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931.
RB Ramsey NL Banik PT Ramsey ML Cuzner T Scott AD Dayan AN Davison 《Canadian Metallurgical Quarterly》1976,30(1):95-111
Neurochemical and neuropathological studies have been made of a 10-day-old child who suffered from a sudanophilic leukodystrophy. The brain white matter contained abundant sudanophilic material. The patient's grey matter total cholesterol content was 30% higher than whole brain tissue derived from a comparable control. White matter cholesterol content was more than double the control value. Nearly 80% of the white matter cholesterol was esterified. Subcellular fractionation of the white matter resulted in a "floating fraction" rich in cholesteryl ester. The steryl ester fatty acid composition was not typical of control tissue or demyelinating tissue. Patient phospholipid fatty acid composition patterns differed from control, but white matter galactolipid fatty acid composition appeared normal. Cholesteryl ester hydrolase activity appeared normal. Myelin and myelin-like fractions, isolated from diseased and normal brain tissue, were of a primitive developing nature but appeared to be comparable. The findings indicate a neonatal sudanophilic leukodystrophy which doubtless began in prenatal life and which was rich in cholesteryl ester. The aetiology of the leukodystrophy is unknown. 相似文献
932.
Nuclear magnetic resonance studies of D2O-substrate exchange reactions catalyzed by glutamic pyruvic and glutamic oxaloacetic transaminases 总被引:1,自引:0,他引:1
Nuclear magnetic resonance studies in D2O (greater than 90%) with glutamic pyruvate transaminase (GTP) (2.6.1.2) demonstrate that this enzyme catalyzes the rapid exchange of both the alpha and beta hydrogens of L-alanine, the exchange of only one alpha hydrogen of glycine, and the beta hydrogens of pyruvate and fluoropyruvate. When the beta hydrogens of L-alanine undergo the enzyme-catalyzed exchange, the product may have 1, 2 or 3 of beta hydrogens exchanged. The exchange is stimulated by the addition of catalytic amounts of copartner of transaminations reaction. A mechanism is proposed for an extension of the conjugated system to include the alpha and beta carbons to explain the labilization of the beta hydrogens. 相似文献
933.
The association between psychopathology at treatment entry and the amount of treatment services received was evaluated in 104 alcohol-dependent and 100 cocaine-dependent male veterans treated for 1 month in either a day hospital or inpatient program. Measures of psychopathology included the Addiction Severity Index psychiatric composite score, the presence or absence of an antisocial personality disorder diagnosis, and the total number of additional lifetime or current psychiatric diagnoses. Patients with higher admission Addiction Severity Index psychiatric composite scores received more medical, alcohol, family/social, and psychiatric services. There was also preliminary evidence that patients who received more treatment showed greater improvement 7 months after admission. The relationships between the other measures of psychopathology and treatment services failed to achieve overall statistical significance, although significant relationships were found in several individual areas. 相似文献
934.
935.
RB Rutherford J Wahle M Tucker D Rueger M Charette 《Canadian Metallurgical Quarterly》1993,38(7):571-576
Osteogenic protein-1 (OP-1, BMP-7), a member of the transforming growth factor-beta supergene family, induces cartilage and bone formation when implanted in intra- and extraskeletal sites in vivo. The human OP-1 gene has been cloned and biologically active recombinant OP-1 homodimers (hOP-1) produced. The amount of bone induced by hOP-1 in vivo is related to the amount of protein implanted. Dentine possesses bone morphogenetic protein (BMP) activity. Impure material from allogenic bone with BMP activity induced reparative dentine formation in dogs. The objective of this study was to determine if the amount of reparative dentine stimulated by hOP-1 is related to the amount of protein utilized in direct pulp-capping experiments. Freshly exposed molar and premolar pulps were treated with varying amounts of a complex comprising hOP-1 and a carrier matrix of purified bovine type-1 collagen powder (CM) moistened with sterile saline. Reparative dentine was present in all hOP-1/CM treated teeth (12 of 15) that remained sealed for the 6 weeks' healing. Substantially more new dentine was present in teeth treated with hOP-1/CM than in those treated with Ca(OH)2 paste and the amount of reparative dentine formed was proportional to the amount of hOP-1/CM (P < 0.05). No reparative dentine formed in collagen carrier or untreated teeth. The appearances of the new tissue suggested that much of the mass of the hOP-1/CM was replaced first by a pulp-like connective tissue, which mineralized to form reparative dentine.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
936.
