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1.
Phylogenetic relationships among Chinese species of Morella (Myricaceae) are unresolved. Here, we use restriction site-associated DNA sequencing (RAD-seq) to identify candidate loci that will help in determining phylogenetic relationships among Morella rubra, M. adenophora, M. nana and M. esculenta. Three methods for inferring phylogeny, maximum parsimony (MP), maximum likelihood (ML) and Bayesian concordance, were applied to data sets including as many as 4253 RAD loci with 8360 parsimony informative variable sites. All three methods significantly favored the topology of (((M. rubra, M. adenophora), M. nana), M. esculenta). Two species from North America (M. cerifera and M. pensylvanica) were placed as sister to the four Chinese species. According to BEAST analysis, we deduced speciation of M. rubra to be at about the Miocene-Pliocene boundary (5.28 Ma). Intraspecific divergence in M. rubra occurred in the late Pliocene (3.39 Ma). From pooled data, we assembled 29378, 21902 and 23552 de novo contigs with an average length of 229, 234 and 234 bp for M. rubra, M. nana and M. esculenta respectively. The contigs were used to investigate functional classification of RAD tags in a BLASTX search. Additionally, we identified 3808 unlinked SNP sites across the four populations of M. rubra and discovered genes associated with fruit ripening and senescence, fruit quality and disease/defense metabolism based on KEGG database.  相似文献   
2.
自然产卵场是维持物种延续最关键的栖息地,青海湖裸鲤(Gymnocypris przewalskii)的自然繁殖栖息地状况和生境特征尚缺乏详细的定量研究。以青海湖入湖河流泉吉河为例,在平水期采用现场调查和无人机遥测的方法对青海湖裸鲤的自然产卵场分布及生境状况进行调查,确定其产卵场生境特征参数,建立基于无人机遥测识别产卵场的方法并进行复核验证。结果表明:泉吉河河道形态可分为弯曲型、分汊型和顺直型等三种典型河型,青海湖裸鲤自然产卵场主要分布在弯曲型和分汊型河道中,分汊型河道几乎100%都有产卵场分布,弯曲型河道有70%为产卵场;产卵场河道平均长度(135.13±61.13) m,平均宽度(30.01±17.51) m,平均曲折度1.09±0.07;平均面积(4586.6±4201.61) m2;产卵场常位于缓水浅滩处,平均水深(0.19±0.10) m (范围:0.03-0.44m),平均流速(0.24±0.20) m/s (范围:0.01-0.81m/s),河床质为含有沙粒的卵石(粒径:163-256mm)底质。河道形态、沙洲分布、水深特征等特征参数可作为无人机遥测识别产卵场的判断条件,并实现验证成功。研究结果可为开展整个流域的青海湖裸鲤自然产卵场现状评估及保护对策制定提供技术支撑。  相似文献   
3.
Schizophrenia (SZ) is a common and complex psychiatric disorder that has a significant genetic component. The glutamatergic system is the major excitatory neurotransmitter system in the central nervous system, and is mediated by N-methyl-D-aspartate (NMDA) receptors. Disturbances in this system have been hypothesized to play a major role in SZ pathogenesis. Several studies have revealed that the NMDA receptor subunit 2B (GRIN2B) potentially associates with SZ and its psychiatric symptoms. In this study, we performed a case–control study to identify polymorphisms of the GRIN2B gene that may confer susceptibility to SZ in the Han Chinese population. Thirty-four single nucleotide polymorphisms (SNPs) were genotyped in 528 paranoid SZ patients and 528 control subjects. A significant association was observed in allele and genotype between SZ and controls at rs2098469 (χ2 = 8.425 and 4.994; p = 0.025 and 0.014, respectively). Significant associations were found in the allele at rs12319804 (χ2 = 4.436; p = 0.035), as well as in the genotype at rs12820037 and rs7298664 between SZ and controls (χ2 = 11.162 and 38.204; p = 0.003 and 4.27×10-8, respectively). After applying the Bonferroni correction, rs7298664 still had significant genotype associations with SZ (p = 1.71×10-7). In addition, rs2098469 genotype and allele frequencies, and 12820037 allele frequencies were nominally associated with SZ. Three haplotypes, CGA (rs10845849—rs12319804—rs10845851), CC (rs12582848—rs7952915), and AAGAC (rs2041986—rs11055665—rs7314376—rs7297101—rs2098469), had significant differences between SZ and controls (χ2 = 4.324, 4.582, and 4.492; p = 0.037, 0.032, and 0.034, respectively). In addition, three SNPs, rs2098469, rs12820037, and rs7298664, were significantly associated with cognition factors PANSS subscores in SZ (F = 16.799, 7.112, and 13.357; p = 0.000, 0.017, and 0.000, respectively). In conclusion, our study provides novel evidence for an association between GRIN2B polymorphisms and SZ susceptibility and symptoms in the Han Chinese population.  相似文献   
4.

Objective

The present study aimed to evaluate the efficacy and safety of adjunctive aripiprazole treatment in schizophrenia patients with risperidone-induced hyperprolactinemia.

