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821.
Diurnal changes in gas exchange and chlorophyll fluorescence were measured in the top canopy leaves of the tropical rainforest tree species, Macaranga conifera (Zoll.) Muell. Arg. during a drought year. Maximum values of net photosynthetic rate (P(n), 10 &mgr;mol m(-2) s(-1)) and stomatal conductance (g(s), 0.2 mol m(-2) s(-1)) were found in east-facing leaves in early morning. After 1000 h, both P(n) and g(s) decreased. Minimum daytime values of P(n), g(s), and photosystem II (PSII) quantum yield (DeltaF/F(m)') were found in horizontally fixed leaves. At a given electron transport rate through PSII (ETR), P(n) was higher in early morning than at midday, suggesting a high rate of photorespiration at midday. We tested the hypothesis that the effect of low leaf temperature (T(leaf)) on P(n) is significant in the early morning, whereas the effect of low g(s) on P(n) predominates at midday. In the early morning, when T(leaf) was increased from 32 to 38 degrees C by artificial heating, P(n) at a given ETR decreased 29%, suggesting that the low T(leaf) was associated with a high P(n). When T(leaf) at midday was decreased from 37 to 32 degrees C by artificial cooling, P(n) increased 22%, but P(n) at a given ETR was higher in early morning than at midday, even at the same low T(leaf) (32 degrees C). This suggests that the rate of photorespiration was higher at midday than in early morning because low g(s) at midday caused a reduction in leaf intercellular CO(2) concentration. We conclude that low P(n) at midday was the result of both a reduction in the photochemical process and an increase in stomatal limitation. 相似文献
822.
Takeshi Watanabe Atsuhiko Kato Hiromichi Terashima Koichi Matsubara Yu Jau Chen Kenji Adachi Hideaki Mizuno Masami Suzuki 《Journal of toxicologic pathology》2015,28(1):43-49
Recently, large-scale gene expression profiling is often performed using RNA extracted from unfixed frozen or formalin-fixed paraffin embedded (FFPE) samples. However, both types of samples have drawbacks in terms of the morphological preservation and RNA quality. In the present study, we investigated 30 human prostate tissues using the PFA-AMeX method (fixation using paraformaldehyde (PFA) followed by embedding in paraffin by AMeX) with a DNA microarray combined with laser-capture microdissection. Morphologically, in contrast to the case of atypical adenomatous hyperplasia, loss of basal cells in prostate adenocarcinomas was as obvious in PFA-AMeX samples as in FFPE samples. As for quality, the loss of rRNA peaks 18S and 28S on the capillary electropherograms from both FFPE and PFA-AMeX samples showed that the RNA was degraded equally during processing. However, qRT-PCR with 3’ and 5’ primer sets designed against human beta-actin revealed that, although RNA degradation occurred in both methods, it occurred more mildly in the PFA-AMeX samples. In conclusion, the PFA-AMeX method is good with respect to morphology and RNA quality, which makes it a promising tool for DNA microarrays combined with laser-capture microdissection, and if the appropriate RNA quality criteria are used, the capture of credible GeneChip data is well over 80% efficient, at least in human prostate specimens. 相似文献
823.
Rui KANO Tomoko TAKAHASHI Takeshi HAYAKAWA Yoshiki YAMAYA Atsuhiko HASEGAWA Hiroshi KAMATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1183-1185
Feline upper respiratory tract infection due to Aspergillus spp. is
considered an emerging disease, with the number of reported cases continuing to rise. In
this study, we report the first case of feline sinonasal aspergillosis caused by
Aspergillus fischeri in Japan. The patient presented after 2 months of
progressive facial deformity around the nose and nasal discharge. The isolate from this
case was susceptible to itraconazole (ITZ), voriconazole and micafungin, but was resistant
to amphotericine B. However, the infected cat died approximately 1 month after referral,
despite treatment for 12 days ITZ administered orally at 10 mg/kg. 相似文献
824.
Konosuke OTOMARU Takuro FUJIKAWA Yasuo SAITO Takaaki ANDO Takeshi OBI Naoki MIURA Chikara KUBOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1191-1193
A 10-month-old Japanese black heifer was diagnosed as having an intra-abdominal
cyst using computed tomography (CT). Through a posterior ventral midline incision, the
cyst was removed, and the heifer completely recovered after the surgery. CT scans enabled
detection of the intra-abdominal cyst and measurements of the diameter of the cyst before
the surgery. 相似文献
825.
