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1.
Long-acting (LA) preparations of methylphenidate allow for once-daily dosing; however, pharmacokinetics may vary and depend on food intake. The objective was to evaluate effectiveness of a two-phase release formulation (Ritalin® LA) under daily practice conditions. This was a prospective, multicenter, observational study in Germany. Eligibility and dosing were determined by the physician based on the drug label. Outcomes included changes over 3 months of treatment in assessments of effect duration, clinical global impression (CGI), and quality of life (ILK). In 101 sites, 262 patients (197 boys, 63 girls, and two unknown) with a mean age of 10.9 years were enrolled; 50 were treated for the first time; 212 switched medication to Ritalin® LA. After 3 months, CGI improved in 59.4 % of patients, and well-being overall was rated as good by 61.0 % of parents and 63.7 % of children. Based on parents’ assessment, the proportion of children suffering from strong disease burden decreased from 40.7 to 15.1 %. In 123 insufficient responders to previous ADHD medications, benefit from Ritalin® LA was above average and effect duration was significantly prolonged as compared to pretreatment. Overall, 28 patients (10.7 %) had treatment-related adverse events with one case being serious; 23 patients (8.8 %) discontinued therapy, 7 (2.7 %) due to poor treatment response; and 212 patients (81 %) continued treatment beyond the study. In line with clinical trial data, Ritalin® LA provides significant benefit also under routine practice conditions.  相似文献   

2.
The J wave, also known as Osborn wave, is a deflection that can be observed on the surface ECG as a late delta wave, seen at the end of the QRS complex. In this case, a 75-year-old woman, after 1 day of continuous haemodialysis, showed a marked hypothermia (28.5°C) and severe hypokalaemia (1.7 mEq/l). Bradycardia was seen on the monitor and J waves were recognised on the ECG recording. After appropriate replacement of potassium and treatment of hypothermia, the J waves disappeared spontaneously.  相似文献   

3.

Background

With increasing use of cardiac resynchronization therapy (CRT), treating physicians should be familiar with different electrocardiographic (ECG) patterns of left ventricular (LV) lead and biventricular (BiV) pacing. However, there are a few publications on ECG patterns during BiV pacing.

Purpose

This study was sought to determine different ECG patterns in patients with BiV pacing.

Methods

Twelve-lead ECGs during BiV pacing (right ventricular leads at apex and LV leads in one of the lateral coronary veins) were analyzed in 181 consecutive patients (121 male; mean age, 62.0 ± 13.5 years) with advanced heart failure and baseline left bundle branch block pattern after at least 6-month of uncomplicated CRT.

Results

During BiV pacing, 65% of the patients showed a dominant R wave in V1. There was a right axis deviation in 57% in frontal plane. However, a left superior axis emerged in 34% and normal frontal plane axis in 9%. Sequential BiV pacing (73% vs. 58%, P = 0.04) and pacing from posterolateral coronary vein (80% vs. 60%, p = 0.045) were more likely to present with a dominant R wave in V1. In sequential pacing, AV interval was significantly longer in patients with negative complex in V1 than in those with positive complex (124 ± 21 vs. 116 ± 8.0, p = 0.005). A Q/q wave was detected in 85% of patients in lead I and 78% in lead aVL.

Conclusions

BiV pacing from lateral coronary venous branches and right ventricular apex characteristically presented with dominant R wave in V1, Q/q wave in leads I and aVL, and right or left superior axis. However, a negative complex in V1, QRS axis in other quadrants, and lack of Q/q wave in leads I and aVL did not necessarily indicate a problem.  相似文献   

4.
We have studied the influence of NADP+ on routine electrocardiography (ECG) in 6-month-old C57BL/6 and mdx mice. The animals were anesthetized by ether before ECG recording. ECG registration was carried out at a speed of 100 mm/s. The first ECG recording was made before intraperitoneal NADP+ injection in a dose of 13 or 80 mg/kg. The second ECG recording was made 10 min after NADP+ injection. Anesthesia was then terminated. The mice were occasionally anesthetized 45–60 min later, and the third ECG was recorded 1 h after injection of NADP+. ECG recording was carried out at a speed of 100 mm/s in standard leads I, II, and III and unipolar leads AvR, AvL, and AvF. Values of standard ECG characteristics, such as the P wave and the intervals PQ, QT, RR, and the QRS complex, were measured in milliseconds in standard lead II. We did not observe any differences between ECG magnitudes of 2- to 3-month-old C57BL/6 and mdx mice during trial experiments. Mice of both strains had a sinus rhythm in their heart rate. The QRS complex in mdx mice had a tendency to be larger than in C57BL/6 mice. Heart rates fluctuated between 722 ± 22 and 681 ± 21 beats per minute. The effect of NADP+ was studied in 6-month-old male mice. The increase in the RR interval and the decline in heart rate from 697 ± 21 to 461 ± 23 and 491 ± 28 beats per min for C57BL/6 mice (p < 0.01) and from 722 ± 28 beats per minute to 454 ± 31 beats per min for mdx mice were registered 10 min after NADP+ injection at a dose of 80 mg/kg. The increase in the RR interval can be explained by an increase in the QT interval. A statistically significant reduction in the QT interval leading to a diminished RR interval was observed in mdx mice 1 h after NADP+ injection. NADP+ at a dose of 13 mg/kg did not significantly change the ECG properties in mdx mice. ECG of mdx mice was characterized by negative repolarization of the T wave in 37% of all leads. The amount of leads with negative T-wave repolarization decreased up to 3% 1 h after NADP+ injection in dose of 80 mg/kg. The results have shown that cytomembranes of ventricular cardiac myocytes and the degree of oxidative stress are the main targets of the action of NADP+ in C57BL/6 and mdx mouse hearts.  相似文献   

5.
目的:探讨小鼠心肌肥厚发展过程中心电图的动态变化。方法:复制小鼠压力超负荷性心肌肥厚模型,连续动态监测小鼠从心肌肥厚早期至心力衰竭发展过程中的不同阶段体表心电图改变。结果:①对照组和模型组术后2周内小鼠未见自发性心律失常,而模型组术后5周、9周和13周小鼠出现自发性心律失常,主要表现为频发的室性早搏以及阵发性室性心动过速,心律失常发生率分别为15%、28%和63%。②与同期对照相比,术后2周、5周、9周和13周组动物伽间期以及帆间期明显延长,分别延长20.4%、32.7%、49.7%、61.0%和27.1%、32.1%、43.9%、59.1%(P〈0.01)。③心肌肥厚小鼠心电图的另一个特征为J波变化。所有对照组动物心电图均为正向J波,而模型组动物从2周开始J波正向值下降,5周逐渐变平,到13周时完全翻转。④与同期对照相比,模型组的PR间期没有改变,但术后2周RR问期轻微缩短。结论:心肌肥厚小鼠自发性心律失常发生率逐渐增加,QT间期进行性延长,J波幅值逐渐降低,表明随着疾病的进展心室复极化异常逐渐加重。  相似文献   

6.
Although short total sleep time (TST) is associated with increased anxious symptoms in adolescents, it is unknown whether social jetlag, a misalignment between sleep timing on the weekend and school week, is independently associated with anxious symptoms. In the current study, sleep timing, anxious symptoms, and demographic information were assessed from 3097 adolescents (48% female, mean ± SD age 15.59 ± .77 years) from the age 15 wave of the Fragile Families and Child Wellbeing Study. Social jetlag was calculated as the absolute value of the midpoint of sleep on the weekend minus the midpoint of sleep during the school week. Anxious symptoms were measured through the 6-item anxiety subscale of the Brief Symptom Inventory 18. We assessed associations between sleep variables and anxious symptoms using multiple linear regression. Adjusted analyses controlled for sex, race/ethnicity, age in years, body mass index percentile, number of other children below the age of 18 in the household, and primary caregiver (PCG) married/cohabiting with youth’s biological parent, PCG employment status, PCG household income and PCG education level. In fully adjusted models (R2 = .034), school night TST (b = ?.04, ?R2 = .005, p < .001) was negatively associated with anxiety symptoms, while social jetlag (b = .04, ?R2 = .009, p < .001) was positively and independently associated with anxiety symptoms. Findings indicate small associations of school night TST and social jetlag with anxious symptoms. Thus, maintenance of optimal emotional health in adolescents may require both sufficient sleep duration and regularity of sleep timing across the week.  相似文献   

