Radical polyaddition of bis(α‐trifluoromethyl‐β,β‐difluorovinyl) terephthalate [CF2?C(CF3)OCOC6H4COOC(CF3)?CF2] (BFP) with 1,4‐dioxane (DOX) was investigated under γ‐rays radiation from a 60Co source to produce higher molecular weight polymers compared to those yielded by benzoyl peroxide initiation. Prior to polyaddition, the addition reactions of 2‐benzoxypentafluoropropene [CF2?C(CF3)OCOC6H5] (BPFP) with tetrahydrofuran (THF) and DOX, and BFP with THF were examined in order to develop probable polyaddition reaction conditions. The polymer bearing 1.5 × 104 as a molecular weight was obtained under the feed molar ratio of DOX/BFP = 16 with an irradiation dose of 2 000 kGy at 40 °C, which is a much higher molecular weight compared to that yielded by benzoyl peroxide.
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease. 相似文献
Summary In pigmented rabbits anesthetized with N2O (70%) and halothane (2–4%), Purkinje cells were extracellularly recorded in the nodulus. Large field (60°×60°) optokinetic stimulation (OKS) with constant velocity was delivered to either the ipsi- or contralateral eye, and the direction and velocity selectivities of complex spike responses were examined. To ipsilateral OKS (n = 181), the preferred direction was forward (F, n = 72), upward (U, n = 38) or downward (D, n = 10), while the remaining cells (n = 61) showed no response (N). To contralateral OKS (n = 117), the preferred direction was backward (B, n = 22), upward (U, n = 7) or downward (D, n = 22), while the rest (n = 66) showed N. Cells tested with both eyes (n = 95) fell into 8 categories based on the preferred direction to ipsi- and contralateral OKS: (1) ipsi-F and contra-B (F/B type, n = 20), (2) ipsi-F but contra-N (F/N type, n = 12), (3) ipsi-U and contra-D (U/D type, n = 15), (4) ipsi-U but contra-N (U/N type, n = 13), (5) ipsi-N but contra-D (N/D type, n = 1), (6) ipsi-D but contra-N (D/N type, n = 5), (7) ipsi-N but contra-U (N/U type, n = 6), and (8) N to both eyes (N/N type, n = 23). The optimum velocity was in the range 0.1–2.0°/s for all cells responsive to OKS. In the ventral lamella, four medio-laterally aligned zones were demonstrated. In the most medial zone (0–0.5 mm from the midline), the majority of cells showed ipsi-N or contra-N responses. In the second zone (0.5–1.5 mm), most cells preferred ipsi-F or contra-B directions. In the third zone (1.5–2.5 mm), most cells preferred ipsi-U or contra-D directions. In the most lateral zone (2.5–3.5 mm), most cells preferred ipsi-F or contra-B directions. In the dorsal lamella, a longitudinal zone characterized with cells preferring ipsi-U or contra-D directions was found about 1.5–2.5 mm from the midline. This zone seemed to be the continuation of the third zone in the ventral lamella. Cells preferring ipsi-D or contra-U directions were scattered in the medial half of both the dorsal and ventral lamellae. Most cells responsive to electrical stimulation of the contralateral optic tract (OT) preferred the ipsi-F direction and were localized in the second and the most lateral zones of the ventral lamella. As for cells activated by a climbing fiber with a branching axon to the flocculus, no characteristic feature was found in terms of the preferred direction to OKS, except that none of the cells preferring ipsi-D or contra-U directions were activated by such branching climbing fibers. The results indicate that the nodulus consists of at least four functionally distinct zones in terms of direction selectivity of visual climbing fiber afferents. 相似文献
In pigmented rabbits anesthetized with N2O (70%) and halothane (2-4%), Purkinje cells were extracellularly recorded in the flocculus. A large central visual field (60 degrees x 60 degrees) was used to optokinetically stimulate either the ipsi- or contralateral eye, and the direction and velocity selectivities of complex spike responses were examined. For optokinetic stimulation (OKS) delivered to the ipsilateral eye (n = 129), the preferred direction was forward (F, n = 57) or upward (U, n = 37), while the remaining cells (n = 35) showed no response (N). For OKS delivered to the contralateral eye (n = 107), the preferred direction was backward (B, n = 11), downward (D, n = 42) or upward (U, n = 2), and the rest (n = 52) showed N. Cells tested with both eyes (n = 89) fell into five categories based on the preferred direction to ipsi- and contralateral OKS: (1) ipsi-F and contra-B (F/B type, n = 9), (2) ipsi-F but contra-N (F/N type, n = 28), (3) ipsi-U and contra-D (U/D type, n = 13), (4) ipsi-U but contra-N (U/N type, n = 17), and (5) ipsi-N but contra-D (N/D type, n = 22). The optimum velocity was within 0.1-2.0 degrees/s for all cells. On the average, the best response was obtained at 0.2-0.5 degrees/s stimulation. All ipsi-F cells responded to electrical stimulation of the optic tract (OT), while most cells preferring ipsi-U, contra-B and contra-D directions did not respond. No characteristic feature was found in cells innervated with collateralized climbing fiber branches to the nodulus. In the flocculus, cells preferring horizontal orientation (H cells, preferring ipsi-F and/or contra-B directions) were localized in a narrow dorsoventral zone (less than 1.0 mm) along the caudal border of the rostral one third, while those preferring the vertical orientation (V cells, preferring ipsi-U and/or contra-D directions) were in two distinct narrow zones located rostral and caudal to the H cell zone. H and V cells were intermingled in the central portion of the ventral flocculus. These four zones are in good agreement with previously defined H, anterior V, posterior V and R zones, respectively. The results indicate that the subdivision of the flocculus which controls horizontal (vertical) eye movements receives information regarding movements of the visual surround in the horizontal (vertical) orientation through visual climbing fiber afferents, thus being organized in olivo-cortico-nuclear functional units for control of eye movements. 相似文献
