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91.
One hundred twenty-five patients investigated at the Royal Brisbane Hospital, who underwent both hepatic ultrasonography and liver biopsy between 1980 and 1983, were scored quantitatively for ultrasound features of loss of detail, echogenicity, and attenuation, as well as for histologic features of fat, fibrosis, and inflammation. Strong correlations were found between the score for fat content and each of the three ultrasound features, and between the score for hepatic fibrosis and loss of detail and echogenicity, but there was no strong correlation with attenuation. Hepatic inflammation did not correlate with any of the ultrasound features. The correlations for fat were strongest when the interval between ultrasonography and liver biopsy was less than or equal to 7 days. Although ultrasonography had a positive predictive value of 98% in the diagnosis of diffuse parenchymal abnormality, it did not distinguish fat from fibrosis nor reliably diagnose cirrhosis. Ultrasonography gave false-positive results in only 2 patients, but in 17 patients, false-negative ultrasound examinations were encountered. These findings indicate that ultrasound is not a useful screening investigation for parenchymal liver disease, nor is it useful in gauging hepatic pathology. However, abnormal hepatic ultrasonography in patients with suspected liver disease strongly suggests the presence of diffuse liver disease.  相似文献   
92.
A continuous wave (CW) Doppler imaging system has been used in the assessment of patients with suspected carotid artery disease. In 137 comparisons with conventional angiography the sensitivity of CW Doppler Imaging was 91% and specificity 93% respectively in the detection of greater than 50% diameter internal carotid stenosis. The main diagnostic criterion for greater than 50% internal carotid stenosis was the presence of a peak internal carotid systolic Doppler shift frequency greater than 4 KHz. An examination protocol is recommended which combines CW Doppler imaging with common carotid waveform changes and the temporal artery compression test.  相似文献   
93.
Attitudes toward aging were assessed in three groups of elderly men (age 65-85), including: hospitalized veterans, veteran outpatients, and a group of non-hospitalized "healthy" veteran volunteers, using the Rosencranz and McNevin Semantic Differential Scale. Social objects rated included an "old man", a "young man", and the participant, himself, ("self"). Attitudes toward "old men" were significantly more negative than attitudes toward "young men" in all three groups. In addition, significant group by "object-rated" interactions were obtained on the autonomous/dependent and instrumental/ineffective dimensions of this scale. These interactions were attributable to a more negative "self" rating by the hospitalized group. These results suggest that within the population studied, older persons in poor health tend to view themselves more like the stereotyped "old person" than do healthy old people, who tend to perceive themselves as being more like a "young person".  相似文献   
94.
Twenty-five years have passed since the first randomised controlled trial began its recruitment for screening for abdominal aortic aneurysm (AAA) in men aged 65 and above. Since this and other randomised trials, all launched in the late 80s and 90s of the last century, the epidemiologic profile of abdominal aortic aneurysm may have changed. The trials reported an AAA prevalence in the range of 4-7% for men aged 65 years or more. AAA-related mortality was significantly improved by screening, and after 13 years, the largest trial showed a benefit for all-cause mortality. Screening also was shown to be cost-effective. Today, there are studies showing a substantial decrease of AAA prevalence to sometimes less than 2% in men aged ≥ 65 years and there is evidence that the incidence of ruptured aneurysm and mortality from AAA is also declining. This decline preceded the implementation of screening programmes but may be due to a change in risk factor management. The prevalence of smoking has decreased and there has been improvement in the control of hypertension and a rising use of statins for cardiovascular risk prevention. Additionally, there is a shift of the burden to the older age group of ≥ 75 years. Such radical changes may influence screening policy and it is worth reflecting on the optimum age of screening - it might be better to screen at ages >65 years - or rescreening 5 to 10 years after the first screen.  相似文献   
95.
Patel N  Teh BS  Powell S  Lu HH  Amato R  Butler EB 《Urology》2003,62(2):352
We report a rare case of metastatic prostate adenocarcinoma to the pituitary gland. The patient had lung and bone metastases when he presented with bitemporal hemianopsia. He was also receiving total androgen blockade at that time. Magnetic resonance imaging showed an intrasellar mass, and biopsy confirmed metastatic prostate cancer. Radiotherapy, in the form of intensity-modulated radiotherapy, was delivered to the intrasellar mass. The patient responded well to radiotherapy. The mechanisms of spread to the pituitary gland and treatment options, including intensity-modulated radiotherapy, are discussed.  相似文献   
96.
BACKGROUND: The accurate diagnosis of musculoskeletal tumours is important for successful treatment. Image guided biopsy is gaining increasing acceptance for obtaining tissue for diagnosis. The aim of the present study is to assess the accuracy of computed tomography (CT)-guided core needle biopsy of musculoskeletal tumours. METHODS: This is a retrospective study on a series of 127 patients with a musculoskeletal tumour. The biopsies were performed over a 4-year period from 1998 to 2001. The accuracy of the CT-guided core needle biopsy was determined by comparing the histology of the biopsy with the final histology of the specimen obtained at open biopsy or surgical resection of the tumour. The effective accuracy was determined by the accuracy of the biopsy to distinguish between a benign and malignant tumour. RESULTS: Computed tomography guided core needle biopsy in the present series has an overall accuracy of 80.3%. The effective accuracy as determined by a malignant versus benign lesion was 89%. There were 86 malignant tumours with a biopsy accuracy of 81.4% and there were 41 benign tumours with a biopsy accuracy of 78%. The positive predictive value (PPV) of a malignant tumour is 98.9% and the PPV of benign tumour 90.2%. The most common site of biopsy was from the femur and thigh, together accounting for 39.4% of the tumours. The most common tumours in this series were liposarcoma (n = 12), osteosarcoma (n = 11) and giant cell tumour (n = 11). There were no reported complications arising from the biopsy. CONCLUSION: Computed tomography guided core needle biopsy is a safe and effective procedure that is important in the diagnosis and management of musculoskeletal tumours. It should be performed in a specialized institution with a multidisciplinary musculoskeletal tumour team.  相似文献   
97.
