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1.
The impact of a social stress in gestation and an enriched pen in lactation on components of sow maternal behavior was studied in a 2 × 2 factorial experiment. At breeding, 41 sows were assigned to a social mixing stress treatment (T) during mid-gestation or a control group (C). During lactation, half of the T and C sows were housed in straw enriched pens (E) (1.57 m × 4.10 m) and the others in standard farrowing crates (S) (0.68 m × 2.10 m). The mixing stress consisted in introducing each T sow to the home pen of two unfamiliar sows twice for 1 week, from d 39 to 45 and 59 to 65 of gestation. Aggressive behavior was observed and lesion scores were taken to confirm that a social stress occurred. During lactation, the responses of sows to a simulated piglet crush test on d 3 and an isolated piglet playback test on d 21 were observed. Postural budgets of sows were automatically detected using accelerometers on d 5 and 19 of lactation. Sow-initiated social contacts with the piglets were observed continuously from video recordings on d 6 and 20 of lactation. Data were analyzed with a mixed models procedure. The social stress treatment had an impact on the response of sows to isolated piglet vocalizations with T sows showing longer latencies to respond vocally than C sows (P = 0.035). In early lactation, T sows spent more time lying ventrally than C sows (P = 0.007). Furthermore, the social stress had an impact on the space use in the enriched housing, with T sows spending less time in the nesting straw area of the pen than C sows (P = 0.018). Housing also impacted maternal behavior with E sows tending to spend more time lying ventrally than S sows in late lactation (P = 0.067) and tending to have more social contacts with their piglets than S sows in early lactation (P = 0.058). In conclusion, the social stress during gestation had a slight negative impact on sow maternal behavior, and while an enriched farrowing pen allowed for more opportunities to express maternal behavior, it did not counteract the negative effects of gestation stress.  相似文献   

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3.
《Cancer epidemiology》2014,38(5):471-478
PurposeThe expression of methylenetetrahydrofolate reductase (MTHFR) is associated with acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). Most studies have linked the common functional C677T and A1298C polymorphisms of the MTHFR gene and susceptibility to AML and CML, but the results were not consistent. The aim of the present study was to derive a more precise estimation of the relationship.MethodsMeta-analyses assessing the association of MTHFR C677T and A1298C variations with AML and CML were conducted. Eligible articles were identified from the PubMed and EMBASE databases. All statistical analyses were conducted using Review Manager Software.Results10 and 10 studies were included in the meta-analysis about the role of C677T polymorphism on the AML and CML risks, respectively; 6 and 4 studies were included about the role of A1298C polymorphism on the AML and CML risks, respectively. Overall, both the C677T and A1298C polymorphisms were significantly associated with CML risk under the recessive model (P = 0.04, OR = 1.35, 95% CI = 1.02–1.79 for C677T and P = 0.003, OR = 2.17, 95% CI = 1.29–3.63 for A1298C). In addition, the risk of CML was higher in 1298CC genotype carriers than in 1298AA genotype carriers (P = 0.004, OR = 2.17, 95% = 1.28–3.69). Conversely, the overall data failed to indicate a significant association of C677T or A1298C polymorphisms with AML risk under any model.ConclusionsThe findings provide evidence that C677T and A1298C polymorphisms are risk factors for CML risk.  相似文献   

