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101.
In this report, we provide evidence using a serial bone marrow transplantation (BMT) protocol that intra-bone marrow (IBM)-BMT (IBM-BMT) can efficiently reconstitute the hemopoietic system with cells of donor origin, in contrast to conventional intravenous (IV)-BMT (IV-BMT). Furthermore, the hematolymphoid system of secondary recipients that had received bone marrow cells (BMCs) from primary recipients treated with IBM-BMT recovered earlier than that of the secondary recipients of BMCs from primary recipients treated with IV-BMT. This was the case when the Lin-/c-kit+ progenitor cells of the secondary and tertiary recipients were examined. These findings indicate that IBM-BMT can facilitate the development of not only cells of various lineages but also the effective generation and, more importantly, the maintenance of the progenitor cells. Furthermore, we show that IBM-BMT can reconstitute the dendritic cell (DC) subsets (myeloid and lymphoid DCs), which are critical for the initiation of both adaptive and innate immune responses. The frequency of both myeloid and lymphoid DC subsets was approximately equal to that of normal age-matched untreated controls and, after second and third BMT, this ratio was close to that observed in the normal controls. However, the lymphoid DCs were clearly reduced in the secondary and tertiary recipients of BMCs from mice that had received IV-BMT. Therefore, the development of DC subsets is also normally maintained in the IBM-BMT group.  相似文献   
102.
This is the first study of micro-autoradiography (micro-ARG) for [18F]2-fluoro-2-deoxy- -glucose ([18F]FDG). The localization of [18F]FDG was demonstrated in dendrites of neuron and also in the myelinated axon in mouse normal brain in vivo. The nucleolus was relatively free of label. The counted silver grain numbers in autoradiogram were linearly correlated to the 18F radioactivities in the specimen. The micro-ARG using positron emitting 18F is a very time-saving technique with 4 hours exposure compared with the conventional method using 3H- or 14C-labeled tracers.  相似文献   
103.
Interferon regulatory factor-1 (IRF-1) is pivotal in the regulation of interferon (IFN)-mediated immune reactions, and studies suggest that IRF-1 is involved in the development of autoimmune diseases. IRF-1+/+, +/-, and -/- nonobese diabetic (NOD) mice were immunized with mouse thyroglobulin (mTg) to determine whether IRF-1 is required in experimental autoimmune thyroiditis (EAT), a murine model for Hashimoto's thyroiditis (HT). IRF-1-deficient mice developed EAT and anti-mTg antibodies comparable to IRF-1+/+ and +/- mice. Whereas both CD4+ and CD8+ T cells were found in thyroids of IRF-1+/+ mice, the latter was not in IRF-1-/- mice. Major histocompatibility complex class II antigen was comparably expressed in thyroids of IRF-1+/+ and -/- mice. Lack of IRF-1 resulted in decreased CD8+ T cell number in the spleen and reduced IFNgamma production by splenocytes. Our results suggest that IRF-1 is not pivotal in EAT in NOD mice.  相似文献   
104.
An improved method for constructing canine herpesvirus (CHV) recombinants expressing foreign genes by using the lacZ-TK gene cassette as a double selectional marker was developed. A recombinant CHV carrying the lacZ-TK gene at a targeted gene locus was constructed and used as a parental virus for generating new recombinants. The parental virus formed blue plaques and was sensitive to TK-specific drugs, while newly generated recombinants, in which the lacZ-TK gene was replaced with the desired foreign gene, become both resistant to the TK-specific drugs and formed white plaques. Recombinants were isolated by using the combination of drug selection and color selection. This improved method allows construction of recombinant CHV with great ease, because the drug selection can enrich the frequency of recombinant CHV from 0.01–0.1% to 10–80%. This method was employed to construct a recombinant CHV that expressed rabies virus (RV) glycoprotein (G protein). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
105.
Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983.  相似文献   
106.
We have reexamined the contradictory evidence in which task-dependent excitation of motor evoked potentials (MEPs) in the first dorsal interosseous (FDI) muscle was stronger with increasingly more complex finger tasks than with individual finger movement tasks. In the first step of the experiment, based on previous findings, we investigated remarkable functional differences between intrinsic and extrinsic hand muscles during complex finger tasks (precision and power grip). During the performance of the tasks, the optimal stimulus intensity of the transcranial magnetic stimulation (TMS) was applied to the contralateral motor cortex. MEPs of the FDI, extensor carpi radialis (ECR), and flexor carpi radialis (FCR) muscles were recorded simultaneously with increased background EMG activity step by step in both tasks. The intensity threshold of TMS was lower in the precision grip. Furthermore, the MEP amplitudes of FDI muscle dependent on the background EMG activity were different between these two tasks, i.e., MEP amplitudes and regression coefficients in a precision grip were larger than those in a power grip. Although our results for MEP amplitude and threshold in the FDI muscle were similar to previous reported evidence, the different contributions of a synergistic muscle (in particular, the ECR muscle) during performance in these tasks was new evidence. Since there were no differences in cutaneous afferent effects on both tasks, corticomotoneuronal (CM) cells connected to FDI motoneurons seemed generally to be more active during precision than power gripping, and there were different contributions from synergistic muscles during the performance of these tasks. In the second part of the experiment, the results obtained from the complex tasks were compared with those from a simple task (isolated index finger flexion). MEP amplitudes, dependent on the background EMG activity during isolated index finger flexion, varied among subjects, i.e., the relationship between the MEP amplitude and the background EMG of the FDI muscle showed individual, strategy-dependent modulation. There were several kinds of individual motor strategies for performing the isolated finger movement. The present results may explain the previous contradictory evidence related to the contribution of the CM system during coordinated finger movement.  相似文献   
107.
The polyhedrin gene inBombyx morinucleopolyhedrovirus (BmNPV) was replaced with the granulin gene ofTrichoplusia nigranulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infectedB. moriand BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin is insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability.  相似文献   
108.
109.
Journal of Artificial Organs - Few reports have examined the association between changes in cerebral oxygenation and clinical factors, including blood pressure (BP), upon standing after...  相似文献   
110.
The localization of Cu/Zn- and Mn-superoxide dismutase (SOD) in breast cancer tissue (12 papillotubular carcinomas, 21 solid-tubular carcinomas, 16 scirrhous carcinomas, 1 medullary carcinoma, 1 secreting carcinoma, 1 lobular carcinoma, 1 Paget's disease) was investigated via an immunohistochemical technique using antihuman Cu/Zn- and Mn-SOD antibodies in 10%formalin fixed-paraffin embedded thin sections. Both SODs stained strongly in the normal breast gland, but not clearly in many cancer tissues. Furthermore, Cu/Zn-SOD stained more strongly in well differentiated tubular carcinomas than in poorly differentiated tubular carcinomas. It tended to stain less in tumors which recurred or had a poor outcome, and in tumors with a diploid pattern on DNA flow cytometry. Mn-SOD staining was similar to that of Cu/Zn-SOD, but no significant differences among subgroups was found, since the incidence of positively staining tumors was too small in all groups. The intensity of SOD staining seems to change in relation to cell proliferation and differentiation in breast carcinoma, and may be a prognostic indicator, since SOD decreased in poorly differentiated carcinoma and in tumors which developed distant metastasis. Thus, the localization of SOD in breast cancer tissue can provide useful information for cancer treatment.  相似文献   
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