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1.
Amphibian terminal nerve: distribution revealed by LHRH and AChE markers   总被引:2,自引:0,他引:2  
Immunocytochemical and histochemical studies in the tiger salamander and bullfrog demonstrated the presence of luteinizing hormone-releasing hormone-like immunoreactive (LHRH-ir) material and acetylcholinesterase (AChE) in the terminal nerve (TN). Immunoreactive perikarya and processes were found within the olfactory, vomeronasal and trigeminal nerves and in the nasal epithelium. Central TN projections consisted of fibers terminating in the olfactory bulb and bundles that projected to another group of LHRH-ir perikarya in the preoptic region. Up to 4 weeks following hypophysectomy, the labeling intensity and number of TN-immunoreactive neurons were not altered. Acetylcholinesterase histochemistry in the salamander revealed two distinct groups of neurons associated with the TN: a lightly labeled group of fusiform perikarya was located in the olfactory nerve proper and a more heavily labeled group of larger oval perikarya was found within AChE-positive trigeminal fascicles in the ventral mucosa. This study has demonstrated that the amphibian TN follows olfactory, vomeronasal and trigeminal nerves to reach peripheral targets in the nasal mucosa. The projection of TN fibers to discrete olfactory bulb glomeruli, especially evident in the bullfrog, suggests that the TN functions in odor processing. The TN projection to the preoptic region in both of these amphibians implicates the TN in reproductive processes.  相似文献   
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We studied patients with transfusion-associated acquired immunodeficiency syndrome (AIDS) and their blood donors for serologic evidence of infection with human T-cell lymphotropic virus type III/lymphadenopathy-associated virus with two enzyme-linked immunosorbent assays and a Western blot assay. All 19 patients with AIDS were seropositive by at least one test. In all 28 donor sets containing "high-risk" donors, at least one donor was seropositive by one or more tests. Of 255 donors not considered high risk, two (0.8%) were seropositive by all three tests. When 30 seropositive high-risk donors were evaluated a median of 29 months after donation, four (13%) had developed AIDS and eight (27%) had lymphadenopathy. Our findings support the hypothesis that human T-cell lymphotropic virus type III/lymphadenopathy-associated virus causes AIDS and indicate that seropositive high-risk donors may be at relatively high risk for developing AIDS or related conditions themselves.  相似文献   
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The intrauterine environment during pregnancy is a critical factor in the development of diabetes and obesity in offspring. To determine the effects of maternal exercise during pregnancy on the metabolic health of offspring, 6-week-old C57BL/6 virgin female mice were fed a chow (21%) or high-fat (60%) diet and divided into four subgroups: trained (housed with running wheels for 2 weeks preconception and during gestation), prepregnancy trained (housed with running wheels for 2 weeks preconception), gestation trained (housed with running wheels during gestation), or sedentary (static cages). Male offspring were chow fed, sedentary, and studied at 8, 12, 24, 36, and 52 weeks of age. Offspring from chow-fed dams that trained both before and during gestation had improved glucose tolerance beginning at 8 weeks of age and continuing throughout the 1st year of life, and at 52 weeks of age had significantly lower serum insulin concentrations and percent body fat compared with all other groups. High-fat feeding of sedentary dams resulted in impaired glucose tolerance, increased serum insulin concentrations, and increased percent body fat in offspring. Remarkably, maternal exercise before and during gestation ameliorated the detrimental effect of a maternal high-fat diet on the metabolic profile of offspring. Exercise before and during pregnancy may be a critical component for combating the increasing rates of diabetes and obesity.  相似文献   
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肿瘤相关基因Cap43在胰腺癌中的表达及意义   总被引:4,自引:0,他引:4  
目的研究肿瘤相关基因Cap43在胰腺癌组织中的表达情况,探讨其对胰腺癌的诊断价值。方法收集1999年4月~2002年8月长海医院外科手术切除胰腺癌标本和癌旁正常组织33例,诊断均由病理证实。男性22例,女性11例,年龄30~73岁,平均58.1岁。所有组织标本按肿瘤、癌旁(正常)配对。采用RT-PCR和Northern杂交方法研究Cap43 mRNA表达情况。结果 RT-PCR结果显示,Cap43在肿瘤组织中表达显著上调,其在肿瘤组织和癌旁正常组织的扫描值分别为4 033±1 986和2 244±1 145,有显著差异(P<0.001)。Northern杂交亦显示Cap43在肿瘤组织中表达显著上调,相同病例的RT-PCR结果与Northern杂交的结果有较好的一致性,经回归分析,没有显著性差异(P>0.1)。结论 Cap43在胰腺癌组织中呈显著高表达,其有可能成为胰腺癌早期诊断的重要标志物。  相似文献   
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T V Getchell 《Brain research》1977,123(2):275-286
Intracellular recordings have been obtained from provisionally identified olfactory receptor and sustentacular cells in the salamander olfactory epithelium. Two categories of membrane potential transients were recorded intracellularly in response to odor stimulation. The first category of responses, presumably recorded from receptor cell somas, were monophasis positive spikes 10-50 mV in amplitude which were superimposed on a depolarizing slow potential which ranged from 4 to 8 mV in amplitude. Graded and differential responses were recorded in response to odor stimulation. The second category of responses were depolarizing and hyperpolarizing slow membrane potential transients presumably recorded from sustentacular cells. Spiking was not observed in response to odor stimulation. Pysiological criteria and Procion dye marking in several instances have provided evidence that responses in the first category were recorded from olfactory receptors and that certain of the other responses were recorded from sustentacular cells.  相似文献   
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Neurogenesis in the olfactory epithelium (OE) is induced by olfactory bulbectomy (OBX), which effectively axotomizes olfactory sensory neurons (OSNs) and removes their synaptic targets, resulting in apoptosis. We used Affymetrix high-density oligonucleotide arrays to investigate changes in gene expression during initiation of signaling in pathways that regulate apoptosis and neurogenesis in the murine OE at 2, 8, 16, and 48 hr after bilateral OBX compared to that in sham-operated controls. We focused on regulation of a defined set of genes associated with apoptosis, stem/progenitor cell regulation, and cell cycle progression because of the activation of these processes in OE degeneration and remodeling after OBX. After data scrubbing and categorical analysis, one-way analysis of variance identified 72 genes (4.9% of the present known genes) as being regulated significantly (P < 0.05) at one or more points; 50 were defined as regulated differentially with the false discovery rate at 10%. Significant changes in gene expression occurred in all categories as early as 2 hr post-OBX, with the greatest number of differentially regulated genes at 16 and 48 hr. Hierarchical cluster analysis and correlation coefficients were used to identify similarities in patterns of gene expression changes within and across categories. Validation was carried out with SuperArray macroarrays and real-time RT-PCR. Our results confirmed the participation of many genes in known signaling pathways and identified changes in the expression of 42 genes not identified previously as participating in apoptosis and neurogenesis in the OE. Additionally, our analyses indicated the early involvement of genes regulating cytoskeletal reorganization and angiogenesis in the response to OBX. These studies are an important first step in defining early time-dependent changes in gene expression after target ablation that lead to neurogenesis in the olfactory sensory epithelium.  相似文献   
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Intussusception in adults is a rare cause of abdominal pain. Unlike its paediatric counterpart, intussusception in adults is associated with obvious pathology. We describe a case of ileocolic intussusception extending to the splenic flexure. We were able to reduce the intussusception partially and pedicle was stapled carefully. The specimen was delivered through a small incision and right hemicolectomy was performed adhering to oncological principles. We recommend laparoscopic-assisted surgery is considered for adult intussusceptions.  相似文献   
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