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31.
Heart tissues of patients with PD or incidental Lewy body (LB) disease (ILBD) were examined by light and electron microscopy. LBs and alpha-synuclein-positive neurites were identified in the hearts from 9 of 11 patients with PD and from 7 of 7 patients with ILBD. LBs were present in both tyrosine hydroxylase-positive and -negative nerve processes, which are nerves of extrinsic sympathetic and intrinsic origin, respectively. These findings provide histologic evidence that the postganglionic sympathetic and intrinsic neurons in the heart are involved in the PD disease process.  相似文献   
32.
We had surgically treated varicose veins in 554 legs of 386 patients as of June 30, 2000. Varicose veins of the stem or segment type without skin changes were treated with sclerotherapy combined with high ligation, while a part of secondary varicose veins and the reticular or web type were treated with sclerotherapy alone. This paper describes our methods for day surgery for this condition. The most important therapeutic consideration in the surgical procedure is achieving sufficient venous collapse to prevent the occurrence of intravenous thrombus. In our 386 patients, a massive intravenous thrombus that was resected occurred in one limb (0.1%). Postoperative bleeding also occurred in one limb (0.1%) of a patient with severe liver cirrhosis.  相似文献   
33.
We reported previously that an angiogenesis inhibitor, E7820, inhibits in vitro tube formation of human umbilical vein endothelial cell through the suppression of integrin alpha2 expression. Here we describe the antiangiogenic and antitumor effects of E7820 in mice and discuss the feasibility of using platelet integrin alpha2 expression on platelets as a biological marker of the efficacy of E7820. Oral administration of E7820 significantly inhibited basic fibroblast growth factor-induced angiogenesis in Matrigel implants and human colon WiDr tumor-induced angiogenesis in a dorsal air sac model. Twice-daily treatment with E7820 clearly inhibited the s.c. tumor growth of seven tumor cell lines derived from human colon, breast, pancreas, and kidney, and completely suppressed the growth of human pancreatic KP-1 and human colon LoVo cell lines. Moreover, E7820 significantly inhibited the growth of KP-1 and human colon tumor Colo320DM cells orthotopically implanted in the pancreas and cecum, respectively. The efficacy of E7820 was comparable in the s.c. and orthotopic transplantation models. Immunohistochemical analyses using anti-CD31 antibody showed that E7820 significantly reduced microvessel density in orthotopically implanted KP-1 tumor. E7820 reduced integrin alpha2 expression on a megakaryocytic cell line, Dami cells, induced by phorbol 12-myristate 13-acetate treatment. It also decreased the expression level of integrin alpha2 on platelets withdrawn from mice bearing s.c. KP-1 tumor at a dosage close to that affording antitumor activity. These data demonstrate that E7820 showed a broad-spectrum antitumor effect in mice through inhibition of angiogenesis and indicate that the decrease of integrin alpha2 on platelets might serve as a biological marker for the antitumor efficacy of E7820.  相似文献   
34.
35.
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
36.
The effects of conditioned fear on the release of noradrenaline in the hypothalamic paraventricular nucleus (PVN) and the involvement of corticotropin-releasing factor (CRF) receptor type 1 (CRFR1) in conditioned fear-induced changes in noradrenaline release were examined by intracerebral microdialysis in rats. Conditioned fear was produced by placing animals into a box where they had previously been exposed to a 5-min period of electric footshock, 135 min prior to the start of experiment. Conditioned fear for 20 min produced a significant increase in the release of noradrenaline in the PVN. Intraperitoneal preadministration of a selective nonpeptidic CRFR1 antagonist, CRA1000, completely blocked the conditioned fear-induced release of noradrenaline. These results suggest that CRFR1 is involved in the release of noradrenaline in the hypothalamic PVN induced by conditioned fear.  相似文献   
37.
Three different types of esophageal stents, the Z-stent, Ultraflex, and Wall-stent, exhibit different shapes on CT, which may suggest a difference in the radial forces applied by each of the stents. CT is useful for displaying the relationship between an esophageal stent and adjacent structures and complications.  相似文献   
38.
Diminution of contractile response of the aorta from endotoxin-injected rats   总被引:13,自引:0,他引:13  
The contractility of a helical strip of the thoracic aorta was studied in rats injected intraperitoneally with endotoxin. The contractile response to any of the agonistic agents, KCl, norepinephrine or 5-hydroxytryptamine was time dependently diminished in the endotoxin-injected rats compared to the controls. This diminution preceded the depression of blood pressure. When the external calcium concentration was increased from 2.5 to 7.5 mM after the KCl (80 mM)-induced contractile response reached a plateau, the diminished contractile response was reversed in the endotoxin-injected group. The strips from the endotoxin-injected rats showed a higher 45CaCl2 uptake into the vascular tissue with the KCl-stimulated contraction. These findings suggest that the blood pressure depression during endotoxic shock may be attributed partially to the diminished contractility of the blood vessels and that this diminution is induced by a disorder of calcium utilization within vascular smooth muscle during vascular contraction.  相似文献   
39.
A case of a parathyroid cyst associated with an adenoma in a different gland is reported. A 55-year-old female was explored with preoperative diagnosis of primary hyperparathyroidism after endoscopic removal of a right ureteral stone. The operation revealed a cyst, 20 x 10 mm in size at the left lower gland, and a solid tumor, 32 x 12 x 7 mm in size and 1,300 mg in weight in the left upper gland. Histological examination disclosed a parathyroid cyst and an oxyphilic and chief cell adenoma, respectively. Postoperative course was uneventful including normalized serum Ca level. To our knowledge, 59 cases of parathyroid cysts have been reported in the Japanese literature, of which 31 were in the hyperparathyroid status. The most common causes were cystic degeneration of the adenomas. A parathyroid cyst with a concomitant adenoma in a different gland like our case is very rare. This is the first reported case in Japan and the sixth reported case in the world literature.  相似文献   
40.
A synthetic DNA based on the known amino acid sequence of the brain/gut peptide cholecystokinin (CCK) was synthesized. This DNA contained deoxyinosines at ambiguous codon positions and was used as a probe to isolate the CCK gene directly from a human genomic library. Nucleotide sequence analysis of the isolated gene revealed that human preprocholecystokinin consists of 115 amino acid residues, with 11 amino acids in common with the human gastrin precursor, another member of the gastrin-CCK family, and that the coding region is separated by a single, long intron. CCK appears to be encoded by a single-copy gene in the haploid human genome, as revealed by genomic Southern hybridization analysis, suggesting that the same gene is expressed both in gut and brain.  相似文献   
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