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41.
Projection neurons in the rat dorsolateral septal nucleus (DLSN) were labeled intracellularly with horseradish peroxidase (HRP) in an in vitro slice preparation. The labeled neurons exhibited widespread 'isodendritic' type dendritic fields. Each of the neurons was identified as a projection neuron by the tracing of its main axon out of DLSN. The axons of these neurons gave rise to intrinsic collaterals which branched to form an extensive axon plexus which was confined to DLSN. These axon collaterals exhibited numerous en passant swellings suggestive of boutons. It is proposed that the recurrent axon collaterals of DLSN projection neurons may form an anatomical substrate for local inhibition within DLSN.  相似文献   
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Neuraminidases were purified from reassortant viruses (H6N1 and H6N2) containing the two antigenic subtypes (N1 and N2) found in human influenza viruses. Surface glycoproteins were solubilized with octylglucoside, and the neuraminidase was isolated by chromatography on DEAE-Sephadex. Neuraminidase isolated by this technique coeluted with viral lipids and spontaneously formed liposomes on dialysis. The purified neuraminidase was immunogenic in rabbits, producing a significant antibody response at dose levels as low as 1 microgram.  相似文献   
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A cultural effect on brain function   总被引:3,自引:0,他引:3  
We present behavioral and anatomical evidence for a multi-component reading system in which different components are differentially weighted depending on culture-specific demands of orthography. Italian orthography is consistent, enabling reliable conversion of graphemes to phonemes to yield correct pronunciation of the word. English orthography is inconsistent, complicating mapping of letters to word sounds. In behavioral studies, Italian students showed faster word and non-word reading than English students. In two PET studies, Italians showed greater activation in left superior temporal regions associated with phoneme processing. In contrast, English readers showed greater activations, particularly for non-words, in left posterior inferior temporal gyrus and anterior inferior frontal gyrus, areas associated with word retrieval during both reading and naming tasks.  相似文献   
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Interleukin-10 (IL-10) is an important immunoregulatory cytokine. The recent characterisation of the proximal 5' flanking region of IL-10 led to the identification of the promoter region. Two polymorphic dinucleotide repeats and 10 single nucleotide polymorphisms (SNPs) have been identified and suggested to be useful genetic markers in several diseases. We have sequenced a further 5275 bp from -9296 to -4021 of the distal part of the 5' flanking region of the human IL-10 gene from the cosmid clone pWE15-4/11. Our sequence analysis reveals a high density of Alu-repeats within the IL-10 gene locus, including three novel, related structures which we term Alu-IL10 (A-C). Using three overlapping PCR products spanning 5110 bp of this distal part of the IL-10 gene the following single base pair substitutions were identified: at -8571 C/T, -8531 G/A, -6752 A/T, -6208 G/C, -5402 C/G. In addition a heterozygous three base pair deletion at -7400 was observed. The SNPs at -8571 C/T and -8531 G/A are contained within an Alu-repeat. These data should further the understanding of how the IL-10 gene is controlled in man and how its function may vary between individuals.  相似文献   
48.
Superior vena cava (SVC) obstruction commonly occurs in the setting of malignancy. Cases of benign SVC obstruction are being seen more frequently with the use of long-term central venous lines. This is the case particularly in Cystic Fibrosis (CF). We describe in this report the successful use of intravascular stenting to treat this distressing condition in the setting of thrombotic occlusion of the SVC in a patient with CF.  相似文献   
49.
The effect of the absence of biliary and/or pancreatic secretions in the duodenum or the enhanced presence of bile at the proximal duodenum on the incidence, severity, number, and location of cysteamine-induced duodenal ulcers was investigated in the rat. Cysteamine produced ulcers on the anterior wall of the duodenum in 75% and on the posterior wall (kissing ulcers) in 50% of the animals. Diversion of biliary and/or pancreatic secretions from the duodenum increased both the severity and the incidence of the posterior duodenal ulcers. Diversion of bile to the proximal duodenum, on the other hand, decreased the severity as well as the incidence of the anterior duodenal ulcers. Mortality in rats receiving cysteamine correlated with the severity of ulcers. Taurocholic acid at nontoxic doses given subcutaneously or orally to nonoperated rats and rats which had bile diverted to the proximal duodenum aggravated the cysteamine-caused duodenal ulcers. Neither proximal nor distal diversion of bile had a major effect on gastric secretion of acid and pepsin in normal or cysteamine-treated rats. We conclude that both bile and pancreatic secretions may directly influence the development of cysteamine-induced duodenal ulcers in the rat.These studies were supported in part by a grant (AM25229) and Research Career Development Award (AM00600) to S. Szabo from NIH and U.S. Public Health Service.  相似文献   
50.
Sixty-three (5%) of 1239 women studied by sonography during the second trimester of their pregnancies had a diagnosis of placenta previa. Follow-up was available for 51 of the 63 patients; in three of these, the original diagnosis was complete placenta previa, and in the other 48, the first diagnosis was partial or marginal placenta previa. At term, placenta previa was seen in only four patients for an overall frequency of 0.3% (4/1227). In all three of the patients with complete placenta previa, the condition persisted from the second trimester to term; previa persisted in only one of 48 patients with marginal/partial previa. Because of the infrequent persistence of marginal or partial placenta previa to term, we recommend using the term "potential placenta previa" in the second trimester, with follow-up sonography indicated only for vaginal bleeding.  相似文献   
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