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991.

Background

Lymph node status is an important prognostic factor and a criterion for adjuvant therapy in uterine cancers. While detection of micrometastases by ultrastaging techniques is correlated to prognosis in several other cancers, this remains a matter of debate for uterine cancers. The objective of this review on sentinel nodes (SN) in uterine cancers was to determine the contribution of ultrastaging to detect micrometastases.

Methods

Review of the English literature on SN procedure in cervical and endometrial cancers and histological techniques including hematoxylin and eosin (H&E) staining, serial sectioning, immunohistochemistry (IHC) and molecular techniques to detect micrometastases.

Results

In both cervical and endometrial cancers, H&E and IHC appeared insufficient to detect micrometastases. In cervical cancer, using H&E, serial sectioning and IHC, the rate of macrometastases varied between 7.1% and 36.3% with a mean value of 25.8%. The percentage of women with micrometastases ranged from 0% and 47.4% with a mean value of 28.3%. In endometrial cancer, the rate of macrometastases varied from 0% to 22%. Using H&E, serial sectioning and IHC, the rate of micrometastases varied from 0% to 15% with a mean value of 5.8%. In both cervical and endometrial cancers, data on the contribution of molecular techniques to detect micrometastases are insufficient to clarify their role in SN ultrastaging.

Conclusion

In uterine cancers, H&E, serial sectioning and IHC appears the best histological combined technique to detect micrometastases. Although accumulating data have proved the relation between the risk of recurrence and the presence of micrometastases, their clinical implications on indications for adjuvant therapy has to be clarified.  相似文献   
992.

Aim.

Improving quality of care for cancer patients requires insight into their specific wishes, needs, and preferences concerning cancer care. The aim of this study was to explore the impact of gender on cancer patients'' needs and preferences.

Patients and Methods.

Data were obtained from 386 questionnaires assessing cancer patients'' preferences for health care. Multivariate regression analyses were performed with data obtained from medical oncology patients treated in seven Dutch hospitals, using the scales of the questionnaire as dependent variables.

Results.

Patients rated safety, expertise, performance, and attitude of physicians and nurses highest on their list of preferences. There were significant differences between male and female patients concerning preferences in health care in 15 of the 21 scales and in two of the eight single items. Without exception, women found the care aspects mentioned in these scales and items more important than men. Multivariate regression analysis showed that, of all the patient- and disease-related factors, gender was the most important independent predictor of patient preferences.

Conclusion.

Gender impacts cancer patients'' needs and preferences and should be taken into account for optimal cancer care. Cancer care might be tailored toward gender, for example, with regard to the means and extent of communication, manner and extent of support, counseling and rehabilitation, consultation length, and physician assignment. The results of this study may guide health care professionals and organizations to develop a gender-specific health care approach to further improve cancer patient–centered care.  相似文献   
993.
Context: This article presents the main results from a large‐scale analytical systematic review on knowledge exchange interventions at the organizational and policymaking levels. The review integrated two broad traditions, one roughly focused on the use of social science research results and the other focused on policymaking and lobbying processes. Methods: Data collection was done using systematic snowball sampling. First, we used prospective snowballing to identify all documents citing any of a set of thirty‐three seminal papers. This process identified 4,102 documents, 102 of which were retained for in‐depth analysis. The bibliographies of these 102 documents were merged and used to identify retrospectively all articles cited five times or more and all books cited seven times or more. All together, 205 documents were analyzed. To develop an integrated model, the data were synthesized using an analytical approach. Findings: This article developed integrated conceptualizations of the forms of collective knowledge exchange systems, the nature of the knowledge exchanged, and the definition of collective‐level use. This literature synthesis is organized around three dimensions of context: level of polarization (politics), cost‐sharing equilibrium (economics), and institutionalized structures of communication (social structuring). Conclusions: The model developed here suggests that research is unlikely to provide context‐independent evidence for the intrinsic efficacy of knowledge exchange strategies. To design a knowledge exchange intervention to maximize knowledge use, a detailed analysis of the context could use the kind of framework developed here.  相似文献   
994.

Background  

Parathyroidectomy (PTX), either subtotal or total with forearm autografting, is a well-established treatment for refractory renal hyperparathyroidism (RHPT). However, 20–30% of patients develop persistent or recurrent disease. Obtaining accurate localization before reoperation is difficult.  相似文献   
995.

Purpose  

Major depressive disorder (MDD) has been related to both a dysfunctional γ-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABAA-benzodiazepine receptor in depressed patients or in relation to antidepressant treatment.  相似文献   
996.

Aims

Radiotherapy of small laboratory animals (SLA) is often not as precisely applied as in humans. Here we describe the use of a dedicated SLA magnetic resonance imaging (MRI) scanner for precise tumor volumetry, radiotherapy treatment planning, and diagnostic imaging in order to make the experiments more accurate.