4.
《IRBM》2014,35(3):158-163
The main objective of this paper was to assess the performance of the ambulatory device μHematron to measure indirectly skin blood flow relative to the well-established Laser Doppler flowmetry method. The μHematron device is dedicated to the non-invasive measurement of effective thermal conductivity of living tissues, based on the thermal clearance method. Its major advantage is its ambulatory functionality, as available methods for evaluation of microcirculatory activity are non-ambulatory methods. An experiment was conducted on ten healthy women exposed for one hour in three different thermal environments (22 °C, 25 °C and 30 °C). Skin microcirculatory activity was analyzed after an acclimatization period of 30 minutes. The time between each exposure was at least one hour. Performances of the μHematron device were assessed and a comparative study with a laser Doppler perfusion monitor (LDPM) was performed. Good correlation coefficients between the two devices (r = 0.71 at T1 = 22 °C, r = 0.77 at T2 = 25 °C and r = 0.83 at T3 = 30 °C) were obtained while the LDPM signal was filtered by a low pass filter (0.1 Hz). These results showed that continuous monitoring of effective thermal conductivity was possible in neutral and warm ambiences. Then, the μHematron device could be considered as a complementary tool to Doppler techniques for the investigation of skin blood flow, when ambulatory conditions are required.  相似文献   

5.
Background: Genetic predispositions to disease have focused on highly penetrant causative changes in tumor suppressor genes or genes associated with DNA mismatch repair. New investigations are revealing new genetic associations with disease that are more subtle in their association with disease and require characterization. Methods: In this report we have examined the tumor characteristics in a group of patients who have been shown to harbor two polymorphisms in two genes that are associated with the immune system NOD2 and TNFα. Results: Colorectal cancers from patients with NOD2 3020insC and TNFα-1031T/T constitutional changes are mostly right-sided disease (OR = 2.21, p = 0.03) with a tendency to higher stages (OR = 2.41, p = 0.06), increased number of associated polyps (OR = 1.77, p = 0.16) and later age of average age of disease onset (p = 0.039). Conclusion: The results reveal that there appear to be specific characteristics associated with the tumors that may aid in determining management strategies to reduce the risk of disease.  相似文献   

6.
Toll-like receptors (TLRs) have emerged as crucial sensors of invading microbes through recognition of pathogen-associated molecular patterns (PAMPs) in viruses, bacteria, fungi and protozoa. The polymorphisms in TLRs are closely associated with the resistance to pathogen infections. TLR3 involved in the recognition of double stranded RNA in humans, mice, pigs and fishes. In present study, the nucleotide sequence polymorphisms of TLR3 gene in grass carp (Ctenopharyngodon idella) (CiTLR3) were investigated to explore their association with susceptibility/resistance to grass carp reovirus (GCRV). Twelve single nucleotide polymorphisms (SNPs) and an ins/del mutation were detected in the complete sequence of CiTLR3. Ten of them were sited in the non-coding region. The two SNPs in exon were synonymous mutation. The ins/del mutation was coincidental at the start codon. To investigate the association between the polymorphism and the susceptibility/resistance to GCRV, we selected eight SNPs in the non-coding region and analyzed the genotype and allele distribution in susceptible and resistant groups with PCR-RFLP. The statistical results indicated that only ?764 G/T was significantly associated with the resistance of grass carp to GCRV both in genotype (P = 0.040) and allele (P = 0.025). Linkage disequilibrium analysis revealed ?543 A/G, ?488 G/T, 4116 G/T and 4731 C/T were linkage disequilibrium, and haplotype analysis revealed that haplotype GTTT frequency in susceptible group was significantly higher than that in the resistant group (OR = 2.01, 95% CI 0.996–4.043, P = 0.049). To further confirm the correlation, an additional infection experiment was carried out. The mortality in the ?764 GG genotype individuals was significantly lower than GT genotype (OR = 0.208, 95% CI 0.067–0.643, P = 0.011) and TT genotype (OR = 0.183, 95% CI 0.052–0.648, P = 0.015). All the results indicated that haplotype GTTT and genotype ?764 TT and ?764 GT individuals were susceptible to GCRV while ?764 GG was resistant, which could be the optional markers for selective breeding for the GCRV-resistant grass carp in future.  相似文献   

7.
《Cytokine》2014,65(2):210-216
Amongst host genetic factors, cytokine gene polymorphism can be anticipated to be an important factor as qualitative, quantitative and time of secretion play an important role in disease outcome. We have investigated association of cytokine promoter SNPs with risk of Plasmodium falciparum malaria and disease severity in a case control study in malaria endemic Karbi Anglong district of Assam, India.Frequency of IL-8-251T/A (p = 0.03 and p = 0.01) and TGF-β1-509C/T (p = 0.02 and p = 0.03) was higher in malaria in comparison to control participants and non-malarial fever controls. Interestingly, a higher frequency of mutant allele of IL-10-819T/C was observed in non-malarial fever controls compared to malaria thus suggesting its role as a distinguishing marker of the two disease groups. Higher IL-8 expression and increased frequency of IL-8-251T/A in complicated malaria (p = 0.002) was reported indicating its role in susceptibility to complicated malaria.In conclusion, our study suggests the role of mutant genotype of IL-8-251T/A as a marker of complicated malaria in our population. Surprisingly, decreased expression of TGF-β1 in uncomplicated malaria even in presence of high expressing mutant genotype was observed and needs to be investigated in context of the pool of activated cells producing the cytokine.  相似文献   

8.
Rheumatoid arthritis (RA) is a chronic disease. It causes chronic inflammation of the joint. Recent studies suggested that interleukin 4 (IL4) contributes to susceptibility and severity of rheumatoid arthritis (RA). Especially, it was reported that promoter polymorphism (−590, T/C) of IL4 gene has been associated with susceptibility of RA. The aim of present study was to investigate whether the promoter polymorphism (−590, T/C) of IL4 gene is associated with the susceptibility of RA using meta-analysis. And in order to perform meta-analysis, comprehensive meta analysis program was used. Genetic models (co-dominant, dominant, recessive, and allele) were used to determine odds ratios (ORs), 95% confidence intervals (CIs), and P values. Nine case-control studies with case and control design were included in this meta-analysis. Overall, meta-analysis revealed a strong association with susceptibility of RA [OR = 1.303, 95% CI = 1.093–1.554, P = 0.003 in allele model (C vs. T); OR = 1.247, 95% CI = 1.054–1.474, P = 0.010 in dominant model (CC vs. CT + TT); OR = 2.148, 95% CI = 1.263–3.651, P = 0.005 in recessive model (CC + CT vs. TT)]. Our data demonstrated that promoter polymorphism (−590, T/C) of IL4 gene may be contributed to susceptibility of RA. However, more studies with a larger sample size are needed to provide more precise evidence.  相似文献   

9.
Checkpoint kinase 2 gene (CHEK2) alterations increase risk of several cancer types. We analyzed selected CHEK2 alterations in 270 Czech pancreatic cancer patients and in 683 healthy controls. The pancreatic cancer risk was higher in individuals who inherited rare alterations in CHEK2 region involving forkhead-associated domain other than I157T (OR = 5.14; 95% CI = 0.94–28.23) but the observed association was non-significant (p = 0.057). The most frequent I157T mutation did not alter the pancreatic cancer risk and neither the followed deletion of 5395 bp nor c.1100delC were found in any of pancreatic cases. We conclude that the I157T, other alterations in its proximity, del5395 and c.1100delC in CHEK2 do not predispose to pancreatic cancer risk in the Czech population.  相似文献   

10.
We explored the relationships between surface-soil (1–20 cm) organic carbon isotopic signatures and associated climatic factors in central-east Asia in an attempt to develop transfer functions that can be used to retrieve the paleoclimatic information stored in the thick eolian–paleosol sequences within the area. Our analysis shows that the negative correlation between the surface-soil organic δ13C values and the mean annual precipitation is robust (R2 = 0.453; n = 196; p < 0.05) and the negative correlation with the growing-season (April–September) precipitation is more significant (R2 = 0.4966; n = 196; p < 0.05). Our study further shows that the positive correlation between the surface-soil organic δ13C values and mean growing-season aridity is most significant (R2 = 0.5805; n = 196; p < 0.05). We have smoothed both the organic δ13C values and the mean growing-season aridity values using a 3-point moving-window average-filter method in an attempt to remove some of random errors and found that the positive correlation between the two is further increased (R2 =  0.7784; n =  192; p < 0.05). These robust linear relationships demonstrate their value in reconstructing paleoclimate changes in the study area. The documented climatic dependency of the surface-soil carbon isotopic composition in the study area might have resulted both from the humidity-related isotopic enrichment processes of the dominant C3 plants (stomatal conductance and photosynthetic discrimination) and from the aridity-related abundance of C4 plants (mainly Chenopodiaceae species) along the S–N bioclimatic gradient.  相似文献   

