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91.
A rapid and sensitive method is presented for the determination of micro-quantities (1 to 100 μg) of N-methyl carbamates as dinitrophenyl methylamine (DNP-MA) by electron capture gas liquid chromatography (GLC). The method described is characterized by rapidity and simplicity of procedure due to an improvement made in the present investigation, i.e., hydrolysis of an N-methyl carbamate and dinitrophenylation of the resulting methylamine with 2, 4-dinitro-1-fluorobenzene (DNFB) were accomplished simultaneously in a single reaction mixture. A novel approach was also made to eliminate unreacted DNFB by conversion to dinitrophenyl glycine (DNP-glycine).  相似文献   
92.
Molecular formula C25H37–39NO4 was assigned to Piericidin A. Through the examination of the ultraviolet, infrared and n.m.r. spectra and of chemical evidences, it was shown that Piericidin A contains one secondary alcohol, one acidic hydroxyl group, two methoxyl groups, tri- and tetra-substituted conjugated dienes and one polysubstituted heteroaromatic ring.  相似文献   
93.
An NAD linked formate dehydrogenating enzyme which catalyzed the last step of methanol oxidation system was extracted from the methanol-grown Kloeckera sp. No. 2201. The specific activity of the enzyme in the extract of methanol-grown cells was found to be considerably higher than that of the glucose-grown cells. The enzyme was purified about 35-fold from the extract of methanol-grown cells by heat treatment, column chromatographies on DEAE-cellulose and on hydroxylapatite, and Sephadex G-200 gel filtration. The purified enzyme was shown to be homogeneous by analyses with electrophoresis and ultracentrifuga-tion. The purified enzyme was a kind of NAD: formate oxidoreductase (EC, 1.2.1.2) which catalyzed specifically the oxidation of formate to carbon dioxide. The Km values were 22 mm for formate and 0.1 mm for NAD. The enzyme was inactivated by potassium cyanide, sodium azide, and p-chloromercuribenzoate but not by any metal-chelating reagents tested. Other general properties of the enzyme were also investigated.  相似文献   
94.
S-1358 was rapidly absorbed, metabolized and readily excreted via urine and feces from orally dosed rats. Excretion of radioactivity was almost complete within 4 days. The radioactivity was distributed mainly in stomach, intestines, liver and kidneys. It seems that S-1358 and its metabolites do not persist in organs and tissues following a single oral dosing.

Major urinary metabolites of the benzyl-labeled S-1358 were p-(1,1-dimethyl-2-hydroxyethyl)benzyl methyl sulfide [B], p-(1,1-dimethyl-2-hydroxyethyl)benzyl methyl sulfone [A], p-(1-methyl-1-carboxylethyl)benzyl methyl sulfide [D], p-(1-methyl-1-carboxylethyl)benzyl methyl sulfone [C] and their glucuronide conjugates. Fecal metabolites were S-n-butyl S′-(1, 1-dimethyl-2-hydroxyethyl)benzyl N-3-pyridyldithiocarbonimidate [MR], A, B, C and D. These metabolites were also found in the bile. The pyridine-labeled S-1358 gave rise to 2-(3′-pyridylimino)-4-carboxylthiazolidine [HM] and 3-aminopyridine [AP] in the urine, and MR and AP in the feces. Intact S-1358 was a major component of the fecal radioactivity.  相似文献   
95.
Using 3-(3′,5′-dichlorophenyl)-5,5-dimethyloxazolidine-2,4-dione labeled with 14C or 3H, absorption, excretion, and tissue distribution in male Wistar rats were studied, and metabolites excreted were identified. At the dosage rates of 100, 300, 1000 and 3000 mg/kg, the maximum excretion of orally administered radioactivity occurred within 24 hr. Increase in the dosage rate was paralleled by decrease in the proportion of urinary elimination. Essentially all the radioactivity was excreted in 2 weeks. DDOD level was generally low in most tissues. Adipose tissue contained higher radioactivity compared with others. Most of the urinary metabolites identified were characterized by hydroxylation at the 4′ position of the benzene ring moiety, and hydrolytic or oxidative modification of the oxazolidine ring portion.  相似文献   
96.
The products of several Bacillus strains were investigated on rabbit serum calcium decreasing, oxytocic and toad heart function promoting activities. These products were obtained from the clear supernatant fluid of the culture medium after the cells were removed by centrifugation.

