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1.
2.
The results of a detailed analysis of 100 supernumerary limbs generated by 180° ipsilateral rotation (on the same limb stump) of regeneration blastemas is presented. The limbs were analyzed in terms of their position of origin, frequency, cartilage structure by Victoria blue staining, and muscle structure by serial sections. Single, double, or triple supernumeraries can be produced at no unique position of origin, although the posterodorsal quadrant was preferred. Four classes of supernumerary limbs were generated by such operations—normal; double dorsal or double ventral; part normal/part mirror imaged; part normal/part inverted in approximately equal frequencies. After amputation of these supernumeraries the same muscle patterns are faithfully regenerated. A hypothesis to explain the production of these abnormal limbs is proposed based on the observed phenomenon of fusion of supernumerary blastemata, but their regenerative behaviour presents problems for current models of pattern formation. Similar results have been obtained with developing limb buds and the relation between development and regeneration is discussed. 相似文献
3.
Zafar Iqbal Khan Kafeel Ahmad Muhammad Ashraf Rukhsana Parveen Zahara Bibi Irfan Mustafa 《人类与生态风险评估》2016,22(1):86-98
The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks. 相似文献
4.
Demet Tademir Ayegül Karaküük‐yidoan Mustafa Ulali Tuba Takin‐Tok Emne Eln Oru‐Emre Hasan Bayram 《Chirality》2015,27(2):177-188
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
5.
Matthias Kirsch Mustafa B. A. Djamgoz Hans-Joachim Wagner 《Cell and tissue research》1990,260(1):123-130
Summary A negative feedback interaction between luminosity type horizonatal cells (HCs) and green-sensitive cones generates the long-wavelength-sensitive depolarizing response in biphasic chromaticity type HCs. This interaction is suppressed in the dark and is potentiated by light adaptation of the retina. HCs are morphologically plastic; during light adaptation, their dendritic terminals within cone pedicles extend, giving rise to spinules. This paper examines whether there is a quantitative correlation between the time course of light-dependent formation of the spinules and enhancement of the feedback interaction. The strength of the feedback interaction in isolated retinac of the roach was determined as the neutral wavelength at which reversal of spectral response polarity occurred in biphasic HCs. A good correlation was found between the neutral wavelength and the spinule/ribbon ratios of retinae. Biphasic HCs were intracellularly stained with horseradish peroxidase and the correlative ultrastructure of the contacted pedicles was examined. Neutral wavelength was found to be correlated with the spinule number, weighted according to the number of synaptic contacts mediating feed-forward transmission. The latter was estimated from the total number of labelled Cb/H2 HC processes (central and lateral) at synaptic triads. A model in which spinules mediate the negative feedback interaction of HCs in the retina of cyprinid fish is presented. 相似文献
6.
Jamal Bayad Nicole Sabolovic Denyse Bagrel Athanase Visvikis Maria Wellman Gerard Siest 《Cell biology and toxicology》1990,6(2):157-170
Eighteen IgGl monoclonal antibodies (blabs) have been produced against gamma-glutamyl transferase (GGT) from rat kidney. They were specific to the light subunit of the enzyme with affinity constants ranging from 0.3 to 7.5 108 M–1, while they did not react with GGT from other sources i.e. human and pig kidney, rat and guinea pig liver, suggesting species and organ specificity. Two of the blabs (N° 11 and 21) lost their immunoreactivities towards rat kidney GGT in the presence of N-acetyl-neuraminic acid, while immunoreactivities of the other blabs were unchanged. Furthermore, Mabs No 11 and 21 did not react with desialylated rat kidney GGT. These findings suggest that N-acetyl-neuraminic acid is involved in the epitopes recognized by these two Mabs.Abbreviations ELISA
enzyme linked immunosorbent assay
- GGT
gamma-glutamyltransferase
- Mab
monoclonal antibody
- SDS-PAGE
sodium dodecyl sulfate-polyacrylamide gel electrophoresis 相似文献
7.
Mustafa Özilgen 《Applied microbiology and biotechnology》1988,29(6):536-543
Summary Large amounts of data indicated that most of the metabolic processes of the acidogenic (acid producing) and the solventogenic (solvent producing) fermentations were regulated by product accumulation. A simple unstructured model simulated microbial growth, product formation and substrate utilization in six different fermentations, where five different microorganisms produced various combinations of ten different products. Specific growth rates of these microorganisms decreased proportionally with overall product accumulation. The products were excreted in non-growth associated pattern. Excretion of some of these products were inhibited by the overall product accumulation similarly as the microbial growth. A substrate consumption model which considered the biomass and individually all the products as separate substrate sinks simulated the data satisfactorily. 相似文献
8.
A protein antigen of Mycobacterium leprae is related to a family of small heat shock proteins. 总被引:15,自引:4,他引:11
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A H Nerland A S Mustafa D Sweetser T Godal R A Young 《Journal of bacteriology》1988,170(12):5919-5921
The gene encoding an immunologically important 18-kilodalton protein antigen of Mycobacterium leprae has been sequenced, and the amino acid sequence of the antigen has been deduced. The 18-kilodalton antigen is strikingly similar in size and sequence to a family of eucaryotic heat shock proteins. 相似文献
9.
M Jamal 《Journal of human stress》1985,11(2):60-68
This study examined Type A and Type B differences in job performance, psychosomatic complaints, and career progression among white-collar employees (N = 218) in a field setting. Significant differences were found between Type A's and Type B's in quality of performance, effort exerted at the job, and psychosomatic complaints. Employees' cultural background and sex moderated some of the relationships observed in the study. Implications of the findings for future research on the topic are discussed. 相似文献
10.
A I Mustafa B H Ali A M Satti 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1985,81(1):167-169
Furazolidone (FZ) was given to Nubian goats at the recommended therapeutic dose of 10 mg/kg body wt, for 5 days. The animals were slaughtered 24 hr after the last dose, and their livers, gluteal muscles, kidneys and hearts analysed for FZ residues by an HPLC method with a detection limit of 0.05 micrograms g-1. The drug was detected in the muscle and liver at concentrations of 0.256 +/- 0.009, 0.101 +/- 0.016 micrograms g-1 tissue, respectively. No detectable concentrations of the drug were found in the kidney and heart. 相似文献