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161.
The normal anatomy of the nasopharynx and floor of the middle cranial fossa was analyzed with magnetic resonance (MR) imaging. MR images from five healthy volunteers were correlated with whole-organ cryomicrotome sections from three cadavers. Anatomic connections exist between the paranasopharyngeal spaces and the surface structures of the skull base. These anatomic connections include the intimate relationship between the eustachian tube and the pharyngobasilar fascia, the attachment of the muscles of mastication and deglutition to the skull base, and vascular and nervous structures in the foramina. The inherent contrast between the soft tissues of the nasopharynx and related structures and the bone of the floor of the middle cranial fossa allowed excellent visualization of these anatomic connections.  相似文献   
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163.
The inflammatory process and autoimmunity in the form of antibodies to oxidized LDL are important factors in the formation of the atherosclerotic plaque. We examined the time relationship of oxidized lipoprotein antibodies to the acute oxidative stress of myocardial infarction (MI). We also examined the relationship of C-reactive protein, an index of inflammation, and therefore of free radical production, to oxidized low-density lipoprotein (LDL) antibodies. We examined five groups of patients in a cross-sectional study: group 1, within 48 h of MI; group 2, two days to 1 week; group 3, 1-4 weeks; group 4, 1-3 months; and group 5, 3-6 months post MI. Nine patients with high antibody levels were re-examined 12 months after their first assessment. Malondialdehyde (MDA)-LDL and MDA-HDL antibodies were determined by an ELISA method. The highest MDA-LDL antibodies were found within 48 h of MI, but there was no significant difference in MDA- HDL antibodies between the groups. When 9/10 patients with LDL antibodies greater than the mean of 2.7 were re-examined 1 year later, there was a significant decrease in the mean antibody levels (5.2 +/- 1.7 vs. 3.2 +/- 0.6, p < 0.02). There was no correlation between antibodies to MDA-LDL and antibodies to MDA-HDL. There was a positive correlation between serum HDL cholesterol and antibodies to MDA-LDL (r = 0.4, p < 0.02) and a positive correlation between serum triglycerides and MDA-HDL antibodies (r = 0.39, p < 0.02). Acute MI appears to be associated with significantly higher C-reactive protein and antibodies to MDA-LDL, suggesting a possible acceleration of the atherosclerotic process immediately prior to MI.   相似文献   
164.
Automatic implantable cardioverter defibrillators (AICDs) were studied in three groups: (a) Serial radiographs were reviewed in 51 clinic patients. Twenty of 96 (21%) AICD patches distorted with time. (b) Thirty-six postoperative computed tomographic (CT) scans of asymptomatic patients revealed that pericardial fluid collections were frequent during the month after surgery but rare beyond that. Echocardiography was insensitive for these collections. CT also demonstrated dense fibrosis around some distorted patches, months after surgery. (c) Five other patients with pericardial infection had distorted patches, and the four studied with CT had fluid beneath their patches. (d) A case of constrictive pericarditis had distorted patches but was not diagnosed with CT. The authors conclude that distorted patches may indicate postoperative complications and that CT is the imaging modality of choice.  相似文献   
165.
Interleukin 10 inhibits cytokine production of human AML cells   总被引:2,自引:0,他引:2  
BACKGROUND:: Unlike normal hematopoietic cells leukemic blasts from patientswith AML constitutively express cytokines like ILl, GM-CSF andTNF  相似文献   
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167.
Breast disease: dynamic spiral MR imaging   总被引:19,自引:0,他引:19  
  相似文献   
168.

Background

Several regimens for which efficacy was established in randomized controlled trials are recommended in current treatment guidelines for early breast cancer. However, knowledge on use and effectiveness of commonly administered chemotherapeutic agents in real-life care and across all breast cancer subtypes is limited.

Methods

The prospective, multicentre German TMK cohort study (Tumour Registry Breast Cancer) recruited patients in 148 oncology outpatient-centres. Data from 1650 patients who completed adjuvant chemotherapy were analysed regarding treatment regimens and taxane use from 2007 to 2014. The association of patient characteristics with application of taxane-free regimens was examined with a multivariate regression model.

Results

The preferred adjuvant treatment shifted from fluorouracil, anthracycline and cyclophosphamide containing regimens to anthracycline/taxane combinations. Taxane use increased for all subtypes, and the greatest rise was among node-negative patients. Older age, node-negativity, lower grading, HR-positive/HER2-negative subtype and earlier start year of therapy were significantly associated with taxane-free therapy.

Conclusions

Treatment with anthracycline/taxane-based chemotherapy in Germany has been rising for every subtype. The increased taxane use reflects updated guideline recommendations over the past decade. Cohort studies like the TMK provide insight into real-life treatment of patients outside of clinical trials.
  相似文献   
169.
In diagnostic radiology, the routine measurement of exposure levels for a reference patient is an important part of an effective quality assurance program. In the United States, chest radiography is the most frequent examination and has the lowest exposure level of all radiologic examinations. We estimated the amount of exposure an average patient received from both manual and automatic exposure-controlled radiographic techniques by using a "patient-equivalent" chest phantom during measurements. A densitometric procedure was used to assess processor performance. The mean exposure from 194 chest systems was 20 mR (5.16 X 10(-5) C/kg); the mean film density, 1.38; and the mean processing speed, 108. It is interesting to note that a wide range of radiographic techniques, processing conditions, and screen-film speeds are currently being used. With the information given in our study, investigators can begin to identify the problems that lead to unusual exposure levels and, perhaps, poor image quality.  相似文献   
170.
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