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101.
Prostate cancer is one of the principal medical problems facing the male population in developed countries with an increasing need for sophisticated imaging techniques and risk-adapted treatment options. This article presents an overview of the current imaging procedures in the diagnosis of locally advanced prostate cancer. Apart from conventional gray-scale transrectal ultrasound (TRUS) as the most frequently used primary imaging modality we describe computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). CT and MRI not only allow assessment of prostate anatomy but also a specific evaluation of the pelvic region. Color-coded and contrast-enhanced ultrasound, real-time elastography, dynamic contrast enhancement in MR imaging, diffusion imaging, and MR spectroscopy may lead to a clinically relevant improvement in the diagnosis of prostate cancer. While bone scintigraphy with (99m)Tc-bisphosphonates is still the method of choice in the evaluation of bone metastasis, whole-body MRI and PET using (18)F-NaF, (18)F-FDG, (11)C-choline, (11)C-acetate, and (18)F-choline as tracers achieve higher sensitivities.  相似文献   
102.
A large variety of approaches are described for standard total hip arthroplasty. All of them are technically based on three different approaches: anterior, anterolateral, or posterior. In recent hip resurfacing, the posterior approach is common, due to large instruments used to ream the femur. Better exposure of the acetabulum is achieved by the posterior approach, but this technique puts the important extraosseous blood supply to the femoral head at risk. The anterior approach preserves blood supply and gives better options to treat the femoroacetabular impingement. If specific surgical modifications and instruments designed for minimally invasive surgery are used, hip resurfacing can be performed with an anterolateral technique. Excellent functional and clinical outcomes have been reported after all three approaches.  相似文献   
103.
Retroperitoneoskopische Nierenchirurgie   总被引:1,自引:0,他引:1  
Retroperitoneoscopy enables quick, simple, and direct access to the retroperitoneal cavity. We describe our operative technique and discuss the advantages and disadvantages of retroperitoneoscopy. We report on our experience with this operative technique after 360 procedures: nephrectomy, partial nephrectomy, living donor nephrectomy, cryotherapy of renal tumors, pyeloplasty, adrenalectomy, and further operations. In addition, we discuss indications that are suitable for beginners to retroperitoneoscopy and some topics that require special attention.  相似文献   
104.
Heparin-induced thrombocytopenia (HIT) represents a serious side effect caused by an atypical immune response to platelet factor 4 leading to platelet activation and thrombin formation. These patients are at high risk of thromboembolism, with a rapid drop in platelet count between days 5 and 14 after the initiation of heparin treatment. In single cases, especially after major surgery, platelet count reduction might be absent or hidden by preceding thrombocytosis. Different clinical manifestations of HIT include unspecific skin reactions with potential necrosis at the site of heparin injection, mostly after the application of unfractionated heparin but also with low molecular weight heparin. In heparin-induced skin necrosis, administration of unfractionated or low molecular weight heparin is contraindicated and heparin therapy should be stopped immediately. Instead, an alternative anticoagulant in the form of a direct thrombin inhibitor such as argatroban, and respectively lepirudin, or danaparoid sodium must be administered. Due to frequent misinterpretations of heparin-induced unspecific skin reactions, especially in the absence of thrombocytopenia, we present two case reports which should increase the awareness of HIT’s various clinical pictures.  相似文献   
105.
A review of the current literature provides new scientific insights into the diagnosis, prognosis and novel molecular targets for bladder cancer. The new WHO classification refines our staging system and influences treatment options. International clinical databases provide new tools for calculating the individual risk for bladder cancer recurrence and progression. Systematic gene cluster analysis defines multimarker panels that can serve as robust predictors of outcome. Discoveries of new signaling pathways in bladder cancer are leading to novel molecular targets for innovative therapies.  相似文献   
106.
Early evaluation of the prognosis after multiple trauma or major surgery is known to be difficult. Inflammatory markers can be used in attempts to identify patients who are at risk of developing posttraumatic complications. The inflammatory mediators that are most widely used in ICUs are C-reactive protein (CRP), cytokines (TNF-α, IL-6, IL-8, IL-10) and procalcitonin (PCT), IL-6 and PCT apparently being the most reliable immune markers for the assessment of a patient’s clinical status. However, no single inflammatory parameter alone can predict the clinical course and outcome of multiple trauma patients. This is also hardly surprising, in view of the complexities of pathologic processes and of molecular mechanisms and gender-dependent factors. Therefore, laboratory markers (e.g. lactate, pH), clinical assessment and inflammatory parameters should all be used in evaluation of the prognosis and the clinical status of multiply traumatised patients.  相似文献   
107.
Background The standard treatment for epidermoid carcinoma of the anal canal consists of combined radiation and chemotherapy. For patients who present with persistent or locally recurrent disease, salvage abdominoperineal resection is the treatment of choice. The purpose of this study is to review our experience with salvage surgery in this group of patients. Methods From 1990–2002, 31 patients underwent radical salvage surgery with curative intent after failure of initial sphincter-conserving therapy, and the medical records of these patients were retrospectively reviewed. Clinicopathologic variables were determined and comparisons performed with the Cox proportional hazards model. Survival was calculated by the Kaplan–Meier method. Results Eleven patients underwent radical salvage surgery for persistent disease and 20 patients for recurrent disease. The median follow-up time was 29 months. The actuarial 5-year overall survival was 64%. Twelve patients developed recurrent disease after radical salvage surgery. Patients who received an initial radiation dose of less than 55 Gy had a significantly worse survival than those who received at least 55 Gy as part of their initial treatment (5-year overall survival 37.5% vs. 75%; age-adjusted hazard ratio 8.2 [95% CI: 1.1–59.8], P = .037). The presence of positive lymph nodes at presentation also adversely affected survival (P < .05). Factors that were not found to have an impact on survival included the presence of persistent versus recurrent disease, tumor (T) stage, and margin status of resection. Conclusions Long-term survival following salvage surgery for persistent or locally recurrent epidermoid carcinoma of the anal canal can be achieved in the majority of patients. However, patients who initially present with node-positive disease and patients who receive a radiation dose of less than 55 Gy as part of their initial chemoradiation therapy regimen have a worse prognosis after radical salvage surgery.  相似文献   
108.

