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1.
Erin Henry Luca Santini Mark A. J. Huijbregts Ana Benítez-López 《Global Ecology and Biogeography》2023,32(2):267-280
Aim
Whether intraspecific spatial patterns in body size are generalizable across species remains contentious, as well as the mechanisms underlying these patterns. Here we test several hypotheses explaining within-species body size variation in terrestrial vertebrates including the heat balance, seasonality, resource availability and water conservation hypotheses for ectotherms, and the heat conservation, heat dissipation, starvation resistance and resource availability hypotheses for endotherms.Location
Global.Time period
1970–2016.Major taxa studied
Amphibians, reptiles, birds and mammals.Methods
We collected 235,905 body size records for 2,229 species (amphibians = 36; reptiles = 81; birds = 1,545; mammals = 567) and performed a phylogenetic meta-analysis of intraspecific correlations between body size and environmental variables. We further tested whether correlations differ between migratory and non-migratory bird and mammal species, and between thermoregulating and thermoconforming ectotherms.Results
For bird species, smaller intraspecific body size was associated with higher mean and maximum temperatures and lower resource seasonality. Size–environment relationships followed a similar pattern in resident and migratory birds, but the effect of resource availability on body size was slightly positive only for non-migratory birds. For mammals, we found that intraspecific body size was smaller with lower resource availability and seasonality, with this pattern being more evident in sedentary than migratory species. No clear size–environment relationships were found for reptiles and amphibians.Main conclusions
Within-species body size variation across endotherms is explained by disparate underlying mechanisms for birds and mammals. Heat conservation (Bergmann's rule) and heat dissipation are the dominant processes explaining biogeographic intraspecific body size variation in birds, whereas in mammals, body size clines are mostly explained by the starvation resistance and resource availability hypotheses. Our findings contribute to a better understanding of the mechanisms behind species adaptations to the environment across their geographic distributions. 相似文献2.
Effect of menstrual cycle phase and hormonal treatments on evaluation of tubal patency in baboons 下载免费PDF全文
Jeffrey T. Jensen Carol Hanna Emily Mishler Jeong Y. Lim Ov D. Slayden 《Journal of medical primatology》2018,47(1):40-45
Background
We evaluated whether menstrual cycle phase influences the assessment of tubal patency by hysterosalpingography (HSG) in baboons.Methods
Retrospective analysis of baseline tubal patency studies and serum estradiol (E2) and progesterone (P4) values obtained from female baboons used as models for development of non‐surgical permanent contraception in women. The main outcome measure was bilateral tubal patency (BTP) in relationship with estradiol level.Results
Female baboons (n = 110) underwent a single (n = 81), two (n = 26), or three (n = 3) HSG examinations. In 33/142 (23%) HSG examinations, one or both tubes showed functional occlusion (FO). The median E2 in studies with BTP (49 pg/mL) was significantly higher than in those studies with FO (32 pg/mL, P = .005). Among 18 animals with repeat examinations where serum E2 changed from <60 to ≥ 60 pg/mL, 13 results changed from FO to BTP (P = .0001). No sets showed a change from BTP to FO with an increase in estradiol.Conclusion
In baboons, functional occlusion of the fallopian tube is associated with low estradiol levels, supporting a role for estrogen‐mediated relaxation of the utero‐tubal junction. 相似文献3.
Cortical beta EEG oscillations related to changes in muscle tone activity during sleep in spider monkey (Ateles geoffroyi) 下载免费PDF全文
Manuel Alejandro Cruz‐Aguilar Miguel Angel Guevara Marisela Hernández‐González Ignacio Ramírez‐Salado Enrique Hernández‐Arteaga Fructuoso Ayala‐Guerrero 《Journal of medical primatology》2018,47(1):67-74
Background
The physiological mechanisms that allow for sleeping in a vertical position, which is primordial for arboreal primates, have not been studied yet.Methods
A non‐invasive polysomnographic study of 6 spider monkeys (Ateles geoffroyi) was conducted. The relative beta power of the motor cortex and its linear relation with muscle tone in the facial mentalis muscle and the abductor caudae medialis muscle of the tail during wakefulness and sleep stages were calculated.Results
A strong negative linear relationship (r = ?.8, P = .03) was found between the relative power of the beta2 band in the left motor cortex and abductor caudae medialis muscle tone during delta sleep.Conclusions
The left motor cortex, through beta2 band activity, interacts with abductor caudae medialis muscle tonicity during delta sleep. This interaction takes part in the mechanisms that regulate the sleep postures. 相似文献4.
5.
