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31.
Background: In contrast to other volatile anesthetics, xenon produces less cardiovascular depression with fewer fluctuations of various hemodynamic parameters, but reduces cardiac output (CO) in vivo . Besides an increase in left ventricular afterload and reduction of heart rate, an impairment of the right ventricular function might be an additional pathophysiological mechanism for the reduction of CO. Therefore, we used an animal model to study the effects of xenon as a supplemental anesthetic on right ventricular function, especially right ventricular afterload.
Methods: Right ventricular function was monitored with a volumetric pulmonary artery catheter in 11 pigs during general anesthesia with thiopental. Six animals received additional 70% (volume) xenon (equivalent to 0.55 MAC minimum alveolar concentration). Parameters for systolic function, afterload, and preload were calculated at baseline and during 50 min of xenon application, and in a corresponding control group. Significant differences were detected by multivariate analyses of variance for repeated measures.
Results: Xenon reduced CO on average by 30% and increased pulmonary arterial elastance by 60%, which led to a reduction of the right ventricular ejection fraction by 25%. Whereas right ventricular preload remained stable, maximal slope of pulmonary artery pressure and the right ventricular elastance increased. No effect on the ratio of stroke work and end-diastolic volume was found.
Conclusion: The reduction in CO during xenon anesthesia was partly due to an impairment of the right ventricular function, mainly caused by an increased afterload, without an impairment of systolic ventricular function.  相似文献   
32.
33.
A critical analysis of surgery for kidney cancer with vena cava invasion   总被引:1,自引:0,他引:1  
OBJECTIVE: Patients with kidney cancer with venous system involvement are at high risk of cancer recurrence even after the tumor thrombus is successfully removed. This review analyzes the impact on prognosis of the level of involvement of the inferior vena cava (IVC) in renal cell carcinoma (RCC). METHODS: A literature search was done and relevant papers were reviewed. Relatively recent papers as well as large series or papers from expert centers are included in the reference list. RESULTS: Venous invasion in RCC is a major challenge for urologists and patients with venous involvement have a worse prognosis. Although successful removal of a tumor thrombus in the renal vein and IVC may result in improved long-term survival in more than half of the affected patients, a higher level of thrombus appears to be a bad prognosticator for cancer recurrence. A complete IVC thrombectomy, even in the metastatic setting, provides a better quality of life and may prolong survival. CONCLUSIONS: Because surgery still remains the most effective therapeutic option in patients wtih RCC, every attempt should be made to completely remove the IVC thrombus. New targeted agents could be promising as adjuvant therapy in this subset of patients.  相似文献   
34.
OBJECTIVE: To evaluate long-term effectiveness of palatal implants for treatment of mild to moderate obstructive sleep apnea (OSA). STUDY DESIGN: A prospective study of 26 referred patients with a pretreatment apnea-hypopnea index (AHI) of 10 to 30 and a body mass index of < or =30, representing an extended follow-up of a subset of 41 patients enrolled in previous short-term trials. RESULTS: Twenty-one of 26 patients (80.8%) experienced a decrease in AHI. Fifteen of 26 patients (57.7%) had a follow-up AHI <10 at 1 year, whereas 13 patients (50%) had a 50% or greater reduction to an AHI <10 at 1 year. Mean AHI was reduced from 16.5 +/- 4.5 at baseline to 12.5 +/- 10.5 at 3 months (P < 0.014) and to 12.3 +/- 12.7 at 1 year (P < 0.019). CONCLUSIONS: Patients initially responding to palatal implants with improved AHI maintained improvement through long-term follow-up at 1 year.  相似文献   
35.

Background

The failure rate of tendon-bone healing after repair of rotator cuff tears remains high. A variety of biologic- and cell-based therapies aimed at improving rotator cuff healing have been investigated, and stem cell-based techniques have become increasingly more common. However, most studies have focused on the implantation of exogenous cells, which introduces higher risk and cost. We aimed to improve rotator cuff healing by inducing endogenous stem cell mobilization with systemic administration of granulocyte-colony stimulating factor (G-CSF).