Background

Ischemia and reperfusion (I/R) lead to cellular damage. A disturbance of testicular perfusion occurs during the therapy of cryptorchidism and in cases of testicular torsion. This results in the activation of mediator cells with an increasing synthesis of mediators of infection like TNF-α and the expression of cell adhesion molecules like ICAM (intercellular adhesion molecule) and VCAM (vascular cell adhesion molecule) at the cellular surface.

Methods

The expression of the cytokines IL-10 and TNF-α and the adhesion molecules ICAM and VCAM after defined testicular I/R injury in nine male transsexuals was evaluated with rt-PCR. Furthermore we examined lactate and the diameter of the testicular tubulus under ischemic conditions.

Results

During ischemia ICAM, IL-10, and VCAM do not show significant changes on the side of testicular ischemia and the contralateral side; the same was seen for the tubulus diameter. TNF-α and the testicular lactate values showed a significant change of the expression pattern.

Discussion

The statistical changes of TNF-α and testicular lactate are the expression of leukocyte migration, infectious reaction, and immune response. To what extent the TNF-α expression represents a severe immunological reaction remains undefined. This human study shows primary results for the immunological understanding of and cellular response to testicular ischemia.  相似文献   
109.
BACKGROUND: Differences in graft survival due to gender have been reported after transplantation of the kidney, liver, and heart. However, little is known about the role of donor and recipient gender in simultaneous pancreas-kidney transplantation. METHODS: Single-centre analysis was performed of first simultaneous pancreas-kidney transplantations performed between 1994 and 2005 at the Bochum Transplant Center in Germany (n=218). RESULTS: Recipients of female donor organs exhibited acute organ rejections earlier and more frequently (P<0.05). Male recipients of organs from male donors had a lower risk of acute rejection than recipients of female donor organs (P<0.05). In addition to female donor gender, higher donor age and early kidney dysfunction were risk factors for perioperative rejection (P<0.05). Long-term kidney and pancreas function was best in male-donor-to-female-recipient transplants over the time periods of 7 and 3 years, respectively (P<0.05). Risk factors of long-term organ failure were: the need of revision laparotomy, organ rejection, and early postoperative organ dysfunction (P<0.05). CONCLUSION: This is the first report of graft function after simultaneous pancreas-kidney transplantation looking specifically at gender differences with respect to donor and recipient. There was an increased risk of organ rejection of female donor organs.  相似文献   
110.
BACKGROUND: The risk of hemorrhagic complications after extracorporeal shock-wave lithotripsy (ESWL) increases in patients with aspirin intake, but the hematoma-inducing mechanism has not been understood completely at the ultrastructural level. METHODS: The effect off shock-waves on the kidneys of male Wistar-rats (n=24) was investigated in an experimental setting using a special ESWL device. Ultrastructural examination was performed by light-, transmission electron- and scanning electron microscopy. RESULTS: Shock-wave induced tissue damage appeared in all kidneys independently of aspirin intake. Endothelial detachment, lethal cell injury, gaps and mechanical disruption of the glomerular basement membrane were regularly found. After 1 week, repair processes were completed with evidence of permanent fibrosis in some cases. CONCLUSIONS: ESWL can induce modest as well as fatal damage to renal tissue cells. Therefore, after an ESWL-induced hematoma a second ESWL should not be performed within 1 week of the first treatment.  相似文献   
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