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71.
The purpose of this study is to examine whether changing the way newspaper stories report crime and violence can induce shifts in readers' perceptions of the problem. Using an experiment that manipulates the framing and graphic presentation of newspaper stories on crime and violence, we seek to discover whether the public health model that calls for news stories to incorporate information on context, risk factors, and prevention strategies will help readers learn more about the context in which crime and violence occurs, endorse prevention strategies in addition to punishment, and become more attuned to societal risk factors and causes of crime and violence.  相似文献   
72.
73.
The purpose of this study was to investigate the effect of different application modes of high intensity focused ultrasound (HIFU) to muscle tissue. HIFU was applied to muscle tissue of the flank in C3H/Km mice. Two dose regimes were investigated, a continuous HIFU and a short-pulsed HIFU mode. Three hours after HIFU treatment pre- and post-contrast T1-weighted, T2-weighted images and a diffusion-weighted STEAM sequence were obtained. After MR imaging, the animals were euthenized and the treated, and the non-treated tissue was taken out for histology and functional genomic analysis. T2 images showed increased signal intensity and post-contrast T1 showed a decreased contrast uptake in the central parts throughout the tissue of both HIFU modes. A significantly higher diffusion coefficient was found in the muscle tissue treated with continuous wave focused ultrasound. Gene expression analysis revealed profound changes of 54 genes. For most of the analyzed genes higher expression was found after treatment with the short-pulse mode. The highest up-regulated genes encoded for the MHC class III (FC ≈84), HSP 70 (FC ≈75) and FBJ osteosarcoma related oncogene (FC ≈21). Immunohistology and the immunoblot analysis confirmed the presence of HSP70 protein in both applied HIFU modes. The use of HIFU treatment on muscle tissue results in dramatic changes in gene expression; however, the same genes are up-regulated after the application of continuous or pulsed HIFU, indicating that the tissue reaction is independent of the type of tissue damage. Hundt and Yuh contributed equally to this paper. Supported in part by the Lucas Foundation and the Phil Allen Truse.  相似文献   
74.

Background  

Lateral dislocation of the patella (LPD) leads to cartilaginous injuries, which have been reported to be associated with retropatellar complaints and the development of patellofemoral osteoarthritis. Therefore, the purpose of this study was to determine the reliability of MRI for cartilage diagnostics after a first and recurrent LPD.  相似文献   
75.
Glial cell line-derived neurotrophic factor (GDNF) promotes the survival or differentiation of several types of neurons. This study examines GDNF-induced signal transduction and biological effects in cultured striatal neurons. Results show that GDNF addition to striatal cultures transiently increased the protein levels of phosphorylated p42/p44, but did not change the levels of phosphorylated Akt. GDNF effects on phosphorylated p42/p44 levels were blocked by the mitogen-activated protein kinase (MAPK) pathway specific inhibitors (PD98059 and U0126). Activation of the p42/p44 MAPK pathway by GDNF led to an increase in the degree of dendritic arborization and axon length of both GABA- and calbindin-positive neurons but had no effect on their survival and maturation. These GDNF-mediated effects were suppressed in the presence of the inhibitor of the MAPK pathway (PD98059). Furthermore, the addition of the phosphatidylinositol 3-kinase pathway specific inhibitor (LY294002) blocked GDNF-mediated striatal cell differentiation suggesting that the basal activity of this pathway is needed for the effects of GDNF. Our results indicate that treatment of cultured striatal cells with GDNF specifically activates the p42/p44 MAPK pathway, leading to an increase in the arborization of GABA- and calbindin-positive neurons.  相似文献   
76.
Choi AK  Chow EC  Ho PC  Chow YY 《Hand Clinics》2011,27(3):369-382
Arthroscopic surgery has become the gold standard for the diagnosis and treatment of major joint disorders. With advancement in arthroscopic technique, arthroscopy has become feasible in most human joints, even those as small as the finger joints. The metacarpophalangeal joint (MCPJ) can become spacious with simple traction, the intra-articular anatomy is simple, and its major structures can be easily visualized and identified. However, MCPJ arthroscopy has never been popular. This article describes our experience with MCPJ arthroscopy and seeks to establish its role in clinical practice.  相似文献   
77.
