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991.
992.
PURPOSE: Recent advances in laparoscopic surgery as well as increasing experience with these techniques have led to the selection of laparoscopic surgery for many urological procedures. A lesser number of pediatric laparoscopic surgical studies have been reported. Few pediatric comparative laparoscopic versus open surgical procedure studies have been published. We compared 2 groups of similar pediatric patients who underwent partial nephrectomy via the laparoscopic or open technique. MATERIALS AND METHODS: A total of 22 consecutive partial nephrectomies were performed in pediatric patients 3 months to 15 years old. Of these procedures 11 chosen according to surgeon preference were performed laparoscopically and 11 were done by the open technique. Clinical data were obtained by chart review and compared retrospectively in the 2 groups. Demographic data, operative time and blood loss, the perioperative complication rate, hospital stay and costs, postoperative analgesic use and followup findings were compared. RESULTS: Mean operative time in the laparoscopic and open groups was 200.4 and 113.5 minutes, respectively (p <0.0005). Blood loss was less than 50 cc in all patients. In the laparoscopic and open groups mean hospital stay was 25.5 and 32.6 hours (p = 0.068), and mean cost was $6,125 and $4,244 (p = 0.016), respectively. Patients in the laparoscopic group required fewer doses of analgesics than those who underwent open surgery (mean 10.9 versus 21, p = 0.041). CONCLUSIONS: Our findings show that increased operative time and costs are disadvantages of pediatric laparoscopic nephrectomy compared with open techniques. Conversely decreased hospital stay, lower analgesic requirements and cosmesis support the use of laparoscopy for pediatric partial nephrectomy. These differences must be considered when deciding which technique is best for overall patient care.  相似文献   
993.

Background and purpose

Schnitzler syndrome is characterized by chronic urticaria, monoclonal gammopathy, and a risk of developing lymphoproliferative disorders. Patients frequently present with bone pain, fever, arthralgia, and lymphadenopathy. The purpose of this study is to retrospectively review and evaluate potentially attributable imaging abnormalities in a series of patients with clinically diagnosed Schnitzler syndrome.

Materials and methods

Clinical and pathological chart review identified 22 patients meeting Strasbourg criteria for Schnitzler syndrome. Imaging of these patients was retrospectively reviewed by a musculoskeletal radiologist and a radiology fellow to determine and characterize significant “positive” findings that could potentially be attributed to their primary disease process.

Results

Evidence of abnormal bone remodeling was present in 64 % (14/22) of patients with 40 bone abnormalities. Lesions were predominantly or entirely sclerotic and most commonly involved the distal femora (n?=?11), proximal tibiae (nine), and innominate bones (six). Patterns of involvement were variable, but typically eccentrically intramedullary, cortical, and juxta-articular. Skeletal surveys and targeted radiographs identified only 37 % (10/27) of abnormal bones subsequently “positive” by additional modalities. PET and bone scans were all positive in patients with bone sclerosis (13/13 and 17/17 bone sites, respectively).

Conclusions

Schnitzler syndrome often presents with characteristic osteosclerosis, most commonly around the knees and in the pelvis. In patients with a suggestive clinical history, the radiologist could direct an appropriate imaging strategy or might to be the first to suggest the diagnosis. Bone scan may be the most appropriate initial screening tool in suspected cases.  相似文献   
994.

Background

Prognostic factors for uterine leiomyosarcomas are not well established. Although most tumors are associated with poor prognosis even when apparently confined to the uterus (stage I), some cases that exhibited morphologic features of malignancy had prolonged survival.

Methods

Using tissue microarrays of 84 uterine leiomyosarcomas, we investigated conventional clinico-pathologic parameters, including International Federation of Gynecology and Obstetrics (FIGO) stage, together with expression of Ki67, p53, p16, and Bcl-2, attempting to distinguish leiomyosarcomas with different prognosis. The rate of CD163 immunoreactive tumor macrophages was also investigated.

Results

Tumor size and mitotic index were significant prognostic factors by univariate (p = 0.018 and p = 0.003, respectively) and multivariate (p = 0.006 and p = 0.001) analyses. Of the biomarkers investigated, only Ki67 immunoreaction was significant by univariate analysis and was associated with adverse prognosis (p = 0.01). However, combination of tumor size, mitotic index, Ki67, and Bcl-2 worked even better. Using these 4 parameters, unsupervised hierarchical clustering identified 2 groups of tumors with different prognosis (p = 0.001): group 1 consisted mostly of smaller leiomyosarcomas (< 10 cm) with mitotic index < 20 MF/10 HPF, negative Ki67, and positive or negative Bcl-2 immunostaining. These tumors were associated with better prognosis. In contrast, group 2 leiomyosarcomas which were mostly ≥ 10 cm in diameter had higher mitotic index (≥ 20 MF/10 HPF), and were positive for Ki67 and negative for Bcl-2 had worse prognosis. Also, the number of CD163-macrophages was greater in group 2 than group 1 (p = 0.007).

