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1.
Phytochrome action in fully de-etiolated sunlight-grown potato (Solanum tuberosum L.) was studied by comparing wild-type (WT) plants and transgenic plants with either a sense or an anti-sense phytochrome A (phyA) construction. Radial stem growth, anthocyanin levels, and sucrose-phosphate-synthase activity were directly related to the levels of phyA (severely reduced in transgenics with anti-sense phyA, normal in WT and increased in transgenic with sense phyA). In contrast, longitudinal stem growth was inversely related to the levels of phyA. Phytochrome A influenced stem-extension growth responses to red/far-red ratios perceived by stable phytochrome[s]. First, far-red light reflected by non-shading neighbours promoted stem growth in WT plants but transgenic plants with either increased or reduced phyA levels failed to respond to this light signal. Second, plants with low phyA levels also showed impaired sensitivity to reductions in end-of-day red/far-red ratios. In addition, phyA appears to perceive changes in irradiance reaching the stem: lowering the amount of red plus far-red light reaching the stem promoted stem growth in WT plants. This effect was exaggerated in phyA overexpressors and absent in phyA underexpressors. Thus, phyA is active in fully de-etiolated, sunlight-grown plants. Received: 4 October 1997 / Accepted: 24 October 1997  相似文献   

2.
目的:探究痰热清对慢性阻塞性肺疾病发作加重期(AECOPD)患者的症状、血气、肺功能指标及炎症反应的影响。方法:选择2017年10月至2018年10月在本院就诊的AECOPD患者共100例,将其随机分为A组(对照组)和B组(研究组),每组各50例。A组进行常规治疗,B组在A组治疗方案的基础上给予痰热清治疗,比较两组患者的治疗效果、治疗前后血气指标、肺功能及血清炎症因子水平的变化。结果:治疗后,B组咳嗽、呼吸困难和啰音消失时间显著性短于A组(P0.05);两组血氧饱和度(SpO_2)均较治疗前显著上升(P0.05),动脉血二氧化碳分压(PaCO_2)、血清白细胞介素-1(IL-1)、C反应蛋白(CRP)和降钙素(PCT)水平均较治疗前显著降低(P0.05),且B组SpO_2显著高于A组(P0.05),PaCO_2及血清IL-1、CRP及PCT水平均显著低于A组(P0.05)。结论:痰热清辅助常规治疗可显著改善AECOPD患者临床症状,有效改善肺功能,减轻炎症反应。  相似文献   

3.
摘要 目的:探讨慢性乙型肝炎(CHB)患者血清白细胞介素-17A (IL-17A)、高尔基体蛋白73(GP73)水平与肝功能指标及病情严重程度的关系。方法:选取2018年10月至2019年10月于青海大学附属医院就诊的CHB患者93例作为研究对象(CHB组),另选取同时期于我院体检的健康志愿者33例作为对照组。比较不同病情严重程度、不同乙型肝炎e抗原(HbeAg)表达的CHB患者IL-17A、GP73水平及肝功能相关指标[丙氨酸氨基转移酶(ALT)、门冬氨酸氨基转移酶(AST)、白蛋白、总胆红素(TBiL)]的差异,并分析IL-17A、GP73水平与患者病情严重程度及肝功能相关指标的相关性。结果:CHB组中轻度、中度、重度患者血清IL-17A、GP73、ALT、AST及TBiL水平均高于对照组,白蛋白水平低于对照组(P<0.05),并且随着CHB患者病情严重程度的加重其血清中IL-17A、GP73、ALT、AST及TBiL水平逐渐升高,白蛋白水平逐渐降低(P<0.05)。CHB组HbeAg阴性患者血清中的IL-17A、GP73、ALT及AST水平均明显高于HbeAg阳性患者(P<0.05),而白蛋白和TBiL水平无明显差异(P>0.05)。CHB患者血清IL-17A、GP73均与ALT、AST及TBiL呈正相关,与白蛋白呈负相关,与患者病情严重程度呈正相关(P<0.05)。结论:CHB患者血清中IL-17A、GP73水平明显升高,且与患者病情严重程度及肝功能相关指标呈明显相关性,临床中可联合检测用于患者病情评估及预后监测。  相似文献   

