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91.
Human faces are ecologically-salient stimuli. Face sex is particularly relevant for human interactions and face gender recognition is an extremely efficient cognitive process that is acquired early during childhood. To measure the minimum information required for correct gender classification, we have used a pixelation filter and reduced frontal pictures (28,672 pixels) of male and female faces to 7168, 1792, 448 and 112 pixels. We then addressed the following questions: Is gender recognition of male and female faces equally efficient? Are male and female subjects equally efficient at recognising face gender? We found a striking difference in categorisation of male and female faces. Categorisation of female faces reduced to 1792 pixels is at chance level whereas categorisation of male faces is above chance even for 112 pixel images. In addition, the same difference in the efficiency of categorisation of male and female faces was detected using a Gaussian noise filter. A clear sex difference in the efficiency of face gender categorisation was detected as well. Female subject were more efficient in recognising female faces. These results indicate that recognition of male and female faces are different cognitive processes and that in general females are more efficient in this cognitive task.  相似文献   
92.
OBJECTIVES: To evaluate the degree of QT dispersion in a group of young women in the starvation phase of anorexia nervosa (AN) and its relation to left ventricular (LV) mass. STUDY DESIGN: Sixteen patients with self-induced starvation were matched with 16 women of normal weight and 16 constitutionally thin women (body mass index <20 kg/m2). Starving patients and control patients underwent an electrocardiogram and echocardiogram. QT intervals were measured from surface electrocardiograms and QT dispersion was defined as the difference between maximum QT and minimum QT occurring in any of the 12 leads. RESULTS: LV-chamber mass was significantly less in women with AN than in thin and normal-weight women. QT dispersion was significantly greater in AN than in the thin and control groups (QT dispersion: 50 +/- 14 vs 34 +/- 9 and 37 +/- 11 ms, P <.001; QT interval dispersion corrected for heart rate: 49+12 vs 34 +/- 9 and 36 +/- 7 ms, P <.01, respectively). A significant relation between QT dispersion and LV-mass index (r = -0.726, P <.01), and between QTc dispersion and LV mass index (r = -0.693, P < 0.01) were found only in the patients with AN. CONCLUSION: Starving patients show an increased QT dispersion related to reduced LV mass. This result could represent a useful indicator of arrhythmic risk and sudden death in AN.  相似文献   
93.
Several papers have shown that in young people sports activity is associated with a higher prevalence of cardiac valves incompetence, that can be detected, though to a lesser extent, even in healthy subjects randomly selected from the population. Aim of the present study was to analyse the effects of physical activity not only in young subjects but even in the elderly, with particular reference to valve competence, by using the Echo-Color-Doppler. The study cohort was represented by 80 healthy young subjects, 40 men and 40 women, aged between 20 and 25 years, each group subdivided into two subgroups, sedentary and non sedentary, and 80 healthy elderly subjects, 40 men and 40 women, aged between 65 and 91 years, again divided into sedentary and non sedentary. Valve incompetence was more frequent in the elderly if compared to young subjects (P<0.001) and in non sedentary if compared to sedentary subjects (P<0.01), while no significant difference was found between males and females. Worth of interest the fact that in young subjects valve incompetence was more frequent in non sedentary if compared to sedentary subjects (P<0.001), while in the elderly no significant difference was found between sedentary and non sedentary subjects. This original datum may be explained both by the natural higher prevalence of valve incompetence in the elderly, and by the kind of physical activity usually performed by the elderly, i.e. endurance activity.  相似文献   
94.
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96.
Diversity and evolution of the envelope gene of dengue virus type 1   总被引:11,自引:0,他引:11  
The genetic diversity and phylogenetic relationships of a collection of strains of dengue virus type 1 (DV-1), isolated from different parts of the world, were investigated. Phylogenetic trees derived from the complete sequence of the E gene of 44 strains suggested the existence of five genetic types defined by a maximum nucleotide divergence within each group of 6%. The 22 strains from America were classified into a single genetic type that included strains associated either with classical dengue or hemorrhagic dengue episodes. Using a maximum likelihood procedure based on a single rate with dated tips model and substitution rates calculated at the third codon position, evolution of the five DV-1 genotypes was shown to conform to a molecular clock. The average rate of evolution was estimated to be approximately 16.2 x 10(-4) substitutions/third codon position site/year. Using this estimate, divergence among the DV-1 genotypes was calculated to have occurred approximately 100 years ago. Very low average value of the ratio of nonsynonymous-to-synonymous nucleotide substitutions, relative to the respective sites (0.046), indicated that the evolution of the E gene of the DV-1 is subject mostly to purifying selection.  相似文献   
97.
Frigeri C  Tsao J  Cordova M  Schimmer BP 《Endocrinology》2002,143(10):4031-4037
ACTH resistance in mutant derivatives of the Y1 mouse adrenocortical tumor cell line results from a defect that affects the activity of steroidogenic factor-1 (SF1), thereby preventing the expression of the melanocortin-2 receptor. In this report, we show that the SF1 genes in ACTH-resistant mutants differ from the gene in ACTH-responsive Y1 cells by two base changes-one that changes an Ala to Ser at codon 172, and one in the third position of codon 3 that does not affect the protein sequence. Furthermore, several of the mutants contain multiple copies of this alternate SF1 gene (SF1(S172)) on acentric chromosome fragments. The SF1(S172) allele represents a polymorphism rather than a spontaneous mutation because the two SF1 alleles can be traced to the hybrid mouse strain (C57L/J x A/HeJ) from which the original adrenal tumor was derived. The SF1(A172) allele also is found in C57Bl/6J and C57Bl/10J mice, whereas the SF1(S172) allele also is found in C3H/HeJ and DBA/2J mice. The two forms of SF1 had only modest differences in activity suggesting that the SF1 polymorphism per se is not directly responsible for ACTH resistance. Our results indicate that the SF1(S172) allele is a marker of ACTH resistance in this family of adrenocortical tumor cells.  相似文献   
98.
