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61.
Rats, deficient in essential fatty acids (EFA), were given diets containing 5 energy% sunflowerseed oil (SO, rich in linoleic acid), cod-liver oil (CLO, rich in timnodonic acid and cervonic acid), or hydrogenated coconut oil (HCO), containing no EFAs at all. SO and CLO feeding resulted in normalization of the reduced arterial thrombus formation in EFA-deficient animals. SO feeding was associated with the normalization of the arachidonic acid content of platelet phospholipids. CLO feeding did not have this effect but greatly increased the availability of timnodonic acid (EPA) and cervonic acid (DHA). Further research is required to investigate whether these changes in fatty acid composition can be hold responsible for the normalizing effect of dietary CLO on the disturbed arterial thrombosis tendency in EFA deficient rats, possibly via the formation of eicosanoids.  相似文献   
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Differences that emerge in comparisons of persons applying for psychiatric care at a mental health center with those applying to the private sector are comfounded by marked diagnostic differences beyond obvious social class differences. To circumvent that problem and to ascertain what differences, if any, persist after diagnosis is held constant, the authors examined demographic and psychosocial characteristics of neurotics in a one-year adult applicant population, the only major diagnostic group treated in large numbers and similar proportions by the center and the private sector. Findings showed that significantly more neurotic applicants in the private sector are medical referrals, are members of intact nuclear families, and do not have previous inpatient experience.  相似文献   
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Light and ultramicroscopical features of spontaneous glomerular lipoidosis are described. The affected glomeruli showed eosinophilic foamy transformation of part or the whole of a glomerulus. There was deposition of lipoid material and lipofuscin. In ultramicroscopical studies the foamy cells were found to be mainly altered mesangial cells. In addition, endothelial cells with minor cytoplasmic vacuolation and globular inclusions were found. The lesion was unassociated with the inflammatory cell infiltration or proteinaceous plaque deposition which has been described in various pathological glomerular nephropathies. The cause was not established. Spontaneous glomerular lipoidosis of dogs is a distinct entity unrelated to glomerulonephritis and unassociated with any functional impairment.  相似文献   
66.
Many social animals vocalize at high rates, suggesting that vocal communication is highly motivated and rewarding. In songbirds, much is known about the neural control of vocal behavior; however, little is known about neurobiological mechanisms regulating the motivation to communicate. This study examined a possible role for opioid neuropeptides in motivation and reward associated with song production in male European starlings (Sturnus vulgaris). Peripheral opioid blockade facilitated male song production. Furthermore, methionine-enkephalin immunolabeled fiber densities within brain regions in which opioids are known to regulate motivation and reward (i.e., the medial preoptic nucleus and ventral tegmental area) related positively to male song production. These data suggest that song production might be regulated by opioid activity within motivation and reward neural systems.  相似文献   
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68.

Background

Cigarette smoking is the most well-established risk factor for developing bladder cancer.

Objective

To investigate the role of smoking status on the clinical outcome of patients with non-muscle-invasive bladder cancer.

Design, setting, and participants

Data obtained during a prospective phase 3 study with three schedules of epirubicin were used for statistical analysis. Smoking status (obtained when entering the study), other prognostic variables, and clinical outcome measures of 718 patients were analyzed. Mean follow-up was 2.5 yr.

Measurements

The primary outcome measure was recurrence-free survival (RFS).

Results and limitations

Demographics were similar for nonsmokers versus ex-smokers and current smokers, except for gender (p < 0.001) and grade (p = 0.022). In univariate analyses, RFS was significantly shorter in male patients (p = 0.020), in patients with a history of recurrences (p < 0.003), in patients with multiple tumors (p < 0.004), in patients with a history of intravesical therapy (p = 0.037), and in ex-smokers and current smokers (p = 0.005). In multivariate analyses, a history of recurrences, multiplicity, and smoking status remained significant factors for predicting RFS. Gender and initial therapy were no longer a significant influence on RFS.Because progression was uncommon (n = 25) and follow-up was short and focused only on recurrences, no conclusion can be drawn on progression-free survival. A limitation of the study were the questionnaires. They were only used when entering the study, and there were no questions about passive smoking and other causal factors.

Conclusions

In this prospective study, the significance of known factors (history of recurrences and number of tumors) in predicting RFS was confirmed. Another significant factor that appears to predict RFS is smoking status: ex-smokers and current smokers had a significantly shorter RFS compared with nonsmokers.  相似文献   
69.
Implementation of multiplex ligation-dependent probe amplification (MLPA) for thalassemia causing deletions has lead to the detection of new rearrangements. Knowledge of the exact breakpoint sequences should give more insight into the molecular mechanisms underlying these rearrangements, and would facilitate the design of gap-PCRs. We have designed a custom fine-tiling array with oligonucleotides covering the complete globin gene clusters. We hybridized 27 DNA samples containing newly identified deletions and nine positive controls. We designed specific primers to amplify relatively short fragments containing the breakpoint sequence and analyzed these by direct sequencing. Results from nine positive controls showed that array comparative genomic hybridization (aCGH) is suitable to detect small and large rearrangements. We were able to locate all breakpoints to a region of approximately 2 kb. We designed breakpoint primers for 22 cases and amplification was successful in 19 cases. For 12 of these, the exact locations of the breakpoints were determined. Seven of these deletions have not been reported before. aCGH is a valuable tool for high-resolution breakpoint characterization. The combination of MLPA and aCGH has lead to relatively cheap and easy to perform PCR assays, which might be of use for laboratories as an alternative for MLPA in populations where only a limited number of specific deletions occur with high frequency.  相似文献   
70.

Objective

Digital mammography has been shown to increase the detection of ductal carcinoma in situ (DCIS) compared to screen-film mammography. The benefits and risks of such an increase were assessed.

Methods

Breast cancer detection rates were compared between 502,574 screen-film and 83,976 digital mammograms performed between 2004 and 2006 among Dutch screening participants. The detection rates were then modeled using a baseline model and two extreme models that respectively assumed a high rate of progression and no progression of preclinical DCIS to invasive cancer. With these models, breast cancer mortality and overdiagnosis were predicted.

Results

The DCIS detection rate was significantly higher at digital mammography (1.2 per 1000 mammograms (95% C.I. 1.0-1.5)) than at screen-film mammography (0.7 per 1000 mammograms (95% C.I. 0.6-0.7)). Consequently, 287 (range progressive- non progressive model: 1-598) extra breast cancer deaths per 1,000,000 women (a 4.4% increase) were predicted to be prevented. An extra 401 (range: 165-2271) cancers would be overdiagnosed (a 21% increase).

Conclusion

Modeling predicted that digital mammography screening would further reduce breast cancer mortality by 4.4%, at a 21% increased overdiagnosis rate. The consequences of digital screening, however, are sensitive to underlying assumptions on the natural history of DCIS.  相似文献   
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