4.
The benthic macroinvertebrate community (BMI) in a freshwater coastal dune lake without a surface outlet was investigated in May and October, 1986. Fifty-three invertebrate taxa were identified from Carter Lake, including three euryhaline crustacean species (Corophium spinicorne, Gnorimosphaeroma oregonensis lutea, and Acanthomysis awatchensis). Corophium spinicorne dominated the BMI communities of the littoral zones and sphaeriid clams dominated the deepwater community.The lake level dropped about 2.5 m between April and October. Based upon this decline, the lake bottom was divided into four major habitats: a sandy temporarily submerged littoral zone (A); a sandy submerged littoral zone (B); and mid-depth zone of mixed mud and sand and the macrophyte, Nitella (C); and a deep zone (D) with soft mud. The average density of BMI was highest in the littoral zones (A and B) in May and in zone B in October (zone A was dry). The lowest density occurred in zone D. In May, BMI biomass was highest in the littoral zones, but the biomass was highest in the mid-depth zone in October. The mid-depth zone in October. The mid-depth zone had the most diverse community.The two most abundant species in the temporarily submerged area, Corophium spinicorne and Juga plicifera, were found in greater numbers deeper in the lake after the water level dropped, suggesting migration by these species in response to changing water levels.  相似文献   

5.
Coenzyme Q10 (CoQ10) or ubiquinone, a redox component of the mitochondrial electron transport chains, is a powerful antioxidant and membrane stabilizer that may prevent cellular damage during myocardial ischemia and reperfusion therapy. Coenzyme Q10 has been used primarily as an adjuvant therapy for some cardiomyopathies. However, one of the main problems in CoQ10 administration is the high variability of endogenous plasma and tissue levels, which seems to be dependent on several factors. This work explores temporal 24h and seasonal variation as well as gender and racial differences in endogenous plasma ubiquinone concentration. Coenzyme Q10 measurements (quantified by HPLC-UV) of 16 healthy volunteers were done during the daytime hours of activity beginning at 09:00h one day and ending at 09:00h the next day (13 different determinations) in two distinct months, April and October, of the year. A statistically significant circadian rhythm in plasma ubiquinone concentration that includes only the fundamental 24h component was demonstrated both in the April and October data. Furthermore, the time-point means of the ubiquinone concentration in the October study were invariably higher than those obtained in the April study. No statistically significant differences were found in CoQ10 concentration between male and female subjects, both in April and in October. In addition, racial differences were demonstrated; lower plasma ubiquinone levels were found in Caucasian compared to African subjects. However, the latter small group of subjects failed to demonstrate a circadian rhythm, neither in the April nor in the October analysis.  相似文献   

6.
Coenzyme Q10 (CoQ10) or ubiquinone, a redox component of the mitochondrial electron transport chains, is a powerful antioxidant and membrane stabilizer that may prevent cellular damage during myocardial ischemia and reperfusion therapy. Coenzyme Q10 has been used primarily as an adjuvant therapy for some cardiomyopathies. However, one of the main problems in CoQ10 administration is the high variability of endogenous plasma and tissue levels, which seems to be dependent on several factors. This work explores temporal 24h and seasonal variation as well as gender and racial differences in endogenous plasma ubiquinone concentration. Coenzyme Q10 measurements (quantified by HPLC-UV) of 16 healthy volunteers were done during the daytime hours of activity beginning at 09:00h one day and ending at 09:00h the next day (13 different determinations) in two distinct months, April and October, of the year. A statistically significant circadian rhythm in plasma ubiquinone concentration that includes only the fundamental 24h component was demonstrated both in the April and October data. Furthermore, the time-point means of the ubiquinone concentration in the October study were invariably higher than those obtained in the April study. No statistically significant differences were found in CoQ10 concentration between male and female subjects, both in April and in October. In addition, racial differences were demonstrated; lower plasma ubiquinone levels were found in Caucasian compared to African subjects. However, the latter small group of subjects failed to demonstrate a circadian rhythm, neither in the April nor in the October analysis.  相似文献   