Methods and materials

Different human cancer cells were injected at the lower trunk of pfp/rag2 and SCID mice to allow for local tumor growth. Data from cross sectional MRI scans were transferred to a clinical treatment planning system (TPS) for humans. Manual palpation of the tumor size was compared with calculated tumor size of the TPS and with tumor weight at necropsy. As a feasibility study MRI based treatment plans were calculated for a clinical 6 MV linear accelerator using a micro multileaf collimator (μMLC). In addition, diagnostic MRI scans were used to investigate animals which did clinical poorly during the study.

Results

MRI is superior in precise tumor volume definition whereas manual palpation underestimates their size. Cross sectional MRI allow for treatment planning so that conformal irradiation of mice with a clinical linear accelerator using a μMLC is in principle feasible. Several internal pathologies were detected during the experiment using the dedicated scanner.

Conclusion

MRI is a key technology for precise radiotherapy of SLA. The scanning protocols provided are suited for tumor volumetry, treatment planning, and diagnostic imaging.  相似文献   
997.
Most monoclonal antibodies in oncology are administered in body–size‐based dosing schedules. This is believed to correct for variability in both drug distribution and elimination between patients. However, monoclonal antibodies typically distribute to the blood plasma and extracellular fluids only, which increase less than proportionally with the increase in body weight. Elimination takes place via proteolytic catabolism, a nonspecific immunoglobulin G elimination pathway, and intracellular degradation after binding to the target. The latter is the primary route of elimination and is related to target expression levels rather than body size. Taken together, the minor effects of body size on distribution and elimination of monoclonal antibodies and their usually wide therapeutic window do not support body–size‐based dosing. We evaluated effects of body weight on volume of distribution and clearance of monoclonal antibodies in oncology and show that a fixed dose for most of these drugs is justified based on pharmacokinetics. A survey of the savings after fixed dosing of monoclonal antibodies at our hospital showed that fixed dosing can reduce costs of health care, especially when pooling of preparations is not possible (which is often the case in smaller hospitals). In conclusion, based on pharmacokinetic parameters of monoclonal antibodies, there is a rationale for fixed dosing of these drugs in oncology. Therefore, we believe that fixed dosing is justified and can improve efficiency of the compounding. Moreover, drug spillage can be reduced and medication errors may become less likely.

Implications for Practice

The currently available knowledge of elimination of monoclonal antibodies combined with the publicly available data from clinical trials and extensive population pharmacokinetic (PopPK) modeling justifies fixed dosing. Interpatient variation in exposure is comparable after body weight and fixed dosing and most monoclonal antibodies show relatively flat dose‐response relationships. For monoclonal antibodies, this results in wide therapeutic windows and no reduced clinical efficacy after fixed dosing. Therefore, we believe that fixed dosing at a well‐selected dose can increase medication safety and help in reduction of costs of health care without the loss of efficacy or safety margins.  相似文献   
998.
999.
Prosthetic valve obstruction (PVO) is a rare but feared complication of mechanical valve replacement. Diagnostic evaluation should focus on differentiating prosthetic valve thrombosis (PVT) from pannus formation, as their treatment options differ. History of sub-optimal anti-coagulation and post-op time course to development of PVO are useful clinical characteristics in differentiating thrombus from pannus formation. Treatment of PVT is influenced by the patient’s symptoms, valve location, degree of obstruction and thrombus size and may include thrombolysis or surgical intervention. Alternatively, pannus formation requires surgical intervention. The purpose of this article is to review the pathophysiology, epidemiology, diagnostic approach and treatment options for aortic and mitral valve PVO.  相似文献   
1000.
OBJECTIVE: Systemic lupus erythematosus (SLE) is an immune-mediated disease that particularly affects the kidneys, causing lupus nephritis. In experimental mouse models, lupus nephritis can be mimicked by inducing a chimeric state through the injection of parental T cells in offspring. In humans, pregnancy-induced chimerism may play a role in the pathogenesis of autoimmune diseases such as SLE, but it is likely that only certain chimeric cells have pathogenic potential. In this study, we investigated whether the distribution of chimeric cells is different in the kidneys of women with SLE from that in normal kidneys, and we examined the phenotype of chimeric cells in women with SLE. METHODS: The presence of chimeric cells was investigated by in situ hybridization targeting the Y chromosome in 57 renal biopsy samples from 49 women with lupus nephritis. Fifty-one kidney autopsy specimens without histomorphologic lesions served as controls. Double-staining for the Y chromosome in combination with CD3 and CD34 markers was performed in 5 kidney specimens with lupus nephritis to identify the phenotype of the chimeric cells. RESULTS: Y chromosome-positive cells were found in 27 of 49 patients with lupus nephritis and in 13 of 51 normal controls (P < 0.01). Both CD3+ and CD34+ chimeric cells were identified in lupus nephritis kidney specimens. CONCLUSION: Chimeric cells are present significantly more often in kidneys with lupus nephritis than in normal kidneys, and some of these chimeric cells are T cells. This finding is interesting in light of experimental models demonstrating that lupus nephritis is initiated by chimeric T cells.  相似文献   
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