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1.
Toxocariasis is a soil-transmitted helminthozoonosis due to infection of humans by larvae of Toxocara canis. The disease could produce cognitive and behavioral disturbances especially in children. Meanwhile, in our modern era, the incidence of immunosuppression has been progressively increasing due to increased incidence of malignancy as well as increased use of immunosuppressive agents. The present study aimed at comparing some of the pathological and immunological alterations in the brain of normal and immunosuppressed mice experimentally infected with T. canis. Therefore, 180 Swiss albino mice were divided into 4 groups including normal (control) group, immunocompetent T. canis-infected group, immunosuppressed group (control), and immunosuppressed infected group. Infected mice were subjected to larval counts in the brain, and the brains from all mice were assessed for histopathological changes, astrogliosis, and IL-5 mRNA expression levels in brain tissues. The results showed that under immunosuppression, there were significant increase in brain larval counts, significant enhancement of reactive gliosis, and significant reduction in IL-5 mRNA expression. All these changes were maximal in the chronic stage of infection. In conclusion, the immunopathological alterations in the brains of infected animals were progressive over time, and were exaggerated under the effect of immunosuppression as did the intensity of cerebral infection.  相似文献   
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Levels of free and bound polyamines (PAs) have been analysedin different organs of diploid, haploid and hypohaploid phenotypesof Nicotiana plumbaginifolia. In leaves and stems there is apositive correlation between the content of the PAs bound tomacromolecules and ploidy level. In contrast, in flowers a negativecorrelation is found with bound spermidine (Spd) levels. Besidesthe ploidy degree, the high levels of Spd in the flowers ofthe haploid and hypohaploid phenotypes might be also due tothe abnormal floral development and thus supports the view thatthis triamine could play a role in floral differentiation. (Received January 16, 1990; Accepted June 6, 1990)  相似文献   
4.
Previous work revealed that Harmonia axyridisPallas (Coleoptera: Coccinellidae) in Beijing, China, were capable of regenerating a forelimb amputated in the fourth instar; 75% of surviving individuals fully regenerated the limb during pupation. In this study, we tested a population of H. axyridis invasive in North America and found that virtually 100% of beetles surviving the operation successfully regenerated the limb. Ablated/regenerated beetles spent longer in pupation, and emerging females were smaller than controls. However, reproductive success was unaffected in all pairwise crosses of control/regenerated adults; there were no differences in pre‐oviposition period, the time required to produce 10 clutches, 10‐day fecundity, or the fertility of eggs, whereas ablated/regenerated parents paid a developmental cost, their progeny obtained benefits. Offspring of crosses that included a regenerated parent tended to have faster larval development than the control cross, although not all were significantly different from controls. However, when either or both parents were ablated and regenerated, their daughters were heavier than controls at emergence. Limb regeneration during pupation appears to activate a physiological cascade which increases the magnitude of beneficial parental effects normally conferred to progeny, possibly via pleiotropic effects. The invasive North American H. axyridis population appears to have higher regeneration capacity than the Chinese population tested previously, although how regeneration capacity might be associated with invasiveness remains unclear. Limb regeneration ability may be a side effect of selection on other traits that confer high fitness under either natural or sexual selection, as it seems unlikely to confer fitness benefits directly in this species.  相似文献   
5.