Mohamed Elshabrawy GHANEM Erisa TEZUKA Bhuminand DEVKOTA Yoshiaki IZAIKE Takeshi OSAWA 《The Journal of reproduction and development》2015,61(1):54-60
We investigated the relationship between the persistence of uterine bacterial infections with cytologically determined endometritis and ovarian function in 65 postpartum Holstein cows. Vaginal mucus discharges were collected, and endometrial smear samples (n = 130) were collected for cytological and bacteriological examinations from the cows at weeks 5 and 7 postpartum (pp). Blood samples were collected at weeks 3, 5 and 7 pp to determine plasma progesterone concentrations to monitor ovarian activity. According to the bacteriological examination, cows were classified into four groups. The first group (n = 32; 49%) comprised cows negative for bacteria at weeks 5 and 7 pp. The second group (n = 11; 17%) comprised cows with bacterial infections at week 5 pp but that were clear of infection at week 7 pp. The third group (n = 12; 19%) comprised cows without bacteria at week 5 pp but that acquired an infection by week 7 pp. The fourth group (n = 10; 15%) comprised cows with
bacterial infections at weeks 5 and 7 pp (persistence of infection). A positive correlation (P < 0.001) was noted between the severity of cytologically determined endometritis, purulent vaginal discharge and the persistence of infection. Cows with persistent infections had a significantly (P < 0.01) prolonged luteal phase compared with cows without infection. In conclusion, the prevalence of cytologically determined endometritis and prolonged luteal phase were significantly increased in cows with persistent infections. 相似文献
826.
Asano M Tsubota T Komatsu T Katayama A Okano T Nakamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):433-435
The effect of anesthetizing with a 1:1 combination of tiletamine hydrochloride and zolazepam hydrochloride (TZ) was evaluated in 75 Japanese black bears. TZ was administered to 43 captive and 11 wild, 8 captives and 13 hibernating captive bears at the doses of approximately 9.0 mg/kg (usual dosage), 18.0 mg/kg (high dosage) and 5.0 mg/kg (low dosage), respectively. Sufficient anesthetic effects were achieved in all bears, and rectal temperatures, heart rates and respiratory rates did not change significantly during an hour handling. Complete blood cell examinations showed no abnormal data. A combination of TZ would be an efficient and safe drug for chemical immobilization of Japanese black bears. 相似文献
827.
828.
829.
Tadao Wagatsuma Matsuo Uemura Wataru Mitsuhashi Masayoshi Maeshima Satoru Ishikawa Takeshi Kawamura Tetsuya Murayama Yoshihito Shiono Md. Shahadat Hossain Khan Keitarou Tawaraya 《Soil Science and Plant Nutrition》2005,51(1):135-139
It has been suggested that plasma membrane (PM) lipids play a major role in aluminum (Al) tolerance; however, no direct investigations have been carried out using PM lipids from root-tips. Here we report a new technique for PM isolation as an alternative to the laborious two-polymer phase partitioning method that is commonly applied, as follows: 1) separation of protoplasts from 1-cm root-tip portions by enzymatic digestion, 2) attachment of the purified protoplasts to glass plates coated with polylysine, 3) preparation of PM ghosts by successive burst of the attached protoplasts using three separate buffer solutions (25 mM PIPES, 5 mM EDTA, and 2 mM MgCl2 , at pH 7.0) with slow stirring for 60 s. The PMs were confirmed to be devoid of organelle membranes by fluorescence microscopy, thin layer chromatography (TLC) and western blot analysis. The PM lipids obtained were found to be useful for studies on their differential permeability and lipid composition between lines of triticale or cultivars of maize under Al stress. 相似文献
830.
Studies of the constituents of Uruguayan propolis 总被引:4,自引:0,他引:4
Kumazawa S Hayashi K Kajiya K Ishii T Hamasaka T Nakayama T 《Journal of agricultural and food chemistry》2002,50(17):4777-4782
Eighteen flavonoids including two new compounds, four aromatic carboxylic acids, and eleven phenolic acid esters including one new compound were isolated and identified from the ethyl acetate soluble fraction of the 70% ethanol extract of Uruguayan propolis. The new compounds were elucidated as pinobanksin 3-(2-methyl)butyrate (1; recently reported in Usia, T.; Banskota, A. H.; Tezuka, Y.; Midorikawa, K.; Matsushige, K.; Kadota, S. J. Nat. Prod. 2002, 65, 673-676) pinobanksin 3-isobutyrate (2), and 2-methyl-2-butenyl ferulate (24). The constituents isolated from Uruguayan propolis in this study were similar to those of propolis of European and Chinese origin. Thus, it is suggested that the Uruguayan propolis has a plant origin similar to those of propolis from Europe and China. 相似文献