排序方式: 共有32条查询结果,搜索用时 15 毫秒
1.
The effect of lincocin (a plastid protein synthesis inhibitor) treatment on the greening process of bean (Phaseolus vulgaris L.) leaves have been studied. In comparison with control leaves treated ones had a decreased rate of chloroplast development. They had a marked chlorophyll deficiency and a decreased chlorophyll a/b ratio. Some long and short wavelength forms of chlorophyll a were lacking as evidenced from the absorption spectra at 25°C and the fluorescence spectra at 77°K. The –14CO2 fixation was inhibited by 80–90% in treated leaves. The fluorescence induced by the measuring light was greater in the treated leaves than in the control ones, and the kinetics of the decline of the relative fluorescence intensity were also different. Electron microscopic studies showed macrogranum-like structures and incomplete membrane vesicles in the treated plastids. After longer treatment a destruction of membranes was observed. The results indicate some structural and functional membrane deficiencies and instability of the membranes. 相似文献
2.
Sarder Tanzir Hossain Petros Isaakidis Karuna D. Sagili Shayla Islam Md Akramul Islam Hemant Deepak Shewade S. M. Mostofa Kamal Ashaque Husain 《PloS one》2015,10(6)
Objectives
To determine, in areas supported by BRAC, Bangladesh i) the pre-diagnosis and pre-treatment attrition among presumptive and confirmed Multi-Drug Resistant Tuberculosis (MDR-TB) patients and ii) factors associated with attrition.Methods
This was a retrospective cohort study involving record review. Presumptive MDR-TB patients from peripheral microscopy centres serving 60% of the total population of Bangladesh were included in the study. Attrition and turnaround time for MDR-TB diagnosis by Xpert MTB/RIF and treatment initiation were calculated between July 2012 and June 2014.Results
Of 836 presumptive MDR-TB patients referred from 398 peripheral microscopy centres, 161 MDR-TB patients were diagnosed. The number of diagnosed MDR-TB patients was less than country estimates of MDR-TB patients (2000 cases) during the study period. Among those referred, pre-diagnosis and pre-treatment attrition was 17% and 21% respectively. Median turnaround time for MDR-TB testing, result receipt and treatment initiation was four, zero and five days respectively. Farmers (RR=2.3, p=0.01) and daily wage laborers (RR=2.1, p=0.04) had twice the risk of having pre-diagnosis attrition. Poor record-keeping and unreliable upkeep of presumptive MDR-TB patient databases were identified as challenges at the peripheral microscopy centres.Conclusion
There was a low proportion of pre-diagnosis and pre-treatment attrition in patients with presumptive and confirmed MDR-TB under programmatic conditions. However, the recording and reporting system did not detect all presumptive MDR-TB patients, highlighting the need to improve the system in order to prevent morbidity, mortality and transmission of MDR-TB in the community. 相似文献3.
4.
5.
Adult spinal opioid receptor μ1 expression after incision is altered by early life repetitive tactile and noxious procedures in rats
下载免费PDF全文
![点击此处可从《Developmental neurobiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Nynke J. van den Hoogen Roel RI van Reij Jacob Patijn Dick Tibboel Elbert A. J. Joosten 《Developmental neurobiology》2018,78(4):417-426
Clinical and experimental data suggests that noxious stimulation at critical stages of development results in long‐term changes on nociceptive processing in later life. Here, we use an established, well‐documented rat model of repetitive noxious procedures closely mimicking the clinical situation in the NICU. In order to understand molecular changes underlying the long‐term consequences of repetitive stimulation of the developing nociceptive system the present study aims to analyze the presence of the µ‐opioid‐receptor‐1 (OPRM1). Neonatal rats received either four needle pricks per day in the left hind‐paw from postnatal day 0–7 as a model of procedural pain in infancy. Control pups were handled in the same way but were instead tactile stimulated, or were left undisturbed. At the age of 8 weeks, all animals received an ipsilateral hind‐paw incision as a model for post‐operative pain, and mechanical sensitivity was tested at multiple time‐points. Before, and 1 or 5 days post‐incision, spinal cord tissue was collected for immunostaining of opioid receptor OPRM1. Semi‐quantitative immunocytochemical analysis of superficial laminae in lumbar spinal dorsal horn revealed that: (1) early life repetitive tactile or noxious procedures do not alter baseline levels of OPRM1 staining intensity and (2) early life repetitive tactile or noxious procedures lead to a decrease in OPRM1 staining intensity 5 days after incision in adulthood compared to undisturbed controls. We conclude that early life repetitive tactile or noxious procedures affect the intensity of OPRM1‐immunoreactivity in the lumbar superficial spinal cord dorsal horn after adulthood injury, without affecting baseline intensity. © 2018 The Authors. Developmental Neurobiology Published by Wiley Periodicals, Inc. Develop Neurobiol 78: 417–426, 2018 相似文献
6.
