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71.
Acid hydrolases of the rat uterus in relation to pregnancy, post-partum involution and collagen breakdown 总被引:3,自引:1,他引:2 下载免费PDF全文
1. The rat uterus contains acid cathepsin, beta-glucuronidase, beta-galactosidase, acid phosphatase and deoxyribonuclease II at concentrations comparable with those found in liver. Two non-hydrolytic uterine enzymes, cytochrome c oxidase and aspartate aminotransferase, display only 2-6% of the activity found in liver. 2. The concentrations of acid cathepsin and beta-glucuronidase are significantly decreased in pregnancy and increase 3-4-fold during post-partum involution. 3. The concentrations of beta-galactosidase and acid phosphatase are not decreased in pregnancy and increase only 2-3-fold during involution. 4. The concentrations of these four acid hydrolases increase linearly during the first 4 days post partum and reach their peak values at the same time that wet weight and collagen content fall to their lowest point. 5. The concentration of deoxyribonuclease is depressed in pregnancy but does not rise above normal in the post-partum period. 6. Only a small proportion of each hydrolytic activity can be isolated in the mitochondrial-lysosomal fraction of sucrose homogenates of the rat uterus. This proportion increases during involution. However, the extensive mitochondrial rupture occurring during homogenization indicates that the technique is probably too harsh to obtain a true measure of the proportion of lysosomes present in the intact tissue. 7. There are no significant changes in either the concentration or subcellular distribution of the five acid hydrolases in the livers of the experimental rats during pregnancy or involution. In each case the largest proportion of the activity is found in the mitochondrial-lysosomal fraction of liver homogenates. 8. The results are interpreted in terms of the lysosomal theory of intracellular digestion. 相似文献
72.
Morphological comparisons are made from the study of 64 specimens belonging to the following species:Squalus acanihias, S. blainvillei, S. megalops andS. acutirostris. The results suggest conspecificity betweenS. acutipinnis andS. megalops. The differences betweenS. blainvillei andS. megalops in the E-Atlantic are stressed. The Indo-Pacific species calledS. blainvillei by Chen et al. (1979) is regarded in this paper as probably an undescribed species. Some consideration on the status of several nominal species and the species grouping withinSqualus are also made. 相似文献
73.
Erythrocyte-supplying function of the spleen was examined in the rainbow troutSalmo gairdneri under exercise. The spleen showed remarkable reduction, about 70% in weight and about 85% in hemoglobin content, after forced exercise of 15 min. The amount of erythrocytes released from the spleen was 2.33 ml/kg body, and this amount corresponds to about 20% of the total volume of circulating erythrocytes in resting condition. No damage was observed at the spleen, splenic artery and splenic vein after the exercise. Examination of the vascular system by a corrosion casting method showed that no place other than the venous circulation exists for the erythrocytes released from the contracted spleen. The spleen was strongly constricted by infusion of adrenaline into the organ. These facts imply that the fish spleen supplies stored hemoglobin into the circulating blood in response to an increased demand of oxygen during exercise, under the control of the sympathetic nervous system. 相似文献
74.
Tadao Niijima Takashi Umeda Manabu Kuriyama Hiroyuki Ohmori Yohsuke Matsumura Tomoyasu Tsushima Toyoko Tanahashi Jun Yoshimoto Toshihiko Asahi Norimasa Ike Taiichiro Johsen Noritaka Ishido Naoki Mitsuhata Takeshi Uyama Hiroyoshi Tanaka Hideo Ueda Jisaburo Sakatoku Norio Yamamoto Kazuo Nagata Yukitoshi Fujita Masaaki Morioka Kazuo Kurokawa Susumu Kagawa Tomoyuki Ishibe Yasutoshi Himeno Toyofumi Ueda 《Cancer immunology, immunotherapy : CII》1989,30(2):81-85
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects. 相似文献
75.
