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91.
92.
Nitric oxide (NO) production and carbon monoxide (CO) production are increased in inflammatory lung diseases. Although there are some pieces of evidence for hormonal modulation by estrogen, little is known about exhaled NO and CO during the ovarian cycle. In 23 subjects, we measured exhaled NO and CO by an online analyzer. Significantly higher levels of exhaled NO were found at the midcycle compared with those in the premenstrual period or during menstruation. Higher levels of CO were after ovulation and reached a peak in the premenstrual phase. The lowest levels of CO were observed in the first days of the estrogen phase. In males, there was no significant variation in exhaled NO and CO. Exhaled NO and CO levels vary during the ovarian cycle in women, and this fact should be taken into account during serial measurements of these markers in the female population. 相似文献
93.
94.
Antczak A Kharitonov SA Montuschi P Gorski P Barnes PJ 《Respiration; international review of thoracic diseases》2005,72(6):594-599
BACKGROUND: Sputum induction is increasingly used to study both cellular and biochemical composition of the airways. However, there is a significant rise in the percentage of neutrophils at 8 h after inhalation with hypertonic saline. OBJECTIVE: The aim of this study was to assess whether markers of inflammation in exhaled air and exhaled air condensate change after sputum induction in normal and asthmatic subjects. METHODS: We measured leukotriene B(4) (LTB(4)) and a marker of oxidative stress, 8-isoprostane, (by enzyme immunoassay) in exhaled air condensate and exhaled nitric oxide (NO; by chemiluminescence analyzer) in 15 healthy subjects (8 females, mean age 35 +/- 4 years, FEV(1) 97.4% predicted) and in 8 mild asthmatic subjects (5 males, mean age 34 +/- 2 years, FEV(1) 70.5% predicted). RESULTS: LTB(4) was significantly higher compared with baseline at 6 h but did not remain increased at 24 h after sputum induction (134.3 +/- 30.15 and 75.4 +/- 14.32 vs. 64.6 +/- 11.6 pg/ml at baseline; p < 0.02 and p > 0.05, respectively) in healthy subjects. An inverse correlation between LTB(4) and exhaled NO at 6 h after sputum induction was observed in healthy subjects (r = -0.66, p < 0.03). No increase in LTB(4) levels was observed in asthmatic patients. Baseline 8-isoprostane levels were higher in asthmatic patients than in healthy subjects (47.3 +/- 37.1 vs. 17.5 +/- 8.8 pg/ml; p < 0.01). A trend towards increased levels of 8-isoprostane could be observed at 6 and 24 h after inhalation in healthy subjects (26.2 +/- 3.7 and 26.7 +/- 3.9 pg/ml; p = 0.09 and p = 0.07, respectively). In healthy subjects, exhaled NO was significantly higher compared with baseline at 6 h and remained increased 24 h after sputum induction (7.96 +/- 3.5 vs. 5.61 +/- 1.86 ppb; p < 0.01 and p < 0.05, respectively). Exhaled NO levels were increased in asthmatic patients but did not further increase after sputum induction. CONCLUSIONS: Sputum induction with hypertonic saline causes an inflammatory response which should be considered when using the technique to monitor airway inflammation. 相似文献
95.
