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1.
Dozens of surrogates have been used to reflect the rate of aging in comparative biology. For wild organisms, the maximum reported life span is often considered a key metric. However, the connection between the maximum reported life span for a single individual and the aging rate of that species is far from clear. Our objective was to identify a pragmatic solution to calculate the aging rate from the maximum reported life span of wild birds. We explicitly linked the maximum reported life span to the aging process by employing a Weibull distribution and calculating the shape parameter in this model, which reflects the change in mortality across ages and be used as a surrogate for the aging rate. From simulated data, we demonstrated that the percentile estimator is suitable for calculating the aging rate based on the maximum reported life span. We also calculated the aging rate in 246 bird species based on published information from EURING and tested its relationship with body mass. Our study constitutes a new approach for using maximum reported life span in aging research. The aging rate calculated in the study is based on numerous assumptions/prerequisites and can be improved as more is learned about these assumptions/prerequisites.  相似文献   

2.
Qin J  Perdoni C  He B 《PloS one》2011,6(9):e23124
Inattention to current activity is ubiquitous in everyday situations. Mind wandering is an example of such a state, and its related brain areas have been examined in the literature. However, there is no clear evidence regarding neural rhythmic activities linked to mind wandering. Using a vigilance task with thought sampling and electroencephalography recording, the current study simultaneously examined neural oscillatory activities related to subjectively reported and behaviorally indexed mind wandering. By implementing time-frequency analysis, we found that subjectively reported mind wandering, relative to behaviorally indexed, showed increased gamma band activity at bilateral frontal-central areas. By means of beamformer source imaging, we found subjectively reported mind wandering within the gamma band to be characterized by increased activation in bilateral frontal cortices, supplemental motor area, paracentral cortex and right inferior temporal cortex in comparison to behaviorally indexed mind wandering. These findings dissociate subjectively reported and behaviorally indexed mind wandering and suggest that a higher degree of executive control processes are engaged in subjectively reported mind wandering.  相似文献   

3.
在前一篇文章里,作者报告了我国南部地区松树上散斑壳属(LophodermiumChev.)的8个种。本文继续报道7个种,其中广西散斑壳(L.guangxiense Y.R.Lin)是新种,东方散斑壳(L.orientale Minter)为我国新记录种,乔松散斑壳(L.pini-excelsaeAhmad)等5种为国内已知种。另外,编制了中国南部地区松树上散斑壳分种检索表。  相似文献   

4.
Survey data on people’s reported attitudes towards ethnic minorities are sometimes used as a proxy for ethnic discrimination. However, there is weak empirical evidence of a link between reported attitudes and discrimination. In this article, we use survey data on people’s attitudes towards ethnic minorities combined with a direct measure of ethnic discrimination from a field experiment in the Swedish housing market to re-examine this policy-relevant issue. We find clear evidence of a link between reported attitudes towards ethnic minorities and the extent of ethnic discrimination: in regions where attitudes are more negative, there is more discrimination, and vice versa. Thus, in contrast to most prior studies, our results suggest that reported attitudes may be a useful predictor of ethnic discrimination.  相似文献   

5.
The process of accurately gauging lifetime improvements in organic photovoltaics (OPVs) or other similar emerging technologies, such as perovskites solar cells is still a major challenge. The presented work is part of a larger effort of developing a worldwide database of lifetimes that can help establishing reference baselines of stability performance for OPVs and other emerging PV technologies, which can then be utilized for pass‐fail testing standards and predicting tools. The study constitutes scanning of literature articles related to stability data of OPVs, reported until mid‐2015 and collecting the reported data into a database. A generic lifetime marker is utilized for rating the stability of various reported devices. The collected data is combined with an earlier developed and reported database, which was based on articles reported until mid‐2013. The extended database is utilized for establishing the baselines of lifetime for OPVs tested under different conditions. The work also provides the recent progress in stability of unencapsulated OPVs with different architectures, as well as presents the updated diagram of the reported record lifetimes of OPVs. The presented work is another step forward towards the development of pass‐fail testing standards and lifetime prediction tools for emerging PV technologies.  相似文献   

6.
A case of unilateral athelia with a subcutaneous dermoid cyst in the area in question is reported. The histologic features of the cyst wall suggest that it is derived from a base in the nipple-areola complex. Dozens of cases of congenital absence of the breast have been reported, some of them associated with congenital anhidrotic ectodermal dysplasia, others with additional musculoskeletal abnormalities, and still others normal in other respects. But to our knowledge, the combination of athelia and corresponding subcutaneous dermoid cyst has not been reported.  相似文献   