Telomere length determined by the fluorescence in situ hybridisation distinguishes malignant and benign cells in cytological specimens 下载免费PDF全文
Y. Matsuda A. Suzuki S. Esaka Y. Hamashima M. Imaizumi M. Kinoshita H. Shirahata Y. Kiso H. Kojima M. Matsukawa Y. Fujii N. Ishikawa J. Aida K. Takubo T. Ishiwata M. Nishimura T. Arai 《Cytopathology》2018,29(3):262-266
Background
Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.Methods
Aspiration samples (n = 41) were smeared on glass slides and used for FISH.Results
Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound‐guided FNA samples from the pancreas (n = 18).Conclusions
The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients. 相似文献6.
Seroprevalence of Helicobacter pylori in Korea: A multicenter,nationwide study conducted in 2015 and 2016 下载免费PDF全文
Jeong Hoon Lee Kee Don Choi Hwoon‐Yong Jung Gwang Ho Baik Jong Kyu Park Sung Soo Kim Byung‐Wook Kim Su Jin Hong Hyun Lim Cheol Min Shin Si Hyung Lee Seong Woo Jeon Ji Hyun Kim Cheol Woong Choi Hye‐Kyung Jung Jie‐Hyun Kim Suck Chei Choi Jin Woong Cho Wan Sik Lee Soo‐Young Na Jae Kyu Sung Kyung Ho Song Jun‐Won Chung Sung‐Cheol Yun Korean College of Helicobacter Upper Gastrointestinal Research 《Helicobacter》2018,23(2)
Background
The Korean College of Helicobacter and Upper Gastrointestinal Research has studied Helicobacter pylori (H. pylori) prevalence since 1998 and found a dynamic change in its prevalence in Korea. The aim of this study was to determine the recent H. pylori prevalence rate and compare it with that of previous studies according to socioeconomic variables.Methods
We planned to enroll 4920 asymptomatic Korean adults from 21 centers according to the population distribution of seven geographic areas (Seoul, Gyeonggi, Gangwon, Chungcheong, Kyungsang, Cholla, and Jeju). We centrally collected serum and tested H. pylori serum IgG using a chemiluminescent enzyme immunoassay.Results
We analyzed 4917 samples (4917/4920 = 99.9%) from January 2015 to December 2016. After excluding equivocal serologic results, the H. pylori seropositivity rate was 51.0% (2414/4734). We verified a decrease in H. pylori seroprevalence compared with previous studies performed in 1998, 2005, and 2011 (P < .0001). The H. pylori seroprevalence rate differed by area: Cholla (59.5%), Chungcheong (59.2%), Kyungsang (55.1%), Jeju (54.4%), Gangwon (49.1%), Seoul (47.4%), and Gyeonggi (44.6%). The rate was higher in those older than 40 years (38.1% in those aged 30‐39 years and 57.7% in those aged 40‐49 years) and was lower in city residents than in noncity residents at all ages.Conclusions
Helicobacter pylori seroprevalence in Korea is decreasing and may vary according to population characteristics. This trend should be considered to inform H. pylori‐related policies. 相似文献7.
Objective
We investigated the relationship between saliva and dental biofilm characteristics, oral hygiene behaviours and the number of remaining teeth in a sample of older Koreans.Materials and methods
This cross‐sectional study included 133 participants, aged 65 years and older, recruited from senior welfare facilities in Incheon, South Korea. The outcome variable was the number of remaining teeth, and its associations with the independent variables of participants’ general characteristics, salivary haemoglobin level, dental biofilm acidogenicity, salivary flow rate and oral hygiene behaviours were assessed. For statistical analyses, chi‐squared test and step‐wise multiple linear regression were used.Results
The multiple linear regression model, which included all related factors identified in the bivariate analyses, showed that older adults who had high salivary haemoglobin levels (P < .05), brushed their teeth using the horizontal scrub method (P< .001), and did not use an interproximal cleaning device (P < .01) were more likely to have fewer remaining teeth. However, dental biofilm acidogenicity was not associated with the number of remaining teeth.Conclusion
The number of remaining teeth was associated with salivary haemoglobin level, appropriate toothbrushing technique and interdental cleaning. These findings suggest that the monitoring of salivary haemoglobin may contribute to the prevention of tooth loss caused by periodontal disease. 相似文献8.
Ana M Enciu Mihnea I Nicolescu Catalin G Manole Dafin F Mure?anu Lauren?iu M Popescu Bogdan O Popescu 《BMC neurology》2011,11(1):75
Background
Neuroregeneration is a relatively recent concept that includes neurogenesis, neuroplasticity, and neurorestoration - implantation of viable cells as a therapeutical approach. 相似文献9.
