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1.
Early patterning of prelimbic cortical axons to the striatal patch compartment in the neonatal mouse
LK Nisenbaum SM Webster SL Chang KD McQueeney JJ LoTurco 《Canadian Metallurgical Quarterly》1998,20(2-3):113-124
The striatum receives excitatory input from virtually the entire cerebral cortex. In the adult, this input is segregated into two functionally distinct compartments of the striatum, the patch (striosome) and matrix regions. This study determined whether the patterning of corticostriatal afferents from the prelimbic cortex to the striatal patch compartment develops during the early period of collateral formation or instead at the time of peak synaptogenesis. Initial formation of corticostriatal axon collaterals was observed by embryonic day (E) 19. Quantification of corticostriatal collaterals revealed a significant increase in the number and complexity of collateral branches at postnatal day 6 as compared to E19. Concomitant with the increase in collateral branching, a heterogeneous pattern of collateralization consisting of parallel rows of corticostriatal collaterals was observed in the medial striatum. In addition to the rows, clusters of corticostriatal axons occurred more laterally. These clusters colocalized with patches of dense tyrosine hydroxylase-positive fibers, a marker for the striatal patch compartment in the neonatal mouse. Together, these data indicate that corticostriatal patterning occurs during the period of early axon collateralization resulting in a segregation of corticostriatal axon collaterals from the prelimbic cortex to the striatal patch compartment. 相似文献
2.
A Notghi R Hutchinson D Kumar NB Smith LK Harding 《Canadian Metallurgical Quarterly》1994,35(7):976-981
Segmental colonic transit has been measured in 101 patients. Two MBq of 111Indium absorbed on resin pellets and encapsulated in an enteric coated capsule was given at 7 00 am. Hourly images during the first day, and three images during each subsequent day were acquired for up to three days. Using all scan and patient data the scans were categorised in one of the five patterns of colonic transit: normal, rapid, right delay, left delay, or generalised delay. The geometric centres and per cent activity at each time point was compared between the five groups of colonic transit patients to find the best time for imaging and so to distinguish the five groups. During the first day, early images did not help in diagnosis of patterns of transit, however, in the later images (six hours onwards after the ingestion of the activity) the rapid transit groups could be identified. Images at 27 and 51 hours were both required to distinguish all five groups of patients from each other. Only in the 'normal' transit patients was there some excretion of the activity during the course of the second day, otherwise there was no difference in the images taken in the course of a day (second or third day). A simplified protocol requires a minimum of three images to distinguish all five patterns of colonic transit. The activity should be ingested in the morning (7 00 am) and the first image taken at the end of the working day (8-10 hours after ingestion), the second image on the morning of the second day, and the third image during the course of the third day. This simple protocol would provide all the clinically relevant information necessary for correct classification of the colonic transit. 相似文献
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A study was designed to test 2 alternative hypotheses--a symbolic hypothesis and an executive function hypotheses--for the imitation and pantomime deficits found in previous studies of autism. The subjects were 17 adolescent high-functioning subjects with autism spectrum disorders and 15 clinical comparison subjects who were matched on chronological age and verbal IQ. Meaning and sequence were manipulated in facial and manual imitation tasks. Sequence was manipulated in the pantomime and control tasks. Recognition memory and motor control tasks were matched to the experimental tasks. The results provided no support for the symbolic deficit hypothesis; meaning aided rather than hindered the performance of the group with autism. Partial support for the executive deficit hypothesis was found. There were no group differences on motor control tasks, and few on the memory control tasks, arguing against deficits in motor initiation, basic motor coordination, or visual recognition memory. 相似文献
6.
Prednisolone therapy of idiopathic feline lower urinary tract disease: a double-blind clinical study
CA Osborne JM Kruger JP Lulich GR Johnston DJ Polzin LK Ulrich J Sanna 《Canadian Metallurgical Quarterly》1996,26(3):563-569
A double-blind clinical study was performed to evaluate prednisolone as treatment for idiopathic feline lower urinary tract disease. No differences in response were observed in prednisolone- and placebo-treated cats. 相似文献
7.
