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排序方式: 共有994条查询结果,搜索用时 15 毫秒
41.
Efrem dvila Ferreira Mariko Hatta Yasunaga Takeda Chika Horikawa Mizuki Takeuchi Noriko Kato Hiroki Yokoyama Yoshio Kurihara Koichi Iwasaki Kazuya Fujihara Hiroshi Maegawa Hirohito Sone 《Nutrients》2022,14(1)
We aimed to analyze the association between dietary iron intake and obesity assessed by BMI after adjustment for nutrient intake (macronutrients and fiber) and food groups. The study design was cross-sectional. Patients with type-2 diabetes (n = 1567; 63.1% males; mean age 62.3 ± 11.6 years) were included in the study. To assess diet, consumption of typical food groups was determined by a food frequency questionnaire. Obesity was defined as BMI ≥ 25 kg/m2. We performed a binary regression analysis between quartiles of iron intake and obesity by quartiles of age group. A direct linear association was found for the highest quartile of iron intake and obesity in the younger age group of 30 to 54 years (OR = 3.641, 95% CI = 1.020–12.990; p trend = 0.011). Multivariate analysis using food groups as opposed to nutrients revealed a positive trend for obesity in the younger age group after adjusting for lifestyle factors, energy intake and bean and vegetable intake (p trend = 0.023). In all participants, an inverse association was observed before adjustment by vegetable intake (OR = 0.453, 95% CI = 0.300–0.684; p trend = 0.001). Higher iron intake was associated with obesity independent of macronutrient and fiber intake but only in the youngest quartile of age group examined. 相似文献
42.
Yuko Fujihara DDS ; Hiroyuki Koyama MD PhD ; Makoto Ohba PhD ; Yasuhiko Tabata DMS PharmD PhD ; Hisako Fujihara DDS PhD ; Yoshiyuki Yonehara MD PhD ; Tsuyoshi Takato MD PhD 《Wound repair and regeneration》2008,16(1):125-131
Therapeutic angiogenesis is a promising approach to treat ischemic skin flaps. We delivered basic fibroblast growth factor (bFGF) to the recipient bed of a rat dorsal skin flap by a drug delivery system with acidic gelatin hydrogel microspheres (AGHMs), and assessed augmentation of neovascularization and flap viability. An axial skin flap was elevated on the back of male Sprague–Dawley rats, and bFGF solution or bFGF-impregnated AGHMs were injected into the recipient bed. The dose of bFGF in the bFGF solution was set to 15 (Sol-15 group), 50 (Sol-50 group), or 150 μg (Sol-150 group). Correspondingly, 2 mg AGHMs were impregnated with 15 (AGHM-15 group), 50 (AGHM-50 group), or 150 μg (AGHM-150 group) bFGF. Other groups of animals received phosphate-buffered saline (Sol-Cont group) or phosphate-buffered saline-impregnated AGHMs (AGHM-Cont group) as controls. Seven days later, analyses of the area of necrosis, microangiographic findings, and histological findings in the flap were carried out. The area of necrosis in the AGHM-150 group was significantly smaller than that in the other groups. Microangiographic and histological analyses showed that neovascularization of the ischemic skin flap significantly increased in the AGHM-150 group as compared with the Sol-150 group and the AGHM-Cont group. These findings suggest that continuous delivery of bFGF to the recipient bed by bFGF-impregnated AGHMs enhances the viability of an ischemic skin flap. 相似文献
43.
We describe a novel, high-resolution and noninvasive method for measuring tear volume changes in cats. The method entails photographing at the lid margin the tear meniscus area defined by instillation of 0.1% fluorescein solution into the cul-de-sac. The inferior tear meniscus area was obtained from the digitized images with computer-assisted software. The tear meniscus area increased in proportion to the saline volume applied into the conjunctival sac, which validates the technique. Furthermore, this technique detected with high sensitivity previously described increases in tear fluid secretion induced by the P2Y(2) agonist. We demonstrate in cats that changes in conjunctival sac tear volume can be evaluated by measurement of its inferior tear meniscus area. 相似文献
44.
45.