For the production of rabbit serum calcium decreasing substance, Bacillus subtilis K and Bacillus natto No. 8 were found to be usefull, Bacillus megaterium KM, Bacillus cereus var. mycoides and Bacillus subtilis K produced oxytocic principle. Bacillus subtilis K, Bacillus brevis and Bacillus megaterium KM also produced toad heart function promoting factor.

A procedure was developed to obtain the electrophoretically homogenous rabbit serum calcium decreasing substance from culture filtrate of Bacillus subtilis K. The crude substance was obtained as isoelectric precipitate by adjusting the culture filtrate to pH 3.0. The crude substance was purified by gel filtration on a Sephadex G-75 column, isoelectric fractionation and chromatography on DEAE-cellulose column. The purified preparation was shown to be homogenous by Tiselius electrophoresis but was separated into two bands by polyacrylamide electrophoresis. The chemical analysis of this biologically active substance indicated this substance to be a lipoprotein. The substance decreased rabbit serum calcium level about 12% at 6~8hr after intravenous injection (dose; 0.5 mg/kg body weight).  相似文献   
97.
In recent decades, the extent of Sasa palmata-dominant communities has increased in Sarobetsu Mire in northern Hokkaido, Japan, replacing the original Sphagnum bog vegetation. However, this marked increase in distribution of Sasa in the mire has not been formally documented or investigated in detail. Using aerial photo-interpretation, the present study updated the distribution maps of Sasa communities, showing the changes that have occurred to these communities between 1977 and 2003. The results revealed that the extent of Sasa communities has increased by 15.8 % from 6.60 km2 in 1977 to 7.64 km2 in 2003. The most marked increase occurred on the ground associated with drainage channels, although the oldest channels were constructed more than half a century ago, suggesting that some responses to the drainage of peat bog ecosystems may take a considerable period of time before becoming particularly evident.  相似文献   
98.

Background

D-Serine, an endogenous co-agonist of the N-methyl-D-aspartate (NMDA) receptor, is synthesized from L-serine by serine racemase (SRR). Given the role of D-serine in both neurodevelopment and the pathophysiology of schizophrenia, we examined whether neonatal disruption of D-serine synthesis by SRR inhibition could induce behavioral abnormalities relevant to schizophrenia, in later life.

Methodology/Principal Findings

Neonatal mice (7–9 days) were injected with vehicle or phenazine methosulfate (Met-Phen: 3 mg/kg/day), an SRR inhibitor. Behavioral evaluations, such as spontaneous locomotion, novel object recognition test (NORT), and prepulse inhibition (PPI) were performed at juvenile (5–6 weeks old) and adult (10–12 weeks old) stages. In addition, we tested the effects of D-serine on PPI deficits in adult mice after neonatal Met-Phen exposure. Finally, we assessed whether D-serine could prevent the onset of schizophrenia-like behavior in these mice. Neonatal Met-Phen treatment reduced D-serine levels in the brain, 24 hours after the final dose. Additionally, this treatment caused behavioral abnormalities relevant to prodromal symptoms in juveniles and to schizophrenia in adults. A single dose of D-serine improved PPI deficits in adult mice. Interestingly, chronic administration of D-serine (900 mg/kg/day from P35 to P70) significantly prevented the onset of PPI deficits after neonatal Met-Phen exposure.

Conclusions/Significance

This study shows that disruption of D-serine synthesis during developmental stages leads to behavioral abnormalities relevant to prodromal symptoms and schizophrenia, in later life. Furthermore, early pharmacological intervention with D-serine may prevent the onