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921.
Background
There is an ongoing discussion about age limits for deep brain stimulation (DBS). Current indications for DBS are tremor-dominant disorders, Parkinson's disease, and dystonia. Electrode implantation for DBS with analgesia and sedation makes surgery more comfortable, especially for elderly patients. However, the value of DBS in terms of benefit-risk ratio in this patient population is still uncertain. 相似文献922.
Baughman RP 《Arthritis research & therapy》2007,9(Z2):S8
Pulmonary involvement is common in sarcoidosis, an immune-mediated inflammatory disorder that is characterized by non-caseating granulomas in tissue. Sarcoid patients with advanced pulmonary disease, especially end-stage pulmonary fibrosis, risk developing pulmonary hypertension (World Health Organization group III pulmonary hypertension secondary to hypoxic lung disease). Increased levels of endothelin (ET)-1 in plasma and bronchoalveolar lavage of some sarcoid patients suggest that ET-1 may be driving pulmonary fibrosis and sarcoidosis-associated pulmonary hypertension. Although a relationship between raised levels of ET-1 and clinical phenotype is yet to be identified, early evidence from studies of ET-1 blockade with drugs such as bosentan is encouraging. Such therapy possibly could be combined with standard anti-inflammatory agents to improve outcome. 相似文献
923.
Transposon mediated transgenesis in a marine invertebrate chordate: <Emphasis Type="Italic">Ciona intestinalis</Emphasis> 下载免费PDF全文
Achievement of transposon mediated germline transgenesis in a basal chordate, Ciona intestinalis, is discussed. A Tc1/mariner superfamily transposon, Minos, has excision and transposition activities in Ciona. Minos enables the creation of stable transgenic lines, enhancer detection, and insertional mutagenesis. 相似文献
924.
Zsolt Kovács Árpád Dobolyi Gábor Juhász Katalin A. Kékesi 《Neurochemical research》2010,35(3):452-464
Nucleosides are neuromodulators that have a wide range of biological roles in the brain. In order to better understand the
function of nucleosides in the human central nervous system (CNS), we constructed a nucleoside map showing the concentration
of various nucleosides and their metabolites using post mortem samples from 61 human brain areas and 4 spinal cord areas.
We evaluated in vivo tissue levels of four nucleosides (uridine, inosine, guanosine, and adenosine) and three of their metabolites
(uracil, hypoxanthine, and xanthine). The concentrations of nucleosides were unevenly distributed across different brain regions,
where the highest levels were found in the cerebral cortex and basal ganglia, whereas the lowest concentrations were located
in the locus coeruleus, the zona incerta, the substantia nigra, and the inferior colliculus. The regional differences in nucleoside
levels in the CNS may reflect the distinct physiological functions adopted by these compounds in different brain areas. 相似文献
925.
Diwakar Aggarwal Anil Kumar M. Sudhakara Reddy 《Plant Cell, Tissue and Organ Culture》2010,102(1):45-52
An efficient shoot organogenesis system has been developed from mature plants of selected elite clones of Eucalyptus tereticornis Sm. Cultures were established using nodal explants taken from freshly coppice shoots cultured on Murashige and Skoog medium
containing 58 mM sucrose, 0.7% (w/v) agar (MS medium) and supplemented with 2.5 μM benzyladenine (BA) and 0.5 μM α-naphthaleneacetic
acid (NAA). Shoot organogenesis was achieved from leaf segments taken from elongated microshoots on MS medium supplemented
with 5.0 μM BA and 1.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D). The addition of cefotaxime to the medium promoted shoot
differentiation, whereas carbenicillin and cephalexin inhibited shoot differentiation. Maximum shoot bud organogenesis (44.6%)
occurred in explants cultured on MS medium supplemented with 5.0 μM BA, 1.0 μM 2,4-D and 500 mg/l cefotaxime. Leaf maturity
influenced shoot regeneration, with maximum shoot organogeneisis (40.5%) occurring when the source of explants was the fifth
leaf (14–16 days old) from the top of microshoot. Shoot organogenic potential also varied amongst the different clones of
E. tereticornis. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses indicated clonal uniformity of
the newly formed shoots/plants, and these were also found to be true-to-type. 相似文献
926.
Singapore is located near the equator, off the southern tip of the Malay Peninsula. The whole country consists mostly of lowland.
It has many interesting types of natural habitats such as primary rain forest, freshwater swamp forest, mangroves, secondary
forests, shrub, grasslands, and urban parks and fields. The climate is equatorial with relatively uniform temperature and
high humidity. Unfortunately, many of the natural habitats and the native orchids which thrive there have disappeared due
to habitat destruction. Some 226 species of native orchids have been recorded in Singapore. However, of these 178 are considered
to be extinct, and only five are common. The orchid conservation programme aims to monitor existing species, explore ways
to conserve their germplasm, and increase their numbers in natural, semi-natural, and urban environments through ex-situ seedling
culture and subsequent re-introduction into appropriate habitats, including roadside trees, parks and natural areas. In the
first phase of the programme, we have successfully propagated and carried out experiments of re-introduction on five species
of native orchids, namely, Grammatophyllum speciosum, Bulbophyllum vaginatum, Bulbophyllum membranaceum, Cymbidium finlaysonianum and Cymbidium bicolor. Survival percentages 8-yr after the reintroduction events ranged from 10 to 95 for G. speciosum, the target species of the earliest re-introduction experiments. Size of the seedlings at reintroduction, host trees, and
relative humidity seemed to play significant roles in the success rate of the reintroductions. 相似文献
927.
The European bitterling, Rhodeus amarus, is a non-indigenous fish species in British fresh waters. It lays its eggs in unionid mussels which themselves are vulnerable
to fouling by the non-indigenous zebra mussel, Dreissena polymorpha. Observations from an unmanipulated natural system showed that only 27% of zebra mussel-fouled Unio pictorum hosted bitterling, while 47% of unfouled U. pictorum hosted bitterling. We conducted a field experiment in the River Great Ouse catchment, Cambridgeshire, England in May–June
2007 and 2008 to quantify the impact of zebra mussels on bitterling load in host mussels. Zebra mussel-fouled unionids were
significantly less likely to host bitterling than unfouled unionids. The number of unionids hosting bitterling did not differ
significantly whether the zebra mussels fouling the unionid were alive or dead. Bitterling appeared to discriminate against
zebra mussel-fouled unionids less as the 2007 breeding season advanced, potentially because preferred unfouled unionids had
a higher bitterling load, and were therefore relatively lower quality hosts than at the start of the breeding season. 相似文献
928.
929.