Ikuo Saiki Hiroaki Maeda Jun Murata Nobuchika Yamamoto Makoto Kiso Akira Hasegawa Ichiro Azuma 《Cancer immunology, immunotherapy : CII》1989,30(3):151-157
Summary We have investigated the effect of endogenous production of tumor necrosis factor (TNF) induced by the combination of recombinant interferon (rIFN) as a primer followed by GLA-60 as a trigger (rIFN/GLA-60) on murine lung metastases caused by B16-BL6 melanoma. In order to examine the therapeutic effect of endogenous TNF on tumor metastasis, the ability of multiple administrations of rIFN/GLA-60 to induce TNF production was also tested. The multiple administrations of rIFN/GLA-60 at intervals of 2 days were effective for the induction of endogenous TNF in mice but continuous multiple administrations of them for 2–4 days were not. In tumor-bearing mice, the production of endogenous TNF by rIFN/GLA-60 was less than that of normal mice, but treatment 3 days after the surgical excision of primary tumors showed the endogenous TNF production to be similar to that in normal mice. In the experimental lung metastasis model, intravenous administration of rIFN followed by intravenous or intranasal administration of GLA-60 showed potent inhibition of lung metastases of B16-BL6 melanoma, whereas the reverse sequence of administration (GLA-60/rIFN) or administration of a mixture of rIFN and GLA-60, which cannot induce the production of TNF, caused no inhibition of lung metastases. These results indicated that the regression of tumor metastases by rIFN/GLA-60 was mediated by the production of endogenous TNF in addition to the direct effects of both immunostimulants. Furthermore, the administration of rIFN and GLA-60 significantly inhibited the tumor metastases in spontaneous lung metastasis model. These results may provide a promising approach for the treatment of cancer metastasis as a result of its ability to induce endogenous TNF. 相似文献
76.
Francisco J. Campoy Maria Dolores Cánovas Encarnación Muñoz-Delgado Cecilio J. Vidal 《Neurochemical research》1989,14(2):197-204
Incubation of membranes derived from sarcotubular system of rabbit skeletal muscle with increasing concentrations of Triton X-100 produced both stimulation of the AChE activity and solubilization of this enzyme. Mild proteolytic treatment of microsomal membranes produced a several fold activation of the still membrane-bound acetylcholinesterase (AChE) activity. Attempts were made to solubilize AChE from microsomal membranes by proteolytic treatment. About 30–40% of the total enzyme activity could be solubilized by means of trypsin or papain. Short trypsin treatment of the microsomal membranes produced first an activation of the membrane-bound enzyme followed by solubilization. Incubation of muscle microsomes for a short time with papain yielded a significant portion of soluble enzyme. Membrane-bound enzyme activation was measured after a prolonged incubation period. These results are compared with those of solubilization obtained by treatment of membranes with progressive concentrations of Triton X-100. The occurrence of molecular forms in protease-solubilized AChE was investigated by means of centrifugation analysis and slab gel electrophoresis. Centrifugation on sucrose gradients revealed two main components of 4.4S and 10–11S in either trypsin or papain-solubilized AChE. These components behaved as hydrophilic species whereas the Triton solubilized AChE showed an amphipatic character. Application of slab gel electrophoresis showed the occurrence of forms with molecular weights of 350,000; 175,000; 165,000; 85,000 and 76,000. The stimulation of membrane-bound AChE by detergents or proteases would indicate that most of the enzyme molecules or their active sites are sequestered into the lipid bilayer through lipid-protein or protein-protein interactions and these are broken by proteolytic digestion of the muscle microsomes. 相似文献
77.
清香桂碱D和矮陀陀胺碱A,B的结构 总被引:9,自引:0,他引:9
本文报道从国产清香桂(Sarcococca ruscifolta)和金丝矮陀陀(Pachysandra axillaria)植物中分得的三个胺碱型新甾体生物碱清香桂碱 D 和矮陀陀胺碱 A、B 的化学结构,并首次归属了它们的~(13)C NMR 数据。 相似文献
78.
79.
R González-Cámpora G Mu?oz-Arias C Otal-Salaverri M Jorda-Heras E García-Alvarez A Gomez-Pascual A Garrido-Cintado A Hevia-Vázquez F Sánchez-Gallego H Galera-Davidson 《Acta cytologica》1992,36(6):905-917
We reviewed 98 cases of fine needle aspiration of soft tissue tumors with histologic confirmation performed during an eight-year period and propose a working morphologic classification based on the most prominent cytologic features. Six main tumor groups are recognized: myxoid, round cells, spindle cells, pleomorphic cells, polygonal cells and well differentiated. We believe that this classification allows recognition of the most common soft tissue tumors while helping with the differential diagnosis of other neoplasia, primary or secondary, with similar morphology and a similar presentation. 相似文献
80.
毛喉鞘蕊花的化学成分研究 总被引:17,自引:4,他引:13
本文报导了,从产于滇东北的毛喉鞘蕊花(Coleus forskohlii Brig)的根茎中分离到四个二萜化合物,经光谱分析鉴定,其结构分别为1α,6β,7α-triacetyl-coleonol—B(1),I-acetyl—forskolin(2),coleonol-B(3),和deacetyl-forskolin(4)。化合物(1)和(2)是首次从该植物中分离到。 相似文献