Methods

One hundred and thirteen patients who were receiving a stable dose of risperidone were randomly assigned to either adjunctive aripiprazole treatment (10 mg/day) (aripiprazole group) or no additional treatment (control group) at a 1:1 ratio for 8 weeks. Schizophrenia symptoms were measured using the Positive and Negative Syndrome Scale (PANSS). Rating scales and safety assessments (RSESE, BARS, UKU) were performed at baseline and at weeks 4 and 8. Serum levels of prolactin were determined at baseline and at weeks 2, 4, 6 and 8. Metabolic parameters were determined at baseline and again at weeks 4 and 8.

Results

One hundred and thirteen patients were enrolled in this study, and 107 patients completed the study (54 in the aripiprazole group, and 53 in the control group). PANSS-total scores in the aripiprazole group decreased significantly at week 4 (P = 0.003) and week 8 (P = 0.007) compared with the control group. PANSS-negative scores in the aripiprazole group also decreased significantly at week 4 (P = 0.005) and week 8 (P< 0.001) compared with the control group. Serum levels of prolactin in the aripiprazole group decreased significantly at week 2 (P< 0.001), week 4 (P< 0.001), week 6 (P< 0.001) and week 8 (P< 0.001) compared with the control group. There were no significant differences in changes of Fasting Plasma Glucose, Total cholesterol, Triglycerides and High Density Lipoprotein within each group at week 4 and 8 execpt low density lipoproteins. There was no significant difference in the incidence of adverse reactions between the two groups.

Conclusions

Adjunctive aripiprazole treatment may be beneficial in reducing serum levels of prolactin and improving negative symptoms in schizophrenia patients with risperidone-induced hyperprolactinemia.

Trial Registration

chictr.org ChiCTR-IOR-15006278  相似文献   
5.
Zhang  Yamin  Ren  Hongyan  Wang  Qiang  Deng  Wei  Yue  Weihua  Yan  Hao  Tan  Liwen  Chen  Qi  Yang  Guigang  Lu  Tianlan  Wang  Lifang  Zhang  Fuquan  Yang  Jianli  Li  Keqing  Lv  Luxian  Tan  Qingrong  Zhang  Hongyan  Ma  Xin  Yang  Fude  Li  Lingjiang  Wang  Chuanyue  Zhang  Dai  Zhao  Liansheng  Wang  Huiyao  Li  Xiaojing  Guo  Wanjun  Hu  Xun  Tian  Yang  Ma  Xiaohong  Li  Tao 《中国科学:生命科学英文版》2019,62(4):535-543
Antipsychotic-induced metabolic disturbance(AIMD) is a common adverse effect of antipsychotics with genetics partly underpinning variation in susceptibility among schizophrenia patients. Melanocortin4 receptor(MC4 R) gene, one of the candidate genes for AIMD, has been under-studied in the Chinese patients. We conducted a pharmacogenetic study in a large cohort of Chinese patients with schizophrenia. In this study, we investigated the genetic variation of MC4 R in Chinese population by genotyping two SNPs(rs489693 and rs17782313) in 1,991 Chinese patients and examined association of these variants with the metabolic effects that were often observed to be related to AIMD. Metabolic measures, including body mass index(BMI), waist circumference(WC), glucose, triglyceride, high-density lipoprotein(HDL), and low-density lipoprotein(LDL) levels were assessed at baseline and after 6-week antipsychotic treatment. We found that interaction of SNP×medication status(drug-na?ve/medicated) was significantly associated with BMI, WC, and HDL change %, respectively. Both SNPs were significantly associated with baseline BMI and WC in the medicated group. Moderate association of rs489693 with WC, Triglyceride, and HDL change % were observed in the whole sample. In the drug-na?ve group, we found recessive effects of rs489693 on BMI gain more than 7%, WC and Triglyceride change %, with AA incurring more metabolic adverse effects. In conclusion, the association between rs489693 and the metabolic measures is ubiquitous but moderate. Rs17782313 is less involved in AIMD. Two SNPs confer risk of AIMD to patients treated with different antipsychotics in a similar way.  相似文献   
6.
本文报告,pH9.6碳酸缓冲液对甲3型流感病毒的血凝滴度有明显降低作用,对甲1型和乙型仅有轻微影响,对甲2型的影响则介于两者之间。用不同pH的碳酸缓冲液、磷酸缓冲液及盐水等,测定甲3型流感病毒的血凝滴度,结果表明高pH对其有明显影响。分别具有甲3、甲2或甲1血凝素的重组株,在pH9.6碳酸缓冲液中,其血凝素的稳定性也和上述结果一样,即具有甲3血凝素的重组株,其血凝素对pH9.6碳酸缓冲液最敏感;甲1重组株的血凝素较稳定:而具有甲2血凝素的重组株则介于两者之间。利用此pH特征测定新分离的经血凝抑制试验鉴定为甲3型和乙型流感病毒,得到同样结果,因此有可能利用此pH特征对新分离的甲3型流感病毒进行初步鉴定。  相似文献   
7.
The purpose of this study was to investigate the change in plasma protein expression in first episode schizophrenia after an 8-week treatment with risperidone, and to explore potential biomarkers for metabolic side effects associated with risperidone treatment. Eighty first-episode schizophrenia patientswere enrolled in the study. Fifteen of the 80 patients were randomly selected to undergo proteomic analysis. Plasma proteins were obtained before and after the 8-week risperidone treatment, and measured using two-dimensional gel electrophoresis (2-DE), Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry(MALDI-TOF/TOF) and peptide mass fingerprinting.Proteins with the highest fold changes after risperidone treatment were then measured for all 80 patients using enzyme linked immunosorbent assay (ELISA). The relationship between changes in plasma protein levels and changes in metabolic parameters after risperidone treatment was examined. In 15 randomly selected patients, approximately 1,500 protein spots were detected in each gel by 2-DE. Of those proteins, 22 spots showed significant difference in abundance after risperidone treatment (p''s<0.05). After MALDI-TOF peptide mass fingerprinting, apolipoprotein A-I (APOA-I) and Guanine Nucleotide Binding Protein, Alpha Stimulating (GNAS), were found to have the highest fold changes.The content of APOA-I was significantly increased, and the content of GNAS was significantly decreased after risperidone treatment (p''s<0.05). The analysis in the entire study sample showed similar findings in changes of APOA-I and GNAS after risperidone treatment. Further analysis showed significant relationships between changesin APOA-1 and changes in triglyceride, total cholesterol, and body mass index after controlling for age, gender and family history of diabetes. Similar analysis showed a trend positive relationship between changes in GNAS and changes in BMI. Using proteomic analysis, the study suggested that APOA-I might be a novel biomarkers related to metabolic side effects in first episode schizophrenia treated with risperidone.  相似文献   
8.
9.