Conclusions

Tumor size and mitotic index are morphologic predictors of malignancy in uterine leiomyosarcomas. Combination of tumor size, mitotic index, Ki67, and Bcl-2 protein expression allows distinguishing 2 groups of leiomyosarcomas with different survival. Leiomyosarcomas associated with poor outcome had a higher number of CD163 stromal macrophages.  相似文献   
995.
996.
We examine the heterogeneity among current and former smokers categorized by 'stage of change' with respect to their perceptions about tobacco and tobacco control. Current and former smokers (n = 846) from a general population sample of adults in Ontario, Canada, were subdivided according to the stages of change categories (precontemplation, contemplation, preparation, action, maintenance, and termination) and compared on measures of knowledge, attitudes, and support. Multivariate analyses were conducted adjusting for sociodemographic covariates. Adjusted overall increases across the six stages were observed for seven of eight knowledge items and for all attitude and support items. Among current smokers, adjusted increases across the three stages were detected for a majority of items. However, statistically significant differences from one stage to the next, across all three current smoker stages, were detected only for one item. Among former smokers, adjusted increases across the three stages were observed for a minority of items. The stages of change classification was useful for differentiating subgroups of current smokers with regard to knowledge, attitudes, and support for tobacco control measures.  相似文献   
997.
Space motion sickness (SMS) is a problem during the first 72 h of space flight and during transitions from different gravity environments. There currently are no effective drug countermeasures for SMS that also accommodate the retention of optimal cognitive function. This creates a dilemma for astronauts because cognitive skills are particularly important during gravity transitions (e.g., take-off and landing). To quantify the cognitive side effects of potential drug countermeasures, an automated delayed matching-to-sample (DMTS) procedure was used to assess visual working memory before and after drug countermeasures (meclizine 25 mg, scopolamine 0.4 mg, promethazine 25 mg, or lorazepam 1 mg, given orally approximately 45 min prior to testing) and/or the induction of SMS by vestibular stimulation in a rotary chair (spinning). Sixty-seven normal healthy volunteers (mean age, in years, 26.6±4.8 S.D.; 24 females and 43 males) each participated in two test sessions, one ‘off’ drug and one ‘on’ drug. Spinning by itself significantly decreased task accuracy (Acc) and choice response speed, especially at longer recall delays. Meclizine alone had no effect on Acc or speed with or without spinning. Scopolamine alone decreased Acc, and with spinning, slowed speed. Promethazine alone had no adverse effect, but combined with spinning, decreased Acc and speed. Lorazepam alone decreased speed, and with spinning, decreased Acc. The data suggest that, at clinically useful doses, the rank order of the drugs with the best cognitive profiles is meclizine>scopolamine>promethazine>lorazepam.  相似文献   
998.
Non-functioning pituitary adenomas (NFPAs) may be locally invasive. Surgery is a treatment option, but unlike the case for functional pituitary adenomas, there are almost no drug treatments available for NFPAs. Markers of invasiveness are needed to guide therapeutic decision-making and identify potential adjuvant drugs. Owing to the highly heterogeneous nature of NFPAs, little is known regarding the subtype-specific gene expression profiles associated with invasiveness. To identify important biomarkers of invasiveness, we selected 23 null cell adenomas and 20 oncocytomas. These tumors were classified as invasive or non-invasive adenomas based on magnetic resonance imaging, pathology slides and surgical findings. Firstly, we observed that there were significant differences in expression between invasive (n = 3) and non-invasive (n = 4) adenomas by gene expression microarray. A total of 1,188 genes were differentially expressed in the invasive and non-invasive adenomas. Among these 1,188 genes, 578 were upregulated and 610 were downregulated in invasive adenomas. Secondly, the expression of ENC1, which displayed the significant alterations, was further confirmed by qRT-PCR and Western blot analysis in all 43 tumor samples and three normal pituitary glands. Low levels of ENC1 were found in tumor samples, while high levels were detected in normal pituitary glands. Interestingly, the ENC1 expression level was low in invasive null cell adenomas compared with non-invasive adenomas, but this relationship was not observed in invasive oncocytomas. Immunohistochemistry also demonstrated that the staining of ENC1 was different between invasive and non-invasive null cell adenomas. In addition, bioinformatics studies, including gene ontology and protein interaction analyses, were also performed to better understand the critical role of ENC1 in the development and progression of null cell adenomas and oncocytomas. Consequently, ENC1 may be an important biomarker for null cell adenomas and oncocytomas, and it is specific to invasive null cell adenomas.  相似文献   
999.
1000.
We report the case history of a woman with a germ line mutation in the TP53 gene who developed 17 separate primary tumours. The incidence of new tumours rose steeply after adjuvant tamoxifen treatment for breast cancer and adjuvant vaginal vault radiotherapy for endometrial cancer. This increase could be due to cumulative genetic damage from environmental agents and the fact that the patient lived to the relatively late age of 60 years, or to a high inherent deleterious somatic mutation rate, which could represent the inability of cells from patients with TP53 mutations to repair therapy-induced genetic damage.  相似文献   
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