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1.
Zhonghua Yi Xue Za Zhi ; 99(23): 1805-1808, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31207692

RESUMO

Objective: To investigate the surgical nuances and efficacy of microvascular decompression in patients with coexistent hemifacial spasm and ipsilateral trigeminal neuralgia. Methods: Seventeen patients suffered from coexistent hemifacial spasm and ipsilateral trigeminal neuralgia were treated in Department of Neurosurgery, Henan Provincial People's Hospital from January 2008 to September 2017. The medical recorders, intra-operative findings and postoperative follow-up results of these patients were reviewed, and the surgical strategies and therapeutic effects of these patients were summarized. Results: The offending vessels of the patients coexistent hemifacial spasm and ipsilateral trigeminal neuralgia were complex. The tortuous vertebral artery shifted to the suffered side in nine patients (52.9%), among which seven cases had vertebral artery as the offending vessel or indirect offending vessel compressing facial nerve and/or trigeminal nerve. The effective rate was 100%,the cure rate was 94.1%, and the immediate relief rate was 82.4%. All the patients were followed up for more than one year without recurrence. Conclusion: Patients with coexistent hemifacial spasm and ipsilateral trigeminal neuralgia with tortuous vertebral artery shifted to the affected side were more common. Good surgical nuances and strategies in microvascular decompression are the guarantee of successful surgery.


Assuntos
Espasmo Hemifacial , Cirurgia de Descompressão Microvascular , Neuralgia do Trigêmeo , Humanos , Resultado do Tratamento , Nervo Trigêmeo , Artéria Vertebral
2.
Zhonghua Yi Xue Za Zhi ; 97(31): 2451-2453, 2017 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-28835048

RESUMO

Objective: To compare the difference of hearing loss after microvascular decompression for hemifacial spasm between control and experimental groups, and to explore the possible causes. Methods: A retrospective analysis including 443 patients was performed, including 203 cases of group A (before the operation was improved) and 240 cases of group B (after the operation was improved). Chi-square test was used to compare the rate of hearing loss. Results: There were 18(8.9%) cases with postoperative hearing loss in group A, including 9 cases of conductive hearing loss and 9 cases of sensorineural hearing loss.While 2 cases of conductive hearing loss and 3 cases of sensorineural hearing loss occurred in group B. Conductive hearing loss and sensorineural hearing loss of two groups had the significant deference (P=0.015 and P=0.04). Conclusion: The type of hearing loss after microvascular decompression for hemifacial spasm included conductive and sensorineural hearing loss.It could be reduced by early closing of the mastoid air chamber, avoiding continuous traction of the cerebellum, avoiding excessive irrigation and exhaust, and intraoperative auditory brainstem evoked potential monitoring.


Assuntos
Perda Auditiva , Espasmo Hemifacial , Cirurgia de Descompressão Microvascular , Potenciais Evocados Auditivos do Tronco Encefálico , Humanos , Estudos Retrospectivos , Resultado do Tratamento
3.
J Eur Acad Dermatol Venereol ; 27(9): 1168-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22364124

RESUMO

BACKGROUND: Blue light in the 400-420 nm range has been shown to reduce the levels of Propionibacterium acnes (P. acnes) in the skin. P. acnes has been postulated to be a critical trigger for inflammatory acne. Thus, treatment with 420 nm-intense pulsed light should reduce inflammatory activity in acne. AIM: To evaluate the clinical and histological effects of 420 nm-intense pulsed light treatment on acne in animal model. METHOD: Inflammation acne animal model was constructed by intradermal injection of P. acnes of rat auricular. Levels of tumour necrosis factor alpha (TNF-α) and matrix metalloproteinase 2 (MMP-2), markers of inflammation implicated in acne, were assessed in treated and untreated animals by immunohistochemistry and quantitative polymerase chain reaction (PCR). RESULT: Treatment with 420 nm intense pulsed light led to marked improvement after 6 biweekly treatments. Immunohistochemistry and PCR showed that TNF-α and MMP-2 levels correlated with the extent of acneiform activity and were reduced by treatment with 420 nm light. CONCLUSION: A 420-nm intense pulsed light may exert its beneficial effects on inflammatory acne by reducing the levels of P. acnes and secondarily reducing inflammation induced by the bacteria.


