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961.
962.
Der elektrische Wandwiderstand des proximalen Konvolutes der Rattenniere   总被引:5,自引:0,他引:5  
Summary The electrical resistance across the wall of proximal tubules of the rat kidney has been determined in situ. Two different experimental approaches were used. First, the resistance between lumen and interstitium, the so-called effective resistance (R eff) according to cable analysis, was measured. The mean values, as obtained by different methods, scattered between 25 and 100 k, the most probable value being 30–40 k. Second, the passive voltage attenuation along the tubular axis, as described by the length constant () was determined. Applying different methods a value of =86 was derived. With the simple model of cable analysis these results lead to a specific transepithelial resistance of 4.9–5.7 cm2, implying an apparent electrical diameter of the tubular lumen of 26–30 . This diameter is larger than the geometrical one. The value for the specific transephithelial resistance agrees well with results of recent measurements of unidirectional ion fluxes.

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.  相似文献   
963.
AIMS: Fluoroscopy is not available in every endoscopic unit. This situation leads to delays in treatment or to transfer of patients to other centres for stent insertion. We assessed safety and effectiveness of expandable esophageal metal stent placement under endoscopic control without fluoroscopy using a thin gastroscope. PATIENTS AND METHODS: From October 2002 to June 2004, thirty-three consecutive patients have been included for esophageal stent placement under endoscopic control alone with a nasogastroscope (5.9 mm). A proximal release covered stent (Ultraflex; Boston Scientific Microvasive) was used. Indications were malignant esophageal stricture (N = 26), malignant extrinsic compression (N = 2 ) and esophago-respiratory neoplastic fistulae (N = 5). RESULTS: Stent placement using endoscopic control alone was successful in 30/33 (90%) patients. Complications occurred in 11 patients. Early complications (<7 days) included one death from pulmonary embolism, severe retrosternal pain needing transient morphinic treatment (N = 2) and GERD despite antisecretory therapy (N = 1). Late complications included: food impaction (N = 1), tumour overgrowth-related obstruction of the stent (N = 5) and one late esophago-respiratory fistula at 4 months at the proximal end of the stent. Relief of dysphagia was obtained for all patients at 48 hours and dysphagia score decreased from 3.1 before stent to 1.2 at 1 month (P < 0.05). CONCLUSION: Expandable esophageal stents can be accurately and safely placed using endoscopy with a thin gastrosocope. This method obviates the requirement of fluoroscopic access, lacking in many centres, and avoids exposure to X-ray.  相似文献   
964.
Nearly all countries in the world today are burdened with malnutrition, manifesting as undernutrition, micronutrient deficiencies, and/or overweight and obesity. Despite some progress, efforts to alleviate malnutrition are hampered by a shortage in number, skills, and geographic coverage, of a workforce for nutrition. Here, we report the findings of the Castel Gandolfo workshop, a convening of experts from diverse fields in March 2014 to consider how to develop the capacity of a global cadre of nutrition professionals for the post-2015 development era. Workshop participants identified several requirements for developing a workforce for nutrition, including an ability to work as part of a multisectoral team; communication, advocacy, and leadership skills to engage decision makers; and a set of technical skills to address future challenges for nutrition. Other opportunities were highlighted that could immediately contribute to capacity development, including the creation of a consortium to link global North and South universities, online training modules for middle managers, and practical, hands-on experiences for frontline nutrition workers. Institutional and organizational support is needed to enable workshop recommendations on education and training to be effectively implemented and sustained. The findings from the Castel Gandolfo workshop can contribute to the delivery of successful nutrition-relevant actions in the face of mounting external pressures and informing and attaining the forthcoming Sustainable Development Goals.  相似文献   
965.

Background

adrenal tumor-to-liver uptake value (Tmx:Lmx) on 18F-FDG PET/CT is an accurate and reproducible PET parameter in the distinction between benign and malignant adrenal masses. The potential impact of steroid hormone secretion on 18F-FDG uptake is still debatable. The aim of this study was to evaluate this relationship.

Methods

2010–2015: 73 patients who underwent adrenalectomy for adrenocortical tumors [49 secreting/(SA) and 24 non-secreting/(NSA)] were retrospectively included in the study. Fourteen were malignant. All patients underwent hormonal evaluation, functional and anatomical imaging, Weiss scoring and Ki 67 evaluation.

Results

malignant tumors exhibit higher SUVmax than benign tumors (median 7.75 vs 3.06 respectively, p?<?0.001) and Tmx:Lmx was 2.7 vs 1.17 for benign tumors, p?<?0.001.Tmx:Lmx was positively correlated to Weiss score (p?<?0.001).No significant difference was observed for Tmx:Lmx between SA and NSA overall (p?=?0.851), regardless of the subgroup of tumors analyzed. Tmx:Lmx was not correlated to tumor size (p?<?0.508) or 24?h free urinary cortisol level (p?<?0.522).

