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631.
Sydow O 《The FEBS journal》2008,275(7):1370-1376
Effective medical treatment for Parkinson's disease has been available for almost 40 years. After several years of treatment with L-dihydroxyphenylalanine (L-dopa, levodopa), however, fluctuations often occur. The patient may then experience random variations of the motor symptoms during the day. The medication becomes increasingly complicated. New therapeutic methods, deep brain stimulation and duodenal infusion of L-dopa, have proven to be very effective in stabilizing the fluctuations. A clinical update of Parkinson's disease is presented together with a short review of these two methods. 相似文献
632.
Hanna Karlsson Marie Emanuelsson Ulf Segerström 《Vegetation History and Archaeobotany》2010,19(2):103-119
The local vegetation history of three sites in the forested region of central Sweden was studied. These sites were the forest village site Ängersjö and the two nearby shieling sites, Gammelvallen and Öjingsvallen. The aim of the study was to elucidate the relationship between the establishment of the farm and of the shielings. The results indicate that agriculture began in the area in the Roman Iron Age or Migration period. There is evidence of contemporaneous human activity in the village of Ängersjö and the shieling at Öjingsvallen, suggesting the development of a farm–shieling system. We suggest that permanent farms and shielings were established concurrently as a local system, and that one of the main reasons was to demonstrate that the territory between the farm and the shieling was a potential resource area belonging to the farm. The problems of using pollen to differentiate between a shieling and a farm are also evaluated and it is concluded that multiple sites as well as a multidisciplinary approach is essential in order to be able to address such complex problems as the emergence of the farm–shieling system. 相似文献
633.
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635.
Olof Ryding 《Nordic Journal of Botany》1992,12(3):273-298
The pericarp structure has been investigated in about 205 species, representing 43 out of the about 50 genera of Lamiaceae subfamily Nepetoideae tribe Ocimeae (Ocimoideae). In its basic structure, the pericarp of Ocimeae corresponds to that of other Nepetoideae. The exocarp has usually both mucilaginous and non-mucilaginous cells. Below it, there are soft cells (mesocarp), a layer of vertically arranged bone cells and a thin innermost cell layer. The differences discovered in pericarp anatomy essentially agree with the traditional subdivisions of Ocimeae (by e.g. Briquet). The subtribes Hyptidinae and Ociminae and the genus Aeollanthus (in subtribe Plectran-thinae) have, with few exceptions crystals in the bone cells. Unlike other Labiatae, Plectranthinae (except Alvesia, Isodon and Siphocranion ) has a plate-like content in the mucilaginous cell. The systematic position of the latter three genera is discussed. Because of their pericarp anatomy, Hoslundia, Fuerstia, Catoferia, Nosema, Benguellia, Octomeron and Ceratanthus are suggested to belong to Ociminae, and Neohyptis to Plectranthinae. On the basis of pericarp characters an informal division of Ociminae is suggested. Considering the distribution of stamen and pericarp characters, the genera Capitanya, Pycnostachys and Solenostemon are suggested to originate from Plectranthus. Ocimeae species which grow in arid habitats tend to produce more mucilage and to have a larger plate-like content in the mucilaginous cells than species from moist or wet habitats. 相似文献
636.
637.
The present study demonstrates that endogenous production of IL-12 is crucial for survival in Staphylococcus aureus-induced arthritis in mice. Staphylococcal load is enhanced in several organs, because of lack of IL-12. This might be due
to decreased production of IFN-γ in IL-12-deficient mice. Although IL-12-deficient mice were exposed to higher staphylococcal
load, they demonstrated no increased severity of arthritis as compared with control animals. 相似文献
638.
639.
Response to directional light by leaves of a sun-tracking lupine (Lupinus succulentus) 总被引:3,自引:0,他引:3
Experiments were done to examine the phototrophic response of sun-tracking leaves of Lupinus succulentus Dougl. to fixed beams of white and broad band light. Upon irradiation with 15 W m−2 white light that struck the laminae at an angle of 45°, there was a 45–60 min lag period prior to leaf movement. The greatest rate of movement was 15° h−1 , and reorientation ceased when leaves attained a position within 15° of perpendicular to the light beam. Laminar movement was largely pulvinar, and a 60 min inductive light treatment was sufficient to activate a maximum pulvinar response in subsequent darkness. Light striking the lamina at angles between 20 and 70° induced similar maximum pulvinar responses and only light that struck the upper (adaxial) leaf surface was effective. Leaf tracking was fully activated by blue light but not by red or yellow light. 相似文献
640.
Hans Elwing Jan Olof G. Karlsson Nils Grundstr m Albin L. E. Gustafsson Henning von Schenck Hans Sundgren Svante
dman Rolf G. G. Andersson Ingemar Lundstr m 《Biosensors & bioelectronics》1990,5(6):449-459
Certain fish scales contain specialized cells (chromatophores) with pigment granulas, which can be dispersed or aggregated in the cells. The degree of aggregation is determined by a transmitter substance, nonadrenaline, released by the sympathetic nerve endings in the skin. Isolated scales from, for example, cuckoo wrasse (Labrus ossifagus) retain a large sensitivity to externally applied nonadrenaline (or more generally catecholamines) for several weeks. The degree of aggregation in isolated scales can be measured objectively by simple photometric techniques. We demonstrate in this paper how fish scales can be used to monitor catecholamine levels in human blood plasma. A discussion of other potential biosensor applications of this intact biological receptor-effector system is also given. 相似文献