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21.
We examined the relations between sociotropy and autonomy and clinical features of depression. A. T. Beck (1983) proposed that sociotropy is related to a sense of deprivation and clinical features associated with reactive depression and that autonomy is related to a sense of defeat and clinical features associated with endogenous depression. C. J. Robins et al (see record 1989-19204-001) found support for the hypothesis for sociotropy but not for autonomy, and they suggested that the autonomy scale may be problematic. We administered new measures of sociotropy and autonomy and a more comprehensive assessment of clinical features to 50 unipolar depressed inpatients. The results support the selective relations of both sociotropy and autonomy to the predicted sets of clinical features. This study adds to the growing evidence that these personality dimensions are important to the understanding of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered.  相似文献   
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Response of adults of the West Indian sugarcane weevil,Metamasius hemipterus sericeus, to various semiochemical treatments and physical trap designs was studied in southern Florida in field-grown banana and Canary Island date palms. Ethyl acetate released alone at 860–1007 mg/day was as effective for the capture ofM. h. sericeus as a combination of ethyl acetate (844–919 mg/day), ethyl propionate (348–362 mg/day), and ethyl butyrate (117–137 mg/day) and in one trial was more effective than fermenting sugarcane (250 g), ethyl propionate alone (353–384 mg/day), ethyl butyrate alone (123–174 mg/day), or no treatment. Ethyl acetate released alone at 675–683 mg/day was as attractive as 250 g of fermenting sugarcane or the racemic blend of the male-produced aggregation pheromones [(±)-5-methyl-nonan-4-ol and (±)-2-methyl-heptan-4-ol (8:1 ratio) “metalure”] at 3 mg/day. Weevil counts increased with binary combinations of ethyl acetate, sugarcane, and/or metalure over these treatments alone and the ternary combination was two to three times more effective than any of the binary treatments. Attraction to ethyl acetate released alone at 777 mg/day with metalure was greater than to the hydrolysis products of ethyl acetate (ethanol and/or acetic acid each released at about 6–8 mg/day) with metalure. Weevil counts from traps baited with 250 g of sugarcane and metalure increased with increasing dose of ethyl acetate to about 400 mg/day and then appeared to plateau. Ethyl acetate (about 700 mg/day) and metalure increased weevil counts in traps with increasing amounts of sugarcane (0–2 kg). Molasses (45 g) + water (158 ml) substitutes for sugarcane were about as effective for capturingM. h. sericeus as 250 g of fermenting sugarcane [all treatments with ethyl acetate (847 mg/day) and metalure]. Early experiments used a lethal pitfall trap. We demonstrated that several alternative trap designs were more effective than the lethal pitfall trap for capturing weevils. Color and height (on ground vs. 1 m on pole) did not affect trap efficacy when baited with the ternary combination of ethyl acetate (672–825 mg/day), sugarcane (250 g), and metalure.  相似文献   
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We have verified that chemotaxis of isolated human polymorphonuclear leukocytes (PMN) was a target of in vitro toxicant effect of acrylonitrile (ACN). This toxicant induced a significant dose dependent decreasing of chemotaxis with 50% inhibition (IC50) occurring at 15 mM. We assume that PMN from workers exposed to ACN reacts vivo in a similar way to PMN exposed in vitro to ACN. We propose therefore to use chemotaxis assay as a biomarker of early biological effect of ACN in workers, since for their monitoring there are so far only internal dose indicators but no suitable effect indicators.  相似文献   
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OBJECTIVE: Percutaneous transluminal angioplasty of stenoses of the renal artery can be used to treat hypertension and renal insufficiency. Although many studies have been published on the short-term results of this procedure, few long-term studies are available. SUBJECTS AND METHODS: One hundred ninety-five patients (123 men and 72 women 19-79 years old; mean age, 56 years) with stenosis of the renal artery and hypertension underwent renal percutaneous transluminal angioplasty at our institution. The stenosis was unilateral in 66% of patients, bilateral in 26%, and in a solitary functioning kidney in 8%. Renal insufficiency was present in 31% of patients. After renal percutaneous transluminal angioplasty, long-term clinical and angiographic follow-up was evaluated by life-table analysis. RESULTS: In patients with fibromuscular disease, blood pressure returned to normal in 57%, improved in 21%, and was unchanged in 21%. In patients with atherosclerotic stenosis, blood pressure returned to normal in 12%, improved in 51%, and was unchanged in 37%. After percutaneous transluminal angioplasty, renal function improved in 48% of patients with renal insufficiency due to bilateral stenosis or stenosis in the single functioning kidney, whereas none of the patients with unilateral stenosis of renal artery and renal insufficiency had any notable improvement. Long-term follow-up showed a high rate (82%) of patency of revascularized arteries and a low rate (21%) of hypertension recurrence at 5 years. CONCLUSION: Renal percutaneous transluminal angioplasty is useful for treating hypertension and for reestablishing renal function. Its effects on blood pressure and renal function are long-lasting in the large majority of patients.  相似文献   
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Experimental results for an integrated-optical state-of-polarisation (SOP) controller device on Ti:LiNbO3 for continuous broadband optical operation, with small temperature sensitivity and the possibility of integration with polarisation- insensitive directional couplers, are presented.  相似文献   
29.
Increased Ca2+ signal generation may lead to hyperactivity of platelets and contribute to thrombotic complications. Using fura-2-loaded platelets from 51 healthy volunteers, high variability was detected in the Ca2+ responses evoked by the receptor agonists, thrombin and collagen, and the inhibitor of sarco/endoplasmic reticulum Ca2+-ATPases (SERCA), thapsigargin (Tg). Oral intake of 500mg aspirin reduced the magnitude of the Ca2+ responses, and lowered the intra-individual coefficients of variance of the responses by 50%. However, the corresponding inter-individual variance coefficients were only a little influenced by aspirin intake, pointing to subject-dependent factors in Ca2+ handling that are unrelated to thromboxane formation. With each agonist, 6-9% of the subjects had platelets with relatively high Ca2+ responses (> mean + SD) both before and after aspirin intake. In 90% (9/10) of these cases the high responsiveness was confirmed in platelets obtained 6-12 months later. The Tg- but not thrombin-induced Ca2+ responses correlated inversely with the expression levels of SERCA PL/IM 430 (SERCA-3b) in platelets. After aspirin intake, the Ca2+ responses with collagen but not thrombin correlated inversely with SERCA-2b expression. These results suggest that, in the absence of potentiating effects of thromboxane, (i) the amount of PL/IM 430-recognizable SERCA may control the Ca2+ signal when SERCA-2b is specifically inhibited (with Tg), and (ii) the expression of SERCA-2b determine the collagen- but not the thrombin-evoked Ca2+ signal. Accordingly, limited Ca2+-pumping activity by low expression of one of the SERCA isoforms is likely to be one of the factors resulting in increased platelet activity towards collagen or thapsigargin but not thrombin.  相似文献   
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The development of potent antitumor agents with a low toxicological profile against healthy cells is still one of the greatest challenges facing medicinal chemistry. In this context, the “mutual prodrug” approach has emerged as a potential tool to overcome undesirable physicochemical features and mitigate the side effects of approved drugs. Among broad-spectrum chemotherapeutics available for clinical use today, 5-fluorouracil (5-FU) is one of the most representative, also included in the World Health Organization model list of essential medicines. Unfortunately, severe side effects and drug resistance phenomena are still the primary limits and drawbacks in its clinical use. This review describes the progress made over the last ten years in developing 5-FU-based mutual prodrugs to improve the therapeutic profile and achieve targeted delivery to cancer tissues.  相似文献   
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