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Immunohistochemical, ultrastructural and immunoelectron microscopic studies of spinal cord neurofibrillary tangles (NFTs) in progressive supranuclear palsy (PSP) were performed. The spinal cord NFTs reacted with antibodies to tau protein (tau-2), ubiquitin and Alzheimer neurofibrillary tangles (ANTs, Ab 39). Ultrastructurally, the NFTs consisted of bundles of straight fibrils. In longitudinal sections, the individual NFT fibrils appeared as straight fibrils with a diameter of approximately 15 nm. In cross sections, circular structures approximately 15 nm in diameter were seen, and some had a central density. Electron microscopic examination of specimens stained with the antibodies and by the modified Bielschowsky method revealed the products of the tau, ubiquitin and ANTs immunoreactions and silver deposits on the NFT fibrils. This is the first demonstration of the ultrastructure of spinal cord NFTs in PSP.  相似文献   
3.
In order to investigate the validity of the hypothesis that acid-soluble peptides (ASP) in urinary excreta can be applied as an index of the protein catabolism of the whole body, we measured the urinary excretion of ASP in 46 normal children and in 18 children with Duchenne muscular dystrophy (DMD), in which continuous breakdown of skeletal muscle protein is presumed. The mean value of ASP in the children with DMD was significantly higher than that in normal controls. The concentration of ASP was correlated with that of 3-methylhistidine (3MH), which has been proposed as an index of muscle breakdown. This finding indicates that urinary ASP reflects the catabolism of body proteins. No correlation was observed between the concentration of ASP and that of 1-methylhistidine (1MH), which is used as an objective index of meat and fish ingestion. After the administration of bestatin, an inhibitor of leucine aminopeptidase, for 9 months, the urinary ASP concentration of children with DMD increased markedly. This increase is thought to have been directly caused by the bestatin itself. Urinary ASP is therefore apparently a more conveniently applied index of protein catabolism than is urinary 3MH, which requires the application of several restrictions. However, it should not be applied when the effect of bestatin administration is evident.  相似文献   
4.
The postprandial effect on the bioavailability of bropirimine in dogs after oral administration of bropirimine tablets (Bropirimine 250 mg Tablet) was investigated. At a dose of 500 mg bropirimine (two tablets of bropirimine 250 mg), the maximum plasma concentration under the postprandial condition was about twice that observed under the fasting condition, and the area under the plasma concentration vs time curve under the postprandial condition was also twice that under the fasting condition. The absolute oral bioavailabilities of bropirimine were 41.1% under the fasting condition and 83.5% under the postprandial condition. It is considered that the longer gastric residence time and larger volume of the gastric fluid induced by food-intake caused the increase in dissolution of bropirimine which increased the bioavailability after oral dosing of bropirimine 250-mg tablets.  相似文献   
5.
BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
6.
Eight cultured cell lines were established from human smallcell lung cancers. Every cell line showed the morphologicaland biochemical characteristics of small cell cancer. Changesin cell characteristics were observed in many of these celllines when culture conditions were changed: "oat cell type"changed to "intermediate cell type" and vice versa when serum-freemedium was changed to serum-supplemented medium; a deficiencyof vitamin A in the medium caused a change to squamous cellsand vice versa; and a tumor promoter (teleocidin B) enhancedthe adherence of these cells to the surface of plastic culturedishes. These findings provide evidence that many small celllung cancer cell lines can change their morphology with changesin the environment of the cells.  相似文献   
7.
