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171.
OBJECT: The treatment of complex cerebrovascular or skull base pathological conditions necessitates a microsurgical blood flow preservation or augmentative revascularization procedure as either an adjunctive safety measure or a definitive treatment. The brain is susceptible to ischemia, and procedure-related risks can be minimized by the reduction of occlusion time or the use of a nonocclusive technique. The authors therefore analyzed the feasibility of an automatic device (C-Port xA, Cardica) designed for constructing an end-to-side anastomosis with or without flow interruption for a middle cerebral artery (MCA) bypass in a human cadaveric model and in an in vivo craniotomy simulation model. METHODS: Four Thiel-fixated human head specimens were prepared using 8 standard pterional craniotomies. The sylvian fissure was opened to access the anterior circulation and in particular the MCA. The length of the individual vessel segments was measured. The C-Port xA was tested on each of the 8 exposures. In addition the C-Port xA was deployed in an in vivo craniotomy simulator model in 10 New Zealand rabbits (a total of 20 anastomoses) by using the abdominal aorta jump graft model. RESULTS: Short-term patency was assessed by angiography and histological findings. In all 8 sylvian exposures, construction of an MCA anastomosis with the aid of the C-Port xA was feasible. All 20 jump graft anastomoses performed in the in vivo craniotomy simulator were found to be patent. CONCLUSIONS: The anatomical studies as well as the in vivo craniotomy simulation studies demonstrated that the dimensions of the automated end-to-side anastomosis device are suitable for an extracranial-intracranial high-flow bypass on the MCA. Further miniaturization and special adaptation of this device would allow bypass procedures to more proximal intracranial vessels.  相似文献   
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173.
We describe a term infant without any features of congenital infection, who presented with respiratory distress at birth. Respiratory distress persisted despite change of antibiotics, and chest radiography showed bilateral diffuse patchy infiltrates. Congenital infections screening obtained on the 10th day of life was reported positive for syphilis. The infant was started on penicillin G and came off oxygen within five days. Although the presentation of congenital syphilis as pneumonitis in the absence of other clinical signs is unusual, in view of the re-emergence of the disease, syphilitic involvement of the lungs should be considered in any infant presenting with persistent diffuse lung disease of unknown etiology.  相似文献   
174.
A 58-year-old man with no history of cardiac diseases or cardiovascular risk factors was stung by honeybees. Soon after, he gradually developed signs of an allergic reaction followed by severe retrosternal pain. Electrocardiographic, echocardiographic evidence and positive biochemical markers were consistent with an acute anterolateral myocardial infarction. Coronary arteriography showed a left anterior descending artery thrombotic lesion. This is a case of Kounis syndrome, which is the concurrence of acute coronary syndromes with conditions associated with mast cell activation including allergic or hypersensitivity reactions as well as anaphylactic or anaphylactoid insults. The clinical implications and pathophysiology of this dangerous association are discussed.  相似文献   
175.
Elevated blood pressure is a major risk factor for cardiovascular morbidity and mortality. Increased risk begins in the prehypertensive range and increases further with higher pressures. The strenuous duties of emergency responders (firefighters, police officers, and emergency medical services (EMS) personnel) can interact with their personal risk profiles, including elevated blood pressure, to precipitate acute cardiovascular events. Approximately three-quarters of emergency responders have prehypertension or hypertension, a proportion which is expected to increase, based on the obesity epidemic. Elevated blood pressure is also inadequately controlled in these professionals and strongly linked to cardiovascular disease morbidity and mortality. Notably, the majority of incident cardiovascular disease events occur in responders who are initially prehypertensive or only mildly hypertensive and whose average premorbid blood pressures are in the range in which many physicians would hesitate to prescribe medications (140-146/88-92). Laws mandating public benefits for emergency responders with cardiovascular disease provide an additional rationale for aggressively controlling their blood pressure. This review provides a background on emergency responders, summarizes occupational risk factors for hypertension and the metabolic syndrome, their prevalence of elevated blood pressure, and evidence linking hypertension with adverse outcomes in these professions. Next, discrepancies between relatively outdated medical standards for emergency responders and current, evidence-based guidelines for blood pressure management in the general public are highlighted. Finally, a workplace-oriented approach for blood pressure control among emergency responders is proposed, based on the seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.  相似文献   
176.
Although primary effusion lymphoma (PEL) is usually associated with human herpes virus-8/Kaposi sarcoma herpes virus (HHV-8/KSHV) and human immunodeficiency virus (HIV), there are several reports of HHV-8/KSHV and HIV negative cases, mainly in the setting of immunodeficiency. Here, we report the second case of PEL associated with idiopathic T4 lymphocytopenia (ICL), which was HHV-8/KSHV negative, HIV negative and Epstein-Barr virus positive, while no other causative agents for immunodeficiency were documented. Flow cytometry revealed a hyperdiploid and highly mitotic large B-cell population, CD30, EMA, CD66, CD38 and CD71 positive. The malignant lymphoma cells showed atypia with prominent nuclei and basophilic vacuolated cytoplasm, while cytogenetic analysis with fluorescent in situ hybridization showed trisomy 18. The patient was administered R-COP chemotherapy, but no remission was achieved, up to 3 months from diagnosis.  相似文献   
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178.
