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201.
1. The vulnerability of softwater, oligotrophic lakes to eutrophication has caused the disappearance of many, if not most, of the unique isoetid plant communities. We tested whether the presence or disappearance of the isoetid Littorella uniflora (L.) could be predicted from environmental parameters, soil types and land use in the catchment area, and atmospheric nitrogen deposition. 2. We found that the topographic catchment area of a lake was an irrelevant unit to study effects of soil type and land use. Instead, using a GIS‐generated buffer zone around the lakes it proved feasible to classify 472 lakes into historical (if L. uniflora had disappeared) or recent (if L. uniflora was still present) Littorella lakes, based on soil type and land use. Our analysis showed that aeolian sand deposits and heath in the buffer zone favoured the presence of L. uniflora, whereas moraine clay and agriculture were strongly linked to the disappearance of L. uniflora. 3. However, in order to understand fully the presence or disappearance of L. uniflora, environmental data were needed in addition to soil types, land use and nitrogen deposition, and the use of discriminant analysis allowed us to classify 96% of the investigated lakes correctly into recent or historical sites. Alkalinity, total phosphorus, total nitrogen, aeolian sand deposits and heath were the most important parameters explaining the presence or disappearance of L. uniflora. Our analysis also indicated that eutrophication, rather than acidification, has likely caused the disappearance of L. uniflora from 218 of the 472 lakes investigated. 4. Our findings have widespread implications for the conservation or restoration of isoetid habitats and we recommend applying a wide buffer zone around lakes, with restrictions on farming and traditional forestry activities. In addition, our buffering concept may prove a useful tool for aquatic ecologists to investigate relationships between catchment features and organisms (plants, insects and amphibians) with aquatic as well as terrestrial life forms.  相似文献   
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Mucuna pruriens is a well-recognized agricultural and horticultural crop with important medicinal use. However, antinutritional factors in seed and adverse morphological characters have negatively affected its cultivation. To elucidate the genetic control of agronomic traits, an intraspecific genetic linkage map of Indian M. pruriens has been developed based on amplified fragment length polymorphism (AFLP) markers using 200 F 2 progenies derived from a cross between wild and cultivated genotypes. The resulting linkage map comprised 129 AFLP markers dispersed over 13 linkage groups spanning a total distance of 618.88 cM with an average marker interval of 4.79 cM. For the first time, three QTLs explaining about 6.05–14.77% of the corresponding total phenotypic variation for three quantitative (seed) traits and, eight QTLs explaining about 25.96% of the corresponding total phenotypic variation for three qualitative traits have been detected on four linkage groups. The map presented here will pave a way for mapping of genes/QTLs for the important agronomic and horticultural traits contrasting between the parents used in this study.  相似文献   
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Summary The occurrence and distribution of several neuropeptides and transmitter enzymes have been investigated by means of indirect immunofluorescence histochemistry in preaortal and carotid body-like paraganglia of the fetal guinea pig and the newborn pig. Preaortal paraganglia from the celiac and inferior mesenteric ganglion regions in fetal guinea pigs showed cell bodies immunoreactive (IR) for tyrosine hydroxylase (TH), dopamine -hydroxylase (DBH), neuropeptide Y (NPY), galanin (GAL) and metenkephalin (ENK). Almost all cells were IR for TH and DBH, whereas NPY-like immunoreactivity (-LI), GAL-LI and ENK-LI occurred less frequently. Direct double-labeling revealed the coexistence of NPY/GAL, NPY/ENK and GAL/ENK in paraganglion cells from the celiac and inferior mesenteric region. Nerve fibers and terminals were IR for ENK; fibers IR for calcitonin-gene-related peptide (CGRP) were present in the inferior mesenteric ganglion region. Preaortal paraganglia cells from the newborn pig showed TH-LI, DBH-LI, GAL-LI and ENK-LI, the distribution pattern being similar to that seen in the guinea pig; however, NPY-LI was absent. Carotid-body-like paraganglia from the newborn pig showed cell bodies IR to TH, GAL and ENK. Few cells were seen with DBH-LI. A rich supply of nerve fibers with CGRP-LI was present; some fibers exhibited ENK-LI and CCK-LI. In the adjacent superior cervical ganglion, ganglion cell bodies showed immunoreactivity to TH, DBH and NPY. A small number of cells were positive for GAL, CGRP and vasoactive intestinal polypeptide (VIP). Physiological activation of the paraganglia, leading to release or increase in catecholamines, may also change the content of the neuropeptides present in the paraganglia.  相似文献   
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Tumour infiltrating lymphocytes (TIL) were isolated and expanded from biopsy samples of 4 patients with metastatic melanoma. The patients were treated with autologous expanded TIL and continuous or bolus infusion of Interleukin 2 (IL-2) at a dose of 18 × 106 International Units/m2/day for 5 days starting 36–48 hours after administration of cyclophosphamide at a dose of 1 g/m2. The number of TIL infused ranged from 1010 to 5,56 × 1010 cells. Two patients had stable disease (SD) lasting for 2 1/2 and 4 months respectively and they died 24 and 13 months after therapy. One patient died during therapy due to a pseudomonas septicaemia and another patient developed progressive disease (PD). He died 3 months after the start of therapy. The side effects were substantial but most of them were reversible upon cessation of the treatment.The majority of the expanded TIL of all patients were of the CD8+ phenotype. Cutaneous metastases from two patients, removed after treatment with IL-2 and TIL, showed moderate lymphocytic infiltration also mainly of CD8+ T cells.The treatment with IL-2 and TIL is feasible, but further investigations should continue in an attempt to improve the efficacy of the therapy, to reduce toxicity and to diminish the costs and labour of the culture methods.  相似文献   
208.
1. Repeat sampling in daytime within a lily (Nuphar lutea) bed and in open water showed distinct heterogeneities in the three‐dimensional distributions of water chemistry and planktonic organisms on centimetre to decimetre scales. 2. Vertical gradients of physico‐chemical variables that did not exist at dawn developed during the day in both sites, as available nutrients were released from the sediments and were consumed towards the surface. 3. Distributions of algal standing crop suggest limitation by both nutrients and grazing. 4. Marked variability in distributions may question the assumptions often made about the homogeneity of plankton and available nutrient distributions in open water and in macrophyte stands of shallow lakes. Although simple sampling regimes for monitoring of water quality may be adequate for many purposes, they miss a fine structure in the water that is inherently interesting in understanding the underlying processes of plankton function.  相似文献   
209.
Electromyographic (EMG) muscle scanning measures 2-second samples of integrated muscle action potentials from individual neck and back muscles using a hand-held scanner with post-style surface electrodes separated by a fixed distance. This scanning technique is widely used to expeditiously assess muscle activity in the diagnosis of musculoskeletal disorders. In order to determine if the 2-second sample is sufficiently representative of electrical activity at a specific muscle site, the stability of the signal received by the hand-held scanner was measured bilaterally at six neck and back muscle sites over 40 seconds (20 2-second integration periods) in five seated subjects. Taking the overall average EMG activity as the true value, the mean number of 2-second integration periods required to achieve <5% standard error was calculated to be 1.47 for the 60 muscles tested. Only three sites required more than five integration periods. The validity of EMG scanning as a diagnostic tool is enhanced by longer integration periods  相似文献   
210.
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