Assuntos
Acne Vulgar/terapia , Terapia de Luz Pulsada Intensa , Animais , Modelos Animais de Doenças , Feminino , Ratos , Ratos Sprague-Dawley
4.
Sci Rep ; 11(1): 20366, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645959

RESUMO

Classical laws of friction suggest that friction force is proportional to the normal load and independent of the nominal contact area. As a great improvement in this subject, it is now widely accepted that friction force is proportional to the real contact area, and much work has been conducted based on this hypothesis. In present study, this hypothesis will be carefully revisited by measuring the friction force and real contact area in-site and real-time at both normal loading and unloading stages. Our experiments reveal that the linear relation always holds between friction force and normal load. However, for the relation between friction force and real contact area, the linearity holds only at the loading stage while fails at the unloading stage. This study may improve our understanding of the origin of friction.

5.
Artigo em Chinês | MEDLINE | ID: mdl-30808132

RESUMO

Objective: To explore the value of 1ean nystagmus and sitting to supine positioning nystagmus in the diagnosis of horizontal semicircular canal benign paroxysmal positional vertigo. Method: One hundred cases of patients with definitive diagnosis of horizontal semicircular canal benign paroxysmal positional vertigo were tested by 1ean nystagmus and sitting to supine positioning nystagmus and supine roll test. The affected side was recorded according to the nystagmus direction. After diagnosis, they were treated with canalith repositioning procedure. The canalith repositioning procedure was made according to the supine roll test result when 1ean nystagmus and sitting to supine positioning nystagmuscannot be induced. Furthermore,the canalith repositioning procedure was made according to the1ean nystagmus and sitting to supine positioning nystagmuswhenthe supine roll test cannot diagnose. The patients with canalolithiasis were randomly divided into two groups when both 1ean nystagmus and sitting to supine positioning nystagmusand the supine roll test can be induced. One group was treated with canalith repositioning procedure based on results of supine roll test and the other group was treated based on the results of1ean nystagmus and sitting to supine positioning nystagmus. The detection rate and diagnostic coincidence rate of 1ean nystagmus and sitting to supine positioning nystagmus were calculated and the shortterm outcome were evaluated one day after treatment. Result: The detection rate of 1ean nystagmus and sitting to supine positioning nystagmus was 83% and the coincidence rate with the roll test was 90.1%,respectively. There was no significant statistical difference between the treatment effect according to lean nystagmus and sitting to supine positioning nystagmus and supine roll test. Conclusion: Lean nystagmus and sitting to supine positioning nystagmus cannot be used alone in the diagnosis ofhorizontal semicircular canal benign paroxysmal positional vertigo. They need to be combined with supine roll test. However, when the supine roll test is difficult to demonstrate the affected side, it can be used as an auxiliary diagnostic method. When the results of 1ean nystagmus and sitting to supine positioning nystagmusand the supine roll test are inconsistent, repeat the test and conduct a comprehensive assessment to avoid missed diagnosis and misdiagnosis..


Assuntos
Vertigem Posicional Paroxística Benigna , Nistagmo Patológico , Posicionamento do Paciente , Vertigem Posicional Paroxística Benigna/diagnóstico , Humanos , Canais Semicirculares , Postura Sentada
6.
Artigo em Chinês | MEDLINE | ID: mdl-31550769

RESUMO

Acid-sensing ion channels are a class of extracellular H(+) activated cation channels, belonging to the amiloride-sensitive epithelial Na(+) channel/degenerin (ENaC/DEG) superfamily. During extracellular acidification, the channels are activated and produce corresponding action potential. Acid-sensing ion channels are extensively expressed in the peripheral and central nervous system. It plays an important in synaptic plasticity, mechanical sensation, injury sensation related to acidosis of local tissues, acid reception and retinal regulation. This article reviews the expression, biological characteristics and functions of acid-sensing ion channels in cochlea, vestibular tissue and auditory center, so as to improve the understanding of physiology and pathophysiology of auditory system.


