (1 mM) inhibited incorporation of 14C-mevalonate into 21–26 kDa proteins by 25% in SW480 cells. Cholesterol (CH) biosynthesis was assessed by measuring the incorporation of 14C-acetate and 14C-mevalonate into 27-carbon-sterols. Cells treated with PA (1 mM) exhibited a fourfold increase in the incorporation of 14C-acetate but not 14C-mevalonate into cholesterol. Mevinolin (lovastatin)’ an inhibitor of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase’ at 2 μM concentration’ inhibited CH synthesis from 14C-acetate by 80%. Surprisingly’ concurrent addition of mevinolin and PA did not significantly alter the stimulatory effects of PA. As observed differences in 14C-acetate and 14C-mevalonate precursor labeling could indicate PA affects early pathway events’ the effects of this monoterpene on HMG-CoA reductase activity were evaluated. Unexpectedly’ 1 mM PA did not stimulate activity of this enzyme. Consistent with its action as a reversibly bound inhibitor’ in washed microsomes’ 2 μM mevinolin pretreatment increased reductase protein expression causing a 12.7 (±2.4)-fold compensatory HMG-CoA reductase activity increase; concurrent treatment with 1 mM PA attenuated this to a 5.3 (±0.03)-fold increase. Gas chromatographic analysis confirmed CH was the major lipid present in the measured thin-layer chromatography spot. Since 14C-acetate incorporation into free fatty acid and phospholipid pools was not significantly affected by PA treatment’ nonspecific changes in whole acetate pool sizes were not indicated. Because increases in endogenous CH synthesis should result in compensatory changes in exogenous sterol utilization’ the effects of PA upon low density lipoprotein (LDL) receptor activity were evaluated. Consistent with the observed increases in CH synthesis’ 1 mM PA decreased 125I-LDL internalization to 50% of the fetal bovine serum control; concurrent addition of 2 μM mevinolin attenuated this effect to a reduction of 80% of the control value. Data suggest that in certain colonic tumor cells PA strongly affects cholesterol metabolism via a mechanism of action that is insensitive to the HMG-CoA reductase inhibitor mevinolin. 相似文献
28.
The quantity, extraction efficiency, and molecular composition of non-volatile oligomeric species in SOA generated by the reaction of α-pinene with ozone were studied. Two different methods of determining the total particulate mass in the reaction chamber were compared and found to be in good agreement when changes in the partitioning of semi-volatile compounds to the particle phase during measurement were properly handled. Almost all of the non-volatile organic carbon formed by the reaction was collected and recovered by extraction with organic solvents; recoveries with water extraction were somewhat lower. The identities of compounds extracted by the various solvents were determined using electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry. Over 80% of the peaks weighted by mass and intensity were the same in the spectra of samples obtained from different extraction solvents. Standard addition plots were used to determine the amounts of two commercially available monomer compounds in the SOA extracts. When the response factors for those compounds were applied to other monomers detected in the mass spectra, the weight percent of monomers was estimated to be slightly less than 50%, with the remaining mass (over 50%) assigned to oligomers. The oligomer content is sufficiently large that it should be taken into account when modeling the formation and properties of laboratory SOA. 相似文献
29.
Abstract The height equivalent to a theoretical stage (HETS) is estimated using one correlation to describe behavior for reciprocating speeds below the optimum point and a second expression to estimate HETS values for reciprocating speeds above it. These two equations are then combined to yield a generalized expression that is applicable in both regions and which can be used to predict the minimum HETS and the optimum reciprocating speed. The observed dependence on the operating parameters and the physical properties of the liquid/liquid system generally agree with those observed in HETS correlations for pulse columns. 相似文献
30.
The use of complex materials, such as composites, for fabrication of structural components exacts a price of increased complexity in design and analysis of these structures. In order to economically and efficiently facilitate complex structural design and analysis, computer-aided design techniques are being employed throughout the industrial community. This paper illustrates a system of computer-aided design techniques and software (CADOT) for the design and analysis of engineering structures and solids that are constructed of sheet molding, injection molding, and/or laminated composite technologies. 相似文献