A rare variant of dedifferentiated chondrosarcoma wlth malignant mesenchymomatous component in a 57-year-old male is reported. The patient presented with a posterior mediastinal mass arising from the left eighth and ninth ribs showing well differentiated, low-grade chondrosarcoma. Five years later, local recurrence occurred and an excised specimen also showed the same histological features as the primary tumor. Another 6 years later, the tumor recurred and metastasized to the multiple organs, the patient dying 4 months later. Autopsy revealed that the recurrent and metastatic tumors showed malignant mesenchymomatous 'dedifferentiation' of chondrosarcoma composed of rhab domyosarcoma, angiosarcoma, chondrosarcoma, osteosarcoma, and leiomyosarcoma, in addition to fibrosarcomatous areas. Although the less differentiated component of dedifferentiated chondrosarcoma usually shows the histological features of malignant fibrous histiocytoma and fibrosarcoma, multilineage differentiation can occur in that component. The phenomenon of 'dedifferentiation' in chondrosarcoma and the relationship to and distinction from malignant mesenchymoma of soft tissue and bone are discussed. 相似文献
We compared the thin-section CT findings of 11 intrapulmonary lymph nodes with pathological findings and evaluated the possibility of CT scan differential diagnosis from pulmonary metastatic nodules. First, we retrospectively reviewed CT scan and pathological findings of intrapulmonary lymph nodes. The median size of these nodules was 6.2 mm. The nodules appeared round (n=3) or angular (n=8) in shape with a sharp border, and they were found below the level of the carina. The median distance from the nearest pleural surface was 4.6 mm, and 3 of the 11 nodules were attached to the pleura. On thin-section CT scan, linear densities extending from the intrapulmonary lymph nodes were frequently visualized, and were pathologically proven to be ectatic lymphoid channels. We then compared the thin-section CT findings of 8 metastatic nodules less than 1 cm in diameter with those of the 11 intrapulmonary lymph nodes. The median size of these nodules was 6.8 mm, and the median distance from the nearest pleural surface was 16 mm. All nodules appeared round in shape. None of the nodules had linear densities extending from the nodules. The linear densities on thin-section CT scan may be the most useful characteristic of intrapulmonary lymph nodes, when differential diagnosis from metastatic nodules is necessary. 相似文献
We evaluated effects of medium composition, including basic amino acid content and pH, on susceptibility to carbapenems such as imipenem, panipenem and meropenem, in clinical isolates of Pseudomonas aeruginosa. Susceptibility to carbapenems was reduced by basic amino acids in the medium, while susceptibilities to ceftazidime and aztreonam were not. Among carbapenems, susceptibility to panipenem was most sharply reduced by addition of basic amino acids to 1:16 Mueller-Hinton agar (MHA). In 174 of 175 clinical isolates, MICs for carbapenems were affected to different degrees by medium composition. One isolate, in which MICs for carbapenems did not differ between MHA and 1:16 MHA, showed reduced production of porin (OprD). Our results suggest that susceptibility to individual carbapenems, especially panipenem, is difficult to evaluate based on MICs for other carbapenems determined on MHA. For a better prediction of antibiotic efficacy, it may be important to evaluate the susceptibility for each carbapenem individually. 相似文献
Haematopoietic cells of the rat bone marrow were killed almost completely by using hydroxyurea (OHU), cytoslne arabinoslde (ara-C), 60Co irradiation and busulfan. The relation between the regeneration of haematopoietic cells of the bone marrow and the behavior of the bone marrow lymphocytes and related cells was investigated quantitatively. Bone marrow lymphocytes and related cells were cytologlcally classified Into lymphocytes, transitional cells and blastic cells on the smeared preparation. Comparing the results of the experiment using OHU 2.5 g/kg with those using whole body irradiation of 60Co 700R, the absolute number of nucleated cells In the bone marrow was reduced more prominently in the former case than in the latter. Nevertheless, regeneration of haematopoietic cells began earlier In the former case than in the latter. In the experiment using OHU 2.5 g/kg, haematopoietic cells in the bone marrow almost completely disappeared promptly after the treatment. On the contrary, the bone marrow lymphocytes were rather well preserved, making up 59% of control on the 1st day and 54% on the 2nd day. Moreover, it was evident that the decrease in number of bone marrow lymphocytes and the increase in number of transitional and blastic cells occurred simultaneously around the 4th day after the last dosage, just prior to the haematopoietic regeneration. On the 8th day after whole body irradiation with 60Co 700R, in parallel with the appearance of haematopoietic regeneration, the bone marrow lymphocytes, transitional cells and blastic cells were the predominant populations In the regenerating bone marrow. In the experiment using ara-G 600 mg/kg, the number of transitional cells increased evidently prior to haematopoietic regeneration. The author concluded that regeneration of bone marrow haemato-poiesis can take place earlier and more rapidly, when the bone marrow lymphocytes are provided In sufficient numbers. 相似文献