Assuntos
Canais Iônicos Sensíveis a Ácido , Córtex Auditivo , Cóclea , Vestíbulo do Labirinto , Canais Iônicos Sensíveis a Ácido/genética , Canais Iônicos Sensíveis a Ácido/metabolismo , Córtex Auditivo/fisiologia , Cóclea/fisiologia , Humanos , Sensação , Vestíbulo do Labirinto/fisiologia
7.
Artigo em Chinês | MEDLINE | ID: mdl-29871326

RESUMO

Objective:To explore the clinical value of rolling test(HRT), bow and lean test(BLT) and subjective vertigo sensation(SVS) for affected side localization of patients with horizontal semicircular canal benign paroxysmal positional vertigo(HSC-BPPV).Method:One hundred and thirty-eight patients(94 HSC-Can and 44 HSC-Cup)with HSC-BPPV were enrolled. Patients were tested with HRT and then were asked about SVS, followed by BLT. According to the results of HRT, SVS and BLT, HSC-Can and HSC-Cup were repositioned by Barbecue method and modified Kim method respectively. The detection rate of the affected side of HRT, BLT, SVS and the curative effect were analyzed. Result:In 94 HSC-Can patients and 44 HSC-Cup patients,BN and / or LN were induced by BLT to be 81.91% and 84.09% respectively. HRT induced bilateral asymmetric nystagmus 90.43%, 88.64%, SVS told vertigo symptoms worse side 60.64%,63.64%. There was no significant difference in the detection rate of HRT and BLT(P>0.05),but have significant difference with SVS(P<0.05). Excluding four patients in whom the comparison among HRT,BLT,SVS were inconclusive,we compared the curative effect of first treatment in 92 HSC-Can patients and 42 HSC-Cup patients. The curative effect of HRT positive only were 66.67% and 60.00% respectively , BLT positive only were 71.43% and 66.67% respectively , HRT and BLT both positive with ipsilateral affected side were 70.37% and 65.50% respectively , HRT and BLT both positive with contralateral affected side were 37.50% and 30.00% respectively. The curative effect of HRT positive only and BLT positive only had no significant difference with that of HRT and BLT both positive with ipsilateral affected side , but they both had significant difference with that of HRT and BLT both positive with contralateral affected side . Conclusion:HRT is the most effective method for detecting affected side of HSC-BPPV, but BLT and SVS also have auxiliary diagnostic value as HSC-BPPV localization method.


Assuntos
Vertigem Posicional Paroxística Benigna/diagnóstico , Nistagmo Patológico/fisiopatologia , Postura/fisiologia , Canais Semicirculares/fisiopatologia , Vertigem Posicional Paroxística Benigna/fisiopatologia , Tontura , Humanos , Sensação
8.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 31(24): 1919-1922, 2017 Dec 20.
Artigo em Chinês | MEDLINE | ID: mdl-29798316

RESUMO

Objective:To offer the objective evidences for the diagnosis by analyzing anxiety and depression among patients with sudden deafness and vertigo and their possible causes. Method:Eighty patients with sudden deafness and vertigo of single ear as the observation group; 80 patients with sudden deafness without vertigo and 60 healthy people as control group.Hamilton anxiety scale (HAMA), Hamilton depression scale (HAMD) are used for quantitative analysis and compare the results of each group score. Result:①The HAMA score of the deafness group with vertigo was significantly higher than that of the group without vertigo and the healthy group (P<0.01). The HAMD score of the deafness group with vertigo was significantly higher than that of the group without vertigo and the healthy group (P<0.01). ②There was correlation between HAMA and sex, age, duration of dizziness, tinnitus, DHI and efficacy grading (P<0.05). There was no correlation between HAMA and the mean hearing threshold, urban and rural distribution, ear fullness (P> 0.05). There was a correlation between HAMD and sex, age, tinnitus, DHI and efficacy grading (P<0.05). There was no correlation between HAMD and the mean hearing threshold, duration of dizziness, urban and rural distribution, ear fullness (P>0.05). Conclusion:There are anxiety and depression in patients with deafness and vertigo. It is mainly related to sex, age, dizziness duration, tinnitus, DHI and grade of efficacy. It is necessary to pay attention to the mental state of patients in clinical treatment. Psychological counseling or treatment can be used to improve clinical efficacy.