Erectile dysfunction is a recognized complication of prostate and bladder radical surgery, although there is significant variation in the reported risk, much of this variability is related to the retrospective nature of most previous studies. Undoubtedly, the quality of life of bladder and prostate cancer patients would be much improved if both normal micturition and potency are preserved, which is the subject of this article. Quality of life studies can delineate sexual function after radical prostatectomy, including the use of sexual aids. Penile erection is a neurovascular event modulated by neurotransmitters and hormonal status. The penis is innervated by autonomic and somatic nerves. Both surgery and radiation therapy appear to affect such a mechanism. Radiation is thought to produce Erectile Dysfunction (ED) by accelerating microvascular angiopathy causing cavernosal fibrosis or stenosis of the pelvic arteries and by accelerating existing arteriosclerosis, leading to vascular impotence. Years may elapse before clinically significant ED occurs. Criteria that influence recovery of erections after surgery include younger patient age, stronger erections before operation, preservation of the neurovascular bundles, and attention to fine details in the surgical technique. Recovery of erections occurs in 68% of preoperatively potent men treated with bilateral nerve-sparing surgery and in 47% of those treated with unilateral nerve-sparing surgery.  相似文献   
99.
Laparoscopy has gained widespread acceptance in common surgical practice as a diagnostic and therapeutic tool. Suspected appendicitis is still a diagnostic challenge to the general surgeon. A correct diagnosis is crucial because of the various diseases that may be responsible for the same symptoms, in order to plan the appropriate procedure or avoid an unnecessary laparotomy. Laparoscopy is the only minimally invasive technique to allow at the same time for adequate diagnosis, appropriate treatment and the best abdominal approach. Minilaparoscopy would appear to be a natural further step in the development of this technique. The aim of the present work was to illustrate retrospectively the results of an initial case-control study of minilaparoscopy vs. laparoscopy carried out at our institution. Between January and December 2002 a total of 86 patients underwent emergency and/or urgent appendectomy. Among them, 68 (79%) were operated on laparoscopically (37 [54.4%] with a minilaparoscopic approach and 31 with conventional laparoscopy), while 18 (21%) were treated by laparotomy, as performed by a well-trained surgical team. In the minilaparoscop group we registered no conversions to laparotomy and only one major postoperative complication (intra-abdominal abscess treated laparoscopically). As regards the postoperative period, generally speaking, the patients' conditions (analgesic treatment, flatus, diet, hospital discharge) were broadly the same as in the laparoscopic group. Though limited by its initial retrospective character, the present study shows that minilaparoscopic appendectomy is as safe and effective as classical laparoscopic surgery, and seems to be associated with less trauma and a more rapid postoperative recovery. Such features make minilaparoscopy a challenging alternative to conventional laparoscopy (and, of course, laparotomy) in patients referred for urgent abdominal and/or pelvic surgery.  相似文献   
100.
Background. The 3-week schedule with docetaxel (DTC) 75–100 mg/m2 is associated with severe neutropenia, gastro-intestinal side-effects and fluid retention in a significant proportion of patients, which may be of concern in more elderly or poor performance status patients. A phase I–II trial was carried out to test the feasibility and the activity of a new bimonthly schedule of DCT. Patients and methods. The trial included a phase I study which aimed at the identification of dose-limiting toxicity (DLT) and maximal tolerated dose (MTD) of DCT on a bimonthly schedule. The first group of three patients received DCT 40 mg/m2, and in absence of DLT, DCT dosage was escalated by 10 mg/m2/cycle until DLT was reached. In the phase II study, patients were randomized to receive: (a) standard 3-weekly DCT at the dose of 75 mg/m2 (calibration arm); or (b) bimonthly schedule with DCT at the dose recommended in the phase I study. All patients were pretreated with chemotherapy, mostly anthracycline-based regimens, for advanced/metastatic disease. Analysis of response rates, toxicity, and dose-intensity were the main aims of the study. Results. The DLT was represented by severe myelosuppression which was recorded in all patients treated at 70 mg/m2 dose level. Therefore, the MTD was 60 mg/m2 on a bimonthly schedule. However, the dose recommended for the phase II trial was 50 mg/m2, because no difference in delivered dose-intesity was seen between the 50 and 60 mg/m2 dose levels, and the latter dosage was still associated with grade 3 neutropenia in most patients. The parallel phase II study showed that the bimonthly schedule of DCT (50 mg/m2) allows to deliver the same dose-intensity of DCT 75 mg/m2 every 3 weeks. Grade 3–4 side-effects were rather infrequent in patients treated with the bimonthly schedule. Overall response rate (ORR) was 41 and 44% for the DCT 50 mg/m2 bimonthly and the DCT 75 mg/m2 every 3 weeks, respectively. Conclusions. Data achieved in the phase I part of the study showed that DCT 50 mg/m2 every 15 days is the recommended dose for phase II studies, while results achieved in the phase II trial suggest that DCT 50 mg/m2 in a bimonthly schedule is active as second-line chemotherapy for MBC being able to induce an ORR in the range reported for DCT 75–100 mg/m2 every 3 weeks. The bimonthly schedule is, however, associated with relatively low toxicity. This characteristic may render the bimonthly schedule particularly attractive for future phase II trials of DCT in combination with other antineoplastic agents.  相似文献   
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