11.
The constraints of captivity may often require non-human primates to experience restrictions in space for both long- and short-term periods of time. The tension-reduction model predicts that great apes should increase affiliative behaviors and decrease aggressive behaviors as a coping strategy. The conflict avoidance model, however, predicts that great apes should decrease all social interactions (affiliative and aggressive) as a coping strategy. The purpose of this study was to test the conflict-avoidance and tension-reduction models by examining the effects of both short-term (1–2 days) and long-term (6 months) changes in spatial density on social behavior in 23 adult captive chimpanzees (6 males, 17 females) housed at the Primate Foundation of Arizona. Affiliative (i.e., social groom, social play) and agonistic (i.e., charging display, attack) were assessed using scan-sampling techniques while subjects were rotated from high-density to low-density conditions for varying lengths of time. Results of short-term increases in spatial density (crowding) supported the conflict-avoidance strategy for females, through reduced levels of aggressive (F1,16 = 17.11, p = 0.001) and affiliative (F1,16 = 21.13, p < 0.001) behaviors. Males, however, supported the tension-reduction model during short-term high-density by decreasing aggression (F1,5 = 10.53, p = 0.02) while increasing affiliation (F1,5 = 9.10, p = 0.03). Females partially supported the tension-reduction model during long-term high-density by increasing affiliative behaviors (F1,16 = 14.19, p = 0.002) compared to short-term high-density levels, while rates of aggression remained low. Finally, males supported the tension-reduction by reducing aggression (F1,5 = 7.668, p = 0.04) and increasing affiliation (F1,5 = 6.08, p = 0.05) during long-term high-density. Results confirm that chimpanzees use different strategies during short-term versus long-term increases in spatial density and that these strategies may be influenced by individual sex. However, sample sizes are small and additional research on male chimpanzees is needed.  相似文献   

12.
PurposeThe aim of this study was to investigate the influence of the TNF -308 G/A polymorphism in the promoter region of the tumor necrosis factor-α gene on the susceptibility and severity of rheumatoid arthritis (RA) in individuals from the Brazilian Amazon.MethodsA total of 323 individuals—192 healthy controls without arthritis and 131 individuals suffering from arthritis—were genotyped for this polymorphism using a methodology based on PCR-RFLP.ResultsThe frequency of the A allele (TNF2) in rheumatoid arthritis sufferers was not significantly higher than in the controls (p = 0.926; OR = 0.97; confidence interval 0.54–1.76). However, using a logistic regression model, when the patients were stratified according to whether the manifestations were preponderantly articular or systemic, there was a strong association between the TNF2 allele and systemic arthritis (p = 0.001; OR = 5.89; confidence interval = 1.98–17.5) as well as the use of anti-TNF immunotherapy (p = 0.023; OR = 1.10; confidence interval = 1.00–1.14). The main factors that were found to influence the risk of extra-articular disease were age greater than or equal to 60 years (p = 0.008; OR = 4.06; confidence interval = 1.45–11.38), disease duration greater than 10 years (p = 0.031; OR = 3.10; confidence interval = 1.11–8.63) and positive rheumatoid factor (p = 0.035; OR = 2.07; confidence interval = 1.05–4.09).ConclusionsThese results suggest that the TNF2 allele is associated with the more serious forms of the disease in individuals from the Brazilian Amazon but not with a risk for developing RA.  相似文献   