7.
Summary Four 46,XY siblings with congenital bilateral megalorchidia, macrogenitosomia, and severe mental deficiency were investigated. The testicular size was significantly larger than age-matched normal males. A normal hypothalamic-pituitary gonadotropin function was demonstrated by the finding of normal levels of luteinizing and follicle-stimulating hormones in blood samples drawn at frequent intervals and by normal responses to gonadotropin-releasing hormone and testosterone adminstration. A normal testicular function was shown by the finding of normal (a) plasma testosterone and estradiol levels, (b) gonadal response to human chorionic gonadotropin, (c) sperm analysis, and (d) morphology and cell architecture of the testes. Adrenal function was found to be within normal limits. These results demonstrated the existence of normofunctional testicular hyperplasia. The family studies suggested that this distinct congenital disorder is inherited as an X-linked recessive trait.Presented at the annual meeting of the American Society of Human Genetics, Baltimore, Md., October 8–11, 1975. Abstract published in: Amer. J. hum. Genet., 27/6, 23A (1975).  相似文献   

8.
BACKGROUND: The effect of perchlorate in drinking water on neonatal blood thyroid-stimulating hormone (thyrotropin; TSH) levels was examined for Las Vegas and Reno, Nevada. METHODS: The neonatal blood TSH levels in Las Vegas (with up to 15 microg/L (ppb) perchlorate in drinking water) and in Reno (with no perchlorate detected in the drinking water) from December 1998 to October 1999 were analyzed and compared. The study samples were from newborns in their first month of life (excluding the first day of life) with birth weights of 2, 500-4,500 g. A multivariate analysis of logarithmically transformed TSH levels was used to compare the mean TSH levels between Las Vegas and Reno newborns, with age and sex being controlled as potential confounders. RESULTS: This study of neonatal TSH levels in the first month of life found no effect from living in the areas with environmental perchlorate exposures of 相似文献   

9.
目的:研究地特胰岛素联合二甲双胍治疗妊娠糖尿病的临床疗效及对患者血清内脂素、抵抗素、血脂水平的影响。方法:选择2016年10月至2017年10月在我院进行治疗的妊娠糖尿病患者120例,按照随机数表法分为观察组和对照组。对照组给予二甲双胍治疗,观察组以对照组为基础联合地特胰岛素治疗。治疗后,观察和两组的临床疗效及不良反应的发生情况,治疗前后血清内脂素、抵抗素水平以及血脂血糖水平的变化。结果:治疗后,观察组总有效率(96.67%)明显高于对照组(85.00%)(P0.05);观察组血清内脂素、抵抗素、总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)、空腹血糖及餐后2h血糖水平均显著低于对照组(P0.05),HDL-C水平明显高于对照组(P0.05);两组不良反应发生率比较差异无统计学意义(P0.05)。结论:与单用二甲双胍相比,地特胰岛素联合二甲双胍治疗妊娠糖尿病可有效调节患者血脂血糖水平,降低血清内脂素与抵抗素水平,从而显著提高临床疗效,且安全性较好。  相似文献   

10.
The nitrite ion content and activity of nitrate reductase and nitrite reductase were examined in scutellum-derived calluses of rice varieties using a modified R2 medium (medium A) and a medium derived from the modified R2 medium (medium B). In medium A, marked differences were observed in callus growth between the varieties. The calluses of the poor-growth varieties accumulated significantly more nitrite ions during the culture period than did the good-growth varieties. Callus growth rate was negatively correlated with the nitrite ion content, indicating that the calluses of the poor-growth varieties were injured by toxic nitrite ions, which lead to browning and inhibited growth. The calluses of the poor-growth varieties had significantly lower levels of nitrite reductase activity than good-growth varieties. On the other hand, no between-group differences were observed in the nitrate reductase activity. These results indicate that the higher nitrite ion levels observed in the poor-growth varieties resulted from a lower ability to reduce nitrite and that nitrite reductase activity is one of the physiological factors that correlates with differences between varieties in rice cell cultures. In medium B, the calluses of the poor-growth varieties grew as well as the good-growth varieties, but also had significantly lower levels of nitrite reductase. Nitrate reductase activity was repressed in the calluses of both varieties in medium B compared to culture in medium A. The results suggest that repressed nitrate reductase activity causes the calluses of poor-growth varieties to accumulate only trace amounts of nitrite ions despite lower nitrite reductase activity and as a result, callus growth improved in medium B. Received: 28 July 1998 / Revision received: 14 October 1998 / Accepted: 27 October 1998  相似文献   