Aims The frequency and the effect of alcohol and illicit drugs on injury type, severity and location of death in motor vehicle collision (MVC) fatalities were investigated. Design Retrospective case–control study based on autopsy and toxicology. Settings Single faculty accepting referrals from Greater Athens and prefectures. Participants Consecutive pre‐hospital and in hospital fatalities. Measurements Demographics, toxicology, abbreviated injury scale (AIS), injury severity score (ISS), and location of death. Findings Of the 1860 screened subjects, 612 (32.9%) constituted the positive toxicology group (PTG) for alcohol or illicit drugs or both and the 1248 (67.1%) the negative toxicology group (NTG). The median age was 34 (4–90) years for the PTG and 45 (3–97) years for the NTG. The PTG included significantly higher proportions of males and motorcyclists. The PTG had a 50% increased risk for a severe (AIS≥3) cervical spine and 85% for a severe upper extremity injury, compared to the NTG. A total of 29.2% of the PTG and 22.4% of the NTG deaths were non‐preventable (ISS = 75). The frequency of severe trauma (ISS≥16) was comparable between PTG and NTG (P = 0.87). The PTG presented with a median ISS of 43 (6–75) versus 41 (2–75) of the NTG, hence without significant difference (P = 0.11). The pre‐hospital death rate was 77.8% for the PTG versus 58% of the NTG (P < 0.001). The analysis confirmed that the odds of positive toxicology were considerably higher in the subjects who arrived dead at the hospital (OR 2.62, P < 0.001). Conclusions In the greater Athens region, almost a third of motor vehicle collision‐related fatalities involved alcohol, illicit drugs or both. Individuals screened positive for alcohol or drugs were 2.6 times more likely to die before hospital admission than those with a negative toxicology screen, despite comparable injury severity. Specific evidence‐based management protocols and reassessment of surveillance are required.  相似文献   
179.
We report a 71-year old man who presented with symptoms of adrenal insufficiency and large bilateral adrenal masses. Computed tomography guided FNA biopsy was not diagnostic. However, because of the rapid growth of the masses, the negative workup for primary malignancy and the strong clinical suspicion of a lymphoma, an open biopsy was performed and a B-cell lymphoma was disclosed.  相似文献   
180.
Heavy metal content of ayurvedic herbal medicine products   总被引:6,自引:0,他引:6  
Saper RB  Kales SN  Paquin J  Burns MJ  Eisenberg DM  Davis RB  Phillips RS 《JAMA》2004,292(23):2868-2873
Context  Lead, mercury, and arsenic intoxication have been associated with the use of Ayurvedic herbal medicine product (HMPs). Objectives  To determine the prevalence and concentration of heavy metals in Ayurvedic HMPs manufactured in South Asia and sold in Boston-area stores and to compare estimated daily metal ingestion with regulatory standards. Design and Setting  Systematic search strategy to identify all stores 20 miles or less from Boston City Hall that sold Ayurvedic HMPs from South Asia by searching online Yellow Pages using the categories markets, supermarkets, and convenience stores, and business names containing the word India, Indian cities, and Indian words. An online national directory of Indian grocery stores, a South Asian community business directory, and a newspaper were also searched. We visited each store and purchased all unique Ayurvedic HMPs between April 25 and October 24, 2003. Main Outcome Measures  Concentrations (µg/g) of lead, mercury, and arsenic in each HMP as measured by x-ray fluorescence spectroscopy. Estimates of daily metal ingestion for adults and children estimated using manufacturers’ dosage recommendations with comparisons to US Pharmacopeia and US Environmental Protection Agency regulatory standards. Results  A total of 14 (20%) of 70 HMPs (95% confidence interval, 11%-31%) contained heavy metals: lead (n = 13; median concentration, 40 µg/g; range, 5-37 000), mercury (n = 6; median concentration, 20 225 µg/g; range, 28-104 000), and/or arsenic (n = 6; median concentration, 430 µg/g; range, 37-8130). If taken as recommended by the manufacturers, each of these 14 could result in heavy metal intakes above published regulatory standards. Conclusions  One of 5 Ayurvedic HMPs produced in South Asia and available in Boston South Asian grocery stores contains potentially harmful levels of lead, mercury, and/or arsenic. Users of Ayurvedic medicine may be at risk for heavy metal toxicity, and testing of Ayurvedic HMPs for toxic heavy metals should be mandatory.   相似文献   
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