Direct somatic embryos were differentiated on cotyledon transverse Thin Cell Layers (tTCLs) of Panax ginseng after 9 weeks in the Murashige and Skoog basal (MS) medium containing 2,4-d (5M). When MS medium containing 2,4-d (5M) was used for seedling pretreatment and for tTCLs culture, somatic embryos were observed 2 weeks earlier, i.e. after 7 weeks of culture. On the tTCLs from seedlings pretreated with 2,4-d (5M) combined with benzyladenine and zeatin at 0.1 M (BZ), somatic embryos were observed after 6 weeks of culture and the percentage of embryogenesis was higher (62%) than when 2,4-d was used alone for pretreatment (40%). Similar results were also obtained from pretreatment with combinations of 2,4-d (5M) and thidiazuron (TDZ) (0.01, 0.1M). When a combination of 2,4-d (5M) and BZ (0.1M) was used both for seedling pretreatment and for tTCLs culture, both somatic embryos and shoots were observed after only 3 weeks. As the concentration of BZ increased, the percentage of somatic embryogenesis decreased but the percentage of organogenesis increased. Similar responses were obtained with a combination of 2,4-d (5M) and TDZ (0.01M). On the medium containing both NAA (0.3M) and BZ (1M), globular- and heart- stage embryos developed after 4 weeks of culture into cotyledonary-staged embryos which remained dormant after a short elongation of the embryo axis. The importance of seedling pretreatment by growth substances in enhancing somatic embryogenesis is reported.Abbreviations BA 6-benzyladenine - BZ combination of BA and zeatin - 2,4-d 2,4-dichlorophenoxyacetic acid - MS medium Murashige and Skoog basal medium - NAA a-naphthaleneacetic acid - TDZ thidiazuron - tTCLs transverse thin cell layers - TCL longitudinal thin cell layer  相似文献   
6.
The study aims to investigate the effect of foliar spray with three plant growth regulators (PGRs) p-Chlorophenoxyacetic acid (CPA) at 20 and 40 ppm; Gibberellic acid (GA3) at 20 and 30 ppm, 1-Naphthaleneacetic acid (NAA) at 10 and 20 ppm on the response of fruit set, yield, and fruit quality of some hot pepper cultivars (Chillina, Parbirian, Shampion, and Hyffa) grown in sandy soil under plastic tunnels as compared to the control. Spraying Chillina cultivar GA3 at 30 ppm significantly increased the number of fruits/ plant and fruit set (%), yield/plant, and total yield/fad. In addition, the contents of TSS and Vit C, furthermore, maximum capsaicin content were observed in chili fruits in both seasons. However, the interaction between Chillina cultivar and spraying with GA3 at 20 ppm ranked second in yield and quality. The interaction between Parbirian cultivars and spraying with GA3 at 20 or 30 ppm increased the number of flowers/plants in both seasons. On the other hand, the interaction between Shampion cultivar and spraying with tap water (control) gave the lowest values of the number of flowers/ plants, the number of fruits/ plant and fruit set (%), yield, and its components, and fruit quality in both seasons.  相似文献   
7.
This study represents an efficient preliminary protocol for in vitro mass production of two Paulownia species (Paulownia hybrid and Paulownia tomentosa) seedlings by using seed explant. Different concentrations of benzyladenine (BA) or Kinetin (Kin) (0.0, 2.0, 4.0, 6.0, 8.0 and 10.0 mg/L) were tested during multiplication stage. The number of shoots/explants was significantly increased with increasing either BA or Kin concentration; however, the shoot length significantly decreased. Data show that media fortified by BA (10 mg/L) combined with indole butyric acid (IBA) at 1.0 or 1.5 mg/L recorded the highest number of shoots/explant (9.13 and 9.25, respectively). After six weeks during the multiplication stage, data cleared that media fortified by benzyladenine (10 mg/L) combined with IBA at 0.5 mg/L recorded the highest shoot length (3.23 cm). The inclusion of indole butyric acid (IBA) or naphthalene acetic acid (NAA) at 1.0–1.5 mg/L to the medium significantly increased the number of roots/plantlets and the highest root length. The results indicated that IBA supplementation was more effective than NAA for in vitro rooting of both Paulownia species. The best treatment for multiplication was 10 mg/L and 8.0–10 mg/L BA for P. hybrid and P. tomentosa, respectively. Peat moss and sand (1:1, v/v) or peat moss and sand (1:2, v/v) were investigated as soil mixture during the adaptation stage. The results referred that Paulownia species plantlets were successfully survived (100 %) in soil mixture contained peat moss: sand (1:2, v/v). This mixture recorded the highest values of plantlet height and number of leaves/plantlets.  相似文献   
8.