Assuntos
Ansiedade , Depressão , Perda Auditiva Súbita/psicologia , Vertigem/psicologia , Tontura , Humanos
9.
Genetics ; 162(4): 1885-95, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12524357

RESUMO

We introduced an experimental design that produced an "immortalized F(2)" population allowing for complete dissection of genetic components underlying quantitative traits. Data for yield and three component traits of the immortalized F(2) were collected from replicated field trials over 2 years. Using 231 marker loci, we resolved the genetic effects into individual components and assessed relative performance of all the genotypes at both single- and two-locus levels. Single-locus analysis detected 40 QTL for the four traits. Dominance effects for about one-half of the QTL were negative, resulting in little "net" positive dominance effect. Correlation between genotype heterozygosity and trait performance was low. Large numbers of digenic interactions, including AA, AD, and DD, were detected for all the traits, with AA as the most prevalent interaction. Complementary two-locus homozygotes frequently performed the best among the nine genotypes of many two-locus combinations. While cumulative small advantages over two-locus combinations may partly explain the genetic basis of heterosis of the hybrid as double heterozygotes frequently demonstrated marginal advantages, double heterozygotes were never the best genotypes in any of the two-locus combinations. It was concluded that heterozygotes were not necessarily advantageous for trait performance even among genotypes derived from such a highly heterotic hybrid.


Assuntos
Oryza/genética , Epistasia Genética , Ligação Genética , Marcadores Genéticos , Heterozigoto , Homozigoto , Vigor Híbrido , Hibridização Genética , Modelos Genéticos , Oryza/crescimento & desenvolvimento , Locos de Características Quantitativas
10.
Yi Chuan Xue Bao ; 28(5): 439-46, 2001 May.
Artigo em Chinês | MEDLINE | ID: mdl-11441657

RESUMO

The development of molecular genetic linkage map has accelerated the identification and mapping of genomics regions controlling quantitative trait loci. A recombinant inbred line population derived from Zhenshan 97/Minghui 63 was grown in two years. Mixed linear model approach was used to jointly identify QTLs and QTL x environment interactions for five panicle characteristics. Ten, three, six, eight and seven QTLs were detected for spiketets per panicle, grains per panicle, seed setting, panicle length and panicle setting density, respectively. They collectively explained 29.13%, 19.2%, 29.46%, 26.39% and 35.76% of phenotypic variations for these traits, respectively. For the five traits, QTLs with increasing effects and decreasing effects could be simultaneously identified in high value parent and low value parent. QTLs for correlative traits clustering located in the similar regions. One QTL for panicle length, two QTLs for spikelets per panicle and three QTLs for seed setting performed significant interactions with environment. The contributions from interactions were slightly larger than that from the QTLs involved in the interactions. No QTL x environment interaction was detected for traits with high heritabilities such as grains per panicle and panicle setting density.