Excretion Profiles of the Mycotoxin Deoxynivalenol, followingOral and Intravenous Administration to Sheep. PRELUSKY, D. B.,VEIRA, D. M., TRENHOLM, H. L., AND HARTIN, K. E. (1986). Fundam.Appl. Toxicol. 6, 356–363. The excretion profiles of deoxynivalenol(DON) and metabolites (DON glucuronide conjugate, 3,715-trihydroxytrichothec-9,12-diene-8-one(DOM-1), and DOM-1 glucuronide conjugate) were defined in malesheep following either intravenous (iv) or oral administrationof the toxin at levels of 0.5 and 5.0 mg DON/kg body wt, respectively.After iv dosing, urinary DON levels declined in a biphasic fashionwith an average elimination half-life (terminal phase) of 1.2hr. diminishing to baseline concentrations by 8 hr. Maximumurinary excretion rates for the two major metabolites identified(conjugated DON, conjugated DOM-1) occurred 0.5–1.5 hrafter dosing, exhibiting elimination half-lives of 2.2 and 3.1hr, respectively. Total recovery accounted for only about 66.5%of the dose: 63.0% in the urine (24.1% DON, 21.2% conjugatedDON, 0.5% DOM-1, 17.2% conjugated DOM-1) and 3.5% in bile (madeup almost completely of conjugated DOM-1). The peak biliaryexcretion rate for conjugated DOM-1 was found to occur within1 hr postdosing, which rapidly declined to baseline levels by5 hr. Following oral administration, urinary excretion ratesof the major metabolites (DON, conjugated DON, conjugated DOM-1)reached maximum 6–9 hr post-treatment, and declined exponentiallywith t values of 3.2, 4.0, and 5.0 hr, respectively. Urinaryand biliary recovery of administered DON averaged approximately7.1%: 7.0% in urine (2.1% DON, 3.6% conjugated DON, 0.06% DOM-1,1.2% conjugated DOM-1) and 0.11% in bile (predominately conjugatedDOM-1). Between 54 and 75% of the oral dose was recovered inthe feces. These findings indicate that DON and metabolitesdo not persist in the body following either a single oral orintravenous dose of DON and are rapidly excreted. However, followingiv administration, a portion of the dose (33.5%) remained unaccounted,presumably converted to unidentified metabolites. Based on theseresults it appears that metabolism is the major process of eliminationof DON in sheep.  相似文献   
8.
The metabolic behavior, clearance, and pulmonary effects ofgadolinium (Gd), one of the rare earth elements, were investigatedafter single intratracheal instillation of gadolinium chloride(GdCl3) in male Wistar rats. There was a dose-related increasein Gd content of lung tissue. Gd content in the supernatantof bronchoalveolar lavage fluid (BALF) did not exceed 5 µgGd/ BALF even at a dose of 100 µg Gd/rat. Gd in the lungtissue decreased very slowly with a biological half-life of136 days at a dose of 50 µg Gd/rat. On the other hand,Gd content in the super natant of BALF was not detectable after31 days. These results suggest that intratracheally instilledGd can be retained in epithelial lining fluid only to a limitedextent as soluble forms and is deposited in the lung tissueprobably in insoluble forms which are metabolized very slowly.Calcium (Ca) content in BALF increased more rapidly than othertoxicological indices such as lactate dehydrogenase activity,protein concentration, and inflammatory cell counts. In thelung tissue, levels of Ca in Gd-instilled groups did not differfrom the control value. Although these data suggest that theorigin of Ca may be blood plasma, biological and/or toxicologicalsignificance of increased Ca is not known. The number of neutrophilsreached the maximum at 12 hr after instillation, indicatingthat Gd has the potency to cause acute lung toxicity. Summarizingthe observation, Gd instilled intratracheally into rats wasdeposited in the lung tissue in nonsoluble forms with an extremelylong half-life, while the metal caused a rapid and selectiveinfiltration of serum Ca before acute lung toxicity.  相似文献   
9.
目的建立大鼠血浆中重组E.coli L-天冬酰胺酶的抗体夹心酶联免疫吸附测定法,并进行药代动力学研究。方法应用重组E.coli L-天冬酰胺酶免疫家兔,分离IgG,用DEAE-纤维素柱色谱纯化,辣根过氧化物酶标记抗体,建立抗体夹心酶联免疫吸附法,测定大鼠血浆中重组E.coli L-天冬酰胺酶浓度。结果方法的线性范围为1~64 U·L-1,血药浓度与时间的关系符合二房室模型,初期和末端的T1/2分别为0.50~0.57 h和2.45~3.02 h,AUC与剂量成正比。结论建立的抗体夹心酶联免疫吸附法在灵敏度、特异性、线性范围、精密度和回收率等方面,满足药代动力学研究要求。实验方法和重组E.coli L-天冬酰胺酶在大鼠中的药代动力学参数为临床研究提供了手段和依据。  相似文献   
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