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81.
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   
82.
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   
83.
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   
84.
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   
85.
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   
86.
To determine the origin of dotlike epithelial membrane antigen (EMA) immunoreactivity of ependymoma, which is consistent with the eosinophilic globular body in hematoxylin and eosin (H&E) stain, an immuno-electron microscopic study was undertaken. The usefulness of antigen retrieval pretreatment in detecting the dotlike EMA immunoreactivity in ependymomas was also studied. The materials were 29 ependymomas, 7 autopsy brains as a normal control, and 50 brain tumors of various types. The study confirmed that most of the brown dots in EMA immunostain in ependymoma represented microlumina of tumor cells. In ependymomas, plain EMA immunostaining showed dotlike positivity in only six cases (21%), and antigen retrieval pretreatment increased the number of positives up to 26 cases (90%). Antigen retrieved CD99 detected 23 positive cases (80%) in ependymomas. On the basis of the results, although some false positive findings were raised by antigen retrieval pretreatment, the authors positively recommend adoption of the technique, especially when ependymoma remains as one of the differential diagnoses of the tumor.  相似文献   
87.
We compared preoperative evaluations of 93 fine-needle aspiration biopsies (FNAB) of major salivary gland tumors done over a 5 year period with pathologic diagnoses of surgically resected specimens. The overall accuracy was 88.5%. Eight of 15 aspirates from malignant tumors were correctly diagnosed by FNAB, for a sensitivity of 53.3%, while 69 of 72 aspirates from benign tumors were correctly diagnosed by FNAB, for a specificity of 95.8%. Five malignant tumors diagnosed as benign by FNAB were squamous cell carcinoma, carcinoma in pleiomorphic adenoma, malignant lymphoma, low-grade mucoepidermoid carcinoma, and acinic cell carcinoma. The false negatives in the first 2 cases appeared to be due to inaccurate placement of the aspiration site. The other 3 cases showed lack of atypia, leading to a benign diagnosis. Malignant lymphoma is difficult to diagnose as malignant, even in properly aspirated specimens, so we recommend open biopsy when malignant lymphoma is suspected from physical and radiological examinations. A case confirmed pathologically as benign myoepithelioma was diagnosed as adenoid cystic carcinoma preoperatively, based on the finding of a cribriform pattern containing mucin. It should be borne in mind that myoepithelioma and adenoid cystic carcinoma are difficult to distinguish by FNAB. Although FNAB is useful in diagnosing major salivary gland tumors, its low sensitivity (high percentage of false negatives) is undesirable. It may thus be helpful in intraoperative decision-making when combined with frozen sectioning.  相似文献   
88.
89.
Hoshi K  Ozawa H 《Clinical calcium》2003,13(4):415-419
Bone matrix consists mainly of hydroxyapatite and organics. The latter include various substances which interact with minerals. Osteoblasts secrete these organic substances and control crystal formation and growth of hydroxyapatite. The authors discuss the molecular mechanisms of calcification by focusing on the mineral/organic interaction.  相似文献   
90.
A 32-year-old man with a 1.7-cm tumor in the left kidney underwent laparoscopy-assisted partial nephrectomy. Although his postoperative course was uneventful, a 6-month postoperative CT scan showed hydronephrosis secondary to a severe stricture at the ureteropelvic junction. Heat injury to the urinary tract was strongly suspected. The use of microwave tissue coagulator for the tumor close to the renal sinus and excessive coagulation should be avoided to prevent heat-related complications.  相似文献   
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