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91.
92.
Cysts morphologically identical to colloid cysts are rarely reported to be located in areas outside the third ventricle. We report the magnetic resonance (MR) imaging and spectroscopic findings in three patients with colloid like cyst located in the ponto-medullary, pre-pontine cistern and suprasellar region. The MR imaging and spectroscopy performed on a 1.5-tesla scanner in three female patients revealed T1 hyperintense mass lesions. A large dominant metabolite peak at 2.0-ppm chemical shift, simulating N-acetylaspartate (NAA) of normal neuronal tissue was detected within the lesion.This peak is probably due to the presence of glycoproteins secreted by the ciliated columnar epithelium lining these cysts. MR spectroscopy of colloid cyst has not been described in the literature and hence the findings in this study will help in the diagnosis of this cystic lesion especially when located at unusual location. The signal characteristics of these cysts in various sequences including diffusion weighted imaging (DWI) and susceptibility weighted imaging (SWI) are also discussed.  相似文献   
93.
Background Rasmussen encephalitis (RE) is a rare devastating disease of childhood causing progressive neurological deficits and intractable seizures, typically affecting one hemisphere. Characteristic MRI features include progressive unihemispheric focal cortical atrophy and grey- or white-matter high-signal changes and basal ganglion involvement, particularly of the caudate nucleus.Objective To analyse the pattern of involvement of different brain structures in a series of patients with RE and to attempt clinical correlation.Materials and methods We reviewed the medical records and neuroimaging data of 12 patients diagnosed with RE satisfying the European Consensus Statement diagnostic criteria.Results The disease manifested as seizures in all patients and was refractory; epilepsia partialis continua was a notable feature (nine patients). Hemiparesis of varying grades was noted in all but one patient; none had extrapyramidal signs. Neuroimaging showed cortical involvement in the insular/periinsular regions in 11 patients. Caudate atrophy was noted in ten patients. Putaminal atrophy was seen in nine patients, six of whom had additional hyperintense signal changes.Conclusions Our study highlights frequent putaminal atrophy and signal changes in RE, which suggests a more extensive basal ganglion involvement than emphasized previously. Recognition of putaminal changes may be a useful additional tool in the radiological diagnosis of RE.  相似文献   
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The purpose of the present study was to evaluate the biocompatibility and osteoconductive potential of pure and pigment forms of titanium dioxide. Pure and pigment forms of titanium dioxide were incorporated into prepared bur holes in the femur bone of rabbits. Implantation was done on six Albino rabbits which were sacrificed at the end of 3rd, 4th and 5th months after implantation. Radiographic, histologic and scanning electron microscopic evaluations of the implanted sites were performed. Heamatologic and soft tissue response to these materials were also evaluated. The results showed that both pure and pigment forms of titanium dioxide are biocompatible and have good osteoconductive properties. It was concluded that titanium dioxide can be effectively used in the augmentation of osseous defects and inadequate ridge forms.  相似文献   
96.
Since the first solid organ transplant between the Herrick twins in 1954, transplantation immunology has sought to move away from harmful immunosuppressive regimens towards tolerogenic strategies that promote long‐term graft survival. This has required a concerted multinational effort with scientists and clinicians working towards a common goal. Reports of immunosuppression‐free kidney and liver allograft recipients have provided the proof‐of‐principle, but intentional generation of tolerance in clinical transplantation is still only achieved infrequently. Recently, there have been an increasing number of encouraging developments in the field in both experimental and clinical studies. In this article, we review the latest advances in tolerance research and consider possible future barriers and solutions in achieving reliable graft acceptance in the long term.  相似文献   
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The purpose of this study was to assess the safety and long‐term efficacy of self‐expandable stents in the treatment of benign tracheal stenosis. Nine patients (seven men) with tracheal stenosis (including one with fistula) of varied cause were treated by fluoroscopically guided balloon dilatation and stenting with self‐expandable metallic stents. The procedure was carried out under topical spray in eight patients and under general anaesthesia in one patient. The patients were followed up for a period ranging between 13 and 60 months. In eight of the nine patients, satisfactory positioning of the stent was achieved at the first instance, with immediate relief of dyspnoea. One patient with innominate artery aneurysm died 16 days after the procedure because of renal failure. At 1 month of follow up, six out of eight (75%) of our live patients were without any respiratory embarrassment. This dyspnoea‐free result reached almost 90% by the end of 1 year especially so in the fibrous strictures. Four out of the eight live patients (50%) had cough for 2 months and two (25%) had mild blood‐tinged sputum treated by inhalation and mucolytic agents. Secondary intervention was required in one patient at 1 month because of recurrent symptoms. The patient with tracheo‐oesophageal fistula required surgical intervention because of fracture of the stent. Fluoroscopically guided balloon dilatation and stenting of the tracheal stenosis is an effective non‐surgical therapy resulting in cure of fibrous strictures and palliation in cases of malignancy.  相似文献   
99.
The gammaG-globulin eluted at acid pH from kidney cortex homogenates and isolated glomeruli of five of six patients with lupus nephritis was found to exhibit antinuclear activity, which was not dependent on presence of fresh human serum. Specificity, as demonstrated by absorption of antinuclear activity, was related to nucleoprotein in three glomerular acid eluates and to DNA in two acid eluates as well as in a deoxyribonuclease digest of disrupted glomeruli in one patient. Antinuclear activity was not found in acid eluates of kidneys from two patients with chronic liver disease and chronic discoid lupus, respectively, and one with lupus nephritis. These patients had a low titer of serum antinuclear factor and lesser amounts of kidney bound immunoglobulins. The presence of antinuclear activity in eluates of kidneys appeared to correlate with the amount of glomerular bound immunoglobulin and the level of antinuclear antibodies in serum. These findings suggest that in lupus nephritis, part of the glomerular bound immunoglobulin is derived from serum antinuclear factors possibly deposited as immune complexes.  相似文献   
100.
SETTING: Conventional methods for the identification of mycobacteria are slow and labour intensive. DNA amplification methods offer rapid sensitive and specific diagnosis. OBJECTIVE: To determine the feasibility of an in-house polymerase chain reaction (PCR) method to detect Mycobacterium tuberculosis in clinical samples. DESIGN: The present study focused mainly on diagnosing extra-pulmonary tuberculosis (EPTB) using an in-house PCR method in 465 clinical samples. This study also compared the efficacy of a standard phenol-chloroform (PC) extraction procedure and the guanidine thiocyanate with diatomaceous silica (GTCS) method of DNA extraction and purification. A subsample of patients was used for the validation of results based on the final diagnosis. RESULTS: Among 373 patients with suspected EPTB, 75 specimens were positive by PCR, four by microscopy and six by culture. Of the 25 PCR-positive patients, 95% had a final diagnosis of TB. Globally, the GTCS method was found to be superior to the PC method for DNA extraction and removal of inhibitors from clinical specimens. CONCLUSION: The DNA amplification method was found to be significantly more sensitive and rapid compared to culture and microscopy for a reliable final diagnosis of EPTB.  相似文献   
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