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Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
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5.
Inbred mice show strain-specific differences in the hippocampal mossy fiber projection. These differences are most pronounced in the portion of the projection that forms synaptic connections with the basal dendrites of the CA3 pyramidal neurons [intra- and infrapyramidal mossy fiber (IIP-MF) projection]. We have previously demonstrated that the extent of the IIP-MF subfield is positively correlated with the capacity to perform a spatial radial-maze task and that an experimentally induced enlargement of the IIP-MFs, by means of postnatal thyroxine treatment, predicted the ability of adult two-way avoidance learning. In the present study, we tested whether this treatment would also influence radial-maze performance. Forty-five male mouse pups from the inbred strain DBA/2 (chosen because of scanty IIP-MF projection and poor radial-maze learning) were divided into three groups that received daily injections of either 2 micrograms L-thyroxine, an alkaline vehicle solution, or physiological saline. Treatment lasted from postnatal days 0 to 11. At the age of 3 months, these animals were tested in an eight-arm radial maze. The extent of their IIP-MF projections was measured by means of planimetry on Timm-stained sections. Thyroxine-treated animals made significantly fewer errors and had larger IIP-MF projections as compared to both control groups. Within each group, the individual variability of the IIP-MF projection was significantly and positively correlated with performance. We conclude that experimentally modified IIP-MF projections mediate processes underlying spatial working memory. It would appear that the hippocampal circuitry alterations induced by postnatal hyperthyroidism can counteract a hereditary lack of talent, albeit only partially and in selected populations.  相似文献   
6.
The postnatal development of the hippocampus of the inbred mice strains BALB/c, C57BL/6, and DBA/2 was studied in organotypic explant cultures using the roller-tube technique. In vivo, mice exhibit strain-specific mossy fiber distribution patterns. As a main result we found, that after cultivation of 3-4 weeks, similar strain-specific patterns became apparent in vitro, as visualized by a modified Timm staining. From this experiment we can conclude that a postnatal extrinsic influence cannot be the cause of the strain-specific hippocampal features.  相似文献   
7.
OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
8.
Okamoto  S; Olson  AC; Berdel  WE; Vogler  WR 《Blood》1988,72(5):1777-1783
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.  相似文献   
9.
目的探讨完全腹腔镜Roux.en—Y吻合术式应用于远端胃癌根治术的安全性和可行性。方法回顾性分析福建省肿瘤医院腹部外科2012年8月至2013年3月对腹腔镜胃大部切除术后实施完全腹腔镜Roux.en—Y吻合术的20例胃癌患者的术中和术后临床资料。结果20例患者均成功实施完全腹腔镜远端胃癌根治术,无一例中转开腹或中转腹腔镜辅助手术。手术时间(190.8±53.6)min,术中出血量(122.4±57.7)ml,淋巴结清扫数(31.2±5.7)枚,术后病理切缘均为阴性。术后排气时间为(2.6±1.6)d,住院时间为(8.1±2.0)d。有1例术后出现肺部感染,但无吻合术相关并发症发生。结论完全腹腔镜Roux—en—Y吻合术式应用于远端胃癌根治术安全且可行。  相似文献   
10.
Mineur YS  Belzung C  Crusio WE 《Neuroscience》2007,150(2):251-259
Numerous data from human and animal studies suggest that hippocampal plasticity might be a key element in depression. However, the connection remains loose at best and further data are needed. Human studies are of necessity limited, but animal models can help providing further insight. Unpredictable chronic mild stress (UCMS) is a commonly used model because it mimics depression-like phenotypes satisfactorily. Its rationale is based on the underlying stress-induced difficulties found in many depressed patients. We therefore studied learning and hippocampal neurogenesis in mice from three different inbred strains subjected to UCMS. Learning was assessed in different hippocampus-dependent and independent tasks. The rate of survival of newly generated brain cells was determined in behaviorally-naive animals. Results demonstrated a dramatic reduction of surviving new brain cells in both the hippocampus and the subventricular zone of UCMS-treated animals. This reduction was observed both for neurons and for other cells of the hippocampus. Behavioral data demonstrated an impairment of hippocampus-dependent learning, whereas hippocampus-independent learning was spared. However, the specific results were strongly dependent on strain and sex so that there does not appear to be a direct causative relationship between the deficits in neurogenesis and behavior.  相似文献   
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