11.
Intact sexually mature New Zealand White male rabbits, raised under natural lighting and temperature conditions, were isolated and housed in air-conditioned quarters, in a 12-h light:12-h dark cycle. Push-pull cannulae were implanted towards the tuberal region of the hypothalamus, and animals were perfused with modified Krebs'-Ringer phosphate medium for an average period of 4 h. Most rabbits were repetitively perfused over an average period of 3.7 months. Perfusions were grouped into seasonal periods of about 40 or 80 days through the entire 1-year cycle: (A) 23 November to 31 December (winter solstice period: N = 6), (B) 1 January to 23 March (winter: N = 10), (C) 24 March to 13 June (spring: N = 9), (D) 14 June to 23 July (summer solstice period: N = 23), (E) 24 July to 13 October (late summer-early fall: N = 7) and (F) 14 October to 22 November (fall: N = 4). Maximal and minimal values of mean release, mean amplitude and mean frequency from every animal in each block were obtained. In the summer solstice group (D), maximal mean (+/- s.e.) LHRH release levels were significantly greater (14.42 +/- 6.62 pg/10 min) than for all groups (A, 0.76 +/- 0.27; B, 1.59 +/- 0.39; C, 1.34 +/- 0.22; E, 1.33 +/- 0.33; and F, 1.18 +/- 0.11) while during the winter solstice period (A), minimal mean LHRH release levels (0.48 +/- 0.04 pg/10 min) were significantly lower than in all other groups (B, 1.43 +/- 0.41; C, 0.96 +/- 0.11; D, 7.25 +/- 4.12; E, 1.18 +/- 0.37; and F, 1.18 +/- 0.11). Maximal values were highest during the summer solstice period while the minimal values were lowest during the winter solstice period. The amplitude and frequency of the LHRH pulses showed changes similar to those observed with the mean LHRH release. For 1 year, an estimated left testis weight was measured in 4-7 rabbits every 2-5 weeks. The percentage estimated testis weight peaked in early August and reached minimal levels during the winter months. These data demonstrate that the rabbit LHRH neural apparatus is very sensitive to seasonal influences although animals remained in a fixed photoperiod during the entire duration of the experiment.  相似文献   

12.
 Jasmonic acid (JA) and its methyl ester (MeJA) at concentrations ranging from 0.001 to 10 μM provoked large increases in methylputrescine levels in normal and hairy roots of Hyoscyamus muticus L.; generally, levels of free putrescine and perchloric acid-soluble conjugated putrescine, spermidine and spermine also increased dramatically. More 14C-putrescine was formed when hairy roots were incubated with labelled ornithine than with arginine; conjugated 14C-putrescine was also rapidly formed. In accord with these results, ornithine decarboxylase (EC 4.1.1.17) activity was higher than that of arginine decarboxylase (EC 4.1.1.19), and MeJA enhanced these activities about two- and fourfold, respectively. Although treatment of root cultures with jasmonates enhanced precursor (putrescine, methylputrescine) levels and accumulation of secondary metabolites such as acid-soluble conjugated di-/polyamines, it provoked only modest increases in tropane alkaloid tissue levels. Received: 24 March 1999 / Revision received: 5 October 1999 / Accepted: 26 October 1999  相似文献   

13.
The effects of disturbance on interspecific relationships between abundance and occupancy are tested using the results of a factorial experiment carried out with microcosm communities of protists. A positive relationship was documented whether marked disturbance was present or not; the pattern was neither a product of disturbance, nor was it destroyed by disturbance. Coefficients of determination, and the slopes and intercepts of abundance-occupancy relationships did not appear to change systematically with treatment. This robustness of the relationship may reflect the tendency for species to maintain approximately the same relative abundances and levels of occupancy in a broad range of circumstances. Received: 4 October 1996 / Accepted: 29 April 1997  相似文献   

