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81.
Contraction of urinary bladder by central norepinephrine originating in the locus coeruleus 总被引:3,自引:0,他引:3
Studies were performed to elucidate the role of the locus coeruleus, which is rich in norepinephrine-containing cell bodies, in vesical function using alpha-chloralose anesthetized cats. Stimulation of the locus coeruleus caused contraction of the urinary bladder, which was not affected by transection of the bilateral hypogastric nerves, but blocked by intravenous administration of hexamethonium, a ganglion blocking agent. In animals with transected hypogastric nerves, the locus coeruleus-induced contraction was inhibited by intrathecal administration of phentolamine (alpha-blocker) and prazosin (alpha 1-blocker), but not affected by intrathecal sotalol (beta-blocker) or yohimbine (alpha 2-blocker). In animals treated with reserpine, the locus coeruleus-induced contraction was enhanced by intravenous application of L-dopa, a precursor of norepinephrine. These results suggest that norepinephrine derived from the locus coeruleus activated preganglionic neurons in the sacral intermediolateral nuclei via alpha 1-receptors, thereby producing urinary bladder contraction. 相似文献
82.
In order to investigate how the ganglia in ganglionated plexus were distributed throughout the overall region of the gallbladder, the gallbladder was dissected from guinea-pig and washed with Krebs solution via the cystic duct. This gallbladder was distended with 2 ml of the mixed solution of OsO4 and ZnI2 injected with a syringe via the cystic duct and the cystic duct was immediately tied with a thread. The gallbladder was placed in excess of the mixed solution for 7-10 hours. The gallbladder was longitudinally divided into two approximately equal parts and each was prepared for microscopic investigation. The one preparation was the ventral side of the gallbladder and the other preparation was its dorsal side. These preparations were viewed through a photomicroscope. The obtained results were as follows: 1. Ganglia which involved several nerve cells were observed. Ganglia and nerve bundles connecting the fellow ganglia formed an irregular network, that is, the so-called ganglionated plexus. These nerve bundles were connected with the perivascular nerves which ran parallel to and around blood vessels in several places of the wall of the gallbladder. 2. Ganglia were full of variety in size and shape. That is to say, the shape of ganglia is arranged in various patterns such as oval, spherical, triangular, square and so on. When the size of ganglia were shown by surface area of ganglia which were viewed within the sweep of photomicroscope, the size of ganglia were divided into three large groups, the small ganglia in the range of 1,400 microns2-3,500 microns 2, the large ganglia in the range of 3,500 microns2-10,000 microns2 and the extra-large ganglia in the range of 10,000 microns2-38,000 microns2. Per one gallbladder, 240 +/- 41 (n = 3) small ganglia, 263 +/- 28 (n = 3) large ganglia and 8 +/- 1 (n = 3) extra-large ganglia were found. And these ganglia were irregularly scattered all over the wall of gallbladder. Small ganglia were found more numerous than large ganglia in the cervical portion of the gallbladder. On the other hand, small ones were slightly fewer than large ganglia in the remainder portion of the gallbladder. 3. The ganglionated plexus contained 511 +/- 69 (n = 3) ganglia.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
83.
Inhibition of HIV-1 infectivity with curdlan sulfate in vitro 总被引:5,自引:0,他引:5
Y Kaneko O Yoshida R Nakagawa T Yoshida M Date S Ogihara S Shioya Y Matsuzawa N Nagashima Y Irie 《Biochemical pharmacology》1990,39(4):793-797
Polymethoxylated flavones and C-glycosyl derivatives isolated from medicinal plants besides other flavonoid compounds were studied for their influence on lipid peroxidation induced by FeSO4+ cysteine in rat liver microsomes. A number of hydroxyflavones (e.g. luteolin); C-glycosyl-flavones (e.g. orientin); methoxyflavones (e.g. gardenin D) and flavonols (e.g. datiscetin), as well as the flavanol leucocyanidol and the biflavone amentoflavone behaved as inhibitors of non-enzymic lipid peroxidation. Structure-activity relationships were established and it was observed that the structural features for active polyhydroxylated compounds were different from those of polymethoxylated flavones, antiperoxidative flavonoids possessing a high lipophilicity. 相似文献
84.
85.
