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421.
Pheochromocytomas are catecholamine producing neuroendocrine tumors that can be adrenal or extra-adrenal in origin. The classic symptoms of pheochromocytoma are headache, palpitation, anxiety and diaphoresis and the tumor can occur at any age with equal gender distribution. In patients with an established mutation or hereditary syndrome the condition may manifest at a younger age than in those with sporadic disease. Pheochromocytoma can be associated with certain genetic syndromes such as multiple endocrine neoplasia type 2 (MEN 2), neurofibromatosis (NF) and von Hippel–Lindau (VHL) syndrome. Pheochromocytoma is diagnosed with biochemical confirmation of hormonal excess followed by anatomical localization (CT or MRI). The mainstay of definitive therapy is surgical resection. In this review, we discuss in detail about the symptomatology, diagnosis, genetic aspects and management of pheochromocytoma.  相似文献   
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Chemokines direct leukocyte trafficking and positioning within tissues. They thus play critical roles in regulating immune responses and inflammation. The chemokine system is complex involving interactions between multiple chemokines and their receptors that operate in combinatorial cascades with adhesion molecules. The involvement of multiple chemokines and chemokine receptors in these processes brings flexibility and specificity to recruitment. The hepatic vascular bed is a unique low flow environment through which leukocyte are recruited to the liver during homeostatic immune surveillance and in response to infection or injury. The rate of leukocyte recruitment and the nature of cells recruited through the sinusoids in response to inflammatory signals will shape the severity of disease. At one end of the spectrum fulminant liver failure results from a rapid recruitment of leukocytes that leads to hepatocyte destruction and liver failure at the other diseases such as chronic hepatitis C infection may progress over many years from hepatitis to fibrosis and cirrhosis. Chronic hepatitis is charactezised by a T lymphocyte rich infiltrate and the nature and outcome of hepatitis will depend on the T cell subsets recruited, their activation and function within the liver. Different subsets of effector T cells have been described based on their secretion of cytokines and specific functions. These include Th1 and Th2 cells and more recently Th17 and Th9 cells which are associated with different types of immune response and which express distinct patterns of chemokine receptors that promote their recruitment under particular conditions. The effector function of these cells is balanced by the recruitment of regulatory T cells that are able to suppress antigen-specific effectors to allow resolution of immune responses and restoration of immune homeostasis. Understanding the signals that are responsible for recruiting different lymphocyte subsets to the liver will elucidate disease pathogenesis and open up new therapeutic approaches to modulate recruitment in favour of resolution rather than injury.  相似文献   
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Summary. Radioisotope synovectomy (RS) is defined as the intra‐articular injection of radioisotopic agents with the aim of fibrosis on hypertrophic synovium in the target joint. The aim of this study was to investigate genotoxic effects on lymphocytes and malign transformation induced by Yttrium90 (Y90) and Rhenium186 (Re186) in children with haemophilia undergone RS. Forty haemophilia patients were enrolled. The mean age was 16.4 ± 6.2 years (range: 8–40). Y90 was used for knees, Re186 was used for other joints. For safety, cytogenetic analysis was performed to determine potential chromosomal changes after RS procedure at three different time points as prior to procedure, 3rd day and 90th day. For the stimulation of chromosomal breakages, diepoxybutane was used (DEB test). Chromosomal breakages (CBs) were found in 23 patients (67.6%) prior to RS. We have found CBs additionally in nine of 11 patients who had no CBs prior to RS after 3 days of radioisotope exposure. At that time, the patients who had CBs were 29 (85.2%). At day 90, only 21 patients revealed (61.7%) CBs. The mean frequency of CBs slightly but not significantly increased in the 3rd day. However, there was a significant decreasing trend between 3rd and 90th days. Radioisotope synovectomy with Y90 and Re186 does not seem to induce the genotoxic effects significantly on peripheral blood lymphocytes. However, CBs even after one year in the re‐evaluation of four patients, significant decrease in the number of CBs between the 3rd and 90th days and de novo CBs after exposure may be accepted as warning signals for young population. It should also be pointed out that families and patients be informed properly related with historical and potential dangers of radioisotopic agents.  相似文献   
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Background/aim Epidural fibrosis (EF) is a common cause of failed back surgery syndrome seen after spinal surgeries. The most frequent reason for the formation of EF is accumulated blood and its products in the operation zone. On the development of EF, the effect of bipolar coagulation and fibrillar oxidized cellulose, which are used frequently to control bleeding, was investigated.Materials and methodsIn the study, 45 male Sprague Dawley rats were divided into three groups (control, fibrillar, and bipolar). Lumbar laminectomy was applied to all rats under sterile conditions. In the control group, the epidural area was washed with saline solution. Bleeding was controlled with fibrillar oxidized cellulose in the fibrillar group, with bipolar coagulation in the bipolar group. The area to which laminectomy had been applied was removed as a block 6 weeks later and evaluated histopathologically and genetically in terms of EF development. Fibrosis degree was determined histopathologically by counting fibroblasts using the modified Lubina and EF He grading systems. Interleukin-6 (IL-6), transforming growth factor beta-1 (TGFβ-1), and mRNA levels were measured by the droplet digital polymerase chain reaction method.ResultsThe number of epidural fibroblasts, percentage of modified Lubina, amount of IL-6, and He grading rates were significantly lower in the fibrillar group than in the bipolar and control groups (p ˂ 0.05). On the other hand, there was no significant difference among the control, fibrillar, and bipolar groups in terms of TGFβ-1 values (p= 0.525).ConclusionThe use of fibrillar oxidized cellulose was more effective for hemostasis than bipolar coagulation in reducing the development of EF.  相似文献   
426.
Alternative strategies to increase access to reproductive health services among internally displaced populations are urgently needed. In eastern Burma, continuing conflict and lack of functioning health systems render the emphasis on facility-based delivery with skilled attendants unfeasible. Along the Thailand-Burma border, local organisations have implemented an innovative pilot, the Mobile Obstetric Maternal Health Workers (MOM) Project, establishing a three-tiered collaborative network of community-based reproductive health workers. Health workers from local organisations received practical training in basic emergency obstetric care plus blood transfusion, antenatal care and family planning at a central facility. After returning to their target communities inside Burma, these first-tier maternal health workers trained a second tier of local health workers and a third tier of traditional birth attendants (TBAs) to provide a limited subset of these interventions, depending on their level of training. In this ongoing project, close communication between health workers and TBAs promotes acceptance and coverage of maternity services throughout the community. We describe the rationale, design and implementation of the project and a parallel monitoring plan for evaluation of the project. This innovative obstetric health care delivery strategy may serve as a model for the delivery of other essential health services in this population and for increasing access to care in other conflict settings.  相似文献   
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Tuberculostearic acid [(R)-10-methyloctadecanoic acid (TBSA)] is a structural component of mycobacteria, and its detection in appropriate clinical specimens has potential application as a rapid screening method for the presence of Mycobacterium tuberculosis and other mycobacteria. We used the highly sensitive technique of gas chromatography-mass spectrometry (GC-MS) combined with selected ion monitoring (SIM) of m/e 312 and m/e 167 for detecting TBSA in 405 clinical sputum specimens collected in Hong Kong, where tuberculosis is still common. TBSA was detected in 39 M. tuberculosis smear-positive, culture-positive specimens; 63 of 66 smear-negative, culture-positive specimens; and 1 of 300 smear-negative, culture-negative specimens. Thus, for screening of sputa from individuals with suspected pulmonary tuberculosis, the detection of TBSA by GC-MS/SIM is highly specific and more sensitive than conventional microscopy and more rapid but slightly less sensitive than conventional culture methods.  相似文献   
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