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The jugular bulb varies widely in position and dimensions. A high jugular bulb is not an uncommon finding in temporal bones. Besides our five cases with different clinical manifestations, we review 52 cases diagnosed clinically and published previously in the English literature. The high jugular bulb occurs more often on the right temporal bone. Certain pathologic conditions, such as an abnormal bone formation, an aberrant sinusojugular system, or decreased pneumatization of the mastoid bone, may predispose an individual to its occurrence. Most people with this anatomical variation remain asymptomatic. However, various otologic problems and symptoms may be attributed to this condition. A high resolution computed tomography scan is the most convenient diagnostic tool at present. Law projection plain mastoid radiography may reveal a high jugular bulb in certain cases, providing a preoperative warning to an otologic surgeon. An exploratory tympanotomy is not suggested for those with a high jugular bulb with a conductive hearing loss, while jugular vein ligation has been reported to have good results in alleviating intractable pulsatile tinnitus. For most asymptomatic patients, regular long-term follow-up is recommended.  相似文献   
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Bilateral lesions in the most posterodorsal aspects of the amygdala in female rats resulted in immediate and dramatic weight gains on a standard lab chow diet. The rate of weight gain returned to normal by Day 20, but the difference in body weight between animals with amygdaloid lesions and those with sham lesions was maintained for the duration of the study (60 days). Because rats with posterodorsal amygdaloid lesions have also been found to be hyperinsulinemic, it is hypothesized that the lesions result in a similar, though smaller, version of the syndrome that follows lesions of the ventromedial hypothalamus.  相似文献   
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STUDY OBJECTIVE: To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis. DESIGN: Prospective, cross-sectional clinicomicrobiological study with informed consent. SETTING: Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic. PATIENTS: Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks. MEASUREMENTS AND RESULTS: Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively. CONCLUSIONS: P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%).  相似文献   
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The human adenovirus 5 E1B 55-kDa protein is required for efficient nucleocytoplasmic transport of late viral mRNAs. This protein is shown to have RNA-binding activity which maps to a region of the protein with homology to a family of RNA-binding proteins and which has been shown previously to be essential for functionality of the protein in vivo.  相似文献   
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This study reports the establishment of alpha-amylase-producing human parotid pleomorphic adenoma cell lines (2HP and 2HP1) which have been maintained in culture for over 1 yr. The procedures required preparation of cellular clumps from tumor tissue and plating them on plasma clot or precoated dishes. During the initial phase of growth they required modified MCDB-153 medium without serum. When cells showed signs of degeneration they were changed to MCDB-153 medium containing first 2% and then 10% heat inactivated fetal bovine serum. Although cells grew well in MCDB-153 containing 10% serum, the epithelial cell morphology was not distinct. Therefore, the growth and morphology of cells grown in MCDB-10% serum were compared with those in RPMI growth medium containing 10% fetal bovine serum and F12 containing 10% agammaglobulin newborn bovine serum. Although the growth of cells was a little slower in F12 medium than those in MCDB and RPMI, the epithelial cell morphology was maintained better than in other growth media. The cells of 2HP and 2HP1 produce low levels of alpha-amylase and relatively high levels of alpha-amylase mRNAs of 1176 and 702 bp and contain neurofilament-160, a neuronal-specific marker. The cells of 2HP1 are tumorigenic when tested in athymic mice, but the cells of 2HP are not. The establishment of amylase-producing human parotid adenoma cell lines of different characteristics in culture provides a new opportunity to study the mechanisms of differentiation and transformation, and regulation of alpha-amylase in these cells.  相似文献   
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A chelating resin, PSGI, was synthesized by the radical polymerization of GMA‐IDA, DVB, and styrene for the removal of Cu(II), Co(II), and Cd(II) from an aqueous solution. The characteristic functional groups and chemical composition of PSGI were analyzed by Fourier transform infrared spectroscopy and elemental analysis of C, H, and N. The equilibrium adsorption capacities of PSGI from their single‐metal ion solutions were 1.46 mmol/g for Cu(II), 1.02 mmol/g for Co(II), and 1.10 mmol/g for Cd(II). The adsorption isothermal of Cu(II) by PSGI followed the Langmuir isotherm. Increasing the concentration (0–0.1 M) of KCl in Cu(II) solution affected the adsorption behavior slightly. Within the pH range of 2–5.5, decreasing the pH of the Cu(II) solution did not produce remarkable changes in the equilibrium adsorption capacities. The adsorption capacities of PSGI for Cu(II) did not cause significant change during the repeated adsorption–desorption operations. The competitive adsorption tests verified that this resin had good adsorption selectivity for Cu(II) with the coexistence of Co(II) and Cd(II). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2123–2130, 2004  相似文献   
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The accuracy of single-beam dose profiles used in the algorithm of the Gamma Knife treatment planning system (Leksell GammaPlan) is verified. EGS4 Monte Carlo calculation was employed to calculate the dose distributions of single-beams in a spherical water phantom with diameter 160 mm. The beams were directed to the center of the phantom. Collimators of 4, 8, 14, and 18 mm sizes were studied. The single-beam dose profiles provided by Elekta (Manufacturer of Leksell Gamma Knife) were excellently consistent with the results of Monte Carlo for the 4, 14, and 18 mm collimators. The maximum discrepancy was less than 3% at all radial distances. For the 8 mm collimator, the maximum discrepancy was 8% in the relative dose in the radial distance range from 4.3 mm to 5.2 mm. Excellent agreement in dose profiles along x, y, and z axes for all collimator helmets by summing over all 201 sources was observed between the cases using the default single-beam dose profiles and the calculated Monte Carlo results, except for the 8 mm collimator helmet along z axis. Such difference may however be too small to give a clinical significance.  相似文献   
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BACKGROUND: Tacrolimus (FK506) may represent a major advance in the management of allograft rejection after solid organ transplantation. In August 1994 a European heart transplantation pilot study was initiated to assess the efficacy and safety of tacrolimus when administered exclusively through an oral route. METHODS: Eighty-two heart transplant recipients were randomized to treatment (2:1 ratio) with either tacrolimus- (n=54) or cyclosporine-based therapy (n=28). RESULTS: No significant differences were evident between the two treatment groups in either rejection or survival rates at 1 year. Kaplan-Meier estimates of the freedom from rejection were 26.3% and 18.5%, respectively, for the tacrolimus and cyclosporine treatment groups (p=.444). Survival rates were 79.6% and 92.9% (p=.125). At 3 of the 5 centers, patients received antithymocyte globulin during the immediate postoperative period and fared better than those who did not (with acute rejection-free rates of 49.2% and 26.7% for tacrolimus and cyclosporine, respectively [p=.080], as opposed to 7.1% and 8.3% [p=.965]; patient survival rates of 84.6% and 93.3% [p=.382] vs 75.0% and 92.3% [p=.243]). The overall rates of infection, impaired renal function (31.5% vs 21.4%), and glucose intolerance (7.0% vs 4.3%) did not differ significantly between the tacrolimus and cyclosporine treatment groups. Tacrolimus seemed to possess an advantage with regard to a reduced requirement for antihypertensive therapy (59.5% vs 87.5%, p=.025). CONCLUSIONS: Immunosuppression with oral tacrolimus provides a viable alternative to treatment with cyclosporine, particularly when administered in conjunction with antibody therapy. Further studies are warranted to optimize the administration of tacrolimus in this indication.  相似文献   
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