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Advanced age has been associated with a wide range of defects in both the innate and adaptive immune systems including diminished specific antibody responses that increase the risk of invasive pneumococcal disease (IPD) and limit the effectiveness of vaccines. However, the elderly are a heterogeneous group and measures of overall frailty may be a better indicator of disease susceptibility (or vaccine response) than chronological age alone.  相似文献   
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Damage to the genetic component of spermatozoa seems to play the main role in a majority of cases where current approaches fail to reveal the specific cause of male infertility. In this study, we compared semen quality in men assigned to two defined groups: men from couples with unexplained infertility – idiopathic infertility (A) and young men with no experiences of infertility (B). All samples were examined by standard ejaculate analysis and sperm chromatin structure assay (SCSA). Sperm chromatin damage was significantly higher in men from group A than in those from group B. Similar results were obtained by comparison of men from group A (all men were normozoospermic) with normozoospermic men from group B. According to these results, we can suppose that chromatin disorders may be the causal factor of subfertility or infertility in some of these men. No evidence for a strong association between chromatin disorders and standard parameters of ejaculates was found. We failed to confirm a relationship between smoking and sperm quality in men from any of the investigated groups. SCSA is a method that facilitates the identification of infertile men who otherwise show normal semen variables.  相似文献   
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OBJECTIVE: To compare mid-gestation sonographic measurements of all five digits of the hands of fetuses with Down syndrome with those of normal controls. METHODS: Twenty-nine fetuses between 17 and 26 weeks' gestation which had been confirmed by karyotyping to have Down syndrome were included in this prospective study. Each fetus was scanned once and the digits of only one hand were measured. Measurements were compared with those of 302 previously reported normal controls matched for gestational age. All measurements were expressed in multiples of the gestation-specific normal median (MoM) for each digit. RESULTS: Compared to 1 MoM for the length of Digits 1 to 5 from the normal population, the respective values in the Down syndrome digits were: 0.94, 0.85, 0.92, 0.88 and 0.85 MoM, representing values significantly lower than normal (P < 0.05; t-test). CONCLUSIONS: All five digits of the hands of fetuses with Down syndrome are shorter than are those of euploid fetuses. Integration of fetal digit measurement into the antenatal assessment of selected high-risk cases may be of value although confirmation of our findings should be obtained before this measurement is incorporated into Down syndrome screening in the general population.  相似文献   
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Background: Dreaming reported after anesthesia remains a poorly understood phenomenon. Dreaming may be related to light anesthesia and represent near-miss awareness. However, few studies have assessed the relation between dreaming and depth of anesthesia, and their results were inconclusive. Therefore, the authors tested the hypothesis that dreaming during anesthesia is associated with light anesthesia, as evidenced by higher Bispectral Index values during maintenance of anesthesia.

Methods: With approval, 300 consenting healthy patients, aged 18-50 yr, presenting for elective surgery requiring relaxant general anesthesia with a broad range of agents were studied. Patients were interviewed on emergence and 2-4 h postoperatively. The Bispectral Index was recorded from induction until the first interview. Dream content and form were also assessed.

Results: Dreaming was reported by 22% of patients on emergence. There was no difference between dreamers and nondreamers in median Bispectral Index values during maintenance (37 [23-55] vs. 38 [20-59]; P = 0.68) or the time at Bispectral Index values greater than 60 (0 [0-7] vs. 0 [0-31] min; P = 0.38). Dreamers tended to be younger and male, to have high home dream recall, to receive propofol maintenance or regional anesthesia, and to open their eyes sooner after surgery. Most dreams were similar to dreams of sleep and were pleasant, and the content was unrelated to surgery.  相似文献   

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