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91.
The usefulness of HRCT in diffuse lung disease has already been established. However, it is not sufficient to evaluate the pathological changes of pulmonary parenchyma, often seen as ground-glass opacity(GGO). The author reviewed GGO, classified into four patterns, in light of each subject's pathological background, especially for interstitial pneumonia. Crazy-paving appearance was also reviewed. The imaging ability and usefulness of 0.5 mm HRCT were examined and compared with Multidetector CT. Finally, imaging with micro-CT and synchrotron radiation CT is discussed.  相似文献   
92.
93.
A 35-year-old man presented with a rare case of nevoid basal cell carcinoma syndrome, or Gorlin's syndrome, associated with both medulloblastoma and meningioma, manifesting as visual field constriction due to multiple parasellar tumors. He had undergone resection of a medulloblastoma at the age of 1 year 9 months, followed by adjunctive irradiation with a total dose of 40 Gy. He presented with multiple subcutaneous nodules on his face and neck. Histological examination of biopsy specimens established the diagnosis of nevoid basal cell carcinoma syndrome. Tuberculum sellae meningioma was removed through a craniotomy, and his symptoms improved. Meningioma is known to occur in the field of therapeutic irradiation, so chemotherapy may be a better option for medulloblastoma associated with nevoid basal cell carcinoma syndrome.  相似文献   
94.
Anterior fissure of the right liver--the third door of the liver   总被引:3,自引:0,他引:3  
Background/Purpose Although the anterior segment of the liver has been divided into segments 8 and 5, we have, during surgical or interventional procedures, occasionally encountered patients in whom the right anterior portal vein does not bifurcate into the superior and inferior branches. Thus, the in vivo anatomy of the right liver was reevaluated to clarify the segmental anatomy.Methods We evaluated the hepatic venous and portal ramification patterns, using three-dimensional images reconstructed from computed tomography. In addition, liver volumetry was performed.Results All branches arising from the anterior trunk were divided into two groups: the right ventral portal branches (RVP) and the right dorsal portal branches (RDP), and the anterior fissure vein crossed between the RVP and RDP. The ventral and dorsal regions of the anterior segment were approximately equal from a volumetric point of view.Conclusions The anterior segment seems to be divided into the ventral and dorsal segments by the anterior fissure, and we propose a reclassification of the right liver that divides the right liver into three segments. Dissection of the parenchyma along the anterior fissure makes the third door of the liver open, resulting in the exposing of all Glissonian pedicles of the right liver. The introduction of our segmental anatomy and surgical procedure will allow more systematic and limited liver resections.  相似文献   
95.
OBJECTIVE: The purpose of this study was to determine the safety and efficacy of nedaplatin and paclitaxel when given concurrently with radiation therapy (RT) for locally advanced non-small-cell lung cancer (NSCLC). METHODS: Nedaplatin was administered at a fixed dose of 20 mg/m(2), and paclitaxel was administered at a starting dose of 30 mg/m(2) with an incremental increase of 5 mg/m(2) until dose-limiting toxicity (DLT) occurred in more than one-third of the patients. The chemotherapy was administered once a week for 6 weeks. The RT was given at a single daily dose of 2 Gy for 5 days per week. The pharmacokinetics of nedaplatin and paclitaxel were investigated. RESULTS: Overall, 20 patients were recruited and assigned to three different treatment groups: group 1 (paclitaxel 30 mg/m(2)), group 2 (paclitaxel 35 mg/m(2)) and group 3 (paclitaxel 40 mg/m(2)). Pulmonary toxicity was the main toxicity which occurred in 16 of 20 patients. In group 3, grades 3 and 4 pulmonary toxicity occurred in two of six patients and grade 3 esophagitis in one patient. The maximum tolerated dose of paclitaxel in this study was 40 mg/m(2) and the recommended dose of paclitaxel was therefore 35 mg/m(2). Four complete and 11 partial responses were observed, resulting in a 75% overall response rate. The area under the concentration-time curve of paclitaxel in group 3 was significantly higher than that in group 1. CONCLUSION: Nedaplatin 20 mg/m(2) and paclitaxel 35 mg/m(2) could be safely administered for NSCLC with concurrent thoracic RT, and this regimen was effective. The most important DLT was pulmonary toxicity.  相似文献   
96.
Mismatches of minor histocompatibility antigens (mHas) between HLA-identical stem cell donors and recipients are known as a major risk factor for graft-versus-host disease (GVHD). We determined the alleles of 5 polymorphic molecules including HA-1 and 4 adhesion molecules in 102 patients who had undergone stem cell transplantation from HLA-identical donors and investigated the association of their mismatches with the relapse rate and incidence of GVHD. We observed relapse rates of 16.1% in patients with at least one or more incompatibilities and 39.4% in patients without incompatibilities (p = 0.018). The respective relapse rates of patients with CD62L, HA-1, CD31 exon 563, CD31 exon 125 and 49b incompatibilities were 6.1%, 14.3%, 11.7%, 20% and 40%. Only patients with CD62L incompatibilities showed a lower relapse rate than patients who received a compatible graft. Since there was no difference between patients with and without incompatibilities as far as the appearance of acute GVHD (> or = 2) was concerned, we conclude that the polymorphic CD62L molecule contributes to graft-versus-leukemia rather than the development of GVHD after HLA-identical stem cell transplantation.  相似文献   
97.
