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81.
从理论上推导出以着色导管数计算导管长度的关系式,为注入颜料法测定植物导管长度分布规律了理论基础,并推导了导管长度分布规律,以及着色导管数与样品长度关系。以香梓、梧桐为试材,研究了导管长主工分布规律,实验结果与理论结果完全一致,表明理论推导和实验结果是可靠的。  相似文献   
82.
Zingiber officinale is a model spice herb, well known for its medicinal value. It is primarily a vegetatively propagated commercial crop. However, considerable diversity in its morphology, fiber content and chemoprofiles has been reported. The present study explores the utility of EST-derived markers in studying genetic diversity in different accessions of Z. officinale and their cross transferability within the Zingiberaceae family. A total of 38,115 ESTs sequences were assembled to generate 7850 contigs and 10,762 singletons. SSRs were searched in the unigenes and 515 SSR-containing ESTs were identified with a frequency of 1 SSR per 25.21 kb of the genome. These ESTs were also annotated using BLAST2GO. Primers were designed for 349 EST-SSRs and 25 primer pairs were randomly picked for EST SSR study. Out of these, 16 primer pairs could be optimized for amplification in different accessions of Z. officinale as well as other species belonging to Zingiberaceae. GES454, GES466, GES480 and GES486 markers were found to exhibit 100% cross-transferability among different members of Zingiberaceae.  相似文献   
83.
The neuropeptide arginine vasopressin (AVP) influences many social behaviors through its action in the forebrain of mammals. However, the function of the homologous arginine vasotocin (AVT) in the forebrain of fishes, specifically the telencephalon remains unresolved. We tested whether the density of AVT-immunoreactive (-ir) fiber varicosities, somata size or number of AVT-ir neuronal phenotypes within the forebrain were predictive of social behavior in reproductive males of seven species of butterflyfishes (family Chaetodontidae) in four phylogenetic clades. Similar to other fishes, the aggressive (often territorial) species in most cases had larger AVT-ir cells within the gigantocellular preoptic cell group. Linear discriminant function analyses demonstrated that the density of AVT-ir varicosities within homologous telencephalic nuclei to those important for social behavior in mammals and birds were predictive of aggressive behavior, social affiliations, and mating system. Of note, the density of AVT-ir varicosities within the ventral nucleus of the ventral telencephalon, thought to be homologous to the septum of other vertebrates, was the strongest predictor of aggressive behavior, social affiliation, and mating system. These results are consistent with the postulate that AVT within the telencephalon of fishes plays an important role in social behavior and may function in a similar manner to that of AVT / AVP in birds and mammals despite having cell populations solely within the preoptic area.  相似文献   
84.

Background

While diabetes mellitus (DM) is a known risk factor for tuberculosis, the prevalence among TB patients in India is unknown. Routine screening of TB patients for DM may be an opportunity for its early diagnosis and improved management and might improve TB treatment outcomes. We conducted a cross-sectional survey of TB patients registered from June–July 2011 in the state of Kerala, India, to determine the prevalence of DM.

Methodology/Principal Findings

A state-wide representative sample of TB patients in Kerala was interviewed and screened for DM using glycosylated hemoglobin (HbA1c); patients self-reporting a history of DM or those with HbA1c ≥6.5% were defined as diabetic. Among 552 TB patients screened, 243(44%) had DM – 128(23%) had previously known DM and 115(21%) were newly diagnosed - with higher prevalence among males and those aged >50years. The number needed to screen(NNS) to find one newly diagnosed case of DM was just four. Of 128 TB patients with previously known DM, 107(84%) had HbA1c ≥7% indicating poor glycemic control.

Conclusions/Significance

Nearly half of TB patients in Kerala have DM, and approximately half of these patients were newly-diagnosed during this survey. Routine screening of TB patients for DM using HbA1c yielded a large number of DM cases and offered earlier management opportunities which may improve TB and DM outcomes. However, the most cost-effective ways of DM screening need to be established by futher operational research.  相似文献   
85.
Glycation is chemical reaction by which sugar molecule bonds with a protein without the help of enzymes. This is often cause to many diseases and therefore the knowledge about glycation is very important. In this paper, we present iProtGly‐SS, a protein lysine glycation site identification method based on features extracted from sequence and secondary structural information. In the experiments, we found the best feature groups combination: Amino Acid Composition, Secondary Structure Motifs, and Polarity. We used support vector machine classifier to train our model and used an optimal set of features using a group based forward feature selection technique. On standard benchmark datasets, our method is able to significantly outperform existing methods for glycation prediction. A web server for iProtGly‐SS is implemented and publicly available to use: http://brl.uiu.ac.bd/iprotgly-ss/ .  相似文献   
86.
Augmentation of intrarenal angiotensinogen (AGT) synthesis, secretion, and excretion is associated with the development of hypertension, renal oxidative stress, and tissue injury during ANG II-dependent hypertension. High salt (HS) exacerbates hypertension and kidney injury, but the mechanisms remain unclear. In this study, we determined the consequences of HS intake alone compared with chronic ANG II infusion and combined HS plus ANG II on the stimulation of urinary AGT (uAGT), renal oxidative stress, and renal injury markers. Sprague-Dawley rats were subjected to 1) a normal-salt diet [NS, n = 5]; 2) HS diet [8% NaCl, n = 5]; 3) ANG II infusion in NS rats [ANG II 80 ng/min, n = 5]; 4) ANG II infusion in HS rats [ANG II+HS, n = 5]; and 5) ANG II infusion in HS rats treated with ANG II type 1 receptor blocker (ARB) [ANG II+HS+ARB, n = 5] for 14 days. Rats fed a HS diet alone did not show changes in systolic blood pressure (SBP), proteinuria, cell proliferation, or uAGT excretion although they did exhibit mesangial expansion, collagen deposition, and had increased NADPH oxidase activity accompanied by increased peroxynitrite formation in the kidneys. Compared with ANG II rats, the combination of ANG II infusion and a HS diet led to exacerbation in SBP (175 ± 10 vs. 221 ± 8 mmHg; P < 0.05), proteinuria (46 ± 7 vs. 127 ± 7 mg/day; P < 0.05), and uAGT (1,109 ± 70 vs.. 7,200 ± 614 ng/day; P < 0.05) associated with greater collagen deposition, mesangial expansion, interstitial cell proliferation, and macrophage infiltration. In both ANG II groups, the O(2)(-) levels were increased due to increased NADPH oxidase activity without concomitant increases in peroxynitrite formation. The responses in ANG II rats were prevented or ameliorated by ARB treatment. The results indicate that HS independently stimulates ROS formation, which may synergize with the effect of ANG II to limit peroxynitrite formation, leading to exacerbation of uAGT and greater injury during ANG II salt hypertension.  相似文献   
87.

