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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
931.
We examined intrarenal localization of receptors for alpha-rat atrial natriuretic polypeptide (alpha-rANP) by injecting [125I]-labeled ligand in vivo into the rat aorta. We found that the receptors for alpha-rANP are distributed also on the vasa recta of the outer and inner medulla in addition to the previously reported sites, i.e., the renal arteries, renal pelvis, glomeruli, and inner medullary tissues including collecting tubules. In the vascular bundle of the outer medulla, the majority of grains was preferentially localized on the arterial vasa recta. The electron microscopic autoradiography of the glomerulus showed that the binding sites were mainly localized on the foot process of the podocyte. Since alpha-rANP injected into the aorta under physiological conditions was bound to the glomerulus and vasa recta in the kidney, the effect of ANP on these binding sites may be important in the mechanism of natriuresis. 相似文献
932.
Effects of vancomycin and ofloxacin on rabbit ERG in vivo 总被引:1,自引:0,他引:1
The retinal toxicity of vancomycin and ofloxacin was studied by electroretinogram (ERG) before and after intravitreal injection in rabbits. Vancomycin is known to be effective on methicillin-resistant Staphylococcus aureus. A dose of 1mg vancomycin caused no ERG change for at least eight weeks after injection. The feature that ERG became non-recordable during one to four weeks after an intravitreal injection of 10mg vancomycin, with recovery of only the c-wave was conspicuous. A dose of 200 micrograms ofloxacin did not cause deterioration of the b-wave, the c-wave or the oscillatory potentials throughout the follow-up period up to eight weeks. Judging from the susceptibility of each ERG component to antimicrobials and taking into account the difference of vitreous volume between rabbits and humans, clinical doses of intravitreal single-shot injection should be less than 1mg for vancomycin and 200 micrograms for ofloxacin. 相似文献
933.
Sun Ren-yu孙仁宇 Yan Yi-zhao严仪昭 Zhang Hong张宏and Li Chang-cheng李长城Institute cf Basic Metiical Sciences Chinee Academy of Medical Sciences Beijing 《中华医学杂志(英文版)》1989,102(1):1-6
Acute pulmonary hypertension was caused by
inhalation of 5% 02 in rats. Pulmonary vascujar re-
sistance (PVR) increased, but heart rate (HR), cardiac
output (CO) and carotid arterial pressure (CAP) were
not obviously changed. After an intravenous admini-
stration of Radix Angelicae sinensis, the acute
pulmonary hypertension induced by inhalation of 5%
O2 could be attenuated, but this effect disappeared if
propranolol was given before Radix Angelicae sinensis.
In chronic experiments, the same results were
obtained, but the protective effect of Radix Angelicae
sinensis on heart function was not influenced by
propranolol. It is suggested that Radix Angelicae
sinensis rmght play a role by stimulating the
βz-receptor in the prevention of acute and chronic
hypoxic pulmonary hypertension. However, prevention
of hypertrophy of the right ventricle and enhancement
of heart function in chronic hypoxic rats might not be
attributed to the β1 receptor in the heart. 相似文献
934.
935.
V. Pellegrini S. Ohno S. Hirose H. Matsuda Y. Hiraga 《The British journal of ophthalmology》1986,70(6):474-477
A 49-year-old Japanese man presented with chronic granulomatous uveitis in his left eye. Later he developed macular subretinal neovascularisation. The chest x-ray showed bilateral hilar lymphadenopathy. Bronchoscopy and gallium-67 scanning were positive, PPD skin test negative, and serum angiotensin converting enzyme (ACE) levels increased. Ophthalmoscopy and fluorescein angiography of the left eye showed perivasculitis, retinochoroidal exudates, snow banking, and vitreous opacity. On these findings, the diagnosis of sarcoidosis was made. Treatment was based on topical corticosteroids, mydriatics, beta blockers, and oral carbonic anhydrase inhibitors. After 15 months the visual acuity decreased in the left eye, and a neovascular membrane was observed in the macula. Fluorescein angiography confirmed subretinal neovascularisation. Almost two years later the patient still has the neovascular membrane in his left eye. 相似文献
936.
