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1.
World J Clin Cases ; 12(12): 2086-2091, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38680270

RESUMO

BACKGROUND: Venous variations are uncommon and usually hard to identify, and basilic vein variation is particularly rare. Basilic vein variation usually presents without any clinical symptoms and is often regarded as a benign alteration. This case was a patient with congenital basilic vein variation encountered during surgery for an infusion port. CASE SUMMARY: We documented and analyzed an uncommon anatomical variation in the basilic vein encountered during arm port insertion. This peculiarity has hitherto remained undescribed in the literature. We offer remedial strategies for addressing this anomaly in the future and precautionary measures to circumvent its occurrence. We conducted a comprehensive review of analogous cases in the literature, offering pertinent therapeutic recommendations and solutions, with the aim of enhancing the efficacy and safety of future arm port implantations. CONCLUSION: Venous variation is rare and requires detailed intraoperative and postoperative examination to ensure accuracy, so as not to affect subsequent treatment.

2.
Ying Yong Sheng Tai Xue Bao ; 26(8): 2405-13, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26685604

RESUMO

Surveying data for wind lodging disaster happening in Nanyang of Henan Province in August 1, 2013, were used to analyze the effects of strong wind lodging at pre- and post-tasseling stages on growth and yield of summer maize, and to determine the differences in lodging resistance among varieties and the suitable sowing time for summer maize. The survey included two varieties of summer maize, Xundan 20 and Zhengdan 958, with five and three sowing dates, respectively. The lodging was divided into four types, i.e., root slope ( RS) , root lodging ( RL) , stem bending (SB) and stem broken (SBK). The results showed that wind lodging occurring at pre- and post-tasseling stages resulted in high lodging percentages for both varieties and all sowing dates. The lodging percentage of Xundan 20 variety ranged between 86.0% and 98.5% for five sowing dates. For Zhengdan 958 variety, it ranged between 60.0% and 76.4% for three sowing dates. After tasseling, the earlier the sowing date, the lower the lodging rate occurred. The main lodging types happening around the tasseling stage were RL with the lodging rate of 53.0%-84.3% for sowing dates II-V of Xundan 20. The main lodging type for sowing date I was SB with the lodging rate of 37.5%. Lodging reduced the aboveground dry matter with the greatest reduction rate occurring in SB, followed by RS and RL. Lodging increased the allocation of dry matter to leaves and stems, but decreased the allocation to spikes. RL and SB shortened the length and diameter of spike, and reduced the grain number per spike. The lodging occurring after the tasseling stage also reduced 100-grain mass. RS had no significant effects on spike characters and yield components. The lodging had serious effects on the yield of summer maize. The yield loss was highest for SB with the reduction percentages of 74.2% and 68.7% for Xundan 20 and Zhengdan 958, respectively. SB occurring before the tasseling stage would lead to a complete crop failure. RL decreased the average yield by 46.3% and 46.5% for Xundan 20 and Zhengdan 958, respectively. RS decreased the averaged yield by 8.4% and 13.2% for Xundan 20 and Zhengdan 958, respectively. The mean yields of Xundan 20 and Zhengdan 958 were 4959.9 and 6026.1 kg · hm(-2) after the wind lodging, respectively. The later the sowing date, the higher the yield loss rate was observed for Xundan 20, however, there were no significant difference in yield loss among different sowing dates of Zhengdan 958. In general, Zhengdan 958 had stronger lodging resistance than Xundan 20.


Assuntos
Vento , Zea mays/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento
3.
Huan Jing Ke Xue ; 32(10): 3023-32, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22279919

RESUMO

Experiments were conducted under open-top-chambers conditions to assess the photosynthetic responses of wheat plants (Triticum aestivum L., YangMail6) to supplemental UV-B radiation (10%-10.9% higher then control group, T1) and enhanced ozone [(100 +/- 9) nmol x mol(-1), T2], separately and in combination (combination treatment, T3), making use of LCpro + Portable Photosynthesis System and DIVING-PAM Fluorometer to determine gas exchange and chlorophyll fluorescence parameters. Results indicated that P(n), G(s), T(r), P(m) and I(k) of T1, T2 and T3 treatments decreased significantly compared to CK (control group, natural air and UV-B radiant intensity condition), while there were no differences between T3 and T1 or T2 or both in major growth stages. UV-B fiercely inhibited the stomatal conductance and transpiration of plants, while T1 stimulated stomata opening and transpiration in jointing stage. Dark respiration (R(d)) of T1 was increased, while no significance difference was found between T2 and CK or T3 and CK in most stages. T1 and T2 reduced F(v)/F(m) value only in booting stage, while T3 was significant lower than CK except jointing stage. qP value declined significantly in treatments of T1, T2 and T3 as Compared to CK, with decreasing amplitude occurring in the order T3 > T1 > T2. NPQ, Y (NPQ), Y (NO) value of T1, T2 and T3 treatments increased significantly compared to CK, with maximum increasing amplitude occurring in the order T3 > T1 > T2, of which NPQ of T1 and T2 turned to decrease since filling stage, and T3 turned to decrease since flowering stage to a greater degree than T1 and T2. T1, T2 and T3 also caused significance reduction in Y (II), with reducing amplitude occurring in the order T3 > T1 > T2. Obviously, supplemental UV-B radiation and enhanced ozone caused a significant decrease in gas exchange capacity, maximum photochemical capacity and photosynthetic activity of winter wheat, and the photoprotective mechanism was damage, leading to greater proportion of excitation energy dissipated in the form of non-regulated heat and fluorescence. The photosystems of winter wheat were damaged by both excess energy and UV-B or excess energy and O3, or excess energy, UV-B and O3 together. UV-B and O3 in combination enhanced the negative effects on photo-protective mechanisms and excitation energy distribution in PS II compared to UV-B or O3 alone, while the interactive effects were less than addition.


