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1.
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity.  相似文献   
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A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
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Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.  相似文献   
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BACKGROUND: Although selective serotonin reuptake inhibitors (SSRIs) are the mainstay of pharmacological treatment for obsessive-compulsive disorder (OCD), some OCD patients do not show improvement. Sometimes, the addition of a low-dose atypical antipsychotic, such as risperidone, or olanzapine, to ongoing SSRI treatment has been shown to be effective. However, there are patients who still show no response after trials with this augmentation therapy. In the present study, we examined the clinical features of OCD patients who showed different responses to pharmacological treatment. SUBJECTS AND METHOD: Fifty OCD patients were divided into three groups according to their pharmacological responses: responders to SSRI (group A: n= 25), responders to SSRI with an atypical antipsychotic (group B: n= 15), and non-responders to both SSRI and SSRI with an atypical antipsychotic (group C: n= 10). We examined the clinical features such as age, sex, age of onset, duration of illness, types of obsessive-compulsive symptoms, severity, improvement after treatment, insight into disease, depression, comorbidity, involving family members in compulsive or ritualistic behavior, and the level of social adaptation of each OCD group. RESULTS: Twenty five patients showed a good response to SSRI monotherapy, 15 showed a response to antipsychotic augmentation, and 10 were non-responders to both SSRI and SSRI with an atypical antipsychotic. Significantly lower insight levels were observed only in group B and higher depressive levels in group C. OCD patients who were refractory to SSRI monotherapy showed comorbidity at a significantly higher frequency. OCD patients in group A showed significantly greater improvement, and group B showed inferior social adaptation after treatment. There were no significant differences in age, sex, age of onset, duration of illness, severity, involving family members in compulsive or ritualistic behavior, and social adaptation before treatment in the three OCD groups. CONCLUSION: There were differences in the clinical features of OCD patients who showed different responses to pharmacological treatment. Our results suggest that OCD is clinically and biologically heterogeneous. It may be important to divide OCD patients into subgroups for future studies.  相似文献   
7.
The effect of a nucleoside-nucleotide mixture on liver injury of rats induced by D-galactosamine was studied by examining changes in function and histopathology of the liver. Animals with liver damage received total parenteral nutrition with glucose and amino acids supplemented with a nucleoside-nucleotide mixture containing inosine, cytidine, GMP, uridine and thymidine, or with uridine which inhibits galactosamine injury, or with liver cell extract containing flavin adenine dinucleotide and nucleic acid derivatives. As control, animals with liver damage received total parenteral nutrition with glucose and amino acids only. The serum GOT and GPT concentrations were significantly lower in the group supplemented with nucleoside-nucleotide mixture than those in other groups. A large dose (1.2 g/kg) of uridine inhibited liver injury, but a lower dose (0.14 g/kg) did not have any effect, whereas nucleoside-nucleotide mixture containing the same amount of uridine inhibited the injury. Liver cell extract also did not improve liver function. Thus infusion of a physiological and balanced mixture of nucleosides or nucleotides may improve liver function in rats with liver injury.  相似文献   
8.
The acute onset of peritoneal signs and shock in a 7year-old boy who had been hit in the epigastrium by a log-seesaw mandated surgical treatment. Enhanced computed tomography (CT) demonstrated complete laceration of the pancreas as well as duodenal injury, and a duodenoduodenostomy with distal pancreaticogastrostomy was subsequently performed. Temporary external drainage of the stomach and distal pancreas led to an uneventful recovery in the early postoperative period. Although the patient's postoperative development was appropriate for his age, the orifice of the distal pancreas spontaneously closed 2.5 years following surgery. We present this report to stress the fact that every effort should be made to preserve the pancreas following abdominal injury in children.  相似文献   
9.
Recombinant human erythropoietin therapy and autonomic nervous system.   总被引:1,自引:0,他引:1  
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10.
The cell bodies of the sensory and sympathetic pre- and postganglionic neurons projecting into the cervical sympathetic trunk were retrogradely labeled with horseradish peroxidase in the chicken. Preganglionic neurons were located in the spinal segments T1-T6 (maximum T2), postganglionic neurons in the paravertebral ganglia T1-T3 (maximum T1) and sensory neurons in the dorsal root ganglia T1-T4 (maximum T1). Labeled preganglionic neurons were widely distributed across the intermediate gray matter and lateral funiculus, but the majority of them were located in the intermediomedial area dorsolateral to the central canal. The short and long axis diameters of labeled preganglionic neurons in this area decreased caudally. From the data of the present study, it is estimated that about 4190 preganglionic, about 450 postganglionic and about 390 sensory neurons project into the cervical sympathetic trunk cranial to the paravertebral ganglion T1 in the chicken.  相似文献   
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