13.
《Cytokine》2015,74(2):253-257
Interleukin-10 (IL-10) is a cytokine that plays an important role in the regulation of the immune system. Gene polymorphisms of IL-10 have been associated with the different expression levels of this cytokine. In hepatitis C virus infection, IL-10 appears to interfere with the progression of disease, viral persistence and the response to therapy. This study investigated genetic variability in the IL-10 gene promoter between patients infected with hepatitis C virus (HCV) and healthy individuals, associating the frequency of polymorphisms with different aspects of viral infection. This is a case-control study with 260 patients who were infected with HCV and 260 healthy individuals. Genotyping of the polymorphisms was performed using the technique of amplification refractory mutation system PCR (ARMS-PCR) for regions of the IL-10 gene promoter (-1082 G/A, -819 C/T, -592 C/A). The frequencies of alleles and genotypes related to polymorphisms in the IL-10 gene promoter showed a higher frequency of the G allele and genotype GG in the -1082 region between the infected group and the control group (p = 0.005 and p = 0.001, respectively), whereas the AA genotype was significantly more frequent in the control group. The frequencies of the haplotypes GTA and GCC were higher in the group of infected individuals, whereas the haplotype ATA was more frequent in the healthy group (p < 0.006). It was also observed that the genotypes GG and AG in the region -1082 were significantly more frequent among patients infected with HCV who were in advanced stages of fibrosis and cirrhosis (p = 0.042). No association was observed between polymorphisms of IL-10 and sustained virologic response (SVR).  相似文献   

14.
We recently reported an association between interleukin-6 (IL6) polymorphisms (SNPs) and haplotypes and aggressive periodontitis (AgP). The aim of this study was to investigate this association in a larger cohort of subjects, affected by either aggressive or chronic periodontitis. Five IL6 SNPs were analyzed in 765 subjects (167 generalized aggressive periodontitis, 57 localized aggressive, 310 chronic periodontitis and 231 periodontally healthy). Among Caucasians (n = 454) there were moderate associations for ?1363T allele (p = 0.011) and for ?174GG and ?1363GG genotypes with diagnosis of periodontitis (respectively, p = 0.044, OR = 1.6, 95% CI = 1.0–2.4, and p = 0.017, OR = 1.8, 95% CI = 1.1–2.8, adjusted for age, gender and smoking). Haplotypes containing the ?174G>C, ?1363G>T and ?1480C>G polymorphisms were associated with diagnosis of periodontitis (p = 0.02). Subgroup analysis by disease phenotype showed associations for the localized AgP (LAgP) group and ?1480C>G and ?6106A>T SNPs (p = 0.007 and 0.010, respectively). Among Caucasians the genotypes IL6 ?1480 CC and ?6106 TT increased the adjusted OR for LAgP (OR = 3.09 and 2.27, respectively). This study supports the hypothesis that IL6 polymorphisms and haplotypes are moderately associated with periodontitis, possibly acting through influencing tissue levels of IL6. This association is stronger for LAgP than for other periodontal disease phenotypes.  相似文献   

