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61.
Most of the available data on the cytoarchitecture of the cerebral cortex in mammals rely on Nissl, Golgi, and myelin stains and few studies have explored the differential morphologic and neurochemical phenotypes of neuronal populations. In addition, the majority of studies addressing the distribution and morphology of identified neuronal subtypes have been performed in common laboratory animals such as the rat, mouse, cat, and macaque monkey, as well as in postmortem analyses in humans. Several neuronal markers, such as neurotransmitters or structural proteins, display a restricted cellular distribution in the mammalian brain, and recently, certain cytoskeletal proteins and calcium-binding proteins have emerged as reliable markers for morphologically distinct subpopulations of neurons in a large number of mammalian species. In this article, we review the morphologic characteristics and distribution of three calcium-binding proteins, parvalbumin, calbindin, and calretinin, and of the neurofilament protein triplet, a component of the neuronal cytoskeleton, to provide an overview of the presence and cellular typology of these proteins in the neocortex of various mammalian taxa. Considering the remarkable diversity in gross morphological patterns and neuronal organization that occurred during the evolution of mammalian neocortex, the distribution of these neurochemical markers may help define taxon-specific patterns. In turn, such patterns can be used as reliable phylogenetic traits to assess the degree to which neurochemical specialization of neurons, as well as their regional and laminar distribution in the neocortex, represent derived or ancestral features, and differ in certain taxa from the laboratory species that are most commonly studied. 相似文献
62.
BACKGROUND/PURPOSE: Signal transduction via the epidermal growth factor receptor (EGFR) is critical for intestinal adaptation after massive small bowel resection (SBR). Although it has been assumed that the major ligand for the EGFR during adaptation is EGF, the role for transforming growth factor-alpha (TGF-alpha), another major ligand for the EGFR is unknown. The purpose of this study was to test the hypothesis that TGF-alpha is an important ligand for the EGFR during intestinal adaptation. METHODS: Wild-type mice (C57BI/6) underwent a 50% proximal SBR or sham operation (bowel transection or reanastomosis) and were then assigned randomly to receive either intraperitoneal TGF-alpha or placebo. In a separate experiment, SBR or sham operations were performed in mice lacking TGF-alpha (Waved-1). After 3 days, adaptation was measured in the ileum. RESULTS: Exogenous TGF-alpha enhanced intestinal adaptation in the wild-type mice after SBR as shown by increased ileal wet weight and DNA content. Normal adaptation occurred in the mice lacking TGF-alpha as shown by increased ileal wet weight, protein and DNA content, proliferation, villus height, and crypt depth. CONCLUSIONS: Although exogenous TGF-alpha enhanced adaptation after massive SBR, adaptation was preserved in TGF-alpha-absent mice. These results refute TGF-alpha as an essential ligand for EGFR signaling during intestinal adaptation. 相似文献
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64.
Sharon K Krueger Lisbeth K Siddens Sarah R Martin Zhen Yu Clifford B Pereira Erwin T Cabacungan Ronald N Hines Kristin G Ardlie Judy L Raucy David E Williams 《Drug metabolism and disposition》2004,32(12):1337-1340
A polymorphism for the phase I drug-metabolizing enzyme, flavin-containing monooxygenase isoform 2 (FMO2), encoding either truncated inactive protein, FMO2X472 (FMO2.2A), or full-length active enzyme, FMO2Q472 (FMO2.1), is known and exhibits significant interethnic differences in allelic frequency. FMO2 is the major or sole FMO isoform expressed in the lung of most mammals, including nonhuman primates. To date, FMO2.1 has been found only in African-American and Hispanic populations, rendering individuals with this allele subject to drug metabolism that is potentially different from that of the general population. Approximately 26% of African-Americans (n = 180) possess the FMO2*1 allele. In preliminary studies, we initially estimated that 5% of Hispanics (n = 40) have the FMO2*1 allele, but access to large cohorts of individuals of defined national origin has allowed us to determine the occurrence among Mexican-American and Puerto Rican-American groups. We used allele-specific genotyping to detect FMO2*1 from 632 Hispanic individuals, including 280 individuals of Mexican origin and 327 individuals of Puerto Rican origin. Statistical analysis indicated that results from Mexican (five sample sources) and Puerto Rican (three sample sources) samples were consistent with the hypothesis of homogeneity within each group from different sources. Data were subsequently pooled across sources to test for evidence of a difference in occurrence of FMO2*1 between ethnic groups. There was strong evidence (p = 0.0066) that FMO2*1 is more common among Puerto Ricans (7%) than among individuals of Mexican descent (2%). The overall occurrence of FMO2*1 among Hispanics of all origins is estimated to be between 2 and 7%. 相似文献
65.