Assuntos
Mapeamento Cromossômico , Oryza/genética , Característica Quantitativa Herdável , Meio Ambiente
11.
Theor Appl Genet ; 116(6): 789-96, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18219477

RESUMO

In our previous studies, one putative QTL affecting number of spikelets per panicle (SPP) was identified in the pericentromeric region of rice chromosome 7 using a recombinant inbred population. In order to define the QTL (qSPP7), RI50, a recombinant inbred line with 70% of genetic background same as the female parent of Zhenshan 97, was selected to produce near-isogenic lines for the target region in the present study. In a BC(2)F(2) population consisting of 190 plants, the frequency distribution of SPP was shown to be discontinuous and followed the expected Mendelian ratios (1:2:1 by progeny test) for single locus segregation. qSPP7 was mapped to a 0.4 cM region between SSR marker RM3859 and RFLP marker C39 based on tests of the BC(2)F(2) population and its progeny. Its additive and dominant effects on SPP were 51.1 and 24.9 spikelets, respectively. Of great interest, the QTL region also had effects on grain yield per plant (YD), 1,000 grain weight (GW), tillers per plant (TPP) and seed setting ratio (SR). Significant correlations were observed between SPP and YD (r = 0.66) and between SPP and SR (r = -0.29) in the progeny test. 1082 extremely small panicle plants of a BC(3)F(2) population containing 8,400 individuals were further used to fine map the QTL. It turns out that qSPP7 co-segregated with two markers, RM5436 and RM5499 spanning a physical distance of 912.4 kb. Overall results suggested that recombination suppression occurred in the region and positional cloning strategy is infeasible for qSPP7 isolation. The higher grain yield of Minghui 63 homozygote as compared to the heterozygote suggested that Minghui 63 homozygote at qSPP7 in hybrid rice could further improve its yield.


Assuntos
Mapeamento Cromossômico , Cromossomos de Plantas/genética , Topos Floridos/genética , Oryza/genética , Locos de Características Quantitativas , Topos Floridos/anatomia & histologia , Topos Floridos/crescimento & desenvolvimento , Genes de Plantas , Ligação Genética , Marcadores Genéticos
12.
Theor Appl Genet ; 115(4): 463-76, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17593343

RESUMO

A recombinant inbred line population derived from a cross between Zhenshan 97 and Delong 208 was used to analyze the genetic basis of the cooking and eating quality of rice as reflected by 17 traits (or parameters). These traits include amylose content (AC), gel consistency (GC), alkali spreading value (ASV), cooked rice elongation (CRE), and 13 parameters from the viscosity profile. All the traits, except peak paste viscosity (PKV), time needed from gelatinization to peak (BAtime), and CRE, can be divided into two classes according to their interrelationship. The first class consists of AC, GC, and most of the paste viscosity parameters that form a major determinant of eating quality. The second class includes ASV, pasting temperature (Atemp) and pasting time (Atime), which characterize cooking process. We identified 26 QTL (quantitative trait locus or loci) in 2 years; nine QTL clusters emerged. The two major clusters, which correspond to the Wx and Alk loci, control the traits in the first and second classes, respectively. Some QTL are co-located for the traits belonging to the same class and also for the traits to a different class. The Wx locus also affects on ASV while the Alk locus also makes minor contributions to GC and some paste viscosity parameters. The QTL clusters on other chromosomes are similar to the Wx locus or Alk locus, although the variations they explained are relatively minor. QTL for CRE and PKV are dispersed and independent of the Wx locus. Low paste viscosity corresponds to low AC and soft gel, which represents good eating quality for most Chinese consumers; high ASV and low Atemp, together with reduced time to gelatinization and PKV, indicate preferred cooking quality. The genetic basis of Atemp, Atime, BAtime, peak temperature, peak time, paste viscosity at 95 degrees C, and final paste viscosity is newly examined to reveal a complete and dynamic viscosity profile.


