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301.
In the central and peripheral nervous system of the crayfish, Orconectes limosus, neuropeptides immunoreactive to an antiserum against allatostatin I (= Dipstatin 7) of the cockroach Diploptera punctata have been detected by immunocytochemistry and a sensitive enzyme immunoassay. Abundant immunoreactivity occurs throughout the central nervous system in distinct interneurons and neurosecretory cells. The latter have terminals in well-known neurohemal organs, such as the sinus gland, the pericardial organs, and the perineural sheath of the ventral nerve cord. Nervous tissue extracts were separated by reverse-phase high-performance liquid chromatography and fractions were monitored in the enzyme immunoassay. Three of several immunopositive fractions have been purified and identified by mass spectroscopy and microsequencing as AGPYAFGL-NH2, SAGPYAFGL-NH2, and PRVYGFGL-NH2. The first peptide is identical to carcinustatin 8 previously identified in the crab Carcinus maenas. The others are novel and are designated orcostatin I and orcostatin II, respectively. All three peptides exert dramatic inhibitory effects on contractions of the crayfish hindgut. Carcinustatin 8 also inhibits induced contractions of the cockroach hindgut. Furthermore, this peptide reduces the cycle frequency of the pyloric rhythms generated by the stomatogastric nervous system of two decapod species in vitro. These crayfish allatostatin-like peptides are the first native crustacean peptides with demonstrated inhibitory actions on hindgut muscles and the pyloric rhythm of the stomatogastric ganglion.  相似文献   
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OBJECTIVE: To assess the effectiveness of a home exercise programme of strength and balance retraining exercises in reducing falls and injuries in elderly women. DESIGN: Randomised controlled trial of an individually tailored programme of physical therapy in the home (exercise group, n = 116) compared with the usual care and an equal number of social visits (control group, n = 117). SETTING: 17 general practices in Dunedin, New Zealand. SUBJECTS: Women aged 80 years and older living in the community and registered with a general practice in Dunedin. MAIN OUTCOME MEASURES: Number of falls and injuries related to falls and time between falls during one year of follow up; changes in muscle strength and balance measures after six months. RESULTS: After one year there were 152 falls in the control group and 88 falls in the exercise group. The mean (SD) rate of falls was lower in the exercise than the control group (0.87 (1.29) v 1.34 (1.93) falls per year respectively; difference 0.47; 95% confidence interval 0.04 to 0.90). The relative hazard for the first four falls in the exercise group compared with the control group was 0.68 (0.52 to 0.90). The relative hazard for a first fall with injury in the exercise group compared with the control group was 0.61 (0.39 to 0.97). After six months, balance had improved in the exercise group (difference between groups in change in balance score 0.43 (0.21 to 0.65). CONCLUSIONS: An individual programme of strength and balance retraining exercises improved physical function and was effective in reducing falls and injuries in women 80 years and older.  相似文献   
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Paul Buchner 《Zoomorphology》1933,26(4):709-777
Ohne Zusammenfassung  相似文献   
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Ohne ZusammenfassungAus der von der Deutschen Forschungsgemeinschaft eingerichteten, der Symbiose-Forschung dienenden Arbeitsstätte in Porto d'Ischia. Gewidmet ist die Studie dem Coccidenkenner A. Reyne, Amsterdam, welcher seit Jahren dem Verf. seine reiche Erfahrung zur Verfügung stellte, aber ihr Erscheinen nicht mehr erleben sollte.  相似文献   
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Journal of Plant Research - Under low-light conditions, chloroplasts localize along periclinal cell walls at temperatures near 20 °C, but they localize along anticlinal cell walls near...  相似文献   
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