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211.
212.
Tarrier Nicholas; Barrowclough Christine; Ward Jonathan; Donaldson Catherine; Burns Alistair; Gregg Lynsey 《Canadian Metallurgical Quarterly》2002,111(2):340
Burden of care, expressed emotion (EE), causal attributions, and salivary cortisol were assessed in 100 carers of patients with Alzheimer's disease. Forty-one carers were rated high EE, which was associated with higher scores of carer distress and strain, and greater reports of noncognitive features in the patient, but not with cortisol levels. High EE carers made more attributions personal to, and controllable by, the patient for negative events. Critical carers made more attributions of the patient's behavior that was idiosyncratic. Warmth toward the patient was associated with the opposite of this pattern. Overinvolved carers made attributions of the patient's behavior to causes external to the patient and internal to themselves. Cortisol levels were associated with self-reports of strain and distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
213.
The Minnesota Multiphasic Personality Inventory (MMPI) was administered to 72 female and 51 male outpatients, and subjects were rated on the Brief Psychiatric Rating Scale. Raw scores on Masculinity–Femininity (Mf) correlated positively with ratings of emotional distress, even with gender effects removed. Male and female patients who scored high (feminine direction) on Mf were rated higher on anxiety, depressed mood, guilt feelings, and tension than were low scorers. Mf was the only MMPI scale to correlate significantly with guilt feelings, and its relationships with anxiety, depressed mood, and tension were largely independent of other MMPI clinical scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
214.
BACKGROUND: Traditionally, patients presenting with uncomplicated dyspepsia have been managed using empiric antisecretory therapy, followed by endoscopy in the event of persistent symptoms or complication. Since Helicobacter pylori is now accepted as an important and potentially reversible cause of ulcer disease, it is important to reevaluate the management of dyspepsia. The goal of this study is to evaluate seven outpatient strategies for the management of dyspeptic patients using a cost-utility analysis. METHODS: The study design was that of a cost-utility analysis. The model assumes that an adult patient with signs of dyspepsia but no signs of complication presents to the outpatient office of a primary care physician. Seven strategies are modeled: empiric antisecretory therapy; empiric H pylori eradication using oral omeprazole (20 mg [corrected] twice daily), clarithromycin (500 mg twice daily), and amoxicillin (1000 mg twice daily); use of either upper endoscopy, an upper gastrointestinal barium study (an upper GI), or the serum titer for H pylori as a diagnostic test to identify patients for H pylori eradication; or use of an initial diagnostic test followed by the serum titer for H pylori. The primary outcome was the cost per quality-adjusted life year (QALY) for each strategy for a 1-year period from presentation; secondary outcomes included the probability of symptomatic ulcer recurrence, cost per ulcer cure, and mortality. RESULTS: Three strategies were similarly cost-effective: empiric H pylori eradication ($1198 per QALY), use of a serum H pylori titer as an initial diagnostic test ($1214 per QALY), and empiric antisecretory therapy ($1288 per QALY). Empiric antisecretory therapy, however, was associated with significantly more symptomatic ulcer recurrences and deaths than any other strategy. CONCLUSIONS: This cost-utility analysis suggests that two strategies are reasonable for patients presenting with dyspepsia: (1) empiric H pylori eradication and (2) use of a serum H pylori titer to identify patients who might benefit from H pylori eradication. The latter strategy may be preferable because it is less likely to lead to antibiotic resistance. Strategies utilizing an upper GI or upper endoscopy (either with or without serum H pylori titer) or empiric antisecretory therapy do not improve outcomes and are associated with greater cost, morbidity, and/or mortality. 相似文献
215.
Mulder J. Ward C.M. Chi-Hung Lin Kruse D. Westra J.R. Lugthart M. Arslan E. van de Plassche R.J. Bult K. van der Goes F.M.L. 《Solid-State Circuits, IEEE Journal of》2004,39(12):2116-2125
This paper presents an 8-b two-step subranging analog-to-digital (ADC) using interpolation, averaging, offset compensation, and pipelining techniques to accomplish an effective number of bits of 7.6 b at 125 MSample/s. The 0.13-/spl mu/m CMOS ADC occupies 0.09 mm/sup 2/ and consumes 21 mW. 相似文献
216.
