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31.
To investigate possible effects of corticosteroids on polyp formation and local bacterial colonization, pneumococcal sinusitis was experimentally induced in rabbits pretreated with betamethasone or saline. After 7 days, macroscopic polyps were counted post-mortem and on histologic slides after serial sectioning. Histologic sections were also examined with light microscopy. Macroscopic polyps were significantly fewer in animals given betamethasone, while there was no difference regarding the number of microscopic polyps. Ingrowth of pathogenic microorganisms was found in five of eight rabbits given placebo but in none of the animals treated with corticosteroids (P < 0.05). The reduced number of pathogenic strains in these animals may be explained by a better-preserved local host defense. The lower number of macroscopic polyps in the same animals could be because of a delayed mucosal repair and subsequent polyp formation.  相似文献   
32.
ObjectiveThe Gynecologic Oncology Group (GOG) performed a detailed analysis of p53 overexpression in previously-untreated women with invasive early or advanced stage epithelial ovarian cancer (EOC).MethodsWomen were eligible for the study if they provided a tumor block for translational research and participated in either GOG-157, a randomized phase III trial of three versus (vs.) six cycles of paclitaxel + carboplatin in high-risk, early stage EOC, or GOG-111, a randomized phase III trial of cyclophosphamide + cisplatin vs. paclitaxel + cisplatin in suboptimally-resected, advanced stage EOC. The N-terminal DO-7 p53 antibody was used to examine the expression of the major normal and mutant p53-isoforms. p53 overexpression was defined as ≥ 10% tumor cells exhibiting nuclear staining.Resultsp53 was overexpressed in 51% (73/143) and 66% (90/136) of cases in the GOG-157 and GOG-111 cohorts, respectively. In the GOG-157 cohort, p53 overexpression was not associated with any clinical characteristics or overall survival (OS) but was associated with worse progression-free survival (PFS) (logrank test: p = 0.013; unadjusted Cox modeling: p = 0.015). In the GOG-111 cohort, p53 overexpression was associated with GOG performance status (p = 0.018) and grade (p = 0.003), but not with age, stage, cell type or with tumor response and disease status after primary chemotherapy, PFS or OS. Adjusted Cox regression modeling demonstrated that p53 overexpression was not an independent prognostic factor for PFS or OS in either cohort.Conclusionsp53 overexpression assessed by DO-7 immunostaining is common in early and advanced stage EOC, but has limited prognostic value in women treated with surgical staging and platinum-based combination chemotherapy.  相似文献   
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34.
Originally applied to alpha oscillations in the 1970s, microstate (MS) analysis has since been used to decompose mainly broadband electroencephalogram (EEG) signals (e.g., 1–40 Hz). We hypothesised that MS decomposition within separate, narrow frequency bands could provide more fine‐grained information for capturing the spatio‐temporal complexity of multichannel EEG. In this study, using a large open‐access dataset (n = 203), we first filtered EEG recordings into four classical frequency bands (delta, theta, alpha and beta) and thereafter compared their individual MS segmentations using mutual information as well as traditional MS measures (e.g., mean duration and time coverage). Firstly, we confirmed that MS topographies were spatially equivalent across all frequencies, matching the canonical broadband maps (A, B, C, D and C′). Interestingly, however, we observed strong informational independence of MS temporal sequences between spectral bands, together with significant divergence in traditional MS measures. For example, relative to broadband, alpha/beta band dynamics displayed greater time coverage of maps A and B, while map D was more prevalent in delta/theta bands. Moreover, using a frequency‐specific MS taxonomy (e.g., ϴA and αC), we were able to predict the eyes‐open versus eyes‐closed behavioural state significantly better using alpha‐band MS features compared with broadband ones (80 vs. 73% accuracy). Overall, our findings demonstrate the value and validity of spectrally specific MS analyses, which may prove useful for identifying new neural mechanisms in fundamental research and/or for biomarker discovery in clinical populations.  相似文献   
35.
Radiation-associated angiosarcoma of the breast (RAASB) is a rare and aggressive malignancy occurring after radiation therapy as part of breast cancer treatment. RAASB usually presents several years after prior radiation and typically involves the skin with or without involvement of the parenchyma. Most RAASB are detected as cutaneous changes on physical exam. Herein, we present a unique case of a clinically occult RAASB diagnosed as non-mass enhancement on annual surveillance breast MRI.  相似文献   
36.
Immune checkpoint inhibitors (ICIs) have been associated with neurological immune related adverse events (irAE-N) and patients with ICI toxicity may present with neurological or ocular symptoms. Furthermore, patients on ICI may initially present to oncology or neurology. We report a case series of 3 patients treated with ICIs presenting with diplopia or ptosis, found to have concurrent myocarditis in addition to immune-related myopathy (irMyopathy) or myasthenia gravis (irMG). None of the patients described cardiac symptoms, underscoring the importance of screening for myocarditis in patients presenting with diplopia and/or other neuromuscular symptoms which may suggest either irMyopathy or irMG.  相似文献   
37.

