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The objective of this observational prospective study was to investigate the effect of depression on short-term outcome after lumbar spinal stenosis (LSS) surgery. Surgery was performed on 99 patients with clinically and radiologically defined LSS, representing ordinary LSS patients treated at the secondary care level. They completed questionnaires before surgery and 3 months postoperatively. Depression was assessed with the 21-item Beck Depression Inventory (BDI). Physical functioning and pain were assessed with Oswestry disability index, Stucki Questionnaire, self-reported walking ability, visual analogue scale (VAS) and pain drawing. Preoperatively, 20% of the patients had depression. In logistic regression analyses, significant associations were seen between preoperative depression and postoperative high Oswestry disability and Stucki severity scores and high intensity of pain (VAS score). In subsequent analyses, the patients with continuous depression, measured with BDI (60% of the patients who had preoperative depression), showed fewer improvements in symptom severity, disability score, pain intensity and walking capacity than the patients who did not experience depression at any phase. In those patients who recovered from depression, according to BDI-scores (35% of the patients with preoperative depression), the postoperative improvement was rather similar to the improvement seen in the normal mood group. In the surgical treatment of LSS, we recommend that the clinical practice should include an assessment of depression.  相似文献   
283.
The aim of this study was to assess intra- and inter-observer variability of left (LA) and right atrial (RA) strain indices obtained by two-dimensional speckle-tracking echocardiography (2D-STE) in a healthy group of individuals at low-altitude and after rapid ascent to high-altitude in order to provoke altered systemic and pulmonary hemodynamics otherwise seen in various cardiac diseases. Twenty healthy subjects underwent transthoracic echocardiography during a baseline examination at low-altitude (424 m) as well as 7, 20 and 44 h after arrival at high-altitude (4559 m). Atrial strain indices (i.e. reservoir, conduit and contractile strain) were determined off-line by two independent observers. Intra- and inter-observer reproducibility of variables was assessed by intra-class correlation coefficients (ICCs), coefficients of variation and Bland Altman plots. Heart rate, systemic blood pressure and pulmonary artery pressure increased significantly from low-altitude to the first examination at high-altitude. Intra-observer ICCs were ≥0.90 except for RA conduit strain with an ICC of 0.86. The mean intra-observer differences were small and limits of agreement of relative differences were narrow for all atrial strain parameters (<3 and <16%, respectively). Inter-observer ICCs (0.80–0.90), mean biases and limits of agreement (<4 and <20%, respectively) were greater than intra-observer results for all parameters. Intra- and inter-obserer ICCs for all atrial strain variables did not differ between low- and high-altitude. 2D-STE-derived bi-atrial strain indices have excellent intra- and moderate inter-observer reproducibility with no effect of high-altitude-induced hemodynamic changes on reliability results.  相似文献   
284.
High altitude pulmonary edema: a pressure-induced leak   总被引:1,自引:0,他引:1  
High altitude pulmonary edema (HAPE) is a non-cardiogenic pulmonary edema that can occur in healthy individuals who ascend rapidly to altitudes above 3000-4000m. Excessive pulmonary artery pressure (PAP) is crucial for the development of HAPE, since lowering pulmonary artery pressure by nifedipine or tadalafil (phosphodiesterase-5-inhibitor) will in most cases prevent HAPE. Recent studies using microspheres in swine and magnetic resonance imaging in humans strongly support the concept and primacy of nonuniform hypoxic arteriolar vasoconstriction to explain how hypoxic pulmonary vasoconstriction occurring predominantly at the arteriolar level can cause leakage. Evidence is accumulating that the excessive PAP response in HAPE-susceptible individuals is due to a reduced NO bioavailability. HAPE-susceptible individuals show an endothelial dysfunction in the systemic circulation in hypoxia. Lower levels of exhaled NO in hypoxia before and during HAPE suggest that this abnormality also occurs in the lungs and polymorphisms of the eNOS gene are associated with susceptibility to HAPE in the Indian and Japanese population.  相似文献   
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We identified 17 BRCA1mutations in 86 Austrian breast and ovarian cancer families (20%) that were screened for mutations by denaturing high-performance liquid chromatography (DHPLC) and the protein<0B> <0R>truncation test (PTT). Eleven distinct mutations were detected, 4 of them (962del4, 2795del4, 3135del4 and L3376stop) not previously reported in families of non-Austrian origin. In addition, 6 rare missense mutations (allele frequency < 1%) with unknown biological effects were identified. Four mutations occurred more than once in the Austrian population: 2795del4 (3 times), Cys61Gly (3 times) 5382insC (2 times) and Q1806stop (2 times). Haplotype analysis of the 4 recurrent mutations suggested a common ancestor for each of these. Thirty-four breast cancer cases from 17 families with BRCA1 mutations were further analyzed. We observed a low median age of onset (39.5 years). Sixty-eight percent of all BRCA1 breast cancer cases had negative axillary lymph nodes. This group showed a significant prevalence of a negative estrogen and progesterone receptor status and stage I tumors compared with an age-related, node-negative control group. The prevalence of grade III tumors was marginally significant . Survival analysis either with a control group matched for age (within 5 years), grade, histologic subtype and estrogen receptor status, or with an age-related, node-negative comparison group, showed no statistical difference. Int. J. Cancer 77:354–360, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
