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61.
The presenting characteristics of 1423 consecutive admissions with proximal femoral fractures were prospectively studied, to determine any differences that may exist between patients, dependent on the radiological site of the fracture. Patients with intracapsular fractures were of a lower average age, more mobile, less likely to use walking aids or live in residential accommodation, they also had a considerably shorter length of hospital stay than for those patients with extracapsular fractures. Comparison against previous series shows that the average age of hip fracture patients and the proportion of trochanteric fractures is increasing.  相似文献   
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OBJECTIVE: To demonstrate that the dimension-weighted DSM-IV model for classifying the depressive disorders lacks utility. METHOD: The logical flaws in classifying the depressive disorders with any severity-based model (which underpin both the DSM-IV and ICD-10 systems) are noted. Integral definitional limitations to the DSM-IV definition of key depressive disorders are identified. It is argued that the DSM-IV classificatory system lacks utility for providing information on etiology and preferential management strategies. An alternative subtyping model is considered. RESULTS: It is asserted that, in practice, the DSM-IV model and criteria lack explanatory power and compromise research and clinical practice. CONCLUSIONS: It is hoped that this article evokes wider debate about modelling and classifying the depressive disorders.  相似文献   
65.
In human T cell lymphoma/leukemia virus (HTLV-1)-infected people with tropical spastic paraparesis (TSP), there are activated HTLV-1-specific cytotoxic T lymphocytes (CTL) in the circulation and lymphocytic infiltrates in spinal cord lesions that are rich in CD8+ T cells. These observations suggest a role for virus-specific CTL in the pathogenesis of TSP. We have examined the anti-HTLV-1 cytotoxic activity of freshly isolated CD8+ T cells from peripheral blood lymphocytes of eight subjects seropositive for HTLV-1. Four of five subjects with TSP had circulating activated anti-Tax CTL. However, two of three seropositive subjects without TSP also had activated anti-Tax CTL. These observations show that such activated CTL are not confined to patients with TSP and raise some uncertainty about their significance in the pathogenesis of the disease. In cultures of CD8+ T cells from two TSP subjects, we detected CTL with other HTLV-1 specificities, without exogenous antigenic stimulation. A CTL epitope in the middle region of Tax and one in the C terminus of Pol have been mapped at the peptide level and the HLA Class 1 molecules restricting their recognition have been defined.  相似文献   
66.
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
67.
Dye dilutional techniques are widely accepted for the assessment of intracardiac shunts, but current techniques require arterial access or radioisotope injection. Ultrafast (less than 500 msec) magnetic resonance (MR) imaging is ideally suited for the evaluation of an indicator during passage through the heart. Twenty patients were studied, including 13 with shunts. Four-chamber, T1-weighted images were obtained during bolus injection of gadopentetate dimeglumine. A single image was obtained in 420 msec, with repetitive images acquired after each QRS complex. After the contrast material was injected, there was pronounced signal intensity enhancement in the right atrium, followed by the right ventricular cavity, left atrium, left ventricular cavity, and descending aorta. Patients with substantial intracardiac shunts demonstrated early recirculation. First-pass contrast material-enhanced MR imaging is a promising new technique for the rapid assessment of intracardiac shunts. Combined with anatomic and functional MR imaging techniques, it can help provide a comprehensive noninvasive evaluation of suspected intracardiac shunts or provide follow-up in patients with known shunts.  相似文献   
68.
Several studies have suggested that 'anomalous parenting', as measured by the Parental Bonding Instrument (PBI), may be a differential risk factor to subsequent depression in adulthood--being irrelevant to melancholia but over-represented in non-melancholic depressive disorders. Such a 'specificity' effect is confirmed in our current sample of 65 melancholic and 84 non-melancholic depressed patients. Secondly, we examine the risk to depression effected by exposure to one parent with an anomalous parental style, and the extent to which that risk is modified by characteristics of the other parent. We find clear evidence of additive effects with the risk to non-melancholic depression being raised by exposure to 'anomalous parenting' from two parents. Of the varying parental styles measured by the PBI, low parental care from both parents provided the highest risk to non-melancholic depression (being 4-7 time higher in one sample and 13-27 times higher in the other).  相似文献   
69.
Fulminant necrotizing arteritis can be a rapidly fatal disease with protean manifestations often suggesting other diagnoses. We present two cases with angiographic and CT correlation and discuss CT findings that are suggestive of the diagnosis.  相似文献   
70.
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.  相似文献   
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