Y Kita Y Higashi M Kuze H Ito T Takeda H Takeuchi O Yoshida 《Hinyokika kiyo. Acta urologica Japonica》1992,38(3):277-280
Transurethral lithotripsy (TUL) was performed in the cases in which the ureteral calculi were not destroyed by the extracorporeal shock-wave lithotriptor (Dornier HM-3, EDAP LT 01). Preoperative placement of double-J ureteral catheter (D-J catheter) caused ureteral dilation, allowing smooth insertion of the ureteroscope. We divided the 55 TUL cases into two groups, those with (27) or without (28) a D-J catheter placed preoperatively, and compared requirement of ureteral bougination, difficulty of ureteroscope insertion and duration of operation between the two groups. In all cases with a D-J catheter, ureteral bougination was not necessary, the insertion of ureteroscope was easier and the duration of operation was shorter than the cases without a D-J catheter. Bladder irritable symptoms were seen in some cases with a D-J catheter but did not require removal of the D-J catheter. On the follow-up term after TUL, there was no difference in the incidence of postoperative fever or postoperative ureteral stenosis, between the cases with and those without a D-J catheter. 相似文献
86.
J Yoshida T Wakabayashi M Mizuno K Sugita H Seo M Oshima M Tadokoro S Sakuma 《Neurologia medico-chirurgica》1992,32(3):125-129
Iodine-131-labeled G-22 monoclonal antibody F(ab')2 fragment reaching specifically with a glioma-associated surface glycoprotein was administered to 12 glioma patients to investigate its use in radioimaging of intracranial gliomas. No immediate or delayed side effects were attributable to antibody injection. Nine patients received the radiolabeled complex intravenously. The images of low-grade gliomas were generally poor and disappeared within 4 days. High-contrast images were obtained beyond the 7th day in high-grade gliomas except one case in the pineal region. Three patients received intraventricular or intratumoral administration. Clear images of all tumors were demonstrated from the 2nd until later than the 7th day. One patient with cerebrospinal fluid (CSF) dissemination of brainstem glioma demonstrated negative CSF cytology after intraventricular administration. 相似文献
87.
Two variant cells lines resistant to the nitrosourea derivative ACNU ((1-4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride), namely C6/ACNU and 9L/ACNU, were selected in vivo from rat brain tumors. Stable resistance to ACNU proved to be a characteristic of these cell lines, whether they were grown in vivo or in vitro. These cell lines exhibited a different pattern of cross-resistance to a wide range of chemotherapeutic agents with dissimilar chemical structures and mechanisms of action as compared with that of other ACNU-resistant cell lines established in vitro. Distinct cross-resistance was observed in both the C6/ACNU and 9L/ACNU cell lines to chloroethyl-nitrosoureas such as BCNU (carmustine), CCNU (lomustine), and methyl CCNU and, additionally, to vincristine, vinblastine, Adriamycin (doxorubicin), and arabinosylcytosine, but not to bleomycin, methotrexate, cis-platinum, and 5-fluorouracil. This might point to a multifactorial mechanism of drug resistance in ACNU-resistant cell lines derived from rat C6 and 9L brain tumor cells. 相似文献
88.
I Hisatome N Sasaki M Yamakawa M Kobayashi Y Tanaka H Kosaka A Yoshida H Kotake H Mashiba A Takeda 《Nephron》1992,61(2):196-199
Two patients with diabetes mellitus had persistent hypouricemia due to increased urate clearance; the degree of the apparent renal hypouricemia with uricosuria was quite mild. At the onset of diabetes, their serum urate levels were normal. Even after good diabetes control in both cases, hypouricemia continued. Based on the pharmacological evaluation in both patients, pyrazinamide administration could partially decrease urate clearance, however, suppression by pyrazinamide was less than in normal subjects, and probenecid increased urate clearance. These results suggest that the present cases had a renal abnormality affecting tubular presecretory reabsorption of urate, which might be due to diabetes mellitus. 相似文献
89.
We successfully performed arterial embolization of an arteriovenous fistula between the left gastric artery and vein. The increased blood flow in the portal vein via the left gastric vein and the arteriovenous fistula induced severe portal hypertension. After obliteration of the left gastric artery, the arteriovenous fistula was not opacified on angiography and the portal hypertension improved. 相似文献