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Henrik Saxe 《Physiologia plantarum》1989,76(3):362-367
The dose- and time-response effects of 3 days of 6 h day-time sequential exposures to NO2 , SO2 and SO2 +NO2 of 0.45–1.81 μl l−1 (ppm) SO2 and 1.50–7.65 μl l−1 NO2 on photosynthesis, transpiration and dark respiration were examined for nine Carpatho-Ukrainian half-sib families and a population from the GFR ('Westerhof') of Norway spruce [ Piecea abies (L.) Karst.], all in their 5th growing season.
SO2 +NO2 inhibited photosynthesis and transpiration and stimulated dark respiration more than SO2 alone. SO2 and SO2 +NO2 at the lowest concentrations inhibited night transpiration, but increased it at the highest concentration, the strongest effects being obtained with combined exposures. Photosynthesis of the different half-sib families was affected significantly differently by SO2 +NO2 exposures. NO2 alone had no effects.
Sensitivity to transpiration decline correlated negatively with branch density. Height of trees correlated postitively with decline sensitivity in the seed orchard. The distribution of photosynthesis and transpiration sensitivities over all tested half-sib families correlated negatively with the distribution of decline sensitivity of their parents in a rural Danish seed orchard. The relative photosynthesis and transpiration sensitivities may thus serve as diagnostic parameters for selecting against novel spruce decline. 相似文献
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Sensitivity to transpiration decline correlated negatively with branch density. Height of trees correlated postitively with decline sensitivity in the seed orchard. The distribution of photosynthesis and transpiration sensitivities over all tested half-sib families correlated negatively with the distribution of decline sensitivity of their parents in a rural Danish seed orchard. The relative photosynthesis and transpiration sensitivities may thus serve as diagnostic parameters for selecting against novel spruce decline. 相似文献
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One case of malignant peripheral neuroectodermal tumour successfully diagnosed by cytology is presented. Although a Papanicolaou stained smear could not lead to a diagnosis more specific than a malignant small cell tumour, ancillary analytic methods performed on the cytologic material including immunocytochemistry and electron microscopy yielded the correct diagnosis of peripheral neuroectodermal tumour. This case demonstrates that a precise categorization of small round cell tumours may be achieved by cytology as long as some material is kept for immunocytochemical and ultrastructural studies. 相似文献
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Fine needle aspiration of the male breast can present problems of diagnosis because the cytological presentation of gynaecomastia can be confused with that of adenocarcinoma. We reviewed breast aspirates from 24 male patients in order to determine the accuracy of cytology as a method of diagnosing gynaecomastia. Discrepancies were observed between the original cytology reports on one hand and the review cytology and biopsies on the other. Of the 24 aspirates from the male breast, the cytology was reported as negative in 16 cases, suspicious in three cases and malignant in five. In four cases of the negative group, a specific diagnosis of gynaecomastia was made. In two of the negative cases the subsequent biopsies revealed adenocarcinoma. Of the five cases reported on the original cytology as adenocarcinoma, two on review showed the features of florid gynaecomastia and this was confirmed on biopsy and three confirmed the initial diagnosis of adenocarcinoma. The cytological features of gynaecomastia which distinguish it from adenocarcinoma are discussed. 相似文献
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Carbon allocation in developing spruce needles. Enzymes and intermediates of sucrose metabolism 总被引:2,自引:0,他引:2
Rüdiger Hampp Bernd Egger Susanne Effenberger Werner Einig 《Physiologia plantarum》1994,90(2):299-306
In lyophilized needles of Norway spruce ( Picea abies [L.] Karsten) and starting from bud break, we determined enzyme activities (sucrose phosphate synthase [SPS; EC 2.4,1.14]. sucrose synthase [SS; EC 2.4,1.13]. acid invertase [AI; EC 3.2,1.26]) and intermediates (starch, sucrose, glucose, fructose; fructose 6-phosphate, fructose 2.6-bisphosphate [F26BP]) of carbohydrate metabolism together with needle weight, shoot length, chlorophyll and protein. For up to 110 days after bud break, samples were taken twice a week from about 25-year-old trees under field conditions. At least three periods can be distinguished during needle maturation. During the first period (up to 45 days after bud break) Al showed the highest extractable activity. This coincided with very high levels of F26BP (up to 11 pmol [mg dry weight]−1 ) and a transient increase of starch in parallel to a decrease of sucrose. The interval between 45 and 70 days after bud break was characterized by high SS activity (ratio of fructose/glucose >1), much decreased levels of F26BP (down to below 1 pmol [mg dry weight]−1 ), and a pronounced increase in the dry weight/fresh weight ratio. In parallel, starch declined and soluble carbohydrates increased. Finally, needle maturation was characterized by decreasing SS and continuously increasing SPS activities, so that the ratio of SPS/SS increased more than 6-fold. AI. however, did not decline with maturation. Changes in pool sizes of metabolites and enzyme activities (AI. SPS) are consistent with current concepts on sink/source transition. SS is obviously important with regard to the synthesis of structural polysaccharides. 相似文献
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Pine needle growth and fine structure after prolonged acid rain treatment in the subarctic 总被引:1,自引:0,他引:1
The growth and morphology of Scots pine needles were studied in a long-term acid rain experiment in the far north of Finnish Lapland. Pine trees 5 m tall of age 50–70 years were exposed, by spraying the foliage and soil from a height of 2 m, to either clean water (IC) or acidified water over the period 1985–1992, the acidification site being divided into sub-areas in which the precipitation contained two levels of either sulphuric (Sm, Sh) or nitric (Nm, Nh) acid, or both (SNm, SNh). The treatments with medium and high sulphate-S over eight consecutive years yielded a total sulphur deposition of 3·4 and 17·1 gm−2, respectively, and those with medium and high nitrate-N a total nitrogen deposition of 1·1 and 5·9 g m−2. Needles were collected for light and electron microscopy, growth measurements and morphometry. Growth in branch height had decreased by about 40% after 6 years of SNm or SNh treatment, and needle growth by 15% in the SNh trees as compared with the irrigated control trees (IC), although decreases were statistically significant only with respect to the non-irrigated control trees (DC). Growth of branches and needles was slightly better in the Nh treatment than in the IC group. The areas of the whole needle, the mesophyll and the phloem decreased in response to SNh treatment as compared with IC or DC, and a statistically significant decrease of about 30–40% was seen in the area of the xylem in comparison with DC. Cellular damage was observed following the acid treatments, especially with a high acid load. The damage was manifested in collapse of the cellular compartments, increases in lipid accumulations and swelling or disorganization of the protoplast. Increased vacuolization of the cytoplasm, plasmalemma irregularities and chilling-type damage to the mitochondria were also observed. 相似文献
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Two methods of storing fine needle aspirates were compared in 14 patients with breast cancer. the methods of storage were: (1) as a Cytospin slide prepared immediately from the aspirated material and stored at −80°C; (2) as a suspension of cells in tissue culture medium, stored at −80°C. the effect of storage on the cells was assessed by means of an oestrogen receptor immunocytochemical assay (ER-ICA). an ER positivity of 100% was obtained by ER-ICA staining of cells after storage method 1, whilst all of the specimens stored by method 2 were ER-negative. the data demonstrate that cells stored in tissue culture medium at −80°C are not suitable for ER measurement. the storage method of choice for specimens intended for ERICA is as a Cytospin slide. the ER status of cells deposited on Cytospin slides prepared immediately and stored at −80°C for 2 years could be demonstrated despite the delay in processing the specimen. 相似文献