Expression of bcl-xL can confer a multidrug resistance phenotype 总被引:14,自引:3,他引:14
It has been suggested that genes that regulate apoptotic cell death may play an important role in determining the sensitivity of tumor cells to chemotherapy. We have recently cloned a member of the bcl-2 family, bcl- x. To test whether bcl-XL expression affects the sensitivity of tumor cells to chemotherapy, we have created stable cell lines overexpressing bcl-XL and have tested these cells for resistance to cell death induced by metabolic inhibitors and chemotherapeutic agents. Bcl-XL expression dramatically reduces the cytotoxicity of bleomycin, cisplatin, etoposide, vincristine, hygromycin B, and mycophenolic acid for up to 4 days in culture. Bcl-XL does not prevent cells from undergoing cell cycle arrest in response to these drugs, but rather prevents treated cells from undergoing apoptosis. Cell-cycle analysis on cells treated with the chemotherapeutic agents bleomycin, cisplatin, etoposide, and vincristine, show that the drugs cause growth arrest in different positions within the cell cycle. Bcl-XL expressing cells treated with chemotherapeutic drugs retain their proliferative ability after the drugs are removed. Interestingly, vincristine-treated cells expressing bcl-XL become polyploid after drug removal. These data show that bcl-XL protects cells from a wide variety of apoptotic stimuli, acts in multiple positions within the cell cycle, and confers a multidrug resistance phenotype. The ability of bcl-XL to prevent apoptotic cell death in response to chemotherapy-induced DNA damage and cell-cycle arrest may contribute to the accumulation of chromosomal aberrations within tumors. The expression of bcl-XL in tumor cells is likely to be an important indicator of chemotherapeutic efficacy. 相似文献
96.
Thway TM Clay CM Maher JK Reed DK McDowell KJ Antczak DF Eckert RL Nilson JH Wolfe MW 《The Journal of endocrinology》2001,171(1):45-55
Immortalized cell lines have many potential experimental applications including the analysis of molecular mechanisms underlying cell-specific gene expression. We have utilized a recombinant retrovirus encoding the simian virus-40 (SV-40) large T antigen to construct several immortalized cell lines of equine chorionic girdle cell lineage - the progenitor cells that differentiate into the equine chorionic gonadotropin (eCG) producing endometrial cups. Morphologically, the immortalized cell lines appear similar to normal chorionic girdle cells. Derivation of the immortalized cell lines from a chorionic girdle cell lineage was verified by immunological detection of cell-surface antigens specific to equine invasive trophoblasts. The cell lines differed, however, from mature chorionic girdle cells or endometrial cup cells in that they did not produce eCG and did express MHC class I molecules. Thus, these cell lines appear to have been arrested at a stage of development prior to final differentiation into endometrial cup cells. It was also determined that some of these cell lines as well as endometrial cups express the estrogen receptor-related receptor beta gene, but not the glial cell missing gene (GCMa) both of which are expressed in the murine and human placenta. Among these cell lines, three (eCG 50.5, 100.6 and 500.1) express eCG alpha mRNA. Since regulation of eCG alpha subunit gene is largely unknown, we investigated the signal transduction pathways regulating the eCG alpha subunit gene. Both activators of protein kinase A (PKA) and protein kinase C (PKC) induced the expression of eCG alpha subunit expression 3.2 (P<0.05)- and 1.9 (P<0.05)-fold respectively, in the eCG 500.1 cell line. However, activation of these pathways failed to induce eCG beta subunit expression. In conclusion, lines of equine trophoblast cells have been immortalized that display markers characteristic of those with the equine chorionic girdle and endometrial cup cell lineage. A subset of these cells expresses the eCG alpha subunit gene which is responsive to activators of the PKA and PKC signal transduction pathways. 相似文献
97.
Antonina A Mikocka-Walus Deborah A Turnbull Jane M Andrews Nicole T Moulding Ian G Wilson Hugh AJ Harley David J Hetzel Gerald J Holtmann 《Clin Pract Epidemiol Ment Health》2008,4(1):15
Background
In independent studies, IBD, IBS and HCV have each been associated with a substantially increased risk of psychological problems such as depression and anxiety and impairment of quality of life compared to the general healthy population. However, the relative psychological burden for each of these diagnoses is unknown as it has never been compared contemporaneously at one institution. Current local data are therefore needed to enable an evidence-based allocation of limited clinical psychological resources.Methods
Overall, 139 outpatients (64 IBD, 41 HCV, and 34 IBS) were enrolled in this cross-sectional study. The HADS, SCL90, SF-12 and appropriate disease-specific activity measures were administered. Differences between groups were assesed with ANOVA, the Chi-Square test and the independent samples t-test (two-tailed).Results
Each of the three groups had significantly lower quality of life than the general population (p < 0.05). Overall, a total of 58 (42%) participants met HADS screening criteria for anxiety and 26 (19%) participants for depression. The HCV group had a significantly higher prevalence of depression than either of the other groups (HCV = 34%, IBS = 15% and IBD = 11%, p = 0.009). In the SCL90, the three disease groups differed on 7 out of 12 subscales. On each of these subscales, the HCV group were most severely affected and differed most from the general population.Conclusion
Patients with these common chronic gastrointestinal diseases have significant impairment of quality of life. Anxiety is a greater problem than depression, although patients with HCV in particular, should be regularly monitored and treated for co-morbid depression. Evaluation of specific psychological interventions targeting anxiety is warranted.98.