14.
The objective of this study was to evaluate the efficacy of combinations of PMSG treatment and ram contact on the reproductive performance of progestagen-treated ewes during three different times of the year, Febraury (early anestrus), July (late anestrus) and October (breeding season). A total of 109 multiparous Dorset ewes was used. Ewes were treated with intravaginal progestagen pessaries for 12 days, injected with 500 IU PMSG at pessary removal and either isolated from rams prior to mating (n = 12, February; n = 12, July; n = 8, October) or exposed to rams during pessary treatment (n = 17, February; n = 12, July; n = 8, October). A third treatment group (n = 18, February; n = 6, July; n = 8, October) received pessaries and ram exposure but no PMSG. An additional treatment of progestagen pessaries alone was included in October (n = 8). There were no differences among treatments in their ability to induce estrus at different times of the year, but incidence of estrus tended (P < 0.10) to be lower for PMSG treatment during the July breeding. During February, the use of pessaries with PMSG treatment increased (P < 0.05) conception and lambing rates, whereas ram contact was without any beneficial effects. The trend was reversed during July breeding, when ram contact increased (P < 0.05) fertility of progestagen-treated ewes compared with other treatment combinations. Pessaries alone were sufficient to attain acceptable levels of fertility and fecundity in October.  相似文献   

15.
Fruits, leaves and bark forming part of the diet of chimpanzees were collected and it was noted whether samples were of a kind being eaten or not eaten. Samples were dried and analysed for condensed tannin content and for three sugars, glucose, sucrose and fructose. It was found that chimpanzees did not select foods according to the level of tannins but did so according to the levels of sugars, preferring the higher levels. Fig seeds contained higher tannin levels than fig pulp, and the chimpanzees made oral boli (“wadges”) of fig seeds which they spat out. Two fig species were compared: the one with lower tannin and higher sugar content was preferred. The bark of one tree species often eaten contained high levels of tannins but also contained sugars. Young leaves with lower tannin levels were preferred to mature leaves with higher levels. Chimpanzees appear to be able to tolerate higher tannin levels than three monkey species in this forest, and considerably higher levels than marmosets (Callitrichidae). Received: 20 October 1997 / Accepted: 1 March 1998  相似文献   

16.
目的:研究双侧股神经阻滞术用于双膝关节置换术患者麻醉效果和对患者血清炎性因子水平的影响。方法:选择2015年10月~2018年10月在我院进行双膝关节置换术的110例患者,按照其入院顺序经随机数字表法分为两组,每组55例。对照组采用全身麻醉,研究组采用双侧股神经阻滞联合全身麻醉。比较两组的麻醉情况,治疗前后血清炎性因子白介素6(IL-6)、C反应蛋白(CRP)、舒张压(DBP)、收缩压(SBP)、心率(HR)水平的变化。结果:两组麻醉时间比较差异无统计学意义(P0.05);研究组拔管、恢复室停留和苏醒时间均显著短于对照组(P0.05)。两组术后24 h、48 h血清炎性因子IL-6、CRP水平均高于术前,但研究组以上指标均显著低于对照组(P0.05);两组术中DBP、SBP、HR水平均较术前显著降低(P0.05),但研究组DBP、SBP、HR水平均显著高于对照组(P0.05),两组术后DBP、SBP、HR水平比较差异均无统计学意义(P0.05)。结论:与单纯采用全身麻醉相比,双侧股神经阻滞可有效改善双膝关节置换术患者的麻醉效果,并降低其血清炎症因子和稳定其血流动力学。  相似文献   

17.
Phytoplankton of the Barents Sea - the end of a growth season   总被引:2,自引:2,他引:0  
 Few phytoplankton investigations have been carried out at the end of the growth season, particularly in the Arctic. In the present study, we monitored the phytoplankton distribution in relation to environmental conditions in the Barents Sea in September 1988 and October 1987. An ice-edge bloom was found in September at 80° N in a stratified meltwater layer, lasting until new ice formation and southward advection of the ice cover commenced in the middle of the month. Phytoplankton populations in the marginal ice zone at this time were not nutrient limited, but biomass was probably reduced due to grazing by small copepods. Lower chl/C and chl/N ratios in the phytoplankton above the pycnocline than below in September indicated light-adapted populations. In October the particulate matter was rich in carbon, but had low chlorophyll content, indicating high levels of detritus. The hydrographic conditions in October differed greatly from those observed in September. The combination of freezing and mixing resulted in higher salinity and nutrient concentrations, and caused a homogeneous distribution, as well as reduction, of the phytoplankton stocks in the upper water column. During late October, low incoming radiation, combined with deep vertical mixing, resulted in light-limiting conditions for the algae, eventually stopping photosynthesis and terminating the growth season in the northern Barents Sea. Received: 1 March 1996/Accepted: 19 May 1996  相似文献   

18.
摘要 目的:探讨血清半乳糖凝聚素-3(Gal-3)、氨基末端脑钠肽前体(NT-pro-BNP)、超敏C反应蛋白(hs-CRP)水平与慢性心力衰竭超声心动图指标的相关性。方法:选择2018年2月~2019年10月我院收治的慢性心功能衰竭患者112例作为研究组,按美国心脏病协会(NYHA)分级分为Ⅱ级组43例、Ⅲ级组39例、Ⅳ级组30例,另选择同期我院体检的健康人员60例作为对照组,比较研究组和对照组及不同心功能分级的慢性心力衰竭患者血清Gal-3、NT-pro-BNP、hs-CRP 水平和超声心动图指标,分析慢性心力衰竭患者上述指标之间的相关性。结果:研究组血清Gal-3、NT-pro-BNP、hs-CRP水平显著高于对照组,E峰与A峰比值(E/A)及左心室射血分数(LVEF)显著低于对照组(P<0.05)。随NYHA分级增加,慢性心力衰竭患者血清Gal-3、NT-pro-BNP、hs-CRP水平逐渐升高,E/A和LVEF逐渐降低(P<0.05)。经Pearson相关性分析显示,慢性心功能衰竭患者血清Gal-3、NT-pro-BNP、hs-CRP分别与E/A、LVEF水平呈负相关关系(P<0.05)。结论:慢性心力衰竭患者血清Gal-3、NT-pro-BNP、hs-CRP水平异常升高,与超声心动图指标相关,检测Gal-3、NT-pro-BNP、hs-CRP有助于慢性心力衰竭的诊断和病情评估。  相似文献   

19.
Shake flask cultivation of the facultative methylotroph Methylobacterium sp. RXM was carried out by using a statistical experimental design to investigate the role of metal association on the formate dehydrogenase (FDH) levels. The maximal values of FDH activity were obtained for tungsten concentration up to 0.6 μM and for molybdenum concentration between 0.6 and 0.9 μM. The negative polynomial parameter (β2) for tungsten compared with the positive polynomial parameter (β1) for molybdenum on the FDH activity suggested that the latter metal exerts a stronger influence on the enzyme stimulation than the tungsten metal. A negative interaction between both metals was found, suggesting that tungsten and molybdenum shared an antagonistic effect on the enzyme activity. Received: 21 October 1997 / Accepted: 8 December 1997  相似文献   

20.
目的:分析替格瑞洛联合比伐芦定用于急性ST段抬高型心肌梗死(STEMI)患者急诊行经皮冠状动脉介入手术(PCI)的疗效。方法:回顾性分析2016年10月-2017年10月我院收治的71例行急诊PCI的STEMI患者,根据药物使用方案的不同分为研究组(n=35)和对照组(n=36),两组术前均给予患者阿司匹林300 mg和替格瑞洛180 mg进行治疗,对照组术中采用肝素,研究组术中采用比伐卢定,对比两组患者的无复流发生率、内皮素(ET)、超氧化物歧化酶(SOD)、细胞间黏附分子-1(ICAM-1)、C反应蛋白(CRP)水平、心脏功能和主要不良心脏事件发生率。结果:研究组PCI术后的无复流发生率[8.6%(3/35)]显著低于对照组[27.8%(10/36)](P0.05),术后左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、血清ICAM-1、CRP、ET水平均明显低于术前,且均显著低于对照组(P0.05),术后左心室射血分数(LVEF)、血清SOD水平高于术前,且显著高于对照组(P0.05)。研究组术后3个月的主要不良心脏事件发生率[11.4%(4/34)]低于对照组[27.8%(10/36)](P0.05)。结论:在STEMI患者急诊行PCI术中,采用替格瑞洛联合比伐芦定进行治疗可有效降低患者的无复流发生率,减轻血管壁的炎性反应,改善心脏功能,且患者的主要不良心脏事件发生率较低。  相似文献   

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