7.
A 48-h microstructure experiment captured the variation of turbulence in Lake Biwa, Japan, during a strong stratification period, 1 week after a typhoon event. A free-fall microstructure profiler (TurboMAP) and a fine-scale profiler (F-probe) were deployed. An array of five ADCPs positioned close to the experiment site provided current measurements associated with the internal-wave field for a period of one week. Strong winds related to the passage of a typhoon close to the lake generated two low-frequency internal waves: a Kelvin wave and an inertial wave. Both waves were in the first baroclinic mode. This study pictures the superposition of two large-scale internal waves and a stronger current resulting from the two waves being in phase. The synchronization of the waves provoked enhanced shear in the hypolimnion, more than 10 m above the bottom, as well as high dissipation (10?7 W kg?1) and vertical diffusivity reaching 10?4 m2 s?1. The enhanced shear event seems to be related to the current amplitude since it occurred when the current amplitude was increased by the diel wind. Assuming the same turbulence intensity for the enhanced hypolimnetic shear events, this superposition may affect nutrient transfer in the hypolimnion. Also, we witnessed sediment resuspension, consisting of high turbidity and high fluorescence intensity, likely due to a combination of bottom stress and enhanced turbulence.  相似文献   

8.
Summarize the value of the change of different parts in treadmill exercise test (TET) ECG to coronary heart disease (CHD) diagnosis. Four hundred and forty-five cases have been included in this investigation, which stayed in our hospital from January of 2006 to March of 2011 and underwent TET and coronary arteriography (CAG). The change of different parts in TET ECG in these patients had been retrospective summarized to determine its diagnosis value to CHD. (1) In the 445 cases of TET testers, 200 cases showed positive in TET with 150 cases of positive CAG, and 50 cases of negative CAG; 245 cases showed negative in TET with 206 cases of negative CAG, and 39 cases of positive CAG. The diagnosis sensitivity of CHD was 79.36 % (150/189), the specificity was 80.47 % (206/256), positive prediction value was 75.00 % (150/200), negative prediction value was 84.08 % (206/245), and false-positive rate was 25.00 % (50/200) with prediction accuracy of 80.00 % (356/445). (2) In the 200 cases with positive TET: 51 cases were in the limb lead group; 73 cases were in the chest lead group; and 76 cases were in the limb lead + chest lead group. There were 150 cases showing positive in CAG: 22 cases were in the limb lead group; 58 cases were in the chest lead group; and 70 cases were in the limb lead + chest lead group. The positive diagnosis rate of ST change in the chest lead was obviously higher than that of simple limb lead group (P < 0.05). (3) People with healthy coronary artery will have decreased amplitude of R wave while patients with coronary stenosis have elevated amplitude of R wave. (4) As for the T wave, the positive CAG had no statistical significance between normal T wave group and TET positive group (P > 0.05); CAG results had statistical significance between normal T wave group and TET negative group (P < 0.05). (5) Positive CAG results had no statistical significance between U-wave inversion group and TET positive group (P > 0.05); positive CAG results has statistical significance when TET negative group compared with U-wave inversion group or TET positive group (P < 0.05). TET is a relatively idea invasive diagnosis method for coronary disease, which can be utilized to evaluate the stage of CHD when integrating with the change of TET ECG.  相似文献   