Purpose

Transanal endoscopic microsurgery (TEM) procedure could potentially influence the development of fecal incontinence later in life. The aim of our study was to assess long-term functional outcomes after TEM and to determine possible variables related to incontinence.

Methods

Patients, enrolled in a prospectively collected TEM operation database, were interviewed using a postal questionnaire. The questionnaire consisted of EuroQol (EQ)-5D-5L quality of life questionnaire, Wexner fecal incontinence grading scale, and additional questions about other perianal operations and obstetric history for women. We divided patients into two groups: no or minor fecal incontinence (Wexner score of 2 and less) and non-minor incontinence (Wexner score of 3 or more).

Results

One hundred thirty-two patients were included in the study. Patients’ median follow-up time was 96 (12–168) months from their operation. Thirty-eight patients (28.8%) reported Wexner score of 3 or more, and they reported significantly worse quality of life in all tested life spheres. They were older at the time of the operation (63 (18–82) vs. 68 (50–89) years; p?=?0.004), underwent longer operations (50 (10–140) vs. 60 (15–210) min; p?=?0.017), and more often were operated for malignant lesions (17 (18.3%) vs. 14 (36.8%); p?=?0.040). Older age at the time of operation was an independent risk factor in multivariate model (OR 1.057, 95% CI 1.010–1.106; p?=?0.016).

Conclusions

Fecal incontinence after TEM is more common than thought previously, resulting in significantly impaired quality of life. Older age at the time of operation was an independent risk factor for developing significant fecal incontinence.
  相似文献   
38.
39.
The effect of three peptides, galanin, sulfated cholecystokinin octapeptide, and neurotensin (NT), was studied on acutely extirpated rat dorsal root ganglia (DRGs) in vitro with intracellular recording techniques. Both normal and peripherally axotomized DRGs were analyzed, and recordings were made from C-type (small) and A-type (large) neurons. Galanin and sulfated cholecystokinin octapeptide, with one exception, had no effect on normal C- and A-type neurons but caused an inward current in both types of neurons after sciatic nerve cut. In normal rats, NT caused an outward current in C-type neurons and an inward current in A-type neurons. After sciatic nerve cut, NT only caused an inward current in both C- and A-type neurons. These results suggest that (i) normal DRG neurons express receptors on their soma for some but not all peptides studied, (ii) C- and A-type neurons can have different types of receptors, and (iii) peripheral nerve injury can change the receptor phenotype of both C- and A-type neurons and may have differential effects on these neuron types.  相似文献   
40.
Natriuretic peptides in unstable coronary artery disease.   总被引:1,自引:0,他引:1  
Patients with unstable coronary artery disease (CAD), i.e., unstable angina or non-ST-elevation myocardial infarction, vary widely in clinical presentation, prognosis and response to treatment. To select appropriate therapy, early risk stratification has become increasingly important. This review focuses on the emerging role of natriuretic peptides in the early assessment of patients with unstable CAD. We conclude that levels of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are strongly associated to mortality and the risk of future congestive heart failure, and carry important prognostic information independent from previously known risk factors in unstable CAD. There are some data indicating that these markers can also be helpful in the selection of appropriate therapy in these patients but further studies are needed. Before a routine use of BNP or NT-proBNP in unstable CAD can be recommended, the cost-effectiveness of adding these new markers to the currently routine markers and their impact on selection of treatment needs further evaluation.  相似文献   
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