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This study has shown that the retinae of Prototherian (egg-laying) mammals possess two neuronal types that are present in non-mammalian retinae, but absent or morphologically different in the retinae of Eutherian (placental) mammals. First, endogenous serotonin-like immunoreactivity has been localized in a population of presumptive amacrine cells in the platypus retina, the first such report in a mammalian retina. Second, the protein kinase C-immunoreactive (PKC-IR) bipolar cells in the echidna retina appear similar to the PKC-IR bipolars in the chicken retina, in that their dendrites give rise to a Landolt's club and their axons are multistratified. By contrast, the PKC-IR rod bipolar cells in the rabbit and in the brushtail possum, a Metatherian (marsupial) mammal, have no Landolt's clubs and their axons form terminal lobes in the innermost stratum of the inner plexiform layer.  相似文献   
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采用SD大鼠一侧大脑中动脉阻断致局限性脑缺血模型。脑缺血后迅速断头置于液氮中,HPLC外标定量法测定各磷脂组分。观察脑缺血1、5、15、60、360min时脑细胞膜磷脂含量变化。结果显示,PI在缺血早期显著低于对照组(P<0.01~0.05);PE、PC早期仅呈下降趋势,PE在缺血60min组、PC缺血360min组显著低于对照组(P<0.01~0.05)。PS在缺血全过程中变化轻微(P>0.05)。提示磷脂降解与脑缺血存在一定关系,缺血早期首先出现脑细胞膜功能磷脂降解,膜结构磷脂则在缺血后期出现显著变化,且PE较PC优先降解。  相似文献   
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PURPOSETo evaluate the efficacy, safety, and results of direct thrombolytic therapy in intracranial dural sinus thrombosis by infusion of alteplase (recombinant tissue plasminogen activator).METHODSNine patients were treated during a 2-year period for intracranial dural sinus thrombosis. A microcatheter was placed directly into the thrombus in the dural sinus via the transfemoral route. Thrombolysis was initiated with a rapid injection of 10 mg of alteplase over 10 minutes, followed in 3 hours by a continuous infusion of 50 mg, then a continuous infusion at 5 mg per hour until complete thrombolysis or a total dose of 100 mg per day had been reached. Repeat thrombolysis was tried the following day if complete recanalization did not occur at 100 mg per day.RESULTSSuccessful recanalization with improvement of symptoms was achieved in all cases. Time required for complete thrombolysis was between 8 and 43 hours. The total dose of alteplase ranged from 50 to 300 mg. Complications of a small intrapelvic hemorrhage and oozing at a femoral puncture site occurred in separate cases, but were not related to the amount of infused alteplase. MR venograms obtained 1 to 4 weeks after the procedure showed no evidence of reocclusion of the dural sinuses.CONCLUSIONDirect fibrinolytic therapy with alteplase is safe, fast, and effective in treating dural sinus thrombosis. However, to prevent hemorrhagic complications, further studies are required to determine its optimal dose and proper rate of administration.  相似文献   
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Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
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The study aimed to compare the longitudinal assessment of autonomic nerve function by computerized infrared pupillometry and standard cardiovascular tests in adolescents with diabetes. Adolescents (n = 150) were assessed at two time points (T1 and T2). The median time interval between assessments was 1.5 (range 0.9–3) years. At T1 the median age was 14.5 (range 8.3–19.5) years and the median duration was 6.5 (range 1.1–16) years. The pupillary variables assessed included the resting pupil diameter, the maximum constriction velocity, and the reflex amplitude of constriction. Heart rate reflexes were assessed in response to deep breathing, the Valsalva manoeuvre, and on standing from a lying position (30/15 ratio). Between visits there was a significant decrease in maximum constriction velocity (6.0 mm s?1 vs 6.3 mm s?1, p = 0.0001) and resting pupil diameter (6.2 mm vs 6.3 mm, p = 0.001). At reassessment pupillary abnormalities increased from 32 (21 %) to 45 (30%), with 17 (54 %) of the initial abnormalities persisting. Adolescents with abnormally slow maximum constriction velocity compared to those with normal maximum constriction velocity had a higher glycated haemoglobin (HbA1c%) at T2 (p = 0.02) and between assessments (p = 0.01). Cardiovascular test abnormalities did not increase between visits and the persistence of initial abnormalities was low (21 %). In summary, pupillometry appears a more sensitive test of autonomic nerve dysfunction in adolescents with diabetes than assessment of cardiovascular reflexes.  相似文献   
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A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.  相似文献   
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