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Taking the detached leaves of tree peony (Paeonia suffruticosa cv. 'Roufurong') as test materials, this paper studied the effects of high temperature (40 °C) and low temperature (15 °C) stresses on the PS II functions and physiological characteristics of peony leaves under strong light in tensity (1400 μmol·m-2·s-1), with 25 °C as the control. With the increasing time of highand low temperature stress, the maximal photochemical efficiency (Fv / Fm ), actual quantum yield of photosystem II(ΦPS II), and efficiency of excitation capture of open PS II center (Fv′/ Fm′) all decreased continuously. After recovered in the dark for 4 hours, the Fv / Fm in treatments 15 °C and 25 °C quickly recovered, but that in treatment 40 °C only recovered to 75. 5% of nontreatment, even if the leaves were treated in the dark for 15 hours. At 40 °C, the balance of excited energy be tween PS I and PS II under strong light intensity was perturbed seriously. Treatment 40 °C inhibited the superoxide dismutase (SOD) activity, enhanced the production of O2-.-, H2O2, and MDA, and reduced the contents of chlorophyll and soluble protein. This study revealed that strong light combined with high temperature impaired the photosynthetic apparatus of the tree peony irreversibly, whereas strong light plus low temperature had weaker impact. [ABSTRACT FROM AUTHOR]

Objective: To study the changes in the activities of carbon monoxide (CO) and heme oxygenase 2 (HO-2) in ED rats with hyperhomocysteinemia (HHcy)., Methods: This study included 40 male Wistar rats weighing 280 - 310 g, 10 as normal controls (group A). HHcy models were made in the other 30 by giving 3% methionine for 4 weeks, and then divided into groups B, C and D. The rats in group B continued to be fed with 3% methionine, those in group C were treated with betaine hydrochloride, and those in group D were given zinc porphyrin IX at 45 micromol per kg per d. Penile erections of the rats were recorded, and 4 weeks later, all were killed for determination of the levels of homocysteine (Hcy) in the blood plasma and the activities of CO and HO-2 in the corpus cavernosum of the penis., Results: The level of plasma Hcy, penile erection frequency and the content of CO in the corpus cavernosum were (12.55 +/- 0.82) micromol/L, (1.88 +/- 0.05) times and (10.55 +/- 1.73) micromol/L in group A, the Hcy level significantly higher while the penile erection frequency and CO content remarkably lower than in group B ([25.01 +/- 0.94] micromol/L, [0.70 +/- 0.05] times and [9.51 +/- 1.52] micromol/L, P < 0.05 or P < 0.01), with a negative correlation between the level of Hcy and that of CO and HO-2 (P < 0.01). Compared with group B, the three parameters were all significantly increased in C ([14.37 +/- 0.47] micromol/L, [1.18 +/- 0.08] times and [10.36 +/- 1.56] micromol/L, all P < 0.05 or P < 0.01)., Conclusion: Decreased expressions of CO and HO-2 in the corpus cavernosum of the penis may result in ED in HHcy rats. Betaine can reduce the Hcy level in the blood plasma and CO content in the corpus cavernosum, which might be one of the mechanisms of its action on ED with HHcy.

Taking the detached leaves of tree peony (Paeonia suffruticosa cv. 'Roufurong') as test materials, this paper studied the effects of high temperature (40 degrees C) and low temperature (15 degrees C) stresses on the PS II functions and physiological characteristics of peony leaves under strong light intensity (1400 micromol x m(-2) x s(-1)), with 25 degrees C as the control. With the increasing time of high- and low temperature stress, the maximal photochemical efficiency (Fv/Fm), actual quantum yield of photosystem II (Phi(PS II)) , and efficiency of excitation capture of open PS II center (Fv'/Fm') all decreased continuously. After recovered in the dark for 4 hours, the Fv/Fm in treatments 15 degrees C and 25 degrees C quickly recovered, but that in treatment 40 degrees C only recovered to 75.5% of non-treatment, even if the leaves were treated in the dark for 15 hours. At 40 degrees C, the balance of excited energy between PS I and PS II under strong light intensity was perturbed seriously. Treatment 40 degrees C inhibited the superoxide dismutase (SOD) activity, enhanced the production of O2-, H2O2, and MDA, and reduced the contents of chlorophyll and soluble protein. This study revealed that strong light combined with high temperature impaired the photosynthetic apparatus of the tree peony irreversibly, whereas strong light plus low temperature had weaker impact.

Objective: To analysis the economic burden of varicella inpatient in China, 2007., Methods: In three provinces, the sample places stratified by economic status in district, county and township level and were selected. 185 varicella inpatients were sampled and analysized., Results: The cost of inpatient was 4025.86 RMB per case, including RMB 2952.6 direct cost and RMB 1073.26 indirect cost per case. The total cost of varicella inpatient in China was RMB 103 million in 2007., Conclusion: The disease burden is heavy in China.