7.
Proper diagnosis and treatment of traumatic brain injury (TBI) in children is becoming an increasingly problematic issue in China. This study investigated Chinese clinicians to provide information about their knowledge and experiences in diagnosis and treatment of pediatric TBI. We conducted a questionnaire survey among clinicians in the emergency departments and neurosurgery departments at 9 major hospitals in China. The questionnaire included demographic information, and knowledge and experiences regarding the diagnosis and treatment of pediatric TBI. A total of 235 clinicians completed questionnaires. 43.8% of the surveyed clinicians reported children with only scalp hematoma without any other signs and symptoms of concussion as TBI cases. Most clinicians (85.1%) reported no existing uniform diagnostic criteria for children with TBI in China. The majority of clinicians (91.9%) reported that CT scans were performed in all patients with suspected head injury as a routine procedure in their hospitals. Only 20.9% of clinicians believed that radiation from CT scanning may increase cancer risk in children. About 33.6% of the clinicians reported that they ordered CT scans to investigate suspected head injury due to the poor doctor-patient relationship in China, and to protect themselves against any medical lawsuits in the future. About 80% of the clinicians reported that there are no existing pediatric TBI treatment guidelines in China. Instead a senior doctor’s advice is the most reported guidelines regarding treating pediatric TBI (66.0%). All of the surveyed clinicians reported that the lack of diagnosis and/or treatment standard is the biggest problem in effectively diagnosing and treating pediatric TBI in China. Developing guidelines for the diagnosis and treatment of children with TBI is a high priority in China. The extremely high usage of CT for pediatric TBI in China suggests that it is important to establish evidence-based clinical decision rules to help Chinese clinicians make diagnostic and therapeutic decisions during their practice in order to identify children unlikely to have a clinically-important TBI who can be safely discharged without a CT scan.  相似文献   

8.
A persistent cloaca was found to occur in a 15-year-old female cynomolgus monkey. This is the first case reported in a nonhuman primate. The embryological basis of this anomaly is discussed, and pertinent anatomical findings in this animal are reported which demonstrate the embryologic defect.  相似文献   

9.
Breastfeeding is suggested to be a potential obesity prevention strategy, but the evidence that breast-fed infants have a lower risk of later obesity is equivocal. Fourteen studies published between 2003 and 2006 that considered the relationship between breastfeeding and risk of childhood overweight and obesity were reviewed. Three studies reported a protective effect in children (i.e., increased duration of breastfeeding was associated with a lower risk of childhood overweight/obesity), 4 reported a partial protective effect (i.e., only evident in a subgroup), 6 reported no protective effect, and 1 reported a protective effect in children but not in adults. While there is some evidence that breastfeeding may help to prevent childhood obesity, it should not be viewed as the only preventative nutrition measure. In the U.S., rates of breastfeeding have risen while rates for childhood obesity have increased dramatically. This finding reinforces the view that many factors are involved in maintaining a healthy body weight.  相似文献   

10.
The MLK1-3 activity for a series of analogues of the indolocarbazole K-252a is reported. Addition of 3,9-bis-alkylthiomethyl groups to K-252a results in potent and selective MLK inhibitors. The in vitro and in vivo survival promoting activity of bis-isopropylthiomethyl-K-252a (16, CEP-11004/KT-8138) is reported.  相似文献   

11.
Fungal chromatins are reported to exhibit unusually short nucleosomal DNA repeat lengths. To test whether this is a phylogenetic feature of fungi or rather is correlated with an apparent absence of condensed chromatin in the organisms studied, we have examined the chromatin organization and the complement of basic nuclear proteins in the fungus Entomophthora, an organism which exhibits marked chromatin condensation. Micrococcal nuclease digestion of Entomophthora chromatin revealed a nucleosomal DNA repeat length of 197 +/- 1.2 base pairs (bp). This repeat length is 20-40 bp longer than that reported for any fungus. Entomophthora nucleosomes exhibited an HI-like protein which was much less basic than the HI histones reported for higher eukaryotes but which was similar in basicity to the HI histone reported for the fungus Neurospora. However, the nucleosomal DNA repeat length of Neurospora chromatin is reported to be unusually short, whereas that of Entomophthora was found to be typical of the repeat lengths observed for chromatins of higher eukaryotes. Thus, repeat length, at least in fungi, would not appear to be directly determined by the basicity of the fungal cognate of histone HI.  相似文献   

12.
R. P. Lee  E. G. King  A. S. Russell 《CMAJ》1983,129(8):854-855
Although minor and unpleasant side effects have been reported in patients taking ibuprofen, the drug is generally regarded as a safe nonsteroidal anti-inflammatory agent. A case is reported of a previously healthy woman who experienced a severe reaction to the drug on two separate occasions.  相似文献   

