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341.
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Ophioglossum yongrenense Ching ex Z. R. He et W. M. Chu, sp. nov.Species nova aspectu inter O. kawamuram Tagawa et O. parvum Nishida et Kurita Japonicae, differt a priore frondibus pro parte laminis sterilibus praeditis (in illa frondibus omnino laminis sterilibus non praeditis), a posteriore frondibus pro parte laminis sterilibus non praeditis (in O. parvo Nishida et Kurita frondibus omino laminis sterilibus praeditis).……  相似文献   
343.
  • The taxonomic importance of macromorphological and micromorphological seed characteristics was investigated using SEM of ten species of the Salvia genus from Pakistan. The aim was to identify diagnostic seed ultrastructural features that could aid in species delimitation, correct identification and phylogenetic position. The ultrastructure of Salvia varies greatly, and a wide range of unique micromorphological features have been observed.
  • Seed micromorphological features were explored by SEM, including seed shape, colour, texture, cell outline, surface sculpturing, epidermal cell arrangement, anticlinal, and periclinal wall pattern.
  • Seed shapes were categorized as obovate, spherical, spheroid, broadly elliptic, elliptic and oblong, mostly with a terminal hilum. Seed colours were black, light brown, dark brown, brown and yellow. Exo-morphological characters, i.e. epidermal cell arrangements, included irregular, wavy pentagonal-hexagonal, regular pentagonal-hexagonal. Cluster analysis was used to assess similar and distinct species within Salvia with a feasible explanation. Taxonomic keys were made based on micromorphological qualitative features that help to delimit species and identify them quickly within the Salvia genus.
  • Seed morphology of ten Salvia species was described and investigated, and the diagnostic significance of features evaluated using SEM. This study analysed seed features, especially at the species level, which might provide much new taxonomic information. The results revealed that, in seed morphology, using SEM can help with taxon identification, especially at the genus and species levels.
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344.
The present study was conducted primarily to determine the occurrence of polypharmacy in patients with schizophrenia on risperidone. The secondary aim was to ascertain the incidence of inappropriate prescribing with anticholinergics. A retrospective review of the medical records of all patients who were being followed up at the out-patient clinic of a tertiary-care hospital in Malaysia was conducted. Only patients who were being prescribed risperidone between 1 June 2008 and 31 December 2008 were included in the study. Demographic data such as patient’s age, gender and race were obtained from the patient’s medical records. In total, 113 patients met the selection criteria. Polypharmacy was found to occur in 34 patients (30.09%), with the majority (76.47%) being on two antipsychotics. In total, 27 patients (34.18%) on monotherapy with risperidone were prescribed an anticholinergic on scheduled dosing, while 19 patients (24.05%) were prescribed it on an as-needed basis. Of the patients on polypharmacy, 26 (76.47%) were on scheduled dosing of anticholinergics, while three (8.82%) were taking the medication on an as-needed basis. Polypharmacy should be avoided, and the use of anticholinergics should be closely reviewed. By adopting more efficient prescribing practices, costs can be reduced and financial resources can instead be channelled towards more beneficial areas for the patients.  相似文献   
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The freshwater leech, Hirudo medicinalis, is a versatile model organism that has been used to address scientific questions in the fields of neurophysiology, neuroethology, and developmental biology. The goal of this report is to consolidate experimental techniques from the leech system into a single article that will be of use to physiologists with expertise in other nervous system preparations, or to biology students with little or no electrophysiology experience. We demonstrate how to dissect the leech for recording intracellularly from identified neural circuits in the ganglion. Next we show how individual cells of known function can be removed from the ganglion to be cultured in a Petri dish, and how to record from those neurons in culture. Then we demonstrate how to prepare a patch of innervated skin to be used for mapping sensory or motor fields. These leech preparations are still widely used to address basic electrical properties of neural networks, behavior, synaptogenesis, and development. They are also an appropriate training module for neuroscience or physiology teaching laboratories.  相似文献   
347.
11 cases of spontaneous pituitary neoplasms in rats, which showed infiltration into brain tissue, are reported. This represents an incidence of about 0.42%.  相似文献   
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Excised roots of corn, 8 cm long, were mounted for collection of xylem exudate, submerged in aerated, labeled salt solutions, and left while steady-state exudation developed. After 19 hr, additional portions of the roots were removed and all apical ends which had been severed were sealed with wax. Collection of exudate samples began 1 hr later and continued for 8 hr. The results showed that removal of only 1 cm from the apex of the root reduced the output of rubidium to the exudate by as much as 74%. They also showed that the longitudinal changes in ion contribution to the exudate were not linear, but were closely correlated with the longitudinal gradient of Rb content in the root.  相似文献   
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