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BACKGROUND & AIMS: Breath methane measurements reflect the in situ activity of the methanogenic colonic flora. Thirty-five years ago we found that 34% of healthy adult subjects were methane producers (breath methane level >1 ppm above atmospheric methane levels). The current study presents a new survey of breath methane levels designed to determine if the activity of the methanogenic flora has changed over the past 35 years. In addition, we review insights into the methanogenic flora that have resulted from breath methane measurements. METHODS: The end-alveolar breath methane concentrations of 212 healthy adults living in the Minneapolis area were determined via gas chromatography. The influence of sex, age, and bowel movement frequency on methane production was assessed. RESULTS: The findings that 36.4% of participants were methane producers, with a mean methane concentration in these producers of 16.6 ppm, are strikingly similar to the values of 33.6% and 15.2 ppm observed 35 years ago. Neither sex nor age showed a statistically significant relationship to methane production. There was a negative correlation between frequency of bowel movements and breath methane concentration in methane producers. CONCLUSIONS: The activity of the methanogenic flora of healthy adults remained remarkably stable over the past 35 years despite widespread antibiotic use and dietary changes. A literature review revealed that many associations have been shown between methane production and clinical states, but it remains to be determined if methanogens actively influence human physiology or are simply a marker of colonic function.  相似文献   
994.
995.
Gonadotropins have been implicated in the development of epithelial ovarian cancers. These tumors are derived from ovarian surface epithelium (OSE). The purpose of this study was to determine the effects of these hormones on DNA synthesis and spontaneous cell death in primary cultures of OSE and three immortalized OSE cultures. Primary cultures of OSE cells were generated from the ovaries of women with benign disease. The effects of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on DNA synthesis and cell death were determined using [(3)H]thymidine incorporation and JAM assays. Significant inductions of DNA synthesis were demonstrated with LH in 4/12 (33%) primary cultures of OSE and 2/3 OSE cell lines and with FSH in 4/11 (36%) primary cultures of OSE and 2/3 OSE cell lines. A significant protection from cell death was also observed in the presence of FSH in 2/4 primary cultures of OSE and 1/3 OSE cell lines and in the presence of LH in 1/4 primary cultures of OSE and 2/3 OSE cell lines. The results indicate that while gonadotropins have the potential to induce cell proliferation and protect from cell death in OSE cells in vitro, their effects are variable in OSE cells from different women.  相似文献   
996.
997.
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.  相似文献   
998.
Female urinary incontinence is a common but underreported condition. Initial investigation and treatment can in most cases be undertaken without urodynamic or other detailed tests. History by the use of validated symptom and quality of life questionnaires is key to the initial investigation. Initial treatment includes pelvic floor muscle training (PFMT) regardless of the type of incontinence; lifestyle interventions and bladder retraining, anticholinergics and serotonin/noradrenaline reuptake inhibitors (e.g. duloxetine) are also included depending on the type of symptoms. In mixed incontinence the predominant symptom should be treated first. When this initial treatment is ineffective, further investigation should be offered prior to specialised treatment. Urodynamics should be considered for all patients prior to surgery. Imaging and cystoscopy to exclude pathology, for example in elderly patients with an overactive bladder, are also necessary. Newer surgical interventions should be offered after careful consideration of the risk:benefit ratio for each individual woman and the amount of evidence that is currently available to support their use.  相似文献   
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OBJECTIVE: Visual symptoms are common in patients with preeclampsia, and are caused by various underlying pathological changes in the retina. Blurred vision may be one of these symptoms. We describe three cases in which the underlying retinal pathology of blurred vision was clarified using optical coherence tomography (OCT), a novel, non-invasive ophthalmic imaging technique that provides micrometer-scale resolution images of the human retina. METHODS: Three patients with preeclampsia complained of blurred vision postpartum. In all cases, ophthalmoscopy was performed at the bedside, followed by the assessment of best corrected visual acuity, slit-lamp biomicroscopy, fluorescein angiography (FLA), and OCT. In all cases, the presence of central visual defects was examined by an Amsler-grid. RESULTS: In one case, the symptoms were bilateral. In all affected eyes, the patients complained of a relative central scotoma. Ophthalmoscopy showed edema in the affected maculae, while OCT examination clarified a serous neurosensory detachment of the macula. In one case, a neurosensory detachment was also detected in the papillomacular region of a fellow eye with no symptoms. In two cases, FLA was performed, but only in one case could we detect late leakage and subretinal exudates. The serous detachments observed showed total resolution in all cases within 5 to 10 weeks, with restoration of visual acuity. CONCLUSION: In patients with preeclampsia, OCT may provide a useful method for the precise assessment of retinal changes, distinguishing retinal edema from serous neurosensory detachments. This finding may help to clarify the pathophysiological circulatory changes seen in preeclampsia.  相似文献   
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