Questions/purposes

We asked: (1) Does G-CSF administration increase local cellularity after acute rotator cuff repair? (2) Is there histologic evidence that G-CSF improved organization at the healing enthesis? (3) Does G-CSF administration improve biomechanical properties of the healing supraspinatus tendon-bone complex? (4) Are there micro-MRI-based observations indicating G-CSF-augmented tendon-bone healing?

Methods

After creation of full-thickness supraspinatus tendon defects with immediate repair, 52 rats were randomized to control or G-CSF-treated groups. G-CSF was administered for 5 days after repair and rats were euthanized at 12 or 19 postoperative days. Shoulders were subjected to micro-MR imaging, stress relaxation, and load-to-failure as well as blinded histologic and histomorphometric analyses.

Results

G-CSF-treated animals had significantly higher cellularity composite scores at 12 and 19 days compared with both control (12 days: 7.40 ± 1.14 [confidence interval {CI}, 5.98–8.81] versus 4.50 ± 0.57 [CI, 3.58–5.41], p = 0.038; 19 days: 8.00 ± 1.00 [CI, 6.75–9.24] versus 5.40 ± 0.89 [CI, 4.28–6.51], p = 0.023) and normal animals (12 days: p = 0.029; 19 days: p = 0.019). There was no significant difference between G-CSF-treated animals or control animals in ultimate stress (MPa) and strain, modulus (MPa), or yield stress (MPa) and strain at either 12 days (p = 1.000, p = 0.104, p = 1.000, p = 0.909, and p = 0.483, respectively) or 19 days (p = 0.999, p = 0.964, p = 1.000, p = 0.988, and p = 0.904, respectively). There was no difference in MRI score between G-CSF and control animals at either 12 days (2.7 ± 1.8 [CI, 1.08–4.24] versus 2.3 ± 1.8 [CI, 0.49–4.17], p = 0.623) or 19 days (2.5 ± 1.4 [CI, 1.05–3.94] versus 2.3 ± 1.5 [CI, 0.75–3.91], p = 0.737). G-CSF-treated animals exhibited significantly lower relative bone volume compared with normal animals in the entire humeral head (24.89 ± 3.80 [CI, 20.17–29.60) versus 32.50 ± 2.38 [CI, 29.99–35.01], p = 0.009) and at the supraspinatus insertion (25.67 ± 5.33 [CI, 19.04–32.29] versus 33.36 ± 1.69 [CI, 31.58–35.14], p = 0.027) at 12 days. Further analysis did not reveal any additional significant relationships with respect to regional bone volume or trabecular thickness between groups and time points (p > 0.05).