9.
The aim of the present study was to estimate the endogenous abscisic acid (ABA) content in tulip ‘Apeldoorn’ torpedo and mature somatic embryos. Moreover, the effect of exogenous ABA and/or its inhibitor fluridone on somatic embryo maturation and conversion into plantlets was investigated. Torpedo-stage somatic embryos were subcultured on media containing 5 μM of picloram and 1 μM of 6-benzyl-aminopurine (BAP)—control, and combinations of ABA (0 or 10 μM) and/or fluridone (0 or 30 μM) for 1 week. Then, the torpedo embryos were transferred to a maturation medium containing 0.25 μM of α-naphthaleneacetic acid (NAA) and 2.5 μM of BAP, without ABA and fluridone treatment, and cultivated under darkness or light for ten weeks. Endogenous ABA content (first time measured in tulip somatic embryos) was evaluated by ELISA test. The obtained results revealed that the highest level of endogenous ABA, at 17.45 nmol g?1 dry weight (DW), was recorded in torpedo-stage of tulip embryo development, only after 1 week of ABA treatment, and was nearly 10 times higher in comparison with the control. Simultaneous addition of ABA and fluridone to the medium resulted in the lowering of the ABA concentration to 9.58 nmol g?1 DW. During ten weeks of maturation of the embryos, the endogenous ABA content in mature tissue of tulip somatic embryo considerably decreased to an amount 0.87–1.33 nmol g?1 DW (irrespective of ABA and fluridone treatment) and did not differ significantly from control (0.59 nmol g?1 DW). Exogenous ABA and fluridone significantly decreased the growth value of fresh weight (FW) of the tulip torpedo-shaped and mature embryos under light conditions. Percentage of the DW of the torpedo embryos treated with exogenous ABA was significantly higher (15.43–17.02) in comparison with the control (10.87). Three to three and a half times more malformed mature embryos were noted under light conditions than in darkness, irrespective of ABA and fluridone treatment. The highest percentage of mature embryos forming shoots (conversion) was observed under light conditions in the control and after fluridone treatment (26 and 20%, respectively).  相似文献   

10.
There are controversial reports about cardiac differentiation potential of mesenchymal stem cells (MSCs), and there is still no well-defined protocol for the induction of cardiac differentiation. The effects of retinoic acid (RA) and dimethyl sulfoxide (DMSO) on the proliferation and differentiation of human fetal liver-derived MSCs (HFMSCs) as well as the pluripotent state induced by 5-azacytidine (5-aza) in vitro were investigated. MSCs were isolated from fetal livers and cultured in accordance with previous reports. Cells were plated and were treated for 24 h by the combination of 5-aza, RA and DMSO in different doses. Different culture conditions were tested in our study, including temperature, oxygen content and medium. Three weeks later, cells were harvested for the certification of cardiac differentiation as well as the pluripotency, which indicated by cardiac markers and Oct4. It was found that the cardiac differentiation was only induced when HFMSCs were treated in the following conditions: in high-dose combination (5-aza 50 μM + RA 10?1 μM + DMSO 1 %) in cardiac differentiation medium at 37 °C and 20 % O2. The results of immunohistochemistry and quantitative RT-PCR showed that about 40 % of the cells positively expressed Nkx2.5, desmin and cardiac troponin I, as well as Oct4. No beating cells were observed during the period. The combined treatment with RA, DMSO and 5-aza in high-dose could promote HFMSCs to differentiate into cardiomyocyte-like cells and possibly through the change of their pluripotent state.  相似文献   

11.
Electrocardiographical (ECG) investigations were carried out on 4 and 12 week old WBN/Kob and Wistar male rats. In comparison with Wistar rats which showed ECG findings typical of those of normal rats, WBN/Kob rats showed significantly larger QRS complex amplitude, smaller T wave amplitude, longer QRS duration, and longer QT interval at 4 weeks of age. This tendency became clearer at 12 weeks of age. There were no changes in serum inorganic ion concentrations or cardiac histopathology suggestive of these ECG changes in WBN/Kob rats. These ECG findings in WBN/Kob rats are considered to be a hereditary characteristic of the strain.  相似文献   