Antibiotics resistance of Helicobacter pylori in children with upper gastrointestinal symptoms in Hangzhou,China 下载免费PDF全文
Background
The decreasing eradication rate of Helicobacter pylori is mainly because of the progressive increase in its resistance to antibiotics. Studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to investigate the resistance rates and patterns of H. pylori strains isolated from children.Materials and Methods
Gastric mucosa biopsy samples obtained from children who had undergone upper gastrointestinal endoscopy were cultured for H. pylori, and susceptibility to six antibiotics (clarithromycin, amoxicillin, gentamicin, furazolidone, metronidazole, and levofloxacin) was tested from 2012‐2014.Results
A total of 545 H. pylori strains were isolated from 1390 children recruited. The total resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin were 20.6%, 68.8%, and 9.0%, respectively. No resistance to amoxicillin, gentamicin, and furazolidone was detected. 56.1% strains were single resistance, 19.6% were resistant to more than one antibiotic, 16.7% for double resistance, and 2.9% for triple resistance in 413 strains against any antibiotic. And the H. pylori resistance rate increased significantly from 2012‐2014. There was no significant difference in the resistance rates to clarithromycin, metronidazole, and levofloxacin between different gender, age groups, and patients with peptic ulcer diseases or nonulcer diseases.Conclusions
Antibiotic resistance was indicated in H. pylori strains isolated from children in Hangzhou, and it increased significantly during the 3 years. Our data strongly support current guidelines, which recommend antibiotic susceptibility tests prior to eradication therapy. 相似文献10.
Brief report: Lactobacillus bulgaricus GLB44 (Proviotic™) plus esomeprazole for Helicobacter pylori eradication: A pilot study 下载免费PDF全文
Background
Recent studies of Lactobacillus delbrueckii subsp. bulgaricus GLB44 plus a proton‐pump inhibitor (PPI) reported cures of more than 90% of patients with active Helicobacter pylori infections.Aim
To confirm the high H. pylori cure rates reported previously.Method
A pilot study was done in healthy H. pylori‐infected volunteers using 3‐gram sachet (3 billion cells) of L. delbrueckii GLB44 plus 22.3 mg of esomeprazole b.i.d., for 14 days. The result was determined by urea breath testing 4 weeks after therapy. Stopping rules required for ending enrollment if less than 3 of the first 10 subjects were cured.Results
Nine subjects were entered and because all failed to achieve negative urea breath test, the stopping rule required the study to end.Conclusion
We were unable to confirm reports of achieving a high H. pylori cure rate with L. delbrueckii GLB44 plus a PPI. 相似文献11.
Anna B Roehl Marc Hein Philipp D Loetscher Jan Rossaint Joachim Weis Rolf Rossaint Mark Coburn 《BMC neurology》2010,10(1):97
Background
We investigated the neuroprotective properties of levosimendan, a novel inodilator, in an in vitro model of traumatic brain injury. 相似文献12.
Chia-Huei Lee Chih-Min Liu Chun-Chiang Wen Shun-Min Chang Hai-Gwo Hwu 《Journal of biomedical science》2010,17(1):2
Background
Schizophrenia is a complex disorder with involvement of multiple genes. 相似文献13.
Background
Current data on the pattern of parkinsonism and Parkinson's disease in Nigerians are sparse. 相似文献14.
Karina Reiter Christoph Plutzar Dietmar Moser Philipp Semenchuk Karl-Heinz Erb Franz Essl Andreas Gattringer Helmut Haberl Fridolin Krausmann Bernd Lenzner Johannes Wessely Sarah Matej Robin Pouteau Stefan Dullinger 《Global Ecology and Biogeography》2023,32(6):855-866
Aim
Land use is the most pervasive driver of biodiversity loss. Predicting its impact on species richness (SR) is often based on indicators of habitat loss. However, the degradation of habitats, especially through land-use intensification, also affects species. Here, we evaluate whether an integrative metric of land-use intensity, the human appropriation of net primary production, is correlated with the decline of SR in used landscapes across the globe.Location
Global.Time period
Present.Major taxa studied
Birds, mammals and amphibians.Methods
Based on species range maps (spatial resolution: 20 km × 20 km) and an area-of-habitat approach, we calibrated a “species–energy model” by correlating the SR of three groups of vertebrates with net primary production and biogeographical covariables in “wilderness” areas (i.e., those where available energy is assumed to be still at pristine levels). We used this model to project the difference between pristine SR and the SR corresponding to the energy remaining in used landscapes (i.e., SR loss expected owing to human energy extraction outside wilderness areas). We validated the projected species loss by comparison with the realized and impending loss reconstructed from habitat conversion and documented by national Red Lists.Results
Species–energy models largely explained landscape-scale variation of mapped SR in wilderness areas (adjusted R2-values: 0.79–0.93). Model-based projections of SR loss were lower, on average, than reconstructed and documented ones, but the spatial patterns were correlated significantly, with stronger correlation in mammals (Pearson's r = 0.68) than in amphibians (r = 0.60) and birds (r = 0.57).Main conclusions
Our results suggest that the human appropriation of net primary production is a useful indicator of heterotrophic species loss in used landscapes, hence we recommend its inclusion in models based on species–area relationships to improve predictions of land-use-driven biodiversity loss. 相似文献15.