Assuntos
Oryza/genética , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Culinária , DNA de Plantas/genética , Alimentos , Repetições Minissatélites , Oryza/anatomia & histologia , Oryza/fisiologia , Fenótipo , Polimorfismo Genético , Locos de Características Quantitativas , Viscosidade
13.
Theor Appl Genet ; 110(8): 1445-52, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15841361

RESUMO

Amylose content (AC), gel consistency (GC) and gelatinazation temperature (GT) are three important traits that influence the cooking and eating quality of rice. The objective of this study was to characterize the genetic components, including main-effect quantitative trait loci (QTLs), epistatic QTLs and QTL-by-environment interactions (QEs), that are involved in the control of these three traits. A population of doubled haploid (DH) lines derived from a cross between two indica varieties Zhenshan 97 and H94 was used, and data were collected from a field experiment conducted in two different environments. A genetic linkage map consisting of 218 simple sequence repeat (SSR) loci was constructed, and QTL analysis performed using QTLMAPPER 1.6: resolved the genetic components into main-effect QTLs, epistatic QTLs and QEs. The analysis detected a total of 12 main-effect QTLs for the three traits, with a QTL corresponding to the Wx locus showing a major effect on AC and GC, and a QTL corresponding to the Alk locus having a major effect on GT. Ten digenic interactions involving 19 loci were detected for the three traits, and six main-effect QTLs and two pairs of epistatic QTLs were involved in QEs. While the main-effect QTLs, especially the ones corresponding to known major loci, apparently played predominant roles in the genetic basis of the traits, under certain conditions epistatic effects and QEs also played important roles in controlling the traits. The implications of the findings for rice quality improvement are discussed.


Assuntos
Meio Ambiente , Epistasia Genética , Alimentos , Temperatura Alta , Oryza/genética , Fenótipo , Locos de Características Quantitativas , Amilose/metabolismo , Mapeamento Cromossômico , Cruzamentos Genéticos , Repetições Minissatélites/genética , Oryza/metabolismo
14.
Theor Appl Genet ; 106(4): 649-58, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12595994

RESUMO

Source, sink, and translocation capacity of assimilates play important roles during the formation of grain yield. The present study was conducted to characterize the genetic bases of traits representing source, sink and transport tissue, and their relationships with yield traits in rice, by analyzing QTLs for these traits and various ratios among them. The genetic materials were a recombinant inbred population derived from a cross between two indica cultivars Zhenshan 97 and Minghui 63, the parents of the most-widely grown hybrid rice in China. Using a linkage map that covers a total of 1,796 cM based on 221 molecular marker loci, a total of 81 QTLs were identified for the 15 traits studied (three leaf areas as the source, total spikelets per panicle as the sink, the number of large vascular bundles in the stem as transport tissue, three source to sink ratios, three transport tissue to source ratios, one transport tissue to sink ratio and three yield traits). The amount of variation explained by individual QTLs ranged from 1.12% to 24.14%. Five QTLs were identified to show interaction effects with the environment, which explained from 3.19% to 9.15% of the variation. The results showed that close linkage or pleiotropy is the genetic basis for the correlations of grain yield traits with source, sink, transport tissue and the various ratios among them. Of the 25 QTLs identified for source-sink-transport tissue trait, and 43 for various ratios, 8 and 22 QTLs, respectively, were mapped to the similar genomic blocks harboring QTLs for yield traits, especially for grain weight. Co-location of QTLs for yield traits with those for ratios among source, sink and transport tissue may provide a genetic explanation for the physiological expression of yield traits, and also suggest that improvement in ratios among source, sink and transport tissue may result in improvement in yield potential.


Assuntos
Oryza/genética , Oryza/fisiologia , Locos de Características Quantitativas , Quimera , Mapeamento Cromossômico , Cruzamentos Genéticos , Ligação Genética , Marcadores Genéticos , Modelos Genéticos , Fenótipo , Especificidade da Espécie
15.
Zhongguo Yao Li Xue Bao ; 13(3): 218-22, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1442102

RESUMO

Acute cerebral ischemia and reperfusion injury of rabbits was produced by permanently occluding the vertebral arteries and temporarily clamping the common carotid arteries for 30 min. Phencyclidine [1-(phenylcyclohexyl)piperidine, PCP] 40-80 micrograms.kg-1 icv 30 min before ischemia significantly attenuated the decrease of the total power of electroencephalogram (EEG) within 30 min of ischemia and improved the recovery of brain electric activity following reperfusion. PCP 20-80 micrograms.kg-1 dose-dependently suppressed the creatine kinase (CK) release during cerebral ischemia and reperfusion, and PCP 40-80 micrograms.kg-1 reduced brain ischemic damage. These improvements indicated that PCP has protective effects on acute cerebral ischemia and reperfusion injury.