Arterial thrombi are primarily composed of platelets. Platelets are bound to injured endothelial cells, sub-endothelial matrices, and other platelets by a range of adhesive proteins. Some of these reactions are governed by shear forces. The role of adhesive proteins in the pathogenesis of arterial thrombosis is not fully understood. The aim of this study was to examine the involvement of von Willebrand factor (vWF), fibrinogen (Fg), and fibronectin (FN) in the formation of microvascular thrombi in vivo using a helium-neon laser-induced thrombosis method. Transmission electron microscopy demonstrated that laser irradiation resulted in platelet-rich thrombosis in arterioles and venules, and revealed that this occurred in the absence of endothelial denudation. The mean wall shear rates in mesenteric arterioles and venules were 641 +/- 40 and 280 +/- 20 s-1, respectively. Shear rates increased approximately fivefold in arterioles and tenfold in venules during the formation of occlusive thrombi. Antibody to vWF inhibited thrombosis in arterioles and venules. Antibodies to Fg and FN inhibited thrombosis in venules but not in arterioles. These results confirm that vWF, Fg and FN were involved in thrombogenesis in vivo and demonstrated that significantly higher shear rates were required for the reactions involving vWF than those involving either Fg or FN. 相似文献
217.
T Kuukasj?rvi M Tanner S Pennanen R Karhu OP Kallioniemi J Isola 《Canadian Metallurgical Quarterly》1997,150(4):1465-1471
Ductal carcinoma in situ (DCIS) is considered a direct precursor of invasive ductal breast cancer (IDC). We combined tissue microdissection and comparative genomic hybridization to identify genetic changes in five DCIS lesions with no invasion and in two that were adjacent to IDC. Extensive genetic changes characterized pure DCIS cases with gains of 1q, 6q, 8q, and Xq as well as losses of 17p and chromosome 22 being most often involved. Except for the Xq gain, these changes are also common to IDC. Separate analysis of DCIS and IDC components in the same tumor revealed an almost identical pattern of genetic changes in one case, whereas substantial differences were found in another. We conclude that many of the common genetic changes in IDC may take place before development of invasive growth. However, a simple linear progression model may not always account for the DCIS-IDC transition. 相似文献
218.
Highly consistent quality and cost-effective manufacture of advanced composites can be achieved through automation. It may therefore open up new markets and applications for composite products in aerospace, automotive, renewable energy, and consumer goods. Automated Tape Laying (ATL) and Automated Fibre Placement (AFP) are the two main technologies used to automate the layup of prepreg. The historical development and past research of both technologies is reviewed; with an emphasis on past issues in application and capability as well as their solution, including both thermoset and thermoplastic material layup. It is shown that past developments have moved away from simply emulating manual layup into the now unique layup procedures for ATL, and into the current AFP technology base. The state of the art for both technologies is discussed and current gaps in the understanding of both processes highlighted. From this, future research needs and developments are derived and discussed. 相似文献
219.
LD Boada L Fernández M Zumbado OP Luzardo R Chirino BN Díaz-Chico 《Canadian Metallurgical Quarterly》1996,279(3):1123-1129
Male rat liver microsomes contain a [3H]dexamethasone binding site, capable of binding glucocorticoids and progesterone. We have shown previously that the 17 alpha-alkylated androgen, stanozolol, can inhibit the [3H]dexamethasone binding to microsomes through a negative allosteric mechanism, which gives rise to the possibility of its interaction with a different binding site. In this study, the existence of a single-saturating binding site, capable of binding the radioactive steroid with a maximum number of the specific binding site of 49 +/- 2 pmol/mg of protein and a Kd of 37 +/- 1.3 nM was demonstrated by using [3H]stanozolol. In competition experiments, only stanozolol and danazol were able to compete with [3H]stanozolol for its binding to microsomes, among more than 60 steroids and other compounds tested. The binding of [3H]stanozolol was depressed after protease treatment of the microsomes, or after the administration of cycloheximide to adult male rats for 24 hr, which suggest its proteic nature. The [3H]stanozolol binding site was detected in many tissues of the rat, with the highest concentrations being found in the liver. It was detected from birth, increasing afterward in concentration and reaching a peak at 2 to 3 months of age. This is the first experimental verification of the existence in liver microsomes of a specific binding site for some 17 alpha-alkylate androgens, such as stanozolol and danazol, different from the androgen receptor or the [3H]dexamethasone binding site. 相似文献
220.
Symmetric extension is explored as a means for constructing nonexpansive reversible integer-to-integer (ITI) wavelet transforms for finite-length signals. Two families of reversible ITI wavelet transforms are introduced, and their constituent transforms are shown to be compatible with symmetric extension. One of these families is then studied in detail, and several interesting results concerning its member transforms are presented. In addition, some new reversible ITI structures are derived that are useful in conjunction with techniques like symmetric extension. Last, the relationship between symmetric extension and per-lifting-step extension is explored, and some new results are obtained in this regard. 相似文献