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1.

Background

Scintigraphy has been considered as competitive to MRI, but limited data are available on the accuracy of single photon emission tomography (SPECT) compared with MRI for the assessment of meniscal tears. Our objective was to assess the value of SPECT in comparison to MRI.

Methods

Between January 2003 and March 2004, sixteen patients were studied with both modalities and the accuracy rates of SPECT scan results, and MRI findings in the diagnosis of meniscal tears were compared. Arthroscopy was the gold standard.

Results

The respective sensitivity rate, specificity rate, and positive and negative predictive accuracies of MRI were 89%, 94%, 93%, and 79% and for SPECT those were 78%, 94%, 94%, and 88%. There was good agreement on the presence or absence of tears between two modalities (κ statistic = 0.699).

Conclusion

SPECT and MRI are both valuable imaging techniques. SPECT is a useful alternative when MRI is unavailable or unsuitable and it is beneficial when more possible accuracy is desired (such as when MRI results are either inconclusive or conflict with other clinical data).  相似文献   
2.
Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast entity scarcely reported in the medical literature. Its pathogenesis, etiology, and optimal treatment are still unknown. PASH tumors have a broad spectrum of clinical presentations and might be mistaken for malignancies. The authors present six patients diagnosed with PASH.  相似文献   
3.
BackgroundNeonates in low resource settings with a lack of pre-discharge screening and early intervention are at risk for complications associated with significant hyperbilirubinemia (SHB).ObjectivesTo determine the prevalence, factors associated and performance of transcutaneous bilirubin (TCB) in identifying well neonates with SHB.MethodsOver a one month period 235 well neonates 24 to 72 hours of age due for discharge at Kamempe-Mulago Hospital were enrolled in this study. Visual inspection using Kramer rule, transcutaneous bilirubin over the sternum using Draeger JM103 bilirubinometer, and serum bilirubin were determined. Neonates with SHB (total serum bilirubin warranting treatment) were referred for treatment. Relevant data were analyzed. A P-value of <0.05 was considered significant at 95% confidence interval.ResultsThirty two (13.6%) of the neonates had SHB and three (1.3%) had levels above exchange transfusion threshold. Significant hyperbilirubinemia was independently associated with CRP ≥ 10mg/l (AOR 3.96, CI 1.23–12.73, p 0.021), ABO discordance (AOR 3.67, CI 1.28–10.49, p 0.015), jaundice in a previous sibling (AOR 3.565, CI 1.10–11.51, p 0.034) and time of first feed > 1 hour (AOR 2.74, CI 1.10–6.90, p 0.007). The sensitivity, specificity, positive and negative predictive values of TCB were 96.5%, 84.6%, 47.5% and 99.4% respectively compared to 31.2%, 98.5%, 76.9% and 90% respectively for visual assessment (Kramer grading).ConclusionsA significant number of well neonates have SHB. Transcutaneous bilirubinometry is a suitable screening tool in this setting. Early initiation of feeding should be promoted. The cause for high CRP among well neonates with SHB needs to be studied further.  相似文献   
4.
European Archives of Oto-Rhino-Laryngology - Characterization of thyroid nodules is crucial to propose surgical intervention for histological verification. Cervical ultrasound potentially combined...  相似文献   
5.
Indoleamine 2,3-dioxygenase (IDO), an enzyme responsible for tryptophan catabolism, is thought to be required to prevent the rejection of the allogenic fetus by maternal T cells and to protect against intra- and extra-cellular pathogens. Consequently, we studied the expression of IDO in the endometrium of female Balb/c mice during the oestrous cycle. At each phase, the endometrium was peeled away and the relative expression of IDO mRNA was detected by semi-quantitative RT-PCR. The presence of IDO protein was confirmed in each phase by Western blotting and immunohistochemistry. Our results showed that IDO is expressed in the endometrium of cycling mice during all the phases of oestrous cycle. The expression of IDO was highest at the oestrus and lowest at the dioestrus. By means of Western blotting and immunohistochemistry, we obtained evidence that IDO protein is synthesised in the endometrium of cycling mice throughout the oestrous cycle. In accordance with RT-PCR results, IDO protein was predominant at the oestrus phase. IDO protein was mainly localised in the glandular and luminal epithelial cells. Our results support the concept of IDO providing a mechanism of innate immunity to protect from ascending infections of the female reproductive tract. In addition, considering the fact that mating only occurs during the oestrus phase, the high expression of IDO in this phase is likely to be a mechanism that induces immunological tolerance of the fetus.  相似文献   
6.
In this work, a WOx/CsyWO3 heterostructured composite was synthesized via a simple pyrolysis method followed by heat treatment under a reducing atmosphere. Optical absorption results revealed the WOx/CsyWO3 heterostructured composite exhibits a strong absorption tail in the Vis and NIR regions which could have important implications for its photoactivity. The photocatalytic performance of synthesized samples with different Cs/W molar ratios was evaluated by the photodegradation of RhB in aqueous solution under simulated solar light irradiation. The results revealed that the photocatalytic activity of the WOx/CsyWO3 composite is much higher than those of pure tungsten bronze (CsxWO3, x = 0.32, and 0.5) and pure WO2.83 samples, where 90% RhB was degraded after 160 min irradiation. Also, the WOx/CsyWO3 composite exhibits excellent photocatalytic activity for the degradation of MO, MB, RhB, and MG aqueous solution under visible light irradiation. It is proposed that the higher photocatalytic activity of the WOx/CsyWO3 composite could be attributed to the greater surface adsorption of dye molecules, intense light absorption in the visible and NIR regions, and photogenerated electron–hole separation.