Beu P. Oropeza Carlos Serna III Michael E. Furth Luis H. Solis Cesar E. Gonzalez Valeria Altamirano Daisy C. Alvarado Jesus A. Castor Jesus A. Cedeno Dante Chaparro Vega Octavio Cordova Isaac G. Deaguero Erwin I. Delgado Mario F. Garcia Duarte Mirsa Gonzalez Favela Alba J. Leyva Marquez Emilio S. Loera Gisela Lopez Fernanda Lugo Tania G. Miramontes Erik Munoz Paola A. Rodriguez Leila M. Subia Arahim A. Zuniga Herrera Thomas Boland 《Materials》2022,15(13)
The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues. 相似文献
66.
A 25-year-old woman had signs of an acute surgical abdomen. Differential diagnoses were ectopic pregnancy and acute appendicitis. Diagnostic laparoscopy revealed an apparent inflamed appendix and left-sided unruptured tubal ectopic pregnancy. This case illustrates the importance of considering multiple pathologic disorders in a patient with an acute surgical abdomen, especially in pregnancy. Furthermore, it shows that laparoscopy constitutes the optimal treatment modality in patients with multiple diagnoses, because it combines multifocal diagnosis and treatment without additional postoperative morbidity. 相似文献
67.
Adelekan AM Prozesky EA Hussein AA Ureña LD van Rooyen PH Liles DC Meyer JJ Rodríguez B 《Journal of natural products》2008,71(11):1919-1922
A new indanone derivative (1) and two new diterpenoids (2 and 3), together with three known flavonoids, have been isolated from an ethanol extract of the leaves of Croton steenkampianus. The structure of 2 was solved by single-crystal X-ray diffraction analysis, whereas those of 1 and 3 were established mainly by 1D and 2D NMR spectroscopic methods. The isolated compounds were tested for their antiplasmodial activity and cytotoxicity. Antiplasmodial assays against chloroquine-susceptible strains (D10 and D6) and the chloroquine-resistant strains (Dd2 and W2) of Plasmodium falciparum showed that compound 2 gave moderate activities at 9.1-15.8 μM, while none of the compounds were cytotoxic against Vero cells. 相似文献
68.
69.
Erwin Mölling 《Journal of molecular medicine (Berlin, Germany)》1938,17(45):1586-1586
Ohne Zusammenfassung 相似文献
70.
Assistent Erwin Dissmann 《Journal of cancer research and clinical oncology》1932,36(1):563-571
Zusammenfassung In dem Zeitraum von 1925–1931 haben unter den Sektionen des Deutschen Pathologischen Institutes in Prag die Lungen- und Bronchialcarcinome unter starken Schwankungen weiter zugenommen und im Jahre 1931 die bisher in Prag höchste Zahl von 16,47% der gesamten Carcinome erreicht. Unter 7855 Sektionen dieses Zeitraumes fanden sich 80 sichere Bronchial- und Lungenkrebse, was 1,02% aller Sektionen und 10,85% der gesamten Carcinome entspricht. Der Fünfjahrsdurchschnitt 1925–1929 zeigt ein weiteres Ansteigen gegenüber dem der Jahre 1920–1924.Das 6. Lebensjahrzehnt bleibt auch weiterhin das des häufigsten Vorkommens.Das Verhältnis der männlichen Bronchialcarcinome zu den weiblichen hat sich in den letzten 7 Jahren zugunsten der ersteren verschoben. Die männlichen Bronchialkrebse sind in diesem Zeitraume etwa 4 mal so häufig als die weiblichen, während sie bis zum Jahre 1924 nur doppelt so häufig waren.Sitz des Tumors und Metastasierung zeigen keine wesentlichen Abweichungen von den bisher in der Literatur festgestellten Verhältnissen.Bei einer großen Anzahl der an Lungenkrebs Verstorbenen ließ sich ein Beruf nachweisen, der Staub und Rauchwirkungen stärker als andere Berufe ausgesetzt war.Mehr als die Hälfte der Wohnorte der aus der Peripherie nach Prag gekommenen Lungencarcinome liegen im westlichen Böhmen.Mit 2 Textabbildungen. 相似文献