Assuntos
Isquemia Encefálica/prevenção & controle , Fenciclidina/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Isquemia Encefálica/líquido cefalorraquidiano , Isquemia Encefálica/fisiopatologia , Creatina Quinase/líquido cefalorraquidiano , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Feminino , L-Lactato Desidrogenase/líquido cefalorraquidiano , Masculino , Neurônios/efeitos dos fármacos , Fenciclidina/uso terapêutico , Coelhos , Traumatismo por Reperfusão/líquido cefalorraquidiano , Traumatismo por Reperfusão/fisiopatologia
16.
Theor Appl Genet ; 109(3): 640-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15103410

RESUMO

A better understanding of the genetics of seedling characteristics in rice could be helpful in improving rice varieties. Zhenshan 97 and Minghui 63, the parents of Shanyou 63, an elite hybrid developed during the last decade in China, vary greatly with respect to their physiological and morphological traits at the seedling growth stage. In this study, we used a population of 240 recombinant inbred lines derived from a cross between Zhenshan 97 and Minghui 63 to identify quantitative trait loci (QTL) for seedling characteristics. All plant material was grown in hydroponic culture. Data for the following characters were collected at 30 days and 40 days post-sowing: plant height, shoot dry matter weight (SDW), maximum root length, root dry weight (RDW), total dry weight, and root-shoot ratio (the ratio of SDW to RDW). Analysis using composite interval mapping detected 16 QTL for the six traits in 30-day-old seedlings. Of these 16 QTL, Minghui 63 alleles increased trait values at only two of them. The QTL in the vicinity of R3166 on chromosome 5 simultaneously influenced PH, SDW, MRL, RDW, and TDW in the same direction. Twenty QTL were detected for the same traits in the 40-day-old seedlings. However, at this stage Minghui 63 alleles increased trait values at eight QTL. The QTL linked to R3166 also affected PH, SDW, MRL, RDW, and TDW. Only four QTL were common to the two stages. These results clearly indicate that different genes (QTL) control the same traits during different time intervals. Zhenshan 97 alleles had positive effects during the first 30 days of seedling growth, but thereafter the positive effects of Minghui 63 alleles on seedling growth gradually became more pronounced.


Assuntos
Oryza/genética , Fenótipo , Locos de Características Quantitativas/genética , Biomassa , China , Mapeamento Cromossômico , Cruzamentos Genéticos , Hidroponia , Oryza/crescimento & desenvolvimento , Plantas Geneticamente Modificadas
17.
Theor Appl Genet ; 99(3-4): 642-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22665200

RESUMO

The cooking and eating quality of the rice grain is one of the most serious problems in many rice-producing areas of the world. In this study, we conducted a molecular marker-based genetic analysis of three traits, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT), that are the most important constituents of the cooking and eating quality of rice grains. The materials used in the analysis included F(2) seeds, an F(2:3) population, and an F(9) recombinant inbred-line population from a cross between the parents of 'Shanyou 63', the most widely grown hybrid in rice production in China. Segregation analyses of these three generations showed that each of the three traits was controlled by a single Mendelian locus. Molecular marker-based QTL (quantitative trait locus) analyses, both by one-way analysis of variance using single marker genotypes and by whole-genome scanning with MAPMAKER/QTL, revealed a single locus that controls the expression of all three traits. This locus coincided with the Wx region on the short arm of chromosome 6, indicating that all three traits were either controlled by the Wx locus or by a genomic region tightly linked to this locus. This finding has provided clues to resolving the molecular bases of GC and GT in future studies. The results also have direct implications for the quality improvement of rice varieties.

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