In this work, a WOx/CsyWO3 heterostructured composite photocatalyst was synthesized via a simple pyrolysis method followed by heat treatment under a reducing atmosphere.  相似文献   
7.
Clinical Rheumatology - Biologics are indicated in rheumatoid arthritis (RA) in case of persistent high disease activity despite conventional disease-modifying anti-rheumatic drugs (cDMARDs) or...  相似文献   
8.
Monitoring recovery from diaphragm paralysis with ultrasound   总被引:1,自引:0,他引:1  
BACKGROUND: Diaphragmatic paralysis is an uncommon, yet underdiagnosed cause of dyspnea. Data regarding the time course and potential for recovery has come from a few small case series. The methods that have been traditionally employed to diagnose diaphragmatic weakness or paralysis are either invasive or limited in sensitivity and specificity. A new technique utilizing two-dimensional, B-mode ultrasound (US) measurements of diaphragm muscle thickening during inspiration (Deltatdi%) has been validated in the diagnosis of diaphragm paralysis (DP). The purpose of this study was to assess whether serial US evaluation might be utilized to monitor the potential recovery of diaphragm function. METHODS: Twenty-one consecutive patients with clinically suspected DP were referred to the pulmonary physiology laboratory. Sixteen patients were found to have DP by US (unilateral, 10 patients; bilateral, 6 patients). Subjects were followed up for up to 60 months. On initial and subsequent visits, Deltatdi% was measured by US. Additional measurements included upright and supine vital capacity (VC), maximal inspiratory pressure (Pimax), and maximal expiratory pressure. RESULTS: Eleven of 16 patients functionally recovered from DP. The mean (+/- SD) recovery time was 14.9 +/- 6.1 months. No diaphragm thickening was noted in those patients who did not recover. Positive correlations were found between improvement in Deltatdi% and interval changes in VC, Pimax, and end-expiratory measurements of diaphragm thickness. CONCLUSIONS: US may be used to assess for potential functional recovery from diaphragm weakness or DP. As in previous series, recovery occurs in a substantial number of individuals, but recovery time may be prolonged.  相似文献   
9.
Brain metastasis from papillary thyroid carcinoma (PTC) is extremely rare and carries a poor prognosis. We report nine cases (five females and four males) of brain metastasis of PTC. The age of patients ranged from 46 to 87 years old. The patients presented with nonspecific symptoms such as headaches. Brain metastasis was the first clinical presentation in three of nine patients; two of which had the aggressive tall cell variant of PTC. Six patients had prior history of PTC (four classic, one oncocytic variant, and one columnar cell variant) for 2 to 17 years with a median of 12 years. Gross total resection of brain metastasis was achieved for eight of our patients. Eight patients were treated with radioactive iodine. The median follow-up time was 12 months, ranging from 1 month to 4 years. Three patients died of their disease in 6 months, 21 months and 4 years, respectively after their first presentation of brain metastasis. It seems that these rare aggressive variants of PTC, such as tall cell variant, not only have higher propensity to develop brain metastasis, but also more frequently present with brain metastasis as their first clinical presentation than classic PTC. Furthermore, patients with PTC can develop brain metastasis even after many years.  相似文献   
10.
A synchronized dyshomeostasis of extra- and intracellular Ca(2+), expressed as plasma ionized hypocalcemia and excessive intracellular Ca(2+) accumulation, respectively, represents a common pathophysiologic scenario that accompanies several diverse disorders. These include low-renin and salt-sensitive hypertension, primary aldosteronism and hyperparathyroidism, congestive heart failure, acute and chronic hyperadrenergic stressor states, high dietary Na(+), and low dietary Ca(2+) with hypovitaminosis D. Homeostatic responses are invoked to restore normal extracellular [Ca(2+)](o), including increased plasma levels of parathyroid hormone and 1,25(OH)(2)D(3). However, in cardiomyocytes these calcitropic hormones concurrently promote cytosolic free [Ca(2+)](i) and mitochondrial [Ca(2+)](m) overloading. The latter sets into motion organellar-based oxidative stress, in which the rate of reactive oxygen species generation overwhelms their detoxification by endogenous antioxidant defenses, including those related to intrinsically coupled increments in intracellular Zn(2+). In turn, the opening potential of the mitochondrial permeability transition pore increases, allowing for osmotic swelling and ensuing organellar degeneration. Collectively, these pathophysiologic events represent the major components to a mitochondriocentric signal-transducer-effector pathway to cardiomyocyte necrosis. From necrotic cells, there follows a spillage of intracellular contents, including troponins, and a subsequent wound healing response with reparative fibrosis or scarring. Taken together, the loss of terminally differentiated cardiomyocytes from this postmitotic organ and the ensuing replacement fibrosis each contribute to the adverse structural remodeling of myocardium and progressive nature of heart failure. In conclusion, hormone-induced ionized hypocalcemia and intracellular Ca(2+) overloading comprise a pathophysiologic cascade common to diverse disorders and that initiates a mitochondriocentric pathway to nonischemic cardiomyocyte necrosis.  相似文献   
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