Background
The disabled population constitutes a class of people needing special care and necessitating important economic and social effort. 相似文献16.
Past vegetation dynamics in the Yellowstone region highlight the vulnerability of mountain systems to climate change 下载免费PDF全文
Virginia Iglesias Cathy Whitlock Teresa R. Krause Richard G. Baker 《Journal of Biogeography》2018,45(8):1768-1780
Aim
Reconstruct the long‐term ecosystem dynamics of the region across an elevational gradient as they relate to climate and local controls. In particular, we (1) describe the dominant conifers' history; (2) assess changes in vegetation composition and distribution; and (3) note periods of abrupt change versus stability as means of better understanding vegetation responses to environmental variability.Location
Greater Yellowstone Ecosystem (GYE; USA).Time period
16.5 ka bp ‐present.Major taxa studied
Juniperus, Picea, Abies, Pinus, Pseudotsuga.Methods
The vegetation reconstruction was developed from 15 pollen records. Results were interpreted based on modern pollen–vegetation relationships estimated from a suite of regression‐based approaches.Results
Calibrated pollen data suggest that late‐glacial vegetation, dominated by shrubs and Juniperus, lacks a modern counterpart in the area. Picea, Abies and Pinus expanded at 16 ka bp in association with postglacial warming and co‐occurred in mixed‐conifer parkland/forest after 12 ka bp . This association along with Pinus contorta forest, which was present after 9 ka bp , has persisted with little change at middle and high elevations to the present day. This stability contrasts with the dynamic history of plant communities at low elevations, where shifts between parkland, steppe and forest over the last 8,000 years were likely driven by variations in effective moisture and fire.Main conclusions
The postglacial vegetation history of the GYE highlights the dynamic nature of mountain ecosystems and informs on their vulnerability to future climate change: (1) most of the conifers have been present in the area for >12,000 years and survived climate change by adjusting their elevational ranges; (2) some plant associations have exhibited stability over millennia as a result of nonclimatic controls; and (3) present‐day forest cover is elevationally more compressed than at any time in history, probably due to the legacy of the Medieval Climate Anomaly and the Little Ice Age. 相似文献17.
Background
In this paper a novel method for prostate segmentation in transrectal ultrasound images is presented. 相似文献18.
Ramanathan K Kasimanickam Vanmathy R Kasimanickam Jacobo S Rodriguez Kevin D Pelzer Philip D Sponenberg Craig D Thatcher 《Reproductive biology and endocrinology : RB&E》2010,8(1):86
Background
Tocopherols have biphasic, proangiogenic and antiangiogenic therapeutic effects. The objective of this clinical trial was to clarify tocopherol's placental angiogenic potential in late pregnant ewes following oral supplementation. 相似文献19.
I. Natividad‐Bonifacio F.J. Fernández E.I. Quiñones‐Ramírez E. Curiel‐Quesada C. Vázquez‐Salinas 《Journal of applied microbiology》2013,114(5):1539-1546
Aims
This work aims to demonstrate the presence of several genes and factors associated with virulence in strains isolated from the environment at Pueblo Viejo Lagoon, State of Veracruz, Mexico.Methods and Results
In this study, we investigated the production of V. vulnificus virulence factors, as cytolysin (haemolysin), RTX toxin, metalloprotease, siderophores, capsular polysaccharide, adhesion structures (like type IV pili), and polar and lateral flagella, involved in swimming and swarming (or, at least, the presence of genes encoding some of them) in 40 strains of V. vulnificus isolated from water and food. The results indicate that strains of environmental origin possess potential virulence characteristics.Conclusions
Caution should be exercised when consuming raw shellfish (especially by those more susceptible risk groups).Significance and Impact of the Study
This is the first work focused on the evaluation of V. vulnificus virulence factors in Mexico. 相似文献20.
Michal Amir Shabtai Romano Shlomit Goldman Eliezer Shalev 《Reproductive biology and endocrinology : RB&E》2009,7(1):152-8