In the present study, we attempted to explore cell transplantation therapy for intracerebral hemorrhage (ICH) using embryonic stem (ES) cells. Collagenase-induced ICH rats were used as model animals. Mouse ES cells were differentiated into nestin-positive neural stem cells in vitro by alltrans retinoic acid (ATRA). ATRA-treated ES cells (10(5)) were transplanted into the lateral ventricle in the hemisphere contralateral to the hemorrhage 7 days after collagenase infusion. Twenty-eight days after transplantation, ES-derived neurons and astrocytes were observed around the hematoma cavities of the brain in all of the ten rats receiving grafts. Graft-derived neurons were found in the subependymal area of the lateral ventricle as cellular nodules. Although one of the ten rats receiving grafts showed uncontrolled growth of astroglia derived from the ES cells, intraventricular transplantation of ATRA-treated ES cells is an effective delivery system of neuronal lineage-committed progenitor cells toward the site of ICH.  相似文献   
98.
Transplantation of human neural stem cells (NSCs) is a promising potential therapy for neurologic dysfunctions after the hyperacute stage of stroke in humans, but large amounts of human NSCs must be expanded in long-term culture for such therapy. To determine their possible therapeutic potential for human stroke, human fetal neural stem/progenitor cells (NSPCs) (i.e., neurosphere-forming cells) were isolated originally from forebrain tissues of one human fetus, and expanded in long-term neurosphere culture (exceeding 24 weeks), then xenografted into the lesioned areas in the brains of Mongolian gerbils 4 days after focal ischemia. Sensorimotor and cognitive functions were evaluated during the 4 weeks after transplantation. The total infarction volume in the NSPC-grafted animals was significantly lower than that in controls. Approximately 8% of the grafted NSPCs survived, mainly in areas of selective neuronal death, and were costained with antibodies against neuronal nuclei antibody (NeuN), microtubule associated protein (MAP-2), glial fibrillary acidic protein (GFAP), and anti-2'3' cyclic nucleotide 3'-phosphodiesterase (CNPase). Synaptic structures between NSPCs-derived neurons and host neurons were observed. Furthermore, gradual improvement of neurologic functions was observed clearly in the NSPC-grafted animals, compared to that in controls. Human NSPCs, even from long-term culture, remarkably improved neurologic functions after focal ischemia in the Mongolian gerbil, and maintained their abilities to migrate around the infarction, differentiate into mature neurons, and form synapses with host neuronal circuits. These results indicate that in vitro-expanded human neurosphere cells are a potential source for transplantable material for treatment of stroke.  相似文献   
99.
The difference in tracer arrival times between the external radiation detector and the brain following administration of radioactivity (delay time) must be estimated correctly in order to quantitatively measure regional cerebral blood flow (rCBF) with positron emission tomography and [15O]H2O by autoradiographic method. Instead of intervenous injection of [15O]H2O, bolus inhalation of [15O]CO2 gas is sometimes used to simplify the measurement of rCBF. In the case of [15O]CO2, radioactive gas in mask and nasal cavity contributes large artifact on the sinogram data and it is difficult to estimate delay time from the sinogram data. In this paper, we proposed a new method to estimate the delay time using the sinogram data and the attenuation map (attenuation weighted sinogram method). In the present method, the attenuation map was used to eliminate the effect of the gas outside the brain region from the sinogram data. For the validation of the present method, PET data with [15O]CO2 (n = 10) were analyzed. Three methods, namely the image method, the sinogram method and the attenuation weighted sinogram method were used to estimate the delay time. The estimated delay times and calculated rCBF images by three methods were compared. Due to the radioactivity outside of the brain, the sinogram method significantly overestimated the delay time and thus underestimated the rCBF value compared with the image base method. On the other hand, there were good agreements between the delay times estimated by the attenuation weighted sinogram method and the image method. The present method can eliminate the effect of the radioactivity outside of the brain on the sinogram data and estimate the delay time accurately and fast enough for clinical use.  相似文献   
100.
We report a case of BCL-6-positive B cell lymphoma with human herpesvirus 8 (HHV-8) infection. A human immunodeficiency virus-infected patient developed a diffuse large B cell lymphoma, which was found exclusively in the liver and spleen with the absence of lymphadenopathy and effusion in any body cavities. The lymphoma cells were composed of medium to large-sized cells positive for CD20, CD45, and BCL-6, and negative for epithelial cell membrane antigen, CD30, CD45RO, and CD138/syndecan-1, suggesting a germinal center B cell origin. The patient was serologically positive for HHV-8, and HHV-8 was detected in the liver biopsy tissue both by polymerase chain reaction and by immunohistochemistry for HHV-8-encoded latency-associated nuclear antigen. Other HHV-8-associated diseases, such as Kaposi's sarcoma, primary effusion lymphoma, or multicentric Castleman's disease were not detected in the patient. Chemotherapy was effective and reduced the size of the lymphoma dramatically. This is the first case report of a germinal center B cell-originating lymphoma with HHV-8 infection.  相似文献   
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