Heparin-induced thrombocytopenia (HIT) is a potentially devastating immune mediated adverse drug reaction caused by the emergence of antibodies that activate platelets in the presence of heparin. Despite thrombocytopenia, bleeding is rare; rather, HIT is strongly associated with thromboembolic complications involving both the arterial and venous systems. A number of laboratory tests are available to confirm the diagnosis; however, when HIT is clinically suspected, treatment should not be withheld pending the result. Fortunately, therapeutic strategies have been refined, and new and effective therapeutic agents are available. Treatment options are focused on inhibiting thrombin formation or direct thrombin inhibition. Warfarin should not be used until the platelet count has recovered.  相似文献   
98.
Background It is unclear whether clinical features of pemphigoid gestationis (PG), such as timing of onset and severity, may affect pregnancy outcomes or whether the adverse outcomes in pregnancies complicated by PG are related to or worsened by systemic corticosteroid treatment. Objectives To evaluate the associations of adverse pregnancy outcomes with clinical features, autoantibody titre of PG, and systemic corticosteroid treatment. Methods We conducted a retrospective cohort study recruiting 61 pregnancies complicated by PG from the St John’s Institute of Dermatology database which enrolled cases from dermatologists across the U.K., and two tertiary hospitals in the U.K. and Taiwan. Outcome measures included gestational age at delivery, preterm birth, birthweight, low birthweight (LBW, i.e. birthweight < 2500 g), small‐for‐gestational‐age (i.e. birthweight below the 10th percentile for gestational age), fetal loss, congenital malformation, and mode of delivery. Results After controlling for maternal age and comorbidity, decreased gestational age at delivery was significantly associated with presence of blisters (P = 0·017) and disease onset in the second trimester (P = 0·001). Reduced birthweight was significantly associated with disease onset in the first and second trimesters (P = 0·030 and 0·018, respectively) as was also LBW [adjusted odds ratio (95% confidence interval) 13·71 (1·22–154·59) and 10·76 (1·05–110·65), respectively]. No significant associations of adverse pregnancy outcomes with autoantibody titre or systemic corticosteroid treatment were found. Conclusions Onset of PG in the first or second trimester and presence of blisters may lead to adverse pregnancy outcomes including decreased gestational age at delivery, preterm birth, and LBW children. Such pregnancies should be considered high risk and appropriate obstetric care should be provided. Systemic corticosteroid treatment, in contrast, does not substantially affect pregnancy outcomes, and its use for PG in pregnant women is justified.  相似文献   
99.
Obstructive sleep apnea, continuous positive airway pressure, and surgery   总被引:2,自引:0,他引:2  
Patients with obstructive sleep apnea (OSA) who have undergone upper airway surgery could be expected to improve if surgery alleviated some or all of the anatomic obstructions, or continue to desaturate at preoperative levels if the surgery was not corrective. Factors such as morbid obesity, general anesthesia recovery, and operative edema can potentially cause desaturations below preoperative levels. Because of this risk, patients with severe OSA have been considered for protective tracheostomy. The findings of our study suggest that selected patients who would have been past candidates for protective tracheostomy while undergoing surgery for severe OSA can, as an alternative, be considered for immediate postoperative use of nasal continuous positive airway pressure (CPAP). Ten surgical patients with severe OSA who elected surgical treatment were successfully treated with CPAP immediately after extubation and postoperatively to assist with airway patency and hemoglobin saturation. Postoperative followup included monitoring of continuous pulse oximetry, cardiac activity, and intermittent arterial blood gases. Preoperatively, all ten patients had marked decrease in oxygen desaturation levels during sleep, with a mean nadir oxygen saturation (SaO2) to 51.5%. After surgery, all patients in this group maintained SaO2 levels to no lower than 90%, with a mean SaO2 level of 93% while using CPAP on room air (F10(2) 21%) only.  相似文献   
100.
The membrane glucocorticoid receptor (mGR), previously correlated with glucocorticoid-induced lymphocytolytic competency, was purified under nondenaturing conditions from mGR-enriched mouse S-49 T lymphoma cells. Proteins were immunoaffinity batch adsorbed to BUGR-2 monoclonal antibody-coupled protein A Sepharose 4B beads, and elution by epitope competition was compared with standard denaturation procedures. Elution with BUGR-2 epitope peptides released multiple mGRs (42–150 kDa) and heat shock proteins 70 and 90, suggesting that mGR interacts with these protein chaperones under physiological conditions. The mGR-heat shock protein 90 interaction was inhibited by 1 μM geldanamycin. Several other mGR binding partners were captured and most were dissociated from mGR by 0.6M salt. Peptide maps of purified mGR displayed immunoreactive bands unique to mGR. Scatchard analysis estimated a kd value of 239 nM and a Bmax of 384 fmol/mg protein for mGR, compared to a kd of 19.5 nM and a Bmax of 90.3 fmol/mg protein for the intracellular GR (iGR). The rank order of affinities for mGR were RU-486 > dexamethasone > triamcinolone acetonide=aldosterone. Other steroids had no significant binding affinity. These results show that epitope-purified mGR on the plasma membrane of mouse lymphoma cells is similar but not identical to iGR.  相似文献   
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