12.
To investigate if the 12-lead resting electrocardiogram (ECG) is a predictor of left ventricular (LV) functional recovery after revascularization of chronic total coronary artery occlusions (CTO). Revascularization was performed in 58 CTO patients who had impaired regional wall motion. The 12-lead resting ECG was used to evaluate Q-wave, QT dispersion, and other parameters. Pre- and postoperative LV regional wall motions were evaluated by real-time three-dimensional echocardiography (RT-3DE). In patients with non-Q-wave, the wall motion score index (WMSI) was dropped from 1.56 ± 0.31 to 1.12 ± 0.21 (P < 0.05), while there was no significant changes (1.73 ± 0.12 and 1.59 ± 0.23, P > 0.05) for WMSI in patients with Q-wave. Preoperative non-Q-wave at baseline was predicted recovery with 88 % sensitivity and 68 % specificity. Positive predictive value for recovery was 67 % in patients with non-Q-wave. The presence of Q-wave can predict non-recovery of the regional wall motion with 68 % sensitivity and 88 % specificity. For CTO patients treated by revascularization, recovery can be predicted reliably through the analysis of pathological Q-wave on the 12-lead resting ECG.  相似文献   

13.
14.
In vitro-grown shoot tips of Alnus glutinosa (L.) Gaertn. were successfully cryopreserved by vitrification. Shoot tips (0.5–1 mm) excised from 6-week-old shoots were precultured in hormone-free Woody Plant Medium (WPM) supplemented with 0.2 M sucrose, for 2 days at 4 °C in the dark, and then treated with a mixture of 2 M glycerol plus 0.4 M sucrose, for 20 min at 25 °C. Osmoprotected shoot tips were first dehydrated with 50 % vitrification solution (PVS2), for 30 min at 0 °C, and then placed in 100 % PVS2, for 30 min at 0 °C. The solution was replaced with fresh 100 % PVS2, and the shoot tips were plunged directly into liquid nitrogen. The shoot tips were rewarmed in a water bath at 40 °C for 2 min, and then washed twice, for 10 min at 25 °C, with 1.2 M sucrose solution, before being transferred onto WPM supplemented with 0.5 mg l?1 N 6-benzyladenine, 0.5 mg l?1 indole-3-acetic acid, 0.2 mg l?1 zeatin, 20 g l?1 glucose and 6 g l?1 Difco Bacto agar. The shoot tips were kept in darkness for 1 week and under dim lighting for another week, before being exposed to standard culture conditions (16 h photoperiod). This protocol was successfully applied to three alder genotypes, with recovery rates higher than 50 %.  相似文献   

15.
The present study aimed to evaluate efficacy and adverse effects of Nimotuzumab combined with docetaxel–cisplatin–fluorouracil regimen in the treatment of advanced oral carcinoma. Nine patients with advanced oral carcinoma were treated with Nimotuzumab combined with docetaxel–cisplatin–fluorouracil regimen (test group). The treatment was given as follows: Nimotuzumab 200 mg, given as intravenous infusion once a week for 6 weeks; docetaxel and cisplatin, 75 mg/m2 each, on day 1 only; 5-fluorouracil, 750 mg/m2 infused continually for 8 h, used from day 1 to 5; the total cycle was for 21 days. Another eight patients comprised control group (docetaxel–cisplatin–fluorouracil regimen alone). Study patients from both groups were evaluated for objective response. The response rate was significantly (p = 0.044) higher in test group (88.9 vs. 37.5 % in control group). The disease control rate also tended to be higher in test group (100 vs. 62.5 % in control group; p = 0.083). The major adverse effects were bone marrow suppression, nausea, vomiting, and alopecia. The incidence of adverse effects was similar between both study groups. In conclusion, Nimotuzumab combined with docetaxel–cisplatin–fluorouracil regimen is effective and safe in the treatment of advanced oral carcinoma.  相似文献   