Clinical Relevance

Postoperative stem cell mobilization agents may be an effective way to enhance rotator cuff repair. Future studies regarding the kinetics of mobilization, the homing capacity of mobilized cells to injured tissues, and the ability of homing cells to participate in regenerative pathways are necessary.  相似文献   
36.
Objectives. To determine whether a 1-cm margin is necessary for cancer control during nephron-sparing surgery (NSS) for renal cell carcinoma (RCC).Methods. A retrospective review of 67 patients who underwent NSS for RCC between 1990 and 2000 was conducted. The data collected included patient demographics, tumor size and location, histologic type and grade, margin status (positive or negative), and the shortest distance of normal parenchyma (in millimeters) around the tumor in the final pathologic specimen. Recurrence was determined from the clinical follow-up, which included physical examination, ultrasonography or computed tomography, and various laboratory tests.Results. Fifty-five cases were performed open and 12 laparoscopically. The mean follow-up was 60 months (range 5 to 124). The mean tumor size was 3.0 cm (range 0.9 to 11.0). Seven patients were found to have a positive margin; 1 died of metastatic RCC, 1 was alive with systemic recurrence, and 5 had no evidence of disease. Of 11 patients with a negative margin distance of less than 1 mm, 9 were recurrence free, 1 had simultaneous local and pulmonary relapse, and the other had pulmonary recurrence only. The remainder of the study patients (n = 49) had negative margins greater than 1 mm, and all were alive without evidence of disease at the last follow-up.Conclusions. This review questions the necessity of a 1-cm margin to prevent recurrence after NSS for RCC. Additional studies to determine the optimal margin distance should be conducted.  相似文献   
37.
This study examined the relative influences of posttraumatic stress disorder (PTSD), other psychopathology, and intimate partner alcohol and drug use on substance‐related problems in U.S. veterans (242 couples, N = 484). Hierarchical regression analyses revealed that partner alcohol and drug use severity explained more variance in veteran alcohol use and drug use (20% and 13%, respectively) than did veteran PTSD, adult antisocial behavior, or depression symptoms combined (6% for veteran alcohol use; 7% for veteran drug use). Findings shed new light on the influence of relationship factors on veteran alcohol and drug use and underscore the importance of couples‐oriented approaches to treating veterans with comorbid PTSD and substance abuse.  相似文献   
38.
Nonhealing chronic wounds in the constantly growing elderly population represent a major public health problem with high socioeconomic burden. Yet, the underlying mechanism of age‐related impairment of wound healing remains elusive. Here, we show that the number of dermal cells expressing cyclin‐dependent kinase inhibitor p21 was elevated upon skin injury, particularly in aged population, in both man and mouse. The nuclear expression of p21 in activated wound fibroblasts delayed the onset of the proliferation phase of wound healing in a p53‐independent manner. Further, the local and transient inhibition of p21 expression by in vivo delivered p21‐targeting siRNA ameliorated the delayed wound healing in aged mice. Our results suggest that the increased number of p21+ wound fibroblasts enforces the age‐related compromised healing, and targeting p21 creates potential clinical avenues to promote wound healing in aged population.  相似文献   
39.
Zusammenfassung In einer Multicenterstudie wurden insgesamt 100 Patienten mit chronischer Urtikaria mittels eines standardisierten Pers?nlichkeitstests (Gie?en-Test), eines standardisierten Beschwerdebogens (Gie?ener Beschwerdebogen) und eines selbstentwickelten Fragebogens zu Symptomatik, Krankengeschichte und Verhalten im Krankheitsschub befragt. Ein knappes Drittel der untersuchten Patienten zeigte erh?hte Depressionswerte und einen hohen Beschwerdedruck, der sich aus K?rpersymptomen zusammensetzt, die im Rahmen einer Depression auftreten k?nnen. Die vorliegenden Ergebnisse erlauben es nicht, eine chronische Urtikaria per se als Somatisierungsst?rung aufzufassen. Da bei einem Drittel der untersuchten Patienten hinsichtlich der Depressivit?t Abweichungen von der Normalbev?lkerung zu finden sind, wird für eine dermatologisch-psychosomatische Simultandiagnostik pl?diert, um den Urtikariapatienten eine der unterschiedlich individuellen Gesamtproblematik entsprechende Behandlung zukommen zu lassen. Eingegangen am 12. Januar 1995 Angenommen am 21. Juni 1995  相似文献   
40.
Background Incidences of malignant melanoma continue to increase in fair‐skinned populations. At least 80% of patients are diagnosed with localized disease and can expect a 5‐year relative survival rate of >90%. Given that the median age at diagnosis of malignant melanoma is 59 years, many patients already suffer chronic diseases when they are confronted with cancer. Objectives The aim of this study was to analyze the effect of additional chronic diseases on health‐related quality of life (QoL) in a population‐based cohort of melanoma patients two years after presumably curative treatment. Methods In 2003–2004, 1085 patients with localized malignant melanoma were recruited from the population‐based Munich Cancer Registry to answer validated QoL questionnaires. Information about comorbidities was also obtained. Factors predicting QoL were analyzed using multivariate logistic regression models. Results A total of 781 patients (72%) returned completed questionnaires, of which 664 (61%) could be included in the analyses. Quality of life scores and differences in subgroups (e.g. sex and age) were essentially similar to those in the general population. Age, number of comorbidities, and several chronic diseases (e.g. heart and kidney disease, diabetes, former depression) were the strongest predicting factors and influenced almost every aspect of QoL. Conclusions Localized malignant melanoma does not worsen QoL per se, compared with QoL in the general population. Comorbidities have similar effects on QoL in malignant melanoma patients as they do in the general population. Therefore, cohorts of patients with localized malignant melanoma can represent a basis for comparisons with other cohorts of cancer patients to determine the respective impacts of cancer‐related and non‐cancer‐related factors on QoL.  相似文献   
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