Intrahepatic arterioportal shunt: helical CT findings   总被引:16,自引:0,他引:16  
The purpose of this study was to characterize the appearance of intrahepatic arterioportal shunts (APS) on two-phase helical CT, with emphasis on the importance of the hepatic arterial-dominant phase (HAP) to demonstrate perfusion disorders. We review eight cases of APS diagnosed by helical CT in our institution from January 1996 to March 1997 and describe the CT findings that established diagnosis. Five of them were confirmed by angiography. In seven (87.5 %) cases of APS we found early enhancement of the peripheral portal branches during the HAP of helical CT, whereas the superior mesenteric and splenic veins remained unenhanced. In five (62.5 %) cases of APS, transient, peripheral, triangular parenchymal enhancement was depicted during the HAP of helical CT; in four of these cases there was associated early enhancement of the portal branches. Helical CT can show perfusion alterations that might remain undiagnosed with conventional CT. An understanding of the hemodynamic changes that occur in APS can help in the interpretation of focal transient hepatic parenchymal enhancement and to differentiate APS from hypervascular tumors. We believe that the helical CT findings described herein are characteristic enough to suggest the diagnosis of APS. Received: 9 February 1998; Revision received: 25 May 1998; Accepted: 7 September 1998  相似文献   
78.
Postoperative pain is now a critical focus of perioperative patient care. The current perioperative analgesic strategy is a "balanced-multimodal analgesia". Cornerstones of this treatment approach are patient controlled neuraxial administration of local anesthetics and opioids or patient controlled intravenous administration of opioids. However, systemic opioids are limited by side effects. Thus, adjuvants like anticonvulsants, NMDA receptor antagonists, alpha-2 adrenergic agonists and other non-Opioid analgesics are considered to reduce pain and opioid requirements in the perioperative period. In the present review we discuss recent findings about the effectiveness of different systemic administered adjuvants including ketamine, lidocaine, gabapentin, pregabalin and corticosteroids for postoperative pain treatment. Furthermore a nurse based oral analgesic concept using controlled released Oxycodon for all postoperative patients without a patient controlled analgesia device will be introduced.  相似文献   
79.
We performed a systematic review of the literature on the diagnosis and treatment of secondary aortoenteric fistulas (AEF). A MEDLINE search was performed of articles published in English or Spanish between January 1991 and August 2006. Diagnostic methods, treatment modalities and the results of surgical treatment were analyzed. The most frequent first aortic surgery associated with AEF was repair of abdominal aortic aneurysm (54.31%). The most common form of presentation was gastrointestinal bleeding. Repair through in situ prosthetic replacement had the lowest early mortality rates (8-13.3%) compared with graft excision and extraanatomic revascularization (18.2-44%). AEF is a serious entity and diagnosis requires a high index of suspicion based on clinical findings and indirect data from imaging techniques (computed tomography). The most appropriate therapeutic option continues to be controversial.  相似文献   
80.
OBJECT: Surgery in the cerebellopontine angle (CPA) is a standard procedure at many centers. Outcome is focused mainly on preservation of hearing and facial function postoperatively. The nonmotor part of the facial nerve, the intermediate nerve, is nearly neglected nowadays. METHODS: A retrospective study was designed, including a questionnaire that was sent to 178 patients who had undergone surgery between 2000 and 2004. Data were obtained in 156 cases. The questionnaire was divided into five parts assessing the presence of increased tearing, reduced tearing, salivation disturbances, increased nasal secretions, and abnormalities in taste. Finally, a self-assessment of patient symptoms was analyzed. RESULTS: Postoperatively, 70 patients (45%) experienced crocodile tears, whereas 62 (40%) had dry eyes. Disturbances in taste were noted in six patients (4%) preoperatively and in 52 patients (33%) after surgery. Increased nasal secretion was noted in 68 patients (44%) postoperatively. An analysis of the correlation between the surgical approach used and disturbances in the intermediate nerve revealed a strong tendency to a higher rate of symptoms following the middle fossa approach (p = 0.071, chi-square test). CONCLUSIONS: Data in this study demonstrate the clinical importance of nonmotor defects associated with CPA tumor removal. More than 50% of the patients in this study reported postoperative crocodile tears, dry eyes, nasal secretions, and/or taste disturbances. These sequelae may affect both short- and long-term postoperative quality of life to the same extent as deafness or transient facial paresis. The risk of injury seems to be higher after the middle fossa approach.  相似文献   
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