15.
ObjectiveTo analyze the relationship of genetic polymorphisms in IL1β, IL6, TNF-α genes and their receptors genes with rheumatoid arthritis (RA) for northwest Han Chinese. This study also explores whether there are gene–gene interactions among these genetic polymorphisms.MethodsA total of 452 patients with RA and 373 matched healthy controls were enrolled to carry out a case-control study for 16 SNPs of IL1B-511 C > T, IL1B-31 T > C, IL1B+3954 C > T, IL1RN T > C, IL6-597 G > A, IL6-572 G > C, IL6-174 G > C, IL6R-183 G > A, IL6R exon2 T > A, IL6R exon1 A > C, TNFA-863 C > A, TNFA-857 C > T, TNFA-308 G > A, TNFA-238 G > A, TNFR1-383 A > C and TNFR2 T676G T > G from seven genes. Genotyping for the SNPs was conducted on the RotorGene 6000 PCR platform using in-house high resolution melting (HRM) approaches. Detection correctness was validated through direct sequencing. Generalized multifactor dimensionality reduction (GMDR) analysis was applied to discover likely gene–gene interaction model among the SNPs.ResultsThe results showed that the genotype distributions of TNFA-308, TNFA-857 and TNFA-863 are significantly different between case and control groups (P = 0.016, P = 0.048 and P = 0.016, respectively). Carriers of TNFA-857 mutant allele conferred risk to RA (OR = 1.525, 95% CI = 1.157–2.009) while those of TNFA-308 and TNFA-863 mutant alleles conferred protection to RA (OR = 0.459, 95% CI = 0.286–0.739; OR = 0.490, 95% CI = 0.329–0.732). GMDR analysis for the SNPs indicated that gene–gene interaction existed among IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857. Thirteen of all genotypes of the six SNPs combination were discovered to have significant distribution difference between RA group and the control.ConclusionsThis study demonstrated that PCR-HRM assay is a highly efficient SNP genotyping method especially for the detection of large-scale samples. The SNPs of TNFA-308 and TNFA-863 are closely associated with RA susceptibility and that gene–gene interactions may occur among the six SNPs of IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857 in RA patients from northwest Chinese Han population, especially these SNPs’ combination genotypes CT/TT/CC/GG/AC/CC, CT/TT/GC/AA/AC/CT and CT/CT/CC/GA/AC/CC to show high risk of RA susceptibility in our study.  相似文献   

16.
Overweight and obesity are associated with chronic and subclinical inflammation due to an imbalance of inflammatory mediators. However, the association with gene polymorphism has been rarely studied in children. The aim of this study was to determine if serum concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) are related to the IL6 rs1800795, IL6 rs2069845 and CRP rs1205 polymorphisms (SNPs) according to body mass index (BMI) in a sample of children and adolescents. A cross-sectional study in 470 students between 7 and 17 years of age of anthropometric characteristics, high sensitivity-CRP (Hs-CRP) and IL-6 levels and three SNPs genotyped. The prevalence ratio of hs-CRP > 3 mg/L in obese individuals was 4.15 (CI 2.43–7.06; p = 0.01), and it was 1.91 (CI 1.03–3.55; p = 0.03) in overweight individuals and 1.74 (CI 1.05–2.88 p = 0.03) in females. Individuals with waist circumference (WC) and body fat percentage (BF%) alterations showed elevated levels of hs-CRP (p = 4.3 × 10−5 and p = 5.3 × 10−6). The combination of any two anthropometric measurement increases CRP levels, especially combinations with obesity body mass index (BMI): BMI + WC and BMI + BF%. Among the overweight/obesity group, T allele carriers of CRP rs1205 showed lower levels of hs-CRP (0.5, IQR = 0.3–1.8 mg/L) than CC homozygotes (1.5, IQR = 0.4–3.4 mg/L, p = 0.018). Additionally, considering subjects with two or three anthropometric alterations for CRP rs1205: rs1205 T allele carriers had lower levels of hs-CRP (0.7, IQR = 0.3–2.7 mg/L) than CC homozygotes (1.2, IQR = 0.5–3.5 mg/L, p = 0.02). In conclusion, carriers of the rs1205/T allele with higher BMIs had lower levels of hs-CRP. Schoolchildren who were overweight/obese had higher levels of CRP and IL-6, whereas individuals with WC and BF% alterations had higher levels of CRP.  相似文献   