O'Gara BA Abbasi A Kaniecki K Sarder F Liu J Narine LH 《The Journal of experimental zoology》1999,284(7):729-741
In this study we document the sensitivity of the leech pharynx to acetylcholine and begin to characterize the acetylcholine receptor mediating this response by examining the effects of selective cholinergic agonists and antagonists on the contractile behavior of the pharynx. The order of potency derived from the EC50 of each agonist was (+/-)epibatidine > acetylcholine (in the presence of physostigmine) > McN A-343 > carbachol > nicotine. However, when response amplitude was considered, the order of potency to the tested agonists was (+/-)epibatidine > nicotine > McN A-343 > carbachol > acetylcholine. Acetylcholine-induced contractions of the pharynx were antagonized by d-tubocurarine, but not by alpha-bungarotoxin, alpha-conotoxin M1, or mecamylamine. Application of high concentrations of hexamethonium (1 mM) augmented the acetylcholine-induced contractions. However, this augmentation was apparently due to inhibition of acetylcholinesterase by hexamethonium. The muscarinic antagonist atropine produced complex actions and apparently acted as a mixed agonist/antagonist. Atropine by itself produced an increase in basal tonus and increased the frequency and amplitude of phasic contractions. Atropine increased the peak tension of the acetylcholine-induced response; however, it reduced the amplitude of both the acetylcholine-induced increase in basal tonus and integrated area. Based on the pharmacological profile of the pharyngeal acetylcholine response, we conclude that the acetylcholine receptor mediating the response is a nicotinic receptor. However, the responsiveness of the pharynx to muscarinic agents diverges from that of a classical nicotinic receptor. 相似文献
7.
研究了体外培养一种孟加拉传统香蕉(Musa spp. Cv. Kanthali)的茎尖组织。茎尖的原始细胞表面经无菌处理(0.1% HgCl2处理12min),接种6~15d后外植体地下茎部分仍有微生物污染(大部分是细菌),杀死了85%的外植体。为确定无污染培养基,将等量外植体分别浸泡在含400mg/L氨苄青霉素和200mg/L庆大霉素(两种光谱抗生素)的培养基中1h。结果表明,经抗生素处理的外植体完全没有污染,但培养3周后不能再生。进行二次继代培养后,其中一部分外植体吸收了培养基并胀大,颜色由苍白转变成浅绿或深绿。三次继代培养后数天,不再观察到外植体的生长,所有经抗生素处理过的外植体都开始死亡。在未经抗生素处理的活外植体中,单个茎发育的最佳培养基是:MS+4.0mg/L BA+0.5mg/L KT+15% CW,平均生长时间为18~21d,但再生率很低,只有30%。茎细胞增殖的最佳培养基是:MS+4.0mg/L BA+2.0mg/L IAA+15% CW,每个茎平均只萌发3~4个芽。最后,在添加0.5mg/L IBA的一半浓度的MS培养基中,体外培养茎最大生根率达到90%。 相似文献
8.
