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51.
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Glycerophosphocholine (GPC) was measured in seminal plasma from 65 fertile men, 276 infertile men and 10 men before and after vasectomy, using a new enzymatic method. Extra-epididymal excretion of GPC accounted for 30% of the total seminal levels of GPC. From a diagnostic point of view, GPC determination did not appear to be a specific tool which could discriminate between secretory and excretory azoospermia. Although the seminal content of GPC was related positively to the total sperm count in both fertile and infertile men, there was an inverse relationship between the level of GPC and sperm motility when considering classes displaying the same total sperm count. This was observed in all classes from infertile men as well as in fertile men with a total sperm count lower than 200 x 10(6) sperm/ejaculate. These results suggest a possible role of GPC in the regulation of human sperm motility, which warrants further investigation.  相似文献   
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55.
There is little information available concerning whether, and to what extent, migraine-prophylactic agents interfere with the symptoms of migraine attacks. The present study is a placebo-controlled, double-blind study concerning metoprolol in classic migraine. The data refer to the symptoms of single migraine attacks. During metoprolol treatment more attacks were characterized as mild (p = 0.002), and mean global rating (an integrated estimate of headache intensity and of other discomfort) was lower (4.2 versus 5.2, p = 0.003). The mean headache intensity per attack (1.97 versus 2.15) and the mean duration (5.5 versus 6.8 h) were not significantly different. Consumption of analgesics per attack was lower during metoprolol treatment (0.6 versus 1.1; p = 0.02). Attacks with associated symptoms accompanying the headache were fewer during metoprolol treatment (p = 0.014). Total visual and non-visual aura symptoms occurred with similar frequency, but scintillations and paraesthesia were more frequent during metoprolol treatment, whereas speech disturbances were less frequent. In spite of lower consumption of analgesics, the symptoms appeared milder during metoprolol than during placebo. The pattern of changes indicates that metoprolol exerts its action via the sympathetic nervous system; peripheral vasoconstriction is hardly the underlying mechanism of action.  相似文献   
56.
Introduction: Symptom improvement was assessed as changes in the Chronic Respiratory Infection Symptom Score (CRISS) during intravenous antimicrobial exacerbation treatments among subjects from study NCT02109822.Methods: Median daily CRISS reduction (i.e., improvement) and covariates associated with CRISS reduction by Day 14 were assessed by logistic regression.Results: Among 173 subjects, median baseline CRISS was 49 [IQR 41, 56]; 93.6% had a CRISS reduction of ≥11 (minimal clinically important difference); median time to –11 reduction was 2 days [95% CI 2, 3]. The greatest median CRISS difference from baseline, on Day 17, was –26 [–29, –23]. Odds of –26 CRISS change by Day 14 were greater in subjects with higher baseline CRISS (P=.006) and younger ages (P=.041).Conclusions: CRISS response has good dynamic range and may be a useful efficacy endpoint for PEx interventional trials. The optimal use of CRISS change as an endpoint remains uncharacterized.  相似文献   
57.
Purpose: To retrospectively investigate the role of a contrast enhanced MRI (ceMRI) performed 24?h after a microwave ablation (MWA) of the lung, in predicting local tumour progression (LTP) and detecting complications compared to an unenhanced CT.

Material and methods: Forty-nine patients who underwent MWA of 77 lung metastases between 2008 and 2015 were included. All patients received an unenhanced chest CT and a ceMRI (including T2 and ceT1) 24?h after MWA. The conspicuities of the peripheral rim and the ablated tumour were scored using 1–3 scales and compared between examinations. The safety margin was measured directly (both scores ≥2) and indirectly using a subtraction method. The ability of each imaging modality to predict LTP based on safety margin width was analysed using receiver operating characteristic curves. The MRI ability to detect a pneumothorax was compared to CT.

Results: The peripheral rim was best visualised on T2 followed by T1 and CT. The tumour was best visualised on CT, followed by T1 and T2. Direct safety margin measurement was possible on CT, ceT1 and T2 in 68.8%, 64.9% and 27.3% of cases, respectively. Direct CT (AUC?=?0.77) and ceT1 (AUC?=?0.76) measurements had better diagnostic performance than indirect CT (AUC?=?0.72), ceT1 (AUC?=?0.70) and T2 (AUC?=?0.69) measurements. The MRI sensitivity and specificity for pneumothorax were 60.8% and 87.0%, respectively. Only one pneumothorax >1?cm was missed.

