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81.
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Patients with disorders of sex development (DSD), especially those with gonadal dysgenesis and hypovirilization, are at risk of developing the so-called type II germ cell tumors (GCTs). Both carcinoma in situ and gonadoblastoma (GB) can be the precursor lesion, resulting in a seminomatous or non-seminomatous invasive cancer. SRY mutations residing in the HMG domain are found in 10–15% of 46,XY gonadal dysgenesis cases. This domain contains two nuclear localization signals (NLSs). In this study, we report a unique case of a phenotypical normal woman, diagnosed as a patient with 46,XY gonadal dysgenesis, with an NLS missense mutation, on the basis of the histological diagnosis of a unilateral GB. The normal role of SRY in gonadal development is the upregulation of SOX9 expression. The premalignant lesion of the initially removed gonad was positive for OCT3/4, TSPY and stem cell factor in germ cells, and for FOXL2 in the stromal component (ie, granulosa cells), but not for SOX9. On the basis of these findings, prophylactical gonadectomy of the other gonad was performed, also showing a GB lesion positive for both FOXL2 (ovary) and SOX9 (testis). The identified W70L mutation in the SRY gene resulted in a 50% reduction in the nuclear accumulation of the mutant protein compared with wild type. This likely explains the diminished SOX9 expression, and therefore the lack of proper Sertoli cell differentiation during development. This case shows the value of the proper diagnosis of human GCTs in identification of patients with DSD, which allows subsequent early diagnosis and prevention of the development of an invasive cancer, likely to be treated by chemotherapy at young age.  相似文献   
83.
Stereotactic radiosurgery is related to the history of "radiotherapy" and "stereotactic neurosurgery". The concepts for neurosurgeons and radiooncologists have been changed during the last decade and have also transformed neurosurgery. The gamma knife and the stereotactically modified linear accelerator (LINAC) are radiosurgical equipments to treat predetermined intracranial targets through the intact skull without damaging the surrounding normal brain tissue. These technical developments allow a more precise intracranial lesion control and offer even more conformal dose plans for irregularly shaped lesions. Histological determination by stereotactic biopsy remains the basis for any otherwise undefined intracranial lesion. As a minimal approach, it allows functional preservation, low risk and high sensitivity. Long-term results have been published for various indications. The impact of radiosurgery is presented for the management of gliomas, metastases, brain stem lesions, benign tumours and vascular malformations and selected functional disorders such as trigeminal neuralgia. In AVM''s it can be performed as part of a multimodality strategy including resection or endovascular embolisation. Finally, the technological advances in radiation oncology as well as stereotactic neurosurgery have led to significant improvements in radiosurgical treatment opportunities. Novel indications are currently under investigation. The combination of both, the neurosurgical and the radiooncological expertise, will help to minimize the risk for the patient while achieving a greater treatment success.  相似文献   
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BACKGROUND/AIMS: Diagnosis of pancreatic trauma and its complications may be difficult due to non-specific signs and symptoms and treatment recommendations are not unequivocal. METHODOLOGY: Clinical data of a series of 47 patients with pancreatic trauma were analyzed; most of them were polytraumatized and treated by an interdisciplinary team. RESULTS: The most common causes were traffic accidents and sport injuries with 66% and 15%, respectively. Concomitant injuries were seen in 96% (nonpancreatic intra-abdominal injuries 85% including spleen 38% and liver 34%, extra-abdominal injuries 70%). Concomitant liver injuries were treated conservatively in 31% and operatively in 69% (including hepatic packing in 38%). Concomitant splenic injuries were usually very severe and could be managed conservatively in only 11%. All patients with pancreatic injuries grade III, IV or V (17%) according to the American Association of Surgical Trauma Classification required surgery, endoscopic treatment or interventional radiology. The most common posttraumatic complications were necrotizing pancreatitis (15%), pseudocyst formation (9%), abscesses (6%) and fistulas (4%). CONCLUSIONS: The status of the pancreatic duct is the crucial point for management of pancreatic trauma and should be assessed as early as possible. Treatment has to be tailored to the individual situation, especially in patients with severe concomitant injuries or prolonged course.  相似文献   
85.

Background

Dental caries is one of the primary causes of tooth loss among adults. It is estimated to affect a majority of Americans aged 55 and older, with a disproportionately higher burden in disadvantaged populations. Although a number of treatments are currently in use for caries prevention in adults, evidence for their efficacy and effectiveness is limited.

Methods/Design

The Prevention of Adult Caries Study (PACS) is a multicenter, placebo-controlled, double-blind, randomized clinical trial of the efficacy of a chlorhexidine (10% w/v) dental coating in preventing adult caries. Participants (n = 983) were recruited from four different dental delivery systems serving four diverse communities, including one American Indian population, and were randomized to receive either chlorhexidine or a placebo treatment. The primary outcome is the net caries increment (including non-cavitated lesions) from baseline to 13 months of follow-up. A cost-effectiveness analysis also will be considered.

Discussion

This new dental treatment, if efficacious and approved for use by the Food and Drug Administration (FDA), would become a new in-office, anti-microbial agent for the prevention of adult caries in the United States.

Trial Registration Number

NCT00357877  相似文献   
86.
BACKGROUND: Unlike colon surgery, gastric surgery developed only slowly. Standardized stomach surgery can be said to have begun in 1881 with Billroth's successful gastric resection. The Department of Surgery in Graz was involved in the development and then rapid dissemination of gastric surgery, with respect to both ulcer and cancer surgery. Since the introduction of the modern proton-pump inhibitors, surgery for gastric ulcers today is mainly limited to the treatment of complications. In spite of the worldwide decrease in the incidence of stomach cancer, it is still of great clinical importance in Austria. METHODS: The development of gastric surgery at the Department of Surgery in Graz is presented on the basis of the literature. RESULTS: Still today, the only curative option for stomach cancer is radical surgical removal with lymphadenectomy as indicated. In the period of January 1, 1994 to December 31, 2004, 341 patients with stomach cancer were treated at the Division of General Surgery in Graz; 265 of them could be operated and the average 5-year survival rate was 36% without regard to tumor stage. CONCLUSIONS: It may be said that more than one hundred years of development have led to the standardization and optimization of gastric surgery, and that the contributions of surgeons in Austria and in Graz were considerable.  相似文献   
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A 59-year-old white woman with temporal arteritis developed progressive renal failure. Renal biopsy results showed focal and segmental necrotizing glomerulonephritis; furthermore, giant cells were present in the destructed vessel walls. Immunosuppressive therapy did not prevent terminal renal failure. This case shows that renal involvement may be a feature of temporal arteritis.  相似文献   
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