16.
The DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, 1994, American Psychiatric Association) describes attention deficit hyperactivity disorder (ADHD) as a heterogeneous disorder; providing diagnostic criteria for three subtypes: hyperactive/impulsive (ADHD/HI), inattentive (ADHD/I), and combined type (ADHD/C). Differences among the subtypes are well defined, but there may be also differences in terms of treatment responses. The aim of this study is to assess the responses of ADHD/I and ADHD/C to atomoxetine treatment. The medical records of the January–June 2012 term, first time referrals to outpatient clinic, were reviewed, and 37 ADHD diagnosed primary school age children (18 ADHD/I, 19 ADHD/C) that were treated with atomoxetine were determined. Thirty-five of them who completed 8 weeks of treatment duration were recruited for the study. The children with an ADHD medication use history in 2 months time prior to onset of treatment and/or the children receiving additional psychopharmacologic treatment to atomoxetine were excluded. Baseline and eighth week assessment, records were evaluated. Efficacy assessments included Turgay DSM-IV ADHD Screening and Rating Scale parent and teacher forms (T-DSM-IV) and Clinical Global Impression Scale-Severity and Improvement subscales. Safety assessments included laboratory and body weight assessments, ECG, heart rate, and blood pressure evaluations (baseline and eighth week) along a scale filled by the parents at the eighth week to review side effects. Atomoxetine was found to be effective in both ADHD/I and ADHD/C groups. Atomoxetine also decreased the opposition defiance subscale scores of T-DSM-IV (both parent and teacher forms), whereas it was not found to make statistically significant difference in the conduct disorder subscale scores. Mean difference in 8-week time in T-DSM-IV hyperactivity subscale and total scores of parent and teacher forms; inattention subscale scores of only parent forms and the CGI- severity subscale scores; differed significantly among the ADHD/I and ADHD/C groups; that ADHD/C types responded better to medication. Results of this study revealed that atomoxetine is effective both in ADHD/I and ADHD/C subtypes. ADHD/C types may be responding better to atomoxetine treatment than the ADHD/I subtypes.  相似文献   

17.
Despite advances in surgical and reperfusion therapy, there is no effective therapy currently exists to prevent the progressive decline in cardiac function following myocardial infarction. Hepatocyte growth factor has potent angiogenic and anti-apoptotic activities. The aim of this study was to investigate the therapeutic effect and dose–effect relationship on postinfarction heart failure with different doses of adenovirus-mediated human hepatocyte growth factor (Ad5-HGF) transference in swine models. Totally twenty swine were randomly divided into four groups: (a) control group (null- Ad5, 1 ml); (b) low-dose group (1 × 109 Pfu/ml Ad5-HGF, 1 ml); (c) medium-dose group (5 × 109 Pfu/ml Ad5-HGF, 1 ml); (d) high-dose group (1 × 1010 Pfu/ml Ad5-HGF, 1 ml). Four weeks after left anterior descending coronary artery (LAD) ligation, different doses of Ad5-HGF were transferred in three therapeutic groups via right coronary artery. Four and seven weeks after LAD ligation, gate cardiac perfusion imaging was performed to evaluate cardiac perfusion and left ventricular ejection fraction (LVEF). Seven weeks after surgery, the apoptotic index of cardiocyte was observed by TUNEL, the expression of Bcl-2, Bax, α-SMA and Factor VIII in the border zones were evaluated by immunohistochemistry, respectively. Four weeks after myocardial infarction, no significant difference was observed among four groups. Three weeks after Ad5-HGF transfer, the improvement of cardiac perfusion and LVEF was obviously observed, especially after 1 × 1010 Pfu Ad5-HGF transfer. TUNEL assay showed that 5 × 109 Pfu and 1 × 1010 Pfu Ad5-HGF treatment had a obvious reduction in the apoptotic index compared with the null-Ad5 group, especially after 1 × 1010 Pfu Ad5-HGF treatment. The expression of Bcl-2 protein was increased and the expression of Bax protein was inhibited in the 5 × 109 Pfu and 1 × 1010 Pfu Ad5-HGF groups compared with the null-Ad5 group. The vessel density of Factor VIII+ and α-SMA+ was increased in Ad5-HGF groups compared with the null-Ad5 group. There were no significant differences in angiogenesis, reducing apoptosis and ameliorating heart function between the 1 × 109 Pfu Ad5-HGF group and the null-Ad5 group. Although no statistical difference was observed between 1 × 1010 Pfu and 5 × 109 Pfu Ad5-HGF groups, the cardiac protective effects of 1 × 1010 Pfu Ad5-HGF treatment were greater than 5 × 109 Pfu Ad5-HGF treatment. Different doses of Ad5-HGF injected via noninfarct-related artery could induce angiogenesis, reduce apoptosis and ameliorate heart function, and the cardiac protective effects of 1 × 1010 Pfu Ad5-HGF is of most significance.  相似文献   

