16,434 research outputs found
Free-breathing 2D time-of-flight pulmonary MRA at 3T
This study aims to optimize and evaluate a free-breathing 2D TOF PMRA protocol at 3T. The protocol was based on a T1-weighted turbo field echo
sequence with static tissue suppression using magnetization transfer plus selective inverse recovery, spectral fat saturation, cardiac gating, respiratory
navigator gating, and parallel imaging. Satisfactory pulmonary MRAs were demonstrated in volunteer subjects (N=12). The proposed protocol is clinically
relevant for patients who are unable to provide long breath-holds during MRI scans.published_or_final_versio
Estrogen Binding Protein Activity in Morris Hepatoma 7777 Compared With Normal Rat Liver
Estrogen binding protein activities were determined in the cytosol from adult male Buffalo rat liver and Morris hepatoma 7777. Estrogen receptors were prepared using the protamine sulfate precipitation technique of Chamness. The ability of various unlabeled steroids competing with [3H]estradiol was examined to establish the binding specificity. Estradiol binding in Morris hepatoma 7777 cytosol was greatly decreased compared with that present in hepatic cytosol prepared from normal rat liver. The receptor concentration expressed as femtomoles per milligram of cytoplasmic protein was 31.1 ± 2.9 SD for normal rat liver and 0.41 ± 0.88 SD for the hepatoma. Gel filtration chromatography revealed the presence of an estrogen binder in hepatoma cytosol which was not present in either normal liver or in the protamine sulfate precipitates of hepatoma cytosol. The molecular weight, binding specificity, and precipitation of this protein by specific antiserum suggests that it is α-fetoprotein. © 1984, American Gastroenterological Association. All rights reserved
MOTSA TOF-MRA using multi-oblique-stacks acquisition (MOSA)
One of the intrinsic advantages of current TOF MRA techniques is their insensitivity to in-plane blood flow or turbulent flow, causing hypointense signal or
discontinuity in blood vessels in MRA images. To overcome this problem, a multi-oblique-stacks acquisition (MOSA) technique is proposed to improve the
visualization of in-plane blood flows in MRA. The results showed that TOF-MRA obtained from MOSA was improved as compared to that of conventional
MOTSA for the same amount of scan time.published_or_final_versio
The use of endoscopy in liver diseases
The use of fibre-optic endoscopy has greatly facilitated the management of some patients with chronic liver disease. Upper endoscopy plays a pivotal role in the diagnosis and management of oesophageal and gastric varices. With the use of reflectance septrophotometry, gastroduodenal mucosal haemoglobin concentration and oxygen saturation can be more precisely measured. Recently, it has been shown that acute gastroduodenitis is associated with a lower pre-treatment mucosal oxygen concentration in the antrum and the first part of the duodenum. Endoscopic ultrasound is increasingly being used to detect varices and in the staging of gastrointestinal tumours. Endoscopic retrograde cholangiopancreatography plays an important role in the diagnosis of recurrent pyogenic cholangitis and endoscopic sphincterotomy is a useful form of treatment. Laparoscopy, with the aid of ultrasound and biopsy is helpful in staging chronic liver disease, identifying focal lesions, and diagnosing peritoneal disease.published_or_final_versio
Efficacy of fine needle aspiration cytology in the diagnosis of tuberculous cervical lymphadenopathy
The results of a consecutive series of 1,349 fine needle aspiration (FNA) biopsies from the head and neck region of 1,193 patients has been reviewed in order to evaluate the efficacy of this method in the diagnosis of tuberculous lymphadenopathy (TBLN). Of the 108 patients whose fine needle aspiration cytology (FNAC) showed granulomatous changes, 68 had subsequent surgery and histological confirmation of the cytological appearance. Sixty-three had TBLN, thus the specificity of FNAC was 93 per cent in diagnosing tuberculous related granulomatous lymphadenopathy. One false positive FNAC was reported histologically to be metastatic mucoepidermal carcinoma. Of the 1,193 patients, 90 patients had subsequently TBLN confirmed histologically. Of these 90 patients, FNA from 69 showed granulomatous changes or acid fast bacilli (AFB), thus the sensitivity of FNAC in detecting tuberculous lymphadenopathy was 77 per cent. Fifty-two cytological smears were stained for acid fast bacilli. Nineteen (37 per cent) contained AFB. It is evident from this review that FNAC is an efficient way to detect cervical tuberculous lymphadenopathy.published_or_final_versio
MRI characterization of trabecular bone structure by exploring bone microscopic susceptibility effect
Bone strength depends on bone mineral density (BMD) as well as properties related to bone quality, such as the microarchitecture of trabecular bone.
Structural parameters, such as trabecular thickness, can also critically influence the mechanical competence and thus resistance to fracture of bone. Complex
bone structure can induce microscopic susceptibility effect and alter the bone transverse relaxation properties, which are expected to become more prominent
at high field. This study aims to examine such susceptibility effect at 3T and explore the possibility of using bone as an endogenous contrast agent to derive
the structural information in human trabecular bone.published_or_final_versio
Commercial property markets and property cycles in Chinese cities
This paper uses interview data to explore and examines property markets in three
Chinese cities with the focus placed on the emergence of the commercial property
markets and the government-market interplay, noting the market formation process
and cycles that are ‘unexpected’ in a transitional economy. The research identified
varying opinions and perceptions among key stake-holders about cycles in China’s
emerging commercial property markets. Interviews in the three cities suggested a
spectrum of factors that may substantially affect the stability of China’s office
markets. A cross-sectional comparison of the three cities has revealed a similar
pattern of cyclical behaviour highlighting structural change and state intervention with
leads-and-lags, in spite of the dispersion in geography, culture and market maturity.
The various views offered about market mechanism and cyclical behaviour represent
varying levels of market maturity. These brief insights offer an opportunity to develop
an alternative approach to measure property market conditions in emerging or
immature markets such as China.published_or_final_versio
Classes of Multiple Decision Functions Strongly Controlling FWER and FDR
This paper provides two general classes of multiple decision functions where
each member of the first class strongly controls the family-wise error rate
(FWER), while each member of the second class strongly controls the false
discovery rate (FDR). These classes offer the possibility that an optimal
multiple decision function with respect to a pre-specified criterion, such as
the missed discovery rate (MDR), could be found within these classes. Such
multiple decision functions can be utilized in multiple testing, specifically,
but not limited to, the analysis of high-dimensional microarray data sets.Comment: 19 page
New Generation of Tunable Bioactive Shape Memory Mats Integrated with Genetically Engineered Proteins
Aligned poly(l-lactide)/poly(methyl methacrylate) binary blend fibers and mats loaded with a chimeric green fluorescence protein having a bioactive peptide with hydroxyapatite binding and mineralization property are prepared by pressurized gyration. The effect of processing parameters on the product morphologies, and the shape memory properties of these samples are investigated. Integration of hydroxyapatite nanoparticles into the fiber assembly is self-directed using the hydroxyapatite-binding property of the peptide genetically engineered to green fluorescence protein. Fluorescence microscopy analysis corroborated with Fourier transform infrared spectroscopy (FTIR) data confirms the integration of the chimeric protein with the fibers. An enzyme based remineralization assay is conducted to study the effects of peptide-mediated mineralization within the fiber mats. Raman and FTIR spectral changes observed following the peptide-mediated mineralization provides an initial step toward a soft-hard material transition. These results show that programmable shape memory properties can be obtained by incorporating genetically engineered bioactive peptide domains into polymer fibers
- …