13.
The genus Dysoxylum is a large genus comprising of about a dozen species, distributed in India. This is the genus which is rich in compounds like terpenoids and alkaloids. The isolated compounds from the genus were reported to have interesting biological activities. This review contains the chemical structures, along with their biological activities reported in the literature.  相似文献   

14.
少动鞘氨醇单胞菌(Sphingomonas paucimobilis) 是一种少见的条件致病菌,可引起手术后感染、创伤后腿部溃疡、菌血症、脑膜炎、慢性蜂窝织炎、手术后眼内炎等,未查见累及心瓣膜的报道.本文报道1例由少动鞘氨醇单胞菌所致感染性心内膜炎的病例.该患者为中年男性,因"反复发热2月余"入院.以发热伴左上腹痛为首...  相似文献   

15.
Lolle et al. reported a high frequency of genomic changes in ARABIDOPSIS plants carrying the hothead mutation and proposed that the changes observed were the result of a gene correction system mediated by a hypothetical RNA cache. Here, we propose a very different hypothesis to explain the data reported by Lolle et al. Our hypothesis is based on a relatively straightforward developmental aberration in which maternal cells ("Legacy cells") fuse with the developing embryo, resulting in a chimera, which could then give rise to the aberrant genetic segregations reported by Lolle et al.  相似文献   

16.
L M Cathcart  P Berger  B Knazan 《CMAJ》1979,121(2):179-184
Torture is being increasingly reported. Canada provides a refuge for some of the victims. The medical evidence may be sufficient to give an applicant refugee status. Protocols are presented for the use of physicians in examining applicants for refugee status, and a series of cases is reported in which these protocols were followed.  相似文献   

17.
Information is a concept developed inside the context of computational and computer sciences. Entropy is a concept developed inside physics context. The best concept in biology is that of "meaning" which is quite impossible to be measured as stated by some examples which are reported. A suggestion to develop a discussion in order to obtain an integration of these concepts inside the general problems of evolutionary biology is here reported to the attention of researchers.  相似文献   

18.
The lipid phase of transverse tubule membrane was probed with a variety of fatty acid spin labels. The motion of the probe increased as the distance between the spin label and polar head group increased, in agreement with results reported in other membranes. The value of the order parameter at 37 degrees C for a fatty acid spin label containing the label attached to its fifth carbon atom was closer to values reported for bacterial membranes than to the lower values reported for other mammalian membranes. Order parameters for spin labels containing the label nearer to the center of the bilayer were closer to the values reported in other mammalian membranes than to values reported for bacterial membranes. These results indicate that the lipid segments in the vicinity of the polar head group, and less so those near the center of the bilayer, are motionally more restricted in transverse tubules than in other mammalian membranes. In particular, the lipid phase of the transverse tubule membrane is less fluid than that of the sarcoplasmic reticulum membrane. A possible role of the high cholesterol content of transverse tubules in generating the lower fluidity of its lipid phase is discussed.  相似文献   

19.
Sublingual immunotherapy (SLIT) is now recognized as a viable alternative to the classical injection route and it is currently used in everyday clinical practice in Europe. Sublingual administration is particularly attractive for children since it is completely pain-free. To date, no fatalities from SLIT have been reported, but two cases of anaphylaxis to inhalant allergens have been reported. The large majority of the adverse events reported in literature is described as mild. Most of them involve the mouth (burning or itching) or the gastrointestinal tract (stomachache, nausea) and usually self-resolve in a few days without any intervention. At present, SLIT represents the main option for allergists, however, tablet immunotherapy could become an interesting alternative to sublingual drops.  相似文献   

20.
Objective To assess the association between genitourinary infections in the month before conception to the end of the first trimesterand gastroschisis.Design Case-control study with self reported infections from a computer assisted telephone interview.Setting National birth defects prevention study, a multisite, population based study including 10 surveillance systems for birth defects in the United States.Participants Mothers of 505 offspring with gastroschisis and 4924 healthy liveborn infants as controls.Main outcome measure Adjusted odds ratios for gastroschisis with 95% confidence intervals.Results About 16% (n=81) of case mothers and 9% (n=425) of control mothers reported a genitourinary infection in the relevant time period; 4% (n=21) and 2% (n=98) reported a sexually transmitted infection and 13% (n=67) and 7% (n=338) reported a urinary tract infection, respectively. Case mothers aged <25 years reported higher rates of urinary tract infection alone and in combination with a sexually transmitted infection compared with control mothers. In women who reported both types of infection, there was a greater risk of gastroschisis in offspring (adjusted odds ratio 4.0, 95% confidence interval 1.4 to 11.6).Conclusion There is a significant association between self reported urinary tract infection plus sexually transmitted infection just before conception and in early pregnancy and gastroschisis.  相似文献   

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