Assuntos
Ozônio/farmacologia , Fotossíntese/fisiologia , Estresse Fisiológico/fisiologia , Triticum/fisiologia , Raios Ultravioleta , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Estações do Ano
4.
Huan Jing Ke Xue ; 31(7): 1643-51, 2010 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-20825039

RESUMO

Stress effects of surface increased ozone concentration on winter wheat photosynthesis, lipid peroxidation and antioxidant systems in varied growth stages (jointing stage, booting stage, blooming stage and grain filling stage) were studied, the winter wheat was exposed to open top chambers (OTCs) in an open field conditions to three levels ozone concentrations (CK, 100 nmol x mol(-1), 150 nmol x mol(-1)). The results revealed that within 150 nmol x mol(-1) ozone concentration, as the ozone concentration and time increased,total chlorophyll content,chlorophyll a and b contents of winter wheat leaves were general declined,but compared to CK, the total chlorophyll and chlorophyll a content of T1 treatment groups were a little higher at booting and blooming stage; the conductance of stomatal was affected, the activation of unit leaf area decreased, intercellular CO2 concentration and stomatal limitation value showed a fluctuation change tendency. At the same time, a self-protective mechanism of winter wheat were launched. Concrete expression of SOD activity first increased rapidly and then gradually decreased, the activity of POD showed a decrease firstly and then rapidly increased. From the jointing stage to the blooming stage and from the grain filling stage one to grain filling stage two, the activity of CAT rapidly increased first and then comparatively decreased, but the content of MDA kept steadily rising. The carotenoid content increased first and then decreased, heat dissipation of unit leaf area increased. These results indicate that antioxidant enzymes can not completely eliminate excessive reactive oxygen species in vivo of winter wheat, then lead to accumulation of reactive oxygen species, further exacerbate the lipid peroxidation, that result in the increase of membrane permeability, degradation of chlorophyll, reduction of net photosynthetic rate, imposing on the winter wheat leaves senescence process.


Assuntos
Antioxidantes/metabolismo , Ozônio/toxicidade , Fotossíntese/fisiologia , Triticum/fisiologia , Peroxidação de Lipídeos , Peroxidase/metabolismo , Estações do Ano , Estresse Fisiológico , Superóxido Dismutase/metabolismo , Triticum/metabolismo
5.
Huan Jing Ke Xue ; 31(2): 472-9, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20391720

RESUMO

In order to provide basis for evaluating the effects of air pollutant such as O3 on crops yield and food security, the effects of O3 fumigation (ambient air, CK; 100 nL x L(-1), T1; 150 nL x L(-1), T2) on chlorophyll a fluorescence and gas exchange of a field-grown winter-wheat (Triticum aestivum L. Yang Mai 13) in different growing period were conducted via open-top chamber technique in conjunction with Diving-PAM fluorometer and LC pro + photosynthesis system. Results indicated that Fv/Fm caused by T1 was higher than 0.8, while the Pm, qP, (1-qP)/NPQ and Y(NO) were similar to those of CK, the NPQ and Y(NPQ) were increased by 13.5%-29.0% and 13.3%-22.7% respectively due to O3 stress. Under nature light (rapid light curve, RLC) and after dark adaptation (induction curve in steady-state, IC) the Yield of T1 was decreased by 4.6%-7.6% and 11.3%-19.3% respectively, with 8.0%-9.8% and 11.0%-23.1% reductions in Pn, and Gs compared to CK, respectively. In heading stage and blooming stage, the Ls of T, was greater than CK, but in filling stage and mature stage, it became lower compared to CK. The Fv/Fm was slightly lower than 0.8 under T2 treatment, with the Y(NO), (1-qP)/NPQ and c(i) were increased by 37.9%-75.6%, 157.1%-325.8% and 3.4%-18.1% relative to CK. Under RLC and IC condition, the Yield of T2 was respectively decreased by 10.2%-13.6% and 21.4%-29.1%, and the Pn, Ls, qP, Pm, NPQ and Y(NPQ) were decreased by 28.1%-39.9%, 5.2%-21.3%, 15.8%-30.4%, 27.6%-45.6%, 3.3%-52.9% and 5.7%-17.9% in comparison, respectively. Obviously the enhanced O3 causes a significant decrease in the capacity of photosynthesis of winter wheat, and the influence mechanism presents a series of dynamic changes according to growing seasons. The reduction of Fv/Fm under T1 treatment is a response of PS II reaction center to the increase of NPQ, and the decrease in Pn and Yield is a consequence of protective adjustment, by this approach, the antioxidant system and energy dissipation mechanism can thus prevent light damage to the PS II reaction center of winter wheat. Under T2 treatment, the CO2 assimilation and Q(A) re-oxidizing during actinic illumination are restricted, the energy dissipation mechanism was destroyed, and the reduction of photosynthesis was mainly due to damage in photosystem caused by O3 and excess light. The critical loads for O3 of PS II reaction center is between 100 nL x L(-1) and 150 nL x L(-1) close to 100 nL x L(-1). While the Fv/Fm value is not an effective index for assessing O3 influence on winter-wheat. Although the winter-wheat can have certain adapted ability to O3 stress, the growing enhancement of surface O3 is still a great threat to agricultural production in China.


Assuntos
Poluentes Atmosféricos/toxicidade , Clorofila/análise , Ozônio/toxicidade , Fotossíntese/fisiologia , Triticum/fisiologia , Dióxido de Carbono/metabolismo , Clorofila A , Fluorescência , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Estresse Fisiológico , Triticum/efeitos dos fármacos
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