Conclusions

no correlation was observed between Tmx:Lmx and hormonal status, however the correlation between ratio, malignancy and Weiss score confirm the utility of 18F-FDG PET/CT for the differentiation of benign from malignant adrenal lesions, irrespective of the hormone secretory status of the tumor. 18F-FDG PET/CT is a useful biomarker in the diagnosis of adrenal tumors, regardless of the secretion status.  相似文献   
966.
BACKGROUND: Neuromyelitis optica (NMO) is characterized by optic neuritis and longitudinally extensive acute transverse myelitis. The brain is generally considered healthy in NMO, though very recent studies have demonstrated that magnetic resonance imaging abnormalities may be observed in various brain regions of NMO patients. To date, cognitive functions have never been investigated in NMO. OBJECTIVE: To investigate cognitive functions in a cohort of 30 patients with NMO. DESIGN: Observational, prospective study. PATIENTS: We studied 30 patients with NMO and compared them with 30 patients with multiple sclerosis and 30 healthy controls matched for age, sex, and educational level. Main Outcome Measure We applied a French translation of the Brief Repeatable Battery of Neuropsychological Tests for Multiple Sclerosis and 3 additional tests. RESULTS: Cognitive performance was significantly lower in the NMO and multiple sclerosis groups than in healthy controls for the 2-second (P< .001) and 3-second (P= .001) Paced Auditory Serial Addition Test, the digit symbol modality test (P= .005), word generation (P= .02), and forward (P= .002) and backward (P= .007) digit span test. We did not observe any difference in test performance between NMO and multiple sclerosis patients. We found no differences between the 3 groups for the other tests. We did not find any correlation between clinical, biological, or magnetic resonance imaging results and cognitive dysfunction. CONCLUSIONS: This study confirms the recent concept of a possible brain involvement in NMO. Additional studies are needed to confirm these initial results and to better understand the mechanisms of such abnormalities.  相似文献   
967.
The time course of regression of left ventricular hypertrophy and changes in left ventricular function were followed in 52 middle-aged hypertensive patients divided into two groups: 30 treated with betablockers and 22 with methyldopa. In case of inadequate blood pressure control, diuretics and/or vasodilators were added in both groups. Blood pressure decreased significantly over a three-year follow-up period. The decrease was most pronounced during the first three months. The biggest decrease in posterior wall and interventricular septum thickness was detected by echocardiography also within the first three months. While complete regression of posterior wall hypertrophy was noted within the next three months, interventricular septum thickness decreased steadily over a period of two years. No significant change was seen in the septum in the third year of follow-up. Complete regression of hypertrophy was found in 30 (57.7%) of probands, with no change altogether observed in as few as two patients. Regression was incomplete in 20 (38.4%) obese patients with manifest hypertrophy at the start of the study. Regression of hypertrophy was not associated with left ventricular function deterioration and was observed even after vasodilator administration. There were no differences between the two groups of patients.  相似文献   
968.

Background

Androgen deprivation therapy (ADT) plus docetaxel is the standard of care in fit men with metastatic castration-naive prostate cancer (mCNPC) following results from GETUG-AFU 15, CHAARTED, and STAMPEDE. No data are available on the efficacy of treatments used for metastatic castration-resistant prostate cancer (mCRPC) in men treated upfront with ADT plus docetaxel for mCNPC.

Objective

To investigate the efficacy and tolerance of subsequent treatments in patients treated upfront with chemo-hormonal therapy for mCNPC.

Design, setting, and participants

Retrospective data from the GETUG-AFU 15 phase 3 trial were collected for treatments received for mCRPC.

Outcome measurements and statistical analysis

For the first three lines of salvage treatment for mCRPC we investigated the biochemical progression-free survival, maximum prostate-specific antigen (PSA) decline, overall survival, and tolerance.

Results and limitations

Overall, 245 patients received at least one treatment for mCRPC. For docetaxel used in first-line, a PSA decline ≥50% was observed in 25/66 (38%) and in 4/20 patients (20%) who had received upfront ADT alone and ADT plus docetaxel (p = 0.14). The median biochemical progression-free survival was 6.0 mo (95% confidence interval: 3.6–7.7) and 4.1 mo (95% confidence interval: 1.3–4.9), respectively. For docetaxel used in first- or second-line, a PSA decline ≥50% was observed in 36/80 (45%) and in 4/29 patients (14%) who had received upfront ADT alone and ADT plus docetaxel (p = 0.07). PSA declines ≥50% were observed with bicalutamide in 12/28 (43%) and 4/23 patients (17%) who had received upfront ADT alone and ADT plus docetaxel. Among men treated upfront with ADT plus docetaxel who received abiraterone or enzalutamide for mCRPC, 10/19 patients (53%) achieved a PSA decline ≥50%. Few grade 3–4 events occurred. Study limitations include the observational design and retrospective characteristics of this analysis, without standardized therapeutic salvage protocols, and the limited number of patients in some of the treatment subgroups.

Conclusions

Docetaxel rechallenge following progression to mCRPC after upfront ADT plus docetaxel for mCNPC was active only in a limited number of patients. Available data on abiraterone and enzalutamide support maintained efficacy in this setting. The lack of standardized therapeutic protocols for men developing mCRPC limits the comparability between patients.

Patient summary

Rechallenging docetaxel at castration-resistance was active only in a limited number of patients treated upfront with chemo-hormonal therapy for metastatic castration-naive prostate cancer. Anticancer activity was suggested with abiraterone or enzalutamide in this setting.  相似文献   
969.
Cardiac involvement by intravascular protruding renal cell carcinoma is a well-recognised phenomenon. It most commonly occurs through inferior vena cava extension. Here, we report a case of a lower lobar lung metastasis from renal cell carcinoma involving the left atrium via the inferior pulmonary vein in a patient presenting with von Hippel-Lindau disease. Complete surgical resection was achieved under cardiopulmonary bypass.  相似文献   
970.
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