Ischemic preconditioning is capable of inducing mitochondrial tolerance in the rat brain 总被引:14,自引:0,他引:14
BACKGROUND: Preconditioning to ischemia is a phenomenon whereby a brief episode of sublethal ischemia and other nonlethal stressors produce protection against a subsequent detrimental ischemic insult. As mitochondrial dysfunction is related to necrotic and apoptotic neuronal death after cerebral ischemia, the authors examined if ischemic preconditioning is capable of inducing mitochondrial tolerance. METHODS: Forebrain ischemia was induced by bilateral common carotid artery occlusion with simultaneous hypotension for 8 min in Wistar rats (275-300 g). A 3-min ischemic episode performed 48 h before the 8-min ischemia was used for preconditioning. The extents of hippocampal CA1 neuronal damage were evaluated 7 days after reperfusion by neuro-specific nuclear protein immunostaining. Brain mitochondria were isolated 48 h after animals were subjected to the sham operation or the 3-min conditioning ischemia. Loss of cytochrome c from mitochondria after cerebral ischemia in vivo and after exposure of brain mitochondria to calcium in vitro was used as an indication of mitochondrial dysfunction. RESULTS: Results showed that ischemic preconditioning induced by a 3-min ischemic episode dramatically reduced the loss of hippocampal CA1 neurons resulting from a subsequent 8-min ischemia 7 days after reperfusion, and this protection was associated with a preservation of mitochondrial cytochrome c as examined after early reperfusion. Exposure of isolated brain mitochondria to calcium produced a dose-dependent increase in cytochrome c release either at 30 degrees C or at 37 degrees C. Compared with those animals receiving only sham operation, cytochrome c release caused by 100 microm calcium was significantly reduced in conditioned animals. CONCLUSION: Regarding the importance of mitochondrial dysfunction in mediating ischemic neuronal death, the above results indicate that mitochondria may serve as end-effecting organelles to ischemic preconditioning. 相似文献
46.
Qi S Zhan RZ Wu C Fujihara H Taga K Shimoji K 《Anesthesia and analgesia》2002,94(3):655-60; table of contents
Cellular swelling has been implicated as an early process after cerebral ischemia. We compared the effects of two commonly used IV anesthetics, thiopental and propofol, on hippocampal CA1 pyramidal cell swelling induced by oxygen/glucose deprivation (OGD) in vitro. Experiments were performed in rat hippocampal slices. Cell swelling in the CA1 pyramidal cell layer was evaluated by determining light transmittance (LT) change through the slices and by histopathological examination. For LT experiments, OGD was induced for 10 min by superfusing slices with glucose-free artificial cerebrospinal fluid equilibrated with 95% nitrogen and 5% CO(2). Thiopental and propofol were present 10 min before and during the period of OGD. The results showed that thiopental (100 and 400 microM), but not propofol (40 and 160 microM), significantly prolonged latency to the peak of LT increase after the onset of OGD. Consistent with the LT experiments, histopathological examination revealed that thiopental, but not propofol, attenuated CA1 pyramidal cell expansion and the gap diminution between CA1 pyramidal cells induced by OGD. These results suggest that thiopental, but not propofol, reduces the neuronal cell swelling caused by OGD. Whether the reduction of cell swelling is related to reduction in cell injury caused by OGD remains to be investigated. IMPLICATIONS: We demonstrated that thiopental, but not propofol, attenuates ischemic neuronal swelling induced by oxygen/glucose deprivation in an in vitro ischemic model. 相似文献
47.
Fujihara A Kimura Y Mikami K Uchida M Tatebe A 《Hinyokika kiyo. Acta urologica Japonica》2002,48(10):607-610
A 65-year-old woman was referred to our clinic with gross hematuria. Cystoscopy revealed a non-papillary and non-pedunculated tumor on the left lateral wall of the bladder. A piece of necrotic tissue obtained from the bladder irrigation was histologically squamous cell carcinoma. A perforation at the left lateral wall of the bladder was found on the cystogram. Bone scintigraphy showed multiple metastases and computed tomography scans showed multiple lymph node metastases in the pelvic cavity. The clinical diagnosis was bladder carcinoma of T4N2M1 stage with an abscess due to a spontaneous perforation. Total cystectomy with bilateral ureterocutaneostomy was performed. She died due to sepsis 13 days after the operation. Histologically, the tumor was composed of carcinomatous and sarcomatous elements. The carcinomatous element was compatible with squamous cell carcinoma and the sarcomatous element was composed of undifferentiated malignant spindle cells. Immunohistochemical examination showed that the carcinomatous component was positive for keratin and human chorionic gonadotropin (HCG) and the spindle cell component positive for vimentin, desmin and HCG. Therefore, we diagnosed the tumor as sarcomatoid carcinoma. We reviewed 56 cases of carcinosarcoma of the bladder in Japan and discussed the clinicopathology of the disease. 相似文献
48.
Analgesic mechanism of calcitonin 总被引:2,自引:0,他引:2
Yoshimura M 《Journal of bone and mineral metabolism》2000,18(4):230-233
Calcitonin is employed in clinical treatment to improve bone mass in osteoporosis and to relieve its accompanying pain, but
its analgesic mechanism is still unclear. Using ovariectomized (OVX) rats that are well known as an animal model of osteoporosis,
the antinociceptive effect of elcatonin ([Asu1,7] eel calcitonin, ECT), a synthetic derivative of eel calcitonin, was examined with the tail-withdrawal nociceptive test.
