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101.
Objective Giant pituitary adenomas (≥40 mm) pose a major management challenge. We describe the experience of a single surgeon and a dedicated neuro‐endocrine team with multimodality treatment of these tumours in three specialized institutions. Design Retrospective data set analyses. Patients Fifty‐one consecutive patients with a giant adenoma (39 endocrine‐inactive, 12 endocrine‐active; mean tumour diameter 45 mm) treated over 10 years by an endonasal transsphenoidal approach were included. All patients had surgical resection followed by radiotherapy and/or medical therapy as judged necessary. Measurements Hormonal and visual status, extent of resection, tumour control rates, complications and use of medical and radiotherapy were evaluated. Results Surgery resulted in gross total, near total and subtotal removal in21 (41%), 10 (20%) and 20 (39%) patients respectively. Complete tumour removal was associated with absence of cavernous sinus invasion (P < 0·001). Long‐term endocrine function improved in 49% of patients and new endocrinopathy occurred in 14·6%; 76% required long‐term hormone replacement therapy. Vision improved in 81·5% of the patients and there was no visual worsening. At the last follow up (median 30 months), tumour control was achieved in 96% of patients: 59% with surgery alone, 20% with surgery plus focussed radiotherapy, 18% with surgery and medical therapy and two with all three modalities. Conclusions Endonasal surgery provides effective initial treatment for patients with giant adenomas. Multimodality therapy was needed in almost 50% of patients and this rate will likely increase with longer follow up. Close collaboration of neurosurgeons with endocrinologists and radiation oncologists is essential for optimal treatment of patients with these challenging tumours.  相似文献   
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Background:  Addictive drugs activate extracellular signal regulated kinase (ERK) in brain regions critically involved in their affective and motivational properties. The aim of this study was to demonstrate the ethanol-induced activation of ERK in the nucleus accumbens (Acb) and in the extended amygdala [bed nucleus of the stria terminalis lateralis (BSTL) and central nucleus of the amygdala (CeA)] and to highlight the role of dopamine (DA) D1 receptors in these effects.
Methods:  Ethanol (0.5, 1, and 2 g/kg) was administered by gavage and ERK phosphorylation was determined in the nucleus Acb (shell and core), BSTL, and CeA by immunohistochemistry. The DA D1 receptor antagonist, SCH 39166 (SCH) (50 μg/kg), was administered 10 minutes before ethanol (1 g/kg).
Results:  Quantitative microscopic examination showed that ethanol, dose-dependently increased phospho-ERK immunoreactivity (optical and neuronal densities) in the shell and core of nucleus Acb, BSTL, and CeA. Pretreatment with SCH fully prevented the increases elicited by ethanol (1 g/kg) in all brain regions studied.
Conclusions:  The results of this study indicate that ethanol, similar to other addictive drugs, activates ERK in nucleus Acb and extended amygdala via a DA D1 receptor-mediated mechanism. Overall, these results suggest that the D1 receptors/ERK pathway may play a critical role in the motivational properties of ethanol.  相似文献   
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The seasonal distribution of Lutzomyia longipalpis was studied in two forested and five domiciliary areas of the urban area of Campo Grande; MS, from December 2003 to November 2005. Weekly captures were carried out with CDC light traps positioned on ground and in the canopy inside a residual forest and on the edge (ground) of a woodland and in at least one of the following ecotopes in peridomiciles-a cultivated area, a chicken coop, a pigsty, a kennel, a goat and sheep shelter and an intradomicile. A total of 9519 sand flies were collected, 2666 during the first year and 6853 during the second. L. longipalpis was found throughout the 2-year period, presenting smaller peaks at intervals of 2-3 months and two greater peaks, the first in February and the second in April 2005, soon after periods of heavy rain. Only In one of the woodlands was a significant negative correlation (p<0.05) between the number of insects and temperature during the first year and the climatic factors (temperature, RHA and rain) was observed. In the domiciliary areas in four domiciles some positive correlations (p< or =0.05) occurred in relation to one or more climatic factors; however, the species shows a clear tendency to greater frequency (72%) in the rainy season than in the dry (28%). Thus, we recommend an intensification of the VL control measures applied in Campo Grande, MS, during the rainy season with a view to reducing the risk of the transmission of the disease.  相似文献   
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OBJECTIVES: In old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was to determine whether there are also aging changes in the microvascular architecture and vascular dispersion of the liver that might influence liver function. METHODS: Vascular corrosion casts and light micrographs of young (4 months) and old (24 months) rat livers were compared. Fractal and Fourier analyses and micro-computed tomography were used. Vascular dispersion was determined from the dispersion number for sucrose and 100-nm microspheres in impulse response experiments. RESULTS: Age did not affect sinusoidal dimensions, sinusoidal density, or dispersion number. There were changes in the geometry and complexity of the sinusoidal network as determined by fractal dimension and degree of anisotropy. CONCLUSIONS: There are small, age-related changes in the architecture of the liver sinusoidal network, which may influence hepatic function and reflect broader aging changes in the microcirculation. However, sinusoidal dimensions and hepatic vascular dispersion are not markedly influenced by old age.  相似文献   
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Long-term immunoprophylaxis with anti-HBs immunoglobulins (HBIg) is used to prevent hepatitis B (HBV) reinfection after liver transplantation for HBV-related cirrhosis. This approach is highly expensive. A recent report proposed posttransplant HBV vaccination with a reinforced schedule as an alternative strategy to allow HBIg discontinuation. We investigated the efficacy of a reinforced triple course of HBV vaccination in 17 patients transplanted for HBsAg-positive cirrhosis 2 to 7 years earlier. The first cycle consisted of 3 double intramuscular doses (40 microg) of recombinant vaccine at month 0, 1, and 2, respectively. This was followed, in nonresponders, by a second cycle of 6 intradermal 10 microg doses every 15 days. All nonresponders then received a third cycle identical to the first one. Vaccination started 4.5 months after HBIg discontinuation, and lamivudine (100 mg/day) was given throughout the study. All patients were seronegative for HBsAg and HBV-DNA (by PCR) and positive for anti-HBe, and 7 were positive for anti-HDV. After the first cycle one patient (#5, 53 years old, male) developed an anti-HBs titer of 154 IU/L, another (#12) reached a titer of 20 IU/L and the remainder had titers <10 IU/L. At month 7, patient #5 reached a titer of 687 IU/L. After the second cycle only one additional patient (#9) had a slight response (an anti-HBs titer of 37 IU/L). After the third cycle patient #9 rose to an anti-HBs titer of 280 IU/L, patient #12 dropped to 10 IU/L, and no other patient responded. In conclusion, a highly reinforced HBV vaccination program is effective only in a few patients who had liver transplants for HBV-related cirrhosis.  相似文献   
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