O'Mahony S; Morris AJ; Straiton M; Murray L; MacKenzie JF 《QJM : monthly journal of the Association of Physicians》1996,89(9):685-690
We report our experience with small-bowel push enteroscopy in 50 patients.
The indications for push enteroscopy were: anaemia/occult gastrointestinal
bleeding (22 patients); overt gastrointestinal bleeding (17 patients);
abnormal small-bowel radiology (8 patients) and miscellaneous (3 patients).
In those with undiagnosed gastrointestinal bleeding/anaemia, abnormalities
were detected in 24/39 patients (62%): small bowel arteriovenous
malformations (AVMs) were detected in 19 (49%), and five (13%) had lesions
in the upper gastrointestinal tract. Seventeen patients had heater-probe
ablation therapy of vascular lesions: nine patients had small-intestinal
lesions, four patients gastric lesions, and four patients combined gastric
and small- intestinal lesions. In those with abnormal small-bowel
radiology, abnormalities were detected in 6/8 patients. We conclude that
(i) push enteroscopy can establish a diagnosis in a high proportion of
patients with gastrointestinal bleeding; (ii) heater-probe ablation therapy
of vascular lesions can be performed routinely at the time of enteroscopy;
(iii) a significant proportion of patients (9/50) referred for enteroscopy
with undiagnosed gastrointestinal bleeding have lesions in the
stomach/proximal duodenum missed at diagnostic endoscopy. Push enteroscopy
is a valuable diagnostic and therapeutic endoscopic procedure.
相似文献
99.
A randomized double-blind placebo-controlled crossover study of subcutaneous sumatriptan in general practice 总被引:1,自引:0,他引:1
MB Russell OE Holm-Thomsen M Rishøj Nielsen A Cleal AJ Pilgrim J Olesen 《Cephalalgia : an international journal of headache》1994,14(4):291-296
Objective. To evaluate the therapeutic response to sumatriptan in the acute migraine attack. Material and methods. Two hundred and thirty migraineurs diagnosed by their general practitioners in accordance with their usual practice were included in the study. The patients treated two migraine attacks at home by subcutaneous injection of sumatriptan or placebo for the first attack and the alternative medication, i.e. placebo or sumatriptan, for the second attack (crossover). Following treatment, a neurology resident interviewed and examined the patients, Results. When sumatriptan was compared to placebo, significantly more of the 209 evaluable patients reported headache relief at I h (56% vs 8%, p < 0.001) and 2 h (62% vs 15%, p < 0.001) after the first injection. Resolution of nausea, photophobia, and phonophobia was significantly more common in patients on sumatriptan than in those on placebo ( p < 0.001 for all comparisons). The adverse events were usually transient and of mild or moderate severity; however, three patients withdrew due to adverse events. Ninety-five percent of patients evaluated by a neurology resident met the IHS criteria for migraine. Conclusion. In general practice, sumatriptan taken subcutaneously using an autoinjector at home was an effective and well tolerated acute treatment for migraine. 相似文献
100.
AJ Larner MRCP 《International journal of clinical practice》1994,48(5):272-274
SUMMARY A case is reported of pseudohyperphosphataemia in association with a monoclonal gammopathy of undetermined significance. 相似文献