18.
Heat wave frequency and intensity are predicted to increase. We investigated whether repeated exposure to heat waves would induce acclimation in Quercus rubra seedlings and considered [CO2] as an interacting factor. We measured gas exchange and chlorophyll fluorescence of seedlings grown in 380 (C A) or 700 (C E) μmol CO2 mol?1, and three temperature treatments (ambient, ambient +3 °C, and an ambient +12 °C heat wave every fourth week). Measurements were performed during the third and fourth +12 °C heat waves (July and August 2010) at Whitehall Forest, GA, USA. Additionally, previously unexposed seedlings were subjected to the August heat wave to serve as a control to determine acclimation of seedlings which were previously exposed. Seedlings with a history of heat wave exposure showed lower net photosynthesis (A net) and stomatal conductance (on average ?47 and ?38 %, respectively) than seedlings with no such history, when both were subjected to the same +12 °C heat wave. During both heat waves, A net significantly declined in the +12 °C treatment compared with the other treatments. Additionally, the A net decline during the August compared with the July heat wave was stronger in C E than in C A, suggesting that elevated [CO2] might have had a negative effect on acclimation capacity. We conclude that seedlings subjected to consecutive heat waves will moderate stomatal conductance outside the heat wave, to reduce water usage at lower temperatures, increasing survival at the expense of carbon assimilation.  相似文献   

19.
The study aimed at defining reference values for electrocardiographic (ECG) and echocardiographic parameters as well as macroscopic dimensions of the heart and microscopic dimensions of cardiomyocytes in the European brown hare. The studies were conducted on 30 adult, clinically healthy hares of either sex caught in Poland. ECG and echocardiography were performed supravitally on anaesthetized hares. After euthanasia, gross and microscopic myocardial and cardiomyocyte dimensions were determined. Heart rate amounted to 140 ± 37.5 beats/min, the leading rhythm involved the sinus rhythm. P wave time was 26 ± 5 ms, PQ time was 80 ms, QRS time was 29 ± 3.5 ms, and ST was 97.5 ± 7 ms. Echocardiography determined a left ventricular wall end-diastolic diameter of 8.6 ± 2.0 mm and an intraventricular septum end-diastolic diameter of 5.75 ± 1.0 mm. The thickness of the interventricular septum corresponded to that of the free wall of the left ventricle, a finding consistent with physiological hypertrophy. Preliminary reference values were established for echocardiography. The findings were similar to those obtained at necropsy. The ECG and echocardiographic studies represent the first supravital examination of cardiac function in the hare. The obtained results illustrate adaptation of hare's myocardium to its mode of life. The cardiac findings resemble the athlete's heart syndrome described in humans. The findings may prove useful in further studies on the physiology of the cardio-vascular system in the hare.  相似文献   

20.
The present study was designed to evaluate the hepatoprotective potential of α-lactalbumin (αLA) against dimethylnitrosamine (DMN)-induced toxic insults in the rat liver. The liver damage was induced in rats by the repeated administration of DMN (10 mg/kg, i.p.) on three consecutive days per week for three weeks. The rats were maintained on either a standard AIN-93 M or αLA-enriched diet starting one week before the DMN injection until the termination of the experiment. The DMN treatment produced a progressive increase in the plasma markers (aspartate aminotransferase, alanine aminotransferase, total bililbin, hyarulonic acid, and matrix metalloproteinase-2) in 28 days after the first DMN injection. Dietary treatment with αLA significantly reduced the DMN-induced damage toward normalcy. N-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, significantly attenuated the hepatoprotective effect of αLA. These findings show that αLA has a marked suppressive effect on hepetic fibrosis through a nitric oxide-mediated mechanism.  相似文献   

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