T Tkebuchava LK von Segesser A Gallino O Dirsch MI Turina 《Canadian Metallurgical Quarterly》1997,38(3):457-462
1. The effect of the aqueous extract of Cissus sicyoides (CS) on isolated guinea pig aortic rings was studied. CS contracts the smooth muscle of the aorta in a dose-response relation. 2. The extract of CS increases the norepinephrine contraction in normal calcium and in solutions without calcium. 3. Lanthanum inhibits the contraction induced by CS. 4. The vasoconstrictor effect of CS was increased in solutions without calcium or with low calcium, which is an inverse calcium-dependent contraction. 5. Prolonged exposure to calcium-free solution did not abolish CS contraction. These contractions can be elicited repeatedly even after 6 hr of continuous exposure to calcium-free solutions. 6. Caffeine reduces contractile response induced by CS in normal calcium, as well as in solutions without calcium. 7. Our results support the idea that the aqueous extract of CS acts at the membrane level, increasing the calcium entry through the membrane as well as acting on the internal calcium deposits, possibly on the sarcoplasmic reticulum. 相似文献
8.
McEvoy Cathy L.; Nelson Douglas L.; Holley Patricia E.; Stelnicki Glennda S. 《Canadian Metallurgical Quarterly》1992,7(3):401
Reports 2 cued recall experiments in which younger and older Ss studied target words varying in number of preexperimental associates. In Exp 1, targets were studied in either the absence or presence of meaning-related context cues, with recall always prompted by the cues. In the absence of context, words with smaller sets of associates were easier to recall than those with larger sets, but this effect was reduced for older Ss. The presence of a study context cue facilitated recall and eliminated the effect of associative set size for both ages. In Exp 2, targets were studied and tested in the presence of unrelated words. In this situation, words with smaller sets of associates were less likely to be recalled than words with larger sets; again the effect was reduced for older Ss. The results are interpreted as an age decrement in processing implicitly activated information. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Only 19 cases of metastases at the cannula insertion site after laparoscopy for gynecological malignancy have been reported in the literature. One case has been diagnosed with cervical squamous cell carcinoma, whereas the others have been diagnosed with ovarian cancer and borderline ovarian tumor. We present a novel case of laparoscopy-site abdominal wall metastasis from endometrial cancer after laparoscopic-assisted vaginal hysterectomy (LAVH). The 56-year-old female patient exhibited metastases of an abdominal wall trocar site and a perineal site after undergoing LAVH and laparoscopic-assisted (LA) bilateral pelvic lymph node sampling as well as LA para-aortic lymph node sampling for treating endometrial carcinoma, surgical staging IIIC, G3. The interval between the surgical extirpation of endometrial carcinoma and diagnosis of the tumor recurrence was 6 months, suggesting that overmanipulation of the diseased organ during laparoscopic surgery may have resulted in tumor spillage, intraperitoneal dissemination, and wound contamination. Although this procedure has been proven beneficial to patients with benign disease or early-stage gynecologic malignancies, laparoscopic-assisted vaginal hysterectomy may not be efficacious to eradicate advanced gynecological malignancy. 相似文献
10.
CL Franklin CS Beckwith RS Livingston LK Riley SV Gibson CL Besch-Williford RR Hook 《Canadian Metallurgical Quarterly》1996,34(12):2952-2958
A filamentous, gram-negative, motile bacterium with a single polar sheathed flagellum was isolated from gallbladders of hamsters with cholangiofibrosis and centrilobular pancreatitis. Bacteria grew under microaerophilic conditions at 37 and 42 degrees C, were oxidase, catalase, arginine aminopeptidase, and L-arginine arylamidase positive, reduced nitrate to nitrite, were resistant to cephalothin, and exhibited intermediate susceptibility to nalidixic acid. Sequence analysis of the 16S rRNA gene indicated that the bacterium was a novel member of the Helicobacter genus, most closely related to Helicobacter pametensis. We propose to name this bacterium Helicobacter cholecystus. In epidemiologic studies, isolation of H. cholecystus correlated strongly with the presence of cholangiofibrosis and centrilobular pancreatitis; however, further studies are needed to define the role of this bacterium in pathogenesis. 相似文献