RB Gibbs 《Canadian Metallurgical Quarterly》1996,16(3):1049-1055
Quantitative in situ hybridization techniques were used to compare relative cellular levels of choline acetyltransferase (ChAT) mRNA in different regions of the female rat basal forebrain at different stages of the estrous cycle and at different time points after the administration of physiological levels of estrogen and progesterone. Significant fluctuations in relative levels of ChAT mRNA were detected during the course of the estrous cycle. In the medial septum (MS) and striatum, the highest levels of ChAT mRNA were detected on diestrus 1. Fluctuations in the nucleus basalis magnocellularis (NBM) were highly variable, with the highest levels detected on diestrus 2. In ovariectomized animals, significant increases in ChAT mRNA were detected in the MS, NBM, and striatum within 1-3 d after a single administration of estradiol. In addition, the effects of estradiol on ChAT mRNA expression in the NBM and striatum were significantly enhanced by the subsequent administration of progesterone. The magnitude and timing of the effects of steroid replacement were consistent with the magnitude and time course of the fluctuations detected during the course of the estrous cycle. These data demonstrate that estrogen and progesterone can increase basal forebrain levels of ChAT mRNA significantly in specific regions of the rat basal forebrain, that the magnitude and time course of the effects vary between different subpopulations of cholinergic neurons, and that the effects are associated with changes in the functioning of specific basal forebrain cholinergic neurons across the estrous cycle. 相似文献
937.
1. The aim of this study was to characterize adenosine receptors located in the nucleus tractus solitarius (NTS) that mediate decreases in blood pressure in the anaesthetized rat. To determine the adenosine receptor subtype involved, a range of selective agonists and antagonists were studied and their relative potencies evaluated. 2. The rank order of agonist potency in inducing decreases in diastolic blood pressure was N6-cyclopentyladenosine (CPA) > N6-cyclohexyladenosine (CHA) > N-ethyl-carboxamidoadenosine (NECA) > or = 2-phenylaminoadenosine (CV1808) > 2-p-(carboxyethyl)phenethylamino-5' N-ethylcarboxamidoadenosine (CGS 21680) > N6-(2-(4-aminophenyl)ethyl)-adenosine (APNEA). 3. The hypotensive action of CPA following microinjection into the NTS was antagonized by i.v. infusions (50 micrograms kg-1 min-1) of adenosine receptor antagonists, 8-cyclopentyl-1,3 dipropylxanthine (DPCPX), 8-phenyltheophylline (8-PT), 8-(p-sulphophenyl)theophylline (8-SPT), and 1,3-dipropyl-8-N-(2-diethylamino)ethyl)-N methyl-4-(2,3,6,7-tetrahydro-2,6-dioxo) benzenesulphonamidexanthine (PD 115199). The antagonist potency order was DPCPX > PD115199 > or = 8-PT. Intravenous infusion of 8-SPT had no effect on blood pressure responses to microinjection of CPA into the NTS. 4. The results suggest that adenosine A1 receptors in the NTS mediate hypotensive responses in the anaesthetized rat preparation. 相似文献
938.
The periconceptional intake of 400 micrograms of folic acid can prevent 50-70% of neural tube defects. It is difficult to achieve this intake with diet alone, even with the recently approved levels for grain-food fortification. Therefore, a daily multivitamin with folic acid is recommended for all women of childbearing potential. Obstetrician-gynecologists should exercise every opportunity to educate their patients to this end. Although raised as a concern, the potential of masking the megaloblastic anemia of pernicious anemia is unlikely with these levels of supplementation, and considering the rarity of the disease in women of reproductive age. 相似文献
939.
Twenty-six patients (35 feet) underwent partial plantar fasciectomy with neurolysis of the nerve to the abductor digiti quinti muscle. Nonsurgical treatment for plantar fasciitis had been unsuccessful in these patients. Patients were followed after surgery for an average of 37.5 months. Six patients were male and 20 patients were female; the average age was 49 years. All patients had failed to respond to nonsurgical treatment for an average of 21.5 months. In addition to routine history and physical examination patients were evaluated before and after surgery with a subjective foot rating system, and a detailed questionnaire was used to assess post-operative functional outcome. Thirty-two patients (92%) had a satisfactory functional outcome, and three patients (8%) had an unsatisfactory result (21 excellent, 11 good, 3 fair, 0 poor). The Maryland Foot Score increased from a preoperative average of 74.8/100 points to a postoperative average of 90.6/100 points. Four patients (11%) had postoperative complications, including superficial wound infection (two patients), deep venous thrombosis (one patient), and superficial phlebitis (one patient), all of which resolved uneventfully with treatment. Ten patients (28.6%) reported some degree of heel pain after surgery. All 10 patients denied limitation in activity related to postoperative pain. The average period before return to daily activity and restricted work duty was 5.6 weeks and to full work duty without restriction was 8.7 weeks. Although the length of time for partial or complete resolution of symptoms is variable, a successful treatment outcome can be expected in most patients who are treated for recalcitrant plantar fasciitis. 相似文献
940.