A greenhouse experiment was conducted to study the effects of four irrigation intervals (4, 8, 12, and 16 days) and six harvests (2, 4, 6, 8, 10, and 12 months after transplanting) on biomass, essential oil content, and composition of Plectranthus amboinicus (Lour .) Spreng . Fresh weight and essential oil yield decreased with increasing irrigation interval; whereas, essential oil content was stimulated by water stress and increased as the irrigation interval increased. Fresh weight of Plectranthus amboinicus irrigated every 4 days peaked when harvested at 6 months, but essential oil content peaked when irrigated every 16 days and harvested at 2 months after transplantation. On the other hand, essential oil yield peaked when irrigated every 8 days and harvested at 6 months. Thymol, p‐cymene, γ‐terpinene, and β‐caryophyllene were the major compounds, and they peaked at different irrigation intervals and harvest times. This study showed biomass, essential oil content, and yield as well as the major and minor constituents of Plectranthus amboinicus are influenced by irrigation interval and the timing of harvest.  相似文献   
9.
Summary Callus induction, somatic embryogenesis and plant regeneration were obtained in two cultivars of Sorghum bicolor (L.) Moench. Transverse thin cell layers from roots/epicotyls of 15-day-old seedlings or of regenerated plantlets were used. Callus response depended on the genotype, the size of transverse thin cell layers, the level at which transverse thin cell layers were excised on the epicotyl, the composition of growth substances and the number of in vitro regeneration cycles undergone by the donor plant. Somatic embryos were differentiated under a defined dark/light sequence, from epidermised compact calluses (i.e having already differentiated an epidermis), obtained directly with dicamba or from friable callus initiated with kinetin and 2,4 dichlorophenoxyacetic acid. The importance of kinetin and dicamba on the induction of embryogenic potential is reported.Abbreviations 2,4-D 2,4 dichlorophenoxyacetic acid - 2iP N6-(2-isopentyl)adenine - BAP 6-benzylaminopurine - CaMV cauliflower mosaïc virus - CPPU N-(2-chloro 4-pyridyl)-N-phenylurea - dicamba 3,6-dichloro-o-anisic acid - IAA indole-3-acetic acid - K kinetin - MS Murashige and Skoog - NAA -naphthaleneacetic acid - PEPC phosphoenolpyruvate carboxylase - SD standard deviation - tTCL transverse thin cell layer  相似文献   
10.
Douris, PC, Handrakis, JP, Gendy, J, Salama, M, Kwon, D, Brooks, R, Salama, N, and Southard, V. Fatiguing upper body aerobic exercise impairs balance. J Strength Cond Res 25(12): 3299-3305, 2011-There are many studies that have examined the effects of selectively fatiguing lower extremity muscle groups with various protocols, and they have all shown to impair balance. There is limited research regarding the effect of fatiguing upper extremity exercise on balance. Muscle fiber-type recruitment patterns may be responsible for the difference between balance impairments because of fatiguing aerobic and anaerobic exercise. The purpose of our study was to investigate the effect that aerobic vs. anaerobic fatigue, upper vs. lower body fatigue will have on balance, and if so, which combination will affect balance to a greater degree. Fourteen healthy subjects, 7 men and 7 women (mean age 23.5 ± 1.7 years) took part in this study. Their mean body mass index was 23.6 ± 3.2. The study used a repeated-measures design. The effect on balance was documented after the 4 fatiguing conditions: aerobic lower body (ALB), aerobic upper body (AUB), anaerobic lower body, anaerobic upper body (WUB). The aerobic conditions used an incremental protocol performed to fatigue, and the anaerobic used the Wingate protocol. Balance was measured as a single-leg stance stability score using the Biodex Balance System. A stability score for each subject was recorded immediately after each of the 4 conditions. A repeated-measures analysis of variance with the pretest score as a covariate was used to analyze the effects of the 4 fatiguing conditions on balance. There were significant differences between the 4 conditions (p = 0.001). Post hoc analysis revealed that there were significant differences between the AUB, mean score 4.98 ± 1.83, and the WUB, mean score 4.09 ± 1.42 (p = 0.014) and between AUB and ALB mean scores 4.33 ± 1.40 (p = 0.029). Normative data for single-leg stability testing for this age group are 3.9 ± 1.9. Higher scores reflect greater balance deficits. The AUB condition produced the greatest balance deficit. Our data provide evidence of the important role of the upper body in maintaining unilateral standing balance and supports its inclusion as part of rehabilitation and training protocols designed to improve balance.  相似文献   
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