Background

In 2010, WHO expanded previously-recommended indications for anti-retroviral treatment to include all HIV-infected TB patients irrespective of CD4 count. India, however, still limits ART to those TB patients with CD4 counts <350/mm3 or with extrapulmonary TB manifestations. We sought to evaluate the additional number of patients that would be initiated on ART if India adopted the current 2010 WHO ART guidelines for HIV-infected TB patients.

Methods

We evaluated all TB patients recorded in treatment registers of the Revised National TB Control Programme in June 2010 in the high-HIV prevalence state of Karnataka, and cross-matched HIV-infected TB patients with ART programme records.

Results

Of 6182 TB patients registered, HIV status was ascertained for 5761(93%) and 710(12%) were HIV-infected. 146(21%) HIV-infected TB patients were on ART prior to TB diagnosis. Of the remaining 564, 497(88%) were assessed for ART eligibility; of these, 436(88%) were eligible for ART according to 2006 WHO ART guidelines. Altogether, 487(69%) HIV-infected TB patients received ART during TB treatment. About 80% started ART within 8 weeks of TB treatment and 95% received an efavirenz based regimen.

Conclusion

In Karnataka, India, about nine out of ten HIV-infected TB patients were eligible for ART according to 2006 WHO ART guidelines. The efficiency of HIV case finding, ART evaluation, and ART initiation was relatively high, with 78% of eligible HIV-infected patients actually initiated on ART, and 80% within 8 weeks of diagnosis. ART could be extended to all HIV-infected TB patients irrespective of CD4 count with relatively little additional burden on the national ART programme.  相似文献   
88.

Setting

Seven districts in Andhra Pradesh, South India

Objectives

To a) determine treatment outcomes of patients who fail first line anti-TB treatment and are not placed on an multi-drug resistant TB (MDR-TB) regimen, and b) relate the treatment outcomes to culture and drug susceptibility patterns (C&DST).

Design

Retrospective cohort study using routine programme data and Mycobacterium TB Culture C&DST between July 2008 and December 2009.

Results

There were 202 individuals given a re-treatment regimen and included in the study. Overall treatment outcomes were: 68 (34%) with treatment success, 84 (42%) failed, 36 (18%) died, 13 (6.5%) defaulted and 1 transferred out. Treatment success for category I and II failures was low at 37%. In those with positive cultures, 81 had pan-sensitive strains with 31 (38%) showing treatment success, while 61 had drug-resistance strains with 9 (15%) showing treatment success. In 58 patients with negative cultures, 28 (48%) showed treatment success.

Conclusion

Treatment outcomes of patients who fail a first-line anti-TB treatment and who are not placed on an MDR-TB regimen are unacceptably poor. The worst outcomes are seen among category II failures and those with negative cultures or drug-resistance. There are important programmatic implications which need to be addressed.  相似文献   
89.
Antagonism tests on agar-plates and glasshouse screening indicated that three isolates of Trichoderma harzianum varied in their ability to antagonize the take-all fungus (Gaeumannomyces graminis var. tritici). Isolate 71 which was the most effective in suppressing take-all of wheat, produced two pyrones and other undetermined analogues. Isolates of T. koningii and T. hamatum shown to suppress take-all, produced a simple pyrone compound. Although T. harzianum isolates 70 and 73 did not produce any pyrones, they reduced the disease albeit to a much lesser extent than isolate 71; with isolate 73 showing distinct host growth promotion effects. It is proposed that the success of isolate 71 of T. harzianum was related to the pyrones it produces and that the ability of isolates 70 and 73 to reduce take-all may be related to mechanisms other than those involving antibiotics.  相似文献   
90.
Enhancement of shoot and root growth of wheat seedlings by a sterile red fungus was evident even when sufficient nutrients were supplied and density of plants per pot was increased (from 15 to 30 plants per pot of 400 g soil). It is likely that production of hormonal-type substances by these fungi may be involved in the phenomenon observed.  相似文献   
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