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1.
A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics.  相似文献   
2.
Summary Attempts were made to store pollen grains of Crotalaria retusa L. in a mineral oil (paraffin oil) and two vegetable oils (soybean oil and olive oil). Under laboratory conditions pollen grains not stored in oil lost in vitro germinability within 15–30 days, while those stored in oils maintained some degree of germinability even after 60 days. Pollen samples stored in oils at –20° C did not show any decline in germinability or pollen tube vigour even after 6 months of storage. The results amply demonstrate the feasibility of using oils for short- and long-term pollen storage.  相似文献   
3.
    
Structural and cytochemical aspects of the pistil and detailsof pollination and pollen-pistil interaction were investigatedin the African oil palm (Elaeis guineensis Jacq.), an importantperennial oil crop. The stigma is trilobed, wet and papillate.The branched papillae are confined to a narrow linear zone oneach stigmatic lobe. Each stigmatic lobe harbours a deep stigmaticgroove, which runs adaxially along the surface. The stigmaticgroove is bordered by a well-defined layer of glandular cells,each of which has a pectinaceous cap on the inner tangentialwall. The style is hollow. The canal cells show thickeningson the inner tangential wall. The stigmatic groove and stylarcanal contain an extracellular matrix secreted by the canalcells which is rich in proteins, acidic polysaccharides andpectins. The canal cells at the base of the style are papillateand loosely fill the stylar canal. The stigma becomes receptivewhen the stigmatic lobes separate, and remains so for 24 h.Pollination is mediated by weevils as well as by the wind. Undernatural conditions the pollination efficiency was 100%. Pollinationinduces additional secretion in the stigmatic groove and stylarcanal. During post-pollination secretion, the pectinaceous capsof the cells lining the stigmatic groove are degraded. Pollengrains germinate on the stigmatic papillae and tubes grow onthe surface of the papillae, entering the stigmatic groove andadvancing along it into the stylar canal to eventually gainaccess to the locules. Pollen tubes are seen in the ovules 18–20h after pollination. Copyright 2001 Annals of Botany Company Arecaceae, Elaeis guineensis, African oil palm, pollination, stigmatic grove, stylar canal, Tenera hybrid, weevil  相似文献   
4.
Three intergeneric hybrids were produced between a cold-tolerant wild species, Erucastrum abyssinicum and three cultivated species of Brassica, B. juncea, B. carinata and B. oleracea, through ovary culture. The hybrids were characterized by morphology, cytology and DNA analysis. Amphiploidy was induced in all the F1 hybrids through colchicine treatment. Stable amphiploids and backcross progenies were obtained from two of the crosses, E. abyssinicum x B. juncea and E. abyssinicum x B. carinata. The amphiploid, E. abyssinicum x B. juncea was successfully used as a bridge species to produce hybrids with B. napus, B. campestris and B. nigra. These hybrids and backcross progenies provide useful genetic variability for the improvement of crop brassicas.  相似文献   
5.
Summary Methods currently available for evaluating pollen quality in vitro include, (a) tests of germinability; (b) tests of the stainability of the vegetative cell contents; (c) tests for enzyme activity, and (d) the fluorochromatic procedure (FCR), which tests principally the integrity of the plasmalemma of the vegetative cell. Using germinability in vitro as a standard, a comparison has been made between histochemical methods of classes (b), (c) and (d) in application to various pollens, immature, mature, and treated in ways known to affect viability and membrane state. Predictably, the lowest correlation was obtained with tests of stainability. The highest was given by the FCR, which generally provided an excellent guide to potential germinability. The FCR procedure is subject to various limitations, however, (a) A high correlation between FCR and germinability can only be expected when mature, ripe pollen is used; with immature pollen, the FCR will predict excessively high potential germinability. (b) The FCR may also predict a higher potential level of pollen function than in vitro germinability when the germination medium is sub-optimal. In this situation, however, it will generally give a better guide to fertilising capacity, (c) The FCR is not a test of pollen viability. Like germinability in vitro, it can yield a negative score with pollen which is nevertheless capable of functioning. For example, false negatives will be obtained with some species if the pollen is not properly pre-conditioned by rehydration before testing, an important point in monitoring stored pollen. The paper includes a brief discussion of the rationale of pollen testing.  相似文献   
6.

Introduction  

The vast difference in the abundance of different proteins in biological samples limits the determination of the complete proteome of a cell type, requiring fractionation of proteins and peptides before MS analysis.  相似文献   
7.
Thrombocytopenia in methotrexate (MTX)-treated cancer and rheumatoid arthritis (RA) patients connotes the interference of MTX with platelets. Hence, it seemed appealing to appraise the effect of MTX on platelets. Thereby, the mechanism of action of MTX on platelets was dissected. MTX (10 μM) induced activation of pro-apoptotic proteins Bid, Bax and Bad through JNK phosphorylation leading to ΔΨm dissipation, cytochrome c release and caspase activation, culminating in apoptosis. The use of specific inhibitor for JNK abrogates the MTX-induced activation of pro-apoptotic proteins and downstream events confirming JNK phosphorylation by MTX as a key event. We also demonstrate that platelet mitochondria as prime sources of ROS which plays a central role in MTX-induced apoptosis. Further, MTX induces oxidative stress by altering the levels of ROS and glutathione cycle. In parallel, the clinically approved thiol antioxidant N-acetylcysteine (NAC) and its derivative N-acetylcysteine amide (NACA) proficiently alleviate MTX-induced platelet apoptosis and oxidative damage. These findings underpin the dearth of research on interference of therapeutic drugs with platelets, despite their importance in human health and disease. Therefore, the use of antioxidants as supplementary therapy seems to be a safe bet in pathologies associated with altered platelet functions.  相似文献   
8.
Summary A typical style of Hypericum calycinum is solid with a core of transmitting tissue traversing the whole length of the style. This transmitting tissue consists of loosely arranged cells and large intercellular spaces filled with a secretion product. The secretion product is rich in lipids, but poor in proteins and polysaccharides. The intercellular spaces of the transmitting tissue originate partly by a separation of cells as a result of the decomposition of the middle lamella and partly by degeneration of some of the cells of the transmitting tissue. H. calycinum is self-compatible. Both self- and cross-pollinations result in profuse pollen germination on the stigma and pollen tube growth through the style. The data on Hypericum is discussed in relation to information available on other solidstyled systems.  相似文献   
9.
Molecular Biology Reports - Endophytic fungal interaction with medicinal plant resulting in the production of bioactive compounds influenced the present study. Endophytic fungus Penicillium...  相似文献   
10.
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