M A Gabal Y L Awad M B Morcos A M Barakat G Malik 《Veterinary and human toxicology》1986,28(3):207-212
Mycotoxicoses involving horses, rabbits and cattle have been studied. Fusarium tricinctum and T-2 toxin were isolated from all incriminated feedstuffs. Other isolated trichothecenes from the feed included HT-2, verrucarins and roridin. The toxins were separated, identified and quantitated using thin-layer chromatography, gas-liquid chromatography and mass spectrometry. T-2 toxin was detected in amounts varying from 0.5-204 ppm. The contaminated feedstuffs in connection with the affected horses and rabbits, included cereal grains (corn, cornstalks, bran and barley), whereas fescue hay was associated with the mucocutaneous findings in the bovine episode. The effects of the toxin(s) seemed to be host specific and varied according to the different animal species. Horses and rabbits developed primarily central nervous disorders with conspicuous pathological findings in the brain. Hepatitis and nephritis were also seen in naturally intoxicated horses and experimentally fed rats. Affected cattle developed mucocutaneous eruptions around the mouth and nostrils. In addition, dermonecrotic findings were observed involving the extremities, ear and tail. Fusariotoxicoses are toxic conditions of farm animals and man caused by the ingestion of cereal grains and forages contaminated by different fungal species of the genus Fusarium. A variety of clinical and pathological findings have been reported (5,6,10,13,15,17,31). This study concerns neuropathic findings in horses and rabbits and mucocutaneous lesions in cattle in association with T-2 toxin contamination. 相似文献
937.
938.
Application of a radiotelemetric system to evaluate the performance of enteric coated and plain aspirin tablets 总被引:1,自引:0,他引:1
The bioavailability of enteric coated and plain aspirin tablets was studied in four beagle dogs. Blood sampling for enteric coated tablets was planned with the aid of a radiotelemetric system. The release of aspirin from its dosage form was detected by monitoring the change in intestinal pH. Aspirin and salicylic acid levels in plasma obtained from the enteric coated dosage form exhibited familiar concentration versus time absorption profiles. Variation in the plasma concentrations of these two compounds within each dog studied (four runs each) was relatively small when time zero was adjusted to the commencement of tablet dissolution. The plasma levels obtained from plain aspirin (three runs each), however, show atypical absorption. The estimated absolute bioavailability was 0.432 +/- 0.0213 and 0.527 +/- 0.0260 for enteric coated and plain aspirin, respectively. Other pharmacokinetic parameters for these two dosage forms such as the highest observed plasma concentration (Cmax) (10.9 +/- 0.535 microgram/mL versus 13.6 +/- 1.88 micrograms/mL) and the time to reach Cmax (tmax) (26.6 +/- 1.94 min versus 31.0 +/- 7.04 min) agree well. The mean values for gastric emptying time, in vivo coating dissolution time, and in vivo disintegration/dissolution time of the tablet core for enteric coated aspirin are 48.7 +/- 7.23 min, 44.3 +/- 3.80 min, and 34.7 +/- 2.04 min, respectively. 相似文献
939.
T Tsuda M Uchiyama T Sato H Yoshino Y Tsuchiya S Ishikawa M Ohmae S Watanabe Y Miyake 《Journal of pharmaceutical sciences》1989,78(2):91-94
The byproducts P-1 and P-2, which were produced during the synthesis of porcine secretin, were isolated in pure form from the crude secretin by HPLC. These were identified by a combination of amino acid analysis, enzymatic digestion, and isocratic or linear gradient reversed-phase (RP)-HPLC. The amino acid compositions of P1 and P2, determined by amino acid analysis after acid hydrolysis, were found to be the same as those of porcine secretin without distinction between L-and D-amino acids. But, HPLC of their digestive fragments with trypsin and alpha-chymotrypsin differed from that of secretin. The fragments, S7-12 of P-1 and S13-21 of P-2 were determined to be different from the corresponding fragments obtained from secretin by HPLC analysis of their digestive fragments. The amino acid composition of each acid hydrolysate, following digestion with D-amino acid oxidase, was found to have less leucine or alanine content than secretin. The HPLC analysis of the fragments from P-1 and P-2 by tryptic and alpha-chymotryptic digestion showed that they are the same as those from synthetic D-Leu10 secretin or D-Ala17 secretin, respectively. Consequently, P-1 and P-2 are concluded to be the secretin diastereoisomers, D-Leu10 and D-Ala17 secretin, respectively. 相似文献
940.
H Watanabe Y Kamasaka T Higashihara T Inoue T Kuroda T Kozuka N Fujimoto Y Tada 《Clinical radiography》1989,34(12):1501-1504
We report two cases of unilateral renal angiomyolipoma. In both cases, our preoperative diagnosis was renal cell carcinoma because no low density area compatible with a fatty tissue was noted in the tumors. Histological examination revealed both tumors to be angiomyolipoma mainly composed of myomatous cells and immature fat cells. 相似文献