Prolonged hyperalgesia was induced by OVX, and the antinociceptive effect of ECT was proved because peripherally and repeatedly
administered ECT improved hyperalgesia. This effect of ECT was completely abolished by injections of p-chlorophenylalanine (PCPA), an inhibitor of serotonin biosynthesis, suggesting that the serotonergic system may be involved
in antinociception. Spinal cord slices that retained an attached dorsal root were prepared, and blind whole-cell recordings
were made from substantia gelatinosa (SG, lamina II) for electrophysiological analyses of a relationship between the effect
of ECT and the serotonergic system. The descending serotonergic fibers, one of the inhibitory systems for nociceptive transmission,
originate from the nucleus raphe magnus and terminate preferentially on SG of the spinal dorsal horn. Excitatory postsynaptic
currents (EPSCs) evoked by dorsal root stimulation were then recorded from SG neurons, and the effects of serotonin on the
EPSCs were compared in sham-operated and OVX rats. In addition, influence of ECT administration to OVX rats on the effects
of serotonin was also examined. Glutamatergic short- and long-latency EPSCs, mediated by Aδ and C afferent fibers, respectively,
were observed after stimulation of the dorsal root, and both were depressed in amplitude by serotonin in sham rats, whereas
only Aδ-mediated EPSCs but not C-mediated were inhibited in OVX rats. Interestingly, C-mediated EPSCs were inhibited by serotonin
in ECT-treated OVX as well as sham rats. A relationship between the fact that OVX induced hyperalgesia and that ECT alleviated
this hyperalgesia was well correlated with changes in serotonergic inhibition of C-mediated EPSCs. These results suggest an
alteration in the spinal serotonergic receptors that control the nociceptive transmission. Receptor-binding assay using spinal
membranes and [3H]-8-OH-DPAT as a radioactive ligand was used to assess the change in the receptors. Although the level of [3H]-8-OH-DPAT-binding sites was decreased in OVX rats compared with sham rats, this reversed to the normal level in ECT-treated
OVX rats. All the results strongly suggest that the behavioral and electrophysiological changes may be caused by an alteration
in the level of spinal serotonergic receptor expression.
Received: Dec. 15, 1999 / Accepted: Jan. 7, 2000 相似文献
49.
Aim: To establish techniques for producing somatic and gennline chimeric chicken by transferring blastodennal cells fused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile unincubated white Leghom and Rhode Island red chicken eggs were fused with electroporation. The treated cell suspension was transferred to the recovery medium (DMEM containing 10% FBS) and was injected into the subgerminal cavity of recipient tmincubated embryos (stage X). Results: Of 177 recipient embryos injected with the fusing blastodermal cells, 6 (3.4%) survived to hatching. Somatic chimerism was examined in the melanocyte of the feather. The presence of feathers originating from the donor cell was observed in 1 bird (16.7%) out of the 6 hatched birds. After 21 days of incubation two birds out of five embryos were subjected to polymemse chain reaction (PCR) analysis for W-chromosome-specific DNA for each tissue. One bird possessed W-chromosome-specific DNA in the stomach, and the other exhibited the same DNA in the left and right gonads and other tissues, but not the stomach. Conclusion: Recipient embryo having electrofused blastodermal cells yields somatic and germline chimeric chickens more successfully.(Asian J Androl 2000 Dec;2:271-275) 相似文献
50.
Comparative study on semen quality of one- and two-year-old ganders during the entire reproductive season 总被引:1,自引:1,他引:0
Aim: To evaluate the characteristics of semen produced by one- and two-years old White Italian ganders duringentire reproductive season, in order to clarify whether the young ganders are responsible for a low fertility rate in yougeese. Methods: Males were kept individually in cages under natural light. Semen was collected by dorso-abdonhal massage three times a week and routine examination was performed. Results: The mean ejaculate volume (2and 1.6 mL, respectively) and sperm concentration (323 and 281 × 10~6/mL, respectively) in one-year-old gandwere higher than those of two-year-old ones. The percentages viable spermatozoa of one- and two-year-old gandwere similar (91.4 and 92.3%, respectively), but the percentage of normally formed viable spermatozoa was signicantly higher in the older ganders than in the younger (47.8 and 42.9%, respectively, P < 0.05). Conclusion:The semina from one- or two-year-old Ganders were similar in regard to volume, sperm density and sperm motility,the percentage of norma 相似文献