Conclusions: A ceMRI performed 24?h after MWA of lung tumours has a similar ability to predict LTP and detect important complications as a CT has.  相似文献   
58.

Objective

Administration of postoperative chemotherapy to patients with completely resected stage I NSCLC is still a matter of debate. The aim of the present study was to evaluate the value of different baseline 18F-FDG PET parameters in identifying surgical stage I NSCLC patients who are at high risk of recurrence, and thus are indicated for further postoperative treatment.

Methods

This is a retrospective study, which included 49 patients (28 males, 21 females) with the median age of 69 years (range 28–84), who had pathologically proven stage I NSCLC. All patients underwent 18F-FDG PET/CT at baseline followed by complete surgical resection of the tumor (R0). Baseline SUVmax, MTV and TLG were measured. Patients’ follow-up records were retrospectively reviewed, and DFS (disease-free survival) was assessed. For each parameter, the most accurate cut-off value for the prediction of recurrence was calculated using the ROC curve analysis and the Youden index. DFS was evaluated for patients above and below the calculated cut-off value using the Kaplan–Meier method and the difference in survival between the two groups was estimated using the log-rank test.

Results

Median observation time of the patients after surgery was 28.7 months (range 3.5–58.8 months). 9 patients developed recurrence. The calculated cut-off values for SUVmax, MTV and TLG were 6, 6.6 and 33.6, respectively. Using these cut-offs, the observed sensitivity for SUVmax, MTV and TLG for prediction of recurrence was 100%, 89% and 89%, respectively, while the observed specificity was 43%, 73% and 65%, respectively. The difference in survival between patients below and above the cut-off value was statistically significant in all three studied parameters. The highest AUC was observed for MTV (AUC?=?0.825, p?=?0.003), followed by TLG (AUC?=?0.789, p?=?0.007), and lastly SUVmax (AUC?=?0.719, p?=?0.041). ROC curve analysis showed that volumetric parameters had better predictive performance than SUVmax as regards recurrence.

Conclusion

PET-derived parameters at baseline were predictive of recurrence in stage I surgical NSCLC patients. Moreover, the metabolic volume of the tumor was the most significant parameter for this purpose among the studied indices.
  相似文献   
59.
Aim(s)  This study validates an instrument for measuring the effectiveness of nursing practice councils and offers a framework for measuring and understanding shared governance.
Background  Empowerment results from the vertical alignment of nursing group power with nursing unit power practices. The field lacks an instrument for measuring nurses' practice of power.
Method(s)  Two studies ( n 1 = 119; n 2 = 248) are used to validate the Nursing Practice Council effectiveness scale (NPCes).
Results  NPCes is a valid and reliable index of nursing practice council effectiveness. This study suggests specific diagnostic tools to understand two levels for actualized power, one at the group or departmental level and one at the unit level.
Conclusion(s)  NPCes and the Sieloff-King Assessment of Group Power within Organizations (SKAGPO) can be used together to improve examination of shared governance. Examining group power as well as unit-level practices may give a more complete view of barriers to nurse empowerment.
Implications for nursing management  Changing nursing power and practices in an organization may be made more effective by engaging and monitoring vertical alignment of strategies fostering power competencies among nurse leaders and simultaneously supporting nursing practice councils as a means of exercising nurse authority at the unit level.  相似文献   
60.
LeMarbre  P; Rinehart  JJ; Kay  NE; Vesella  R; Jacob  HS 《Blood》1981,58(5):994-999
The mononuclear phagocyte is well established as an in vitro cytotoxic effector cell for certain human tumors. The mechanism(s) for this action remains unclear. Increased levels of lysozyme, a cationic enzyme synthesized in large amounts by mononuclear phagocytes, are associated with increased resistance to transplantable animal tumors. In this study, we provide evidence that human lysozyme, isolated from the urine of leukemic patients, has marked potentiating effects on human monocyte- tumor-cell cytocidal activity. In addition, lysozyme-exposed monocytes incorporate increased quantities of leucine, suggesting that monocytes are capable of amplifying their own metabolic activation by secreting an endogenous constituent. Tri-N-acetyl-glucosamine, a competitive inhibitor for the active site of lysozyme, inhibits cytocidal activity. Conversely, protamine, an extraneous albeit similarly positively charged molecule, increases monocyte-mediated tumor cytotoxicity; this protamine effect is negated by heparin. We conclude that lysozyme, at least partially by its positive charge, is capable of enhancing in vitro monocyte tumor cell cytotoxicity; its in vivo secretion may potentiate monocyte-tumor-cell interaction.  相似文献   
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