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The response of the colon to aldosterone isbelieved to be an important adaptive mechanism toexcessive sodium losses in diarrhea. However, the degreeto which mineralocorticoid activity actually influences fecal output of sodium in people with diarrheais unknown. To gain insight into this question, 10normal people were treated with placebo, fludrocortisone(an aldosterone agonist), and spironolactone (an aldosterone antagonist) during threeexperimental periods lasting nine days. On days 5-8,diarrhea was induced by ingestion of phenolphthalein.Diet was controlled. Fecal sodium was 40 meq/day onplacebo and 29 meq/day on fludrocortisone, consistentwith mineralocorticoid stimulation of intestinal sodiumabsorption. However, contrary to our expectations,spironolactone therapy was also associated with a fall in fecal sodium output, to 28 meq/day. Toexplain this paradoxical effect of spironolactone, wesuggest that sodium depletion caused by spironolactone'snatriuretic action on the kidney caused the release of an unknown stimulant of intestinalsodium absorption, whose action more than overcame thereduced colonic absorption resulting from inhibition ofaldosterone activity by spironolactone. This interpretation implies that the intestinaladaptation to sodium depletion in diarrhea involves bothaldosterone and an aldosterone independent factor,working in concert to reduce fecal sodiumoutput.  相似文献   
289.
Purpose: The aim of the present study was to investigate the influence of smoking on different parameters such as oocyte count, embryo score, and basal hormone values within the scope of in vitro fertilization–embryo transfer (IVF-ET). Methods: Eight hundred thirty-four women undergoing IVF-ET treatment were classified as smokers or nonsmokers on the basis of questionnaires. Additionally, we divided them into three groups according to their stimulation protocol—combined stimulation [I; clomiphene citrate plus human menopausal gonadotropin (hMG)], ultrashort [II; gonadotropin releasing hormone agonist (GnRHa) plus hMG or follicle-stimulating hormone (FSH)], and long downregulation protocol (III)—and further classified again as smokers or nonsmokers within the groups. Results: In general, smoking patients were significantly (P = 0.0195) younger than nonsmokers and showed a significantly (P = 0.0379) lower embryo score and a tendency (P = 0.0931) to produce fewer oocytes. There was no significant difference concerning the number of normally or pathologically fertilized and transfered oocytes and embryos suitable for cryopreservation. Women who smoked had significantly (P = 0.0112) higher basal 17--estradiol (E 2 ), luteinizing hormone (LH) (P = 0.0001), and dehydroepiandrosteronesulfate (DHEAS) (P = 0.0039) levels, but their basal human prolactin (HPRL) levels were significantly (P = 0.0033) lower than those of nonsmokers. According to the stimulation protocol used, we found the following results. Smoking patients in group I showed a significantly (P = 0.023) lower embryo score and produced fewer oocytes (P = 0.0113), with fewer of them being fertilized (P = 0.0072) and transferred (P = 0.0067). Women who smoked had significantly (P = 0.0002) higher basal LH levels, but their HPRL levels were significantly (P = 0.031) lower than those of nonsmokers. Furthermore, they had a thinner endometrium on the day of embryo transfer (P = 0.0366). In group II we measured significantly elevated basal E 2 levels (P = 0.0089) and higher LH values (P = 0.0092) in smokers. Group III showed a trend (P = 0.0565) toward lower HPRL values in smokers. Conclusions: Although the fertilization rate of oocytes and the pregnancy rate were not significantly different between smokers and nonsmokers, we found significantly alterated hormonal parameters and negatively influenced oocyte parameters, particularly after clomiphene stimulation. So we might consider using only GnRHa protocols for smoking patients. Additionally, we advise our patients to stop smoking before an IVF-ET treatment because of the complex effects of smoking on the reproductive and hormonal system.  相似文献   
290.
Latex allergy has been studied in detail in Europe and the US over the past two decades, resulting in specific guidelines that succeeded in reducing its incidence in high-risk populations within the medical field. How these developments have affected high-risk populations outside the health care scenario is an important unanswered question. In addition, a second wave of latex allergy may occur in nations that are striving to attain higher economic and technologic standards, including population-dense countries such as China. Therefore, the application of Hevea allergens in novel diagnostic assays and the development of specific latex immunotherapy will provide new opportunities for latex allergy research. In this review, we summarize current knowledge on the immunological properties of the 13 officially accepted Hevea brasiliensis latex allergens.  相似文献   
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