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41.
Yessotoxin (YTX), a disulfated polyether toxin, was isolated from cultured cells of the marine dinoflagellate Protoceratium reticulatum and unambiguously identified by high-performance liquid chromatography, 1H NMR, and MS data. The result is the first to confirm toxigenicity of this species and demonstrate it as one of the biogenetic origins of YTX found in shellfish.  相似文献   
42.
BACKGROUND: The aim of this study was to determine the impact of respiratory function and bacterial colonization of the lower airway on the quality of life of patients with chronic, stable bronchitis (CB). MATERIALS AND METHODS: A series of 41 patients with stable CB was studied (age: 63.8; standard deviation (SD) 9.1 years; FVC% 91.0 (18.9); FEV1% 74.6 (23.7); FEV1/FEC 62.8 (11.2) with normal thoracic radiography. Patients with previous diagnosis of bronchiectasia, bronchial asthma and/or positive bronchodilatory tests (> 15%) were not included in the study. Bacterial growth in a sputum sample of grade 4-5 of the Murray-Washington scale was considered diagnostic of bronchial colonization. Measurement of the quality of life was performed with the Nottingham Health Profile (NHP) and the St. George Respiratory Questionnaire (SGRQ). RESULTS: The patients presented a moderate alteration in their quality of life with scores over 25 in most of the dimensions of the NHP and the SGRQ. In 9 out of 41 cases (22%), the sputum cultures demonstrated bronchial colonization with the most frequently isolated bacterias being Haemophilus influenzae and Moraxella catarrhalis. Multivariate analysis performed with the quality of life as the dependent variable showed an association between FEV1/FEC1 and the SGRQ score (R2 = 0.18), and energy (R2 = 0.09) and physical mobility (R2 = 0.05) of NHP. CONCLUSIONS: Bronchial obstruction is the main determinant in the quality of life in patients with stable CB. Colonization of the lower airway is observed in 22% of the patients and also influences the quality of life of the patients but to a much lesser extent.  相似文献   
43.
Snoring, a symptom which may indicate the presence of the obstructive sleep apnoea syndrome (OSA), is also common in the general population. Recent studies have suggested that the acoustic characteristics of snoring sound may differ between simple snorers and OSA patients. We have studied a small number of patients with simple snoring and OSA, analysing the acoustic characteristics of the snoring sound. Seventeen male patients, 10 with OSA (apnoea/hypopnoea index (AHI) 26.2 events x h(-1)) and seven simple snorers (AHI 3.8 events x h(-1)), were studied. Full night polysomnography was performed and the snoring sound power spectrum was analysed. Spectral analysis of snoring sound showed the existence of two different patterns. The first pattern was characterized by the presence of a fundamental frequency and several harmonics. The second pattern was characterized by a low frequency peak with the sound energy scattered on a narrower band of frequencies, but without clearly identified harmonics. The seven simple snorers and two of the 10 patients with OSA (AIH 13 and 14 events x h(-1), respectively) showed the first pattern. The rest of the OSA patients showed the second pattern. The peak frequency of snoring was significantly lower in OSA patients, with all but one OSA patient and only one simple snorer showing a peak frequency below 150 Hz. A significant negative correlation was found between AHI and peak and mean frequencies of the snoring power spectrum (p<0.0016 and p<0.0089, respectively). In conclusion, this study demonstrates significant differences in the sound power spectrum of snoring sound between subjects with simple snoring and obstructive sleep apnoea patients.  相似文献   
44.
Infectious causes of Pancoast's syndrome are extremely rare. We describe the case of a patient with Pancoast's syndrome due to chronic pneumonia resulting from Pasteurella multocida. The patient was not immunosuppressed and had had no contact with animals. The diagnosis was made by transthoracic needle aspiration and institution of therapy with cefuroxime-axetil resulted in resolution of his symptoms.  相似文献   
45.
This study was undertaken to assess whether peripheral blood mononuclear cells (PBMC) isolated from Brown Swiss (Br) and Holstein (Ho) cows and stimulated with concanavalin A differ in response to chronic exposure to incubation temperatures simulating conditions of hyperthermia. Five multiparous Br and 5 Ho cows were utilized as blood donors. Peripheral blood mononuclear cells were subjected for 65 h to each of 5 treatments (T). Cells were exposed to 39°C continuously (T39) and three 13-h cycles at 40 (T40), 41 (T41), 42 (T42) or 43°C (T43), respectively, which were interspersed with two 13-h cycles at 39°C. Treatment T39 was adopted to mimic normothermia; T40, T41, T42, and T43 mimicked conditions of more severe hyperthermia alternating with normothermia. Measures evaluated at the end of the incubation period were proliferative response (DNA synthesis), intracellular reactive oxygen species (ROS) concentrations, and mRNA abundance of the 72-kDa heat-shock protein (Hsp72). In Br cows, DNA synthesis began to decline when PBMC were repeatedly exposed to 41°C (−22%), whereas DNA synthesis in cells isolated from Ho cows did not begin to decline until 42°C (−40%). Furthermore, under T41 and T42, DNA synthesis from Br cows was lower than in Ho(−24 and −54%, respectively). In both breeds, increased incubation temperatures caused a reduction of intracellular ROS (from −39.6 and −69.7%). Increase in incubation temperatures enhanced Hsp72 mRNA levels only in PBMC isolated from Br cows. The Hsp72 mRNA in Br cows increased significantly under T41 and T43 compared with T39. In both breeds, DNA synthesis was positively and negatively correlated with intracellular ROS and Hsp72 mRNA abundance, respectively (r = 0.85 and r = −0.70, respectively). Results indicated that PBMC from Br cows are less tolerant to chronic heat exposure than those from Ho cows, and that the lower tolerance is associated with higher expression of Hsp72, suggesting that the same level of hyperthermia may be associated with a differential decline of immune function in the 2 breeds.  相似文献   
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