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1.
BACKGROUND: Asthma mortality rates have been increasing despite our improved understanding of the pathophysiology of asthma and advanced methods of treatment. Although there are many national studies of asthma mortality rates, few studies have concentrated on subnational regions such as individual states. OBJECTIVES: We sought to determine the trends in asthma mortality in children and young adults during the last 15 years in Louisiana. METHODS: Asthma mortality data were acquired from the Louisiana State Center for Health Statistics for the years 1983 through 1997. All asthma deaths coded International Classification of Disease, Ninth Revision 493 were included in the data set along with year, sex, and rate characteristics. State population estimates obtained from the United States Bureau of Census for three 5-year periods (1983 to 1987, 1988 to 1992, and 1993 to 1997) were used to calculate crude and adjusted mortality rates. These time periods were compared with one another and with the period 1983 to 1987, which was used as a baseline. RESULTS: For all residents, the mortality rate increased from 0.41 deaths per 100,000 persons during the 1983 to 1987 time period to 0.49 and 0.63 deaths per 100,000 persons during 1988 to 1992 and 1993 to 1997 time periods, respectively. Mortality rates have increased in both the white and non-white populations over the 15-year study period, with the most pronounced increases among the non-white population. CONCLUSION: Asthma mortality rates in Louisiana have increased, particularly among the non-white population, over the last 15 years, although the results are not statistically significant. When compared with other states, asthma mortality in Louisiana is lower than in the northeast and central north states.  相似文献   
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The effect of salmon calcitonin (0.25 MRC mU/g body wt) was investigated on the serum calcium and inorganic phosphate levels of the frog. Rana tigrina. The hormone evokes hypocalcemia (on Day 1 and Day 3) which is followed by a significant hypercalcemia on Day 10. Thereafter, the level of calcium decreases again on Day 15. Calcitonin induces hypophosphatemia (on Day 3 and Day 5). Thereafter, hyperphosphatemia is recorded on Day 10. Normal serum phosphate value is achieved by Day 15. The results obtained in R. tigrina have been discussed in relation to the increased calcium deposits in the paravertebral lime sacs and to the possible enhanced secretion of the parathyroid glands.  相似文献   
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Metal-free organic polymer photocatalysts have attracted dramatic attention in the field of visible light-induced hydrogen evolution reaction (HER). Herein, we showed a polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to generate hydrogen upon quantum dot sensitization. Both of these heptazine-based systems show effective photosensitization with strong π–π interactions and enhanced photocatalytic H2 generation (24 times) as metal-free systems. Electrochemical impedance and optical measurements show effective charge transfer kinetics with decreased charge recombination, which is responsible for the enhanced photocatalytic activity. As a result, a significant high apparent quantum yield (AQY) with highest value of 10.2% was obtained for our photocatalyst OLHP/S,N-GQD10.

A polymeric O-linked heptazine polymer (OLHP) decorated with S, N co-doped graphene quantum dots (S,N-GQDs) as a photosensitizer to utilize visible light (λ > 420 nm) for hydrogen generation.  相似文献   
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Introduction

Prostate carcinoma is still a dreaded disease wanting more effective treatment and definitive early detection for a better prognosis and cure of life.

Objective

The present study was planned to investigate the correlation of vascular endothelial growth factor (VEGF) expression level and microvessel density (MVD) between the BPH and prostate cancer subjects to analyze their diagnostic and prognostic value.

Subjects and methods

Freshly diagnosed histopathologically confirmed 50 cases of prostate cancer and 50 cases of BPH were included. Expression level of VEGF was measured using Immunohistochemistry (IHC), while MVD was determined via CD34 endothelium-specific antibodies. In the case group, we have also recorded the Gleason's score of prostate cancer and investigated its correlation with angiogenic factor VEGF and MVD CD34.

Results

The study showed a statistically significant difference value of VEGF expression level between the prostate cancer and BPH group (p < 0.001). The mean MVD CD34 in the prostate cancer and BPH groups were 29.66 ± 0.21 and 9.96 ± 0.25, respectively. The difference of MVD CD34 expression between the groups was also found significant (p < 0.001). VEGF scoring was significantly correlated with Gleason's scores of prostate cancer (p = 0.005).

Conclusions

The present findings may support the assumption that VEGF and CD34 expression level might have an important role in the prediction of prostate cancer as it was significantly differed with BPH. In addition, VEGF expression level showed intense staining in the tissue samples with higher grading of prostate cancer which reveals its importance as prognostic marker.  相似文献   
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Objective. To determine the dosage of gadobenate dimeglumine (Gd-BOPTA) necessary for MRI of rheumatoid arthritis of the wrist. Design and patients. Seven wrists inflamed with rheumatoid arthritis were imaged using a dedicated 0.2-T MR unit. Four cumulative dosages of 0.0125, 0.025, 0.05 and 0.1 mmol/kg body weight (BW) Gd-BOPTA were tested. Three-dimensional T1-weighted gradient-recalled echo sequences (GRE; TR: 100 ms, TE: 18 ms, flip angle 90°, 4:55 min) were acquired prior to an intravenous injection and after each additional dosage of Gd-BOPTA. Relative enhancement, signal-difference-to-noise ratios (SDNRs) and the size of the inflamed tissue were quantified. Three radiologists independently evaluated the image quality, the size and the contrast of the enhancing tissue. Results. The readers agreed on a dose of 0.05 mmol/kg BW as satisfactory for the evaluation of the size of the inflammatory tissue and for determination of bone involvement (κ=0.9, P<0.001). Highly inflammatory pannus was depicted with adequate image contrast using 0.025 mmol/kg BW Gd-BOPTA. According to the SDNR and relative enhancement findings, a dose of 0.05 mmol/kg BW suffices for both off-center and centered regions of tissue inflammation (t-test, P<0.05). Conclusion. Gadolinium-BOPTA is an alternative contrast agent for MRI of rheumatoid disease. This study shows that a dose of 0.05 mmol/kg BW suffices at low field strength. Received: 7 June 2000 Revision requested: 22 August 2000 Revision received: 8 September 2000 Accepted: 21 September 2000  相似文献   
9.
A 10 years old, female patient presented with symptoms of abnormal movement of the body for 5 years, deviation of mouth to left side for 12 days and difficulty in walking for 12 days. We report a very rare case of Brain Stem gliomas. Clinical and imaging findings were suggestive of Brain Stem gliomas. Key words: Brain tumors, Intracranial space occupying lesion.  相似文献   
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Budd Chiari Syndrome is the eponymic designation of symptomatic post sinusoidal venous obstruction, whether or not this is associated with hepatic vein occlusion or vena caval obstruction. Dutta and associates (1) classified the syndrome into two distinct types. Type I involves obstruction to the hepatic veins while Type II pertains to an obstruction in the inferior vena cava above the entry of hepatic veins. We report a case of thoraco-abdominal aortic aneurysm presenting as Type II Budd Chiari Syndrome.  相似文献   
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