17.
Purpose To investigate the role of TSER (TYMS), C677T (MTHFR), Arg72Pro (p53) and C3435T (MDR1) gene polymorphisms in breast cancer patients treated with 5-fluorouracil and cyclophosphamide-based neoadjuvant chemotherapy. Results Observed allelic frequencies were: TSER, (2) 0.54 and (3) 0.46; MTHFR C677T, (C) 0.59 and (T) 0.41; p53 Arg72Pro, (Arg) 0.73 and (Pro) 0.27; MDR1 C3435T, (C) 0.52 and (T) 0.48. MTHFR allele T and p53 allele Pro were strongly associated with toxicity due to chemotherapy (odds ratio, 7.1 (95% confidence interval, 1.4–36.1; p = 0.018) and 7.0 (95% confidence interval, 1.2–40.5; p = 0.029), respectively). Conclusion We introduced new data related to the contribution of p53 codon 72 to toxicity due to 5-fluorouracil and cyclophosphamide-based neoadjuvant chemotherapy in patients with breast cancer.  相似文献   

18.
Although salivary testosterone (T) is often used in clinical studies accuracy is mostly questionable. State of the art data for men is sparse and for women absent. Our objective was to perform a critical evaluation of salivary T (Sal-T) as a method for indirect assessment of serum T using state of the art methods. Saliva was collected via ‘Salivette’ and ‘passive drooling’ methods. Sal-T and free T in serum after equilibrium dialysis were measured by LC-MS/MSResultsEvaluation of Sal-T results versus free T by equilibrium dialysis (ED-T) for men gave: ‘Salivette’ Sal-T = 0.05 + 0.88x ED-T, r = 0.43; ‘passive drooling’ Sal-T = 0.17 + 0.91x ED-T r = 0.71. In women, correlation was comparable but values are higher than free T: ‘passive drooling’ Sal-T = 0.12 + 2.32x ED-T, r = 0.70. The higher than expected T values in saliva, appear to be explained by T binding to salivary proteins. Iso-electric focusing of saliva proteins, followed by fractionation and LC–MS/MS assay of T showed marked testosterone peaks at pH 5.3 and 8.4, providing evidence for T binding in saliva to proteins such as albumin and proline rich protein (PRP).ConclusionsPassive drooling is the collection method of choice for testosterone in saliva. Sal-T is not directly comparable to serum free T due to T binding to saliva proteins, which substantially affects the low Sal-T in women but not the higher Sal-T in healthy adult men.  相似文献   

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20.
We investigated long-term trends in brown macroalgal assemblages inhabiting shallow subtidal rocky bottoms under the influence of thermal effluent discharge from the Brazilian nuclear power plant (BNPP). Three operational periods based on the units of the BNPP were analysed: T0 = pre-operational, between the years 1980 and 1983; T1 = operational period of unit 1, between 1988 and 1999; and T2 = operational period of units 1 and 2, between 2005 and 2012. Using generalized linear mixed models (GLMMs), we found significant declines in the numbers of genera and species over time. More than half of the species of brown macroalgae disappeared during T2. In addition, the numbers of macroalgal genera and species were inversely related to the local surface seawater temperatures. Multivariate analyses revealed a clear separation between the years of T2 and those of T0, indicating long-term changes in the community assemblages. Among the most common species in the area, the frequencies of Canistrocarpus cervicornis, Dictyopteris delicatula, Hincksia mitchelliae, Sargassum spp. and Sphacelaria tribuloides decreased during T2, while Padina gymnospora maintained rather high yearly frequencies during T2 (>40%). Our data suggest that seawater temperatures consistently higher than 30 °C together with peaks higher than 35 °C may have triggered the decline in the brown algae on rocky bottoms under the influence of the BNPP discharge. These results from southern Brazil are consistent with studies from other locations that ascribe changes in seaweed diversity to increasing seawater temperatures, highlighting the sensitivity of brown macroalgae to thermal stress and demonstrating their effectiveness as an ecological indicator for monitoring the effects of nuclear power plant effluents on coastal environments.  相似文献   

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