Background

The key factors which support re-expansion of beta cell numbers after injury are largely unknown. Insulin-like growth factor II (IGF-II) plays a critical role in supporting cell division and differentiation during ontogeny but its role in the adult is not known. In this study we investigated the effect of IGF-II on beta cell regeneration.

Methodology/Principal Findings

We employed an in vivo model of ‘switchable’ c-Myc-induced beta cell ablation, pIns-c-MycERTAM, in which 90% of beta cells are lost following 11 days of c-Myc (Myc) activation in vivo. Importantly, such ablation is normally followed by beta cell regeneration once Myc is deactivated, enabling functional studies of beta cell regeneration in vivo. IGF-II was shown to be re-expressed in the adult pancreas of pIns-c-MycERTAM/IGF-II+/+ (MIG) mice, following beta cell injury. As expected in the presence of IGF-II beta cell mass and numbers recover rapidly after ablation. In contrast, in pIns-c-MycERTAM/IGF-II+/− (MIGKO) mice, which express no IGF-II, recovery of beta cell mass and numbers were delayed and impaired. Despite failure of beta cell number increase, MIGKO mice recovered from hyperglycaemia, although this was delayed.

Conclusions/Significance

Our results demonstrate that beta cell regeneration in adult mice depends on re-expression of IGF-II, and supports the utility of using such ablation-recovery models for identifying other potential factors critical for underpinning successful beta cell regeneration in vivo. The potential therapeutic benefits of manipulating the IGF-II signaling systems merit further exploration.  相似文献   
10.
物质流、能量流、信息流是生态系统过程研究中的三大主题。然而,在流域生态学研究中,有关信息流的研究一直缺位。为了推动流域信息流研究,从生物信息流切入,提出"流域生物信息流"概念,将其定义为"生物信息依托于流域生态系统过程在不同空间和系统之间进行传递、交流、作用、反馈的路径、过程与控制",并将其研究内容拟定为主要关注于水陆间、干支流间、上下游间、不同生态斑块间的流域生物信息流及其周期性节律和趋势性变迁,以及地貌、水文、人类活动等对这些生物信息流的影响等。然后,以青藏高原上青海湖重要入湖河流--沙柳河的河流水体微生物和岸带土壤微生物为研究对象,利用环境DNA技术,对沙柳河流域的自然径流驱动的流域生物信息流进行量化研究。结果表明(1)岸带土壤到水体的流域生物信息流主要由地表表面流、地下潜流等驱动,并受环境过滤效应影响,其输移效率降雨天约为62.76%、晴天约为44.16%,其中输移能力降雨天约为68.49%、晴天约为56.82%,环境过滤效应降雨天约为8.38%、晴天约为22.28%;(2)水体上游到下游的流域生物信息流主要由河川径流驱动,并受衰减效应影响,其基础综合输移效率约为97.41%/km,其中径流输移能力约为99.42%/km,无效流域生物信息流占比约为43.46%,无效流域生物信息流的半衰距离约为14.52 km;(3)降雨通过增加地表表面流等的冲蚀搬运能力并削弱环境过滤效应,促使岸带土壤到水体的流域生物信息流输移能力和输移效率增大;(4)流域生物信息流的输入在一定程度上增加了输入地的可检出生物多样性,但这种增加对于流水生态系统来讲是非累积的。  相似文献   
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