1. Egg size is often used as a proxy of egg quality although size and composition may vary, e.g. in insects egg size usually decreases as female ages. Whether this decrease in size reflects reduced concentrations of essential nutrients such as lipids and proteins of eggs laid by ageing females, or does reduced size per se explain often observed lower fitness of later laid eggs is poorly explored. 2. Egg properties were compared with fitness parameters of offspring laid on the first and fourth night during the oviposition period of a capital breeding moth, Cleorodes lichenaria (Hufnagel). The study aim was to explore whether decreased egg size is caused by decreased provisioning into later laid eggs measured as egg protein and lipid concentration, and whether it results in lower fitness of later laid offspring. 3. The fresh and dry weight of eggs decreased over the oviposition period, but the protein and lipid concentration remained constant. Survival of larvae was lower among the fourth night laid offspring on a low quality host Parmelia sulcata Taylor compared to a high quality host Ramalina fraxinea (L.) Ach. No differences were observed in egg fertility or hatchability, neonate survival without food and pupal mass between the offspring produced on different nights. 4. Decreased survival of offspring produced later was rather attributable to absolute provisioning (i.e. lower weight of eggs) than relative provisioning (i.e. decreased concentrations of nutrients in eggs). It is argued that lower survival of later laid smaller eggs on low quality diet is likely attributable to physical and chemical characteristics of host lichens and/or physical properties of tiny neonate larvae. 相似文献
9.
研究了体外培养一种孟加拉传统香蕉(Musa spp.Cv. Kanthali)的茎尖组织。茎尖的原始细胞表面经无菌处理(0.1%HgCl2处理12min) ,接种6~15d后外植体地下茎部分仍有微生物污染(大部分是细菌) ,杀死了85%的外植体。为确定无污染培养基,将等量外植体分别浸泡在含400mg/L氨苄青霉素和200mg/L庆大霉素(两种光谱抗生素)的培养基中1h。结果表明,经抗生素处理的外植体完全没有污染,但培养3周后不能再生。进行二次继代培养后,其中一部分外植体吸收了培养基并胀大,颜色由苍白转变成浅绿或深绿。三次继代培养后数天,不再观察到外植体的生长,所有经抗生素处理过的外植体都开始死亡。在未经抗生素处理的活外植体中,单个茎发育的最佳培养基是:MS 4.0mg/L BA 0.5mg/L KT 15% CW,平均生长时间为18~21d,但再生率很低,只有30%。茎细胞增殖的最佳培养基是:MS 4.0mg/L BA 2.0mg/LIAA 15% CW,每个茎平均只萌发3~4个芽。最后,在添加0.5mg/LIBA的一半浓度的MS培养基中,体外培养茎最大生根率达到90%。 相似文献
10.
V Fauveau B Wojtyniak J Chakraborty A M Sarder A Briend 《BMJ (Clinical research ed.)》1990,301(6743):103
OBJECTIVE--To examine the impact on mortality of a child survival strategy, mostly based on preventive interventions. DESIGN--Cross sectional comparison of cause specific mortality in two communities differing in the type, coverage, and quality of maternal and child health and family planning services. In the intervention area the services were mainly preventive, community based, and home delivered. SUBJECTS--Neonates, infants, children, and mothers in two contiguous areas of rural Bangladesh. INTERVENTIONS--In the intervention area community health workers provided advice on contraception and on feeding and weaning babies; distributed oral rehydration solution, vitamin A tablets for children under 5, and ferrous fumarate and folic acid during pregnancy; immunised children; trained birth attendants in safe delivery and when to refer; treated minor ailments; and referred seriously ill people and malnourished children to a central clinic. MAIN OUTCOME MEASURES--Overall and age and cause specific death rates, obtained by a multiple step "verbal autopsy" process. RESULTS--During the two years covered by the study overall mortality was 17% lower among neonates, 9% lower among infants aged 1-5 months, 30% lower among children aged 6-35 months, and 19% lower among women living in the study area than in those living in the control area. These differences were mainly due to fewer deaths from neonatal tetanus, measles, persistent diarrhoea with severe malnutrition among children, and fewer abortions among women. CONCLUSIONS--The programme was effective in preventing some deaths. In addition to preventive components such as tetanus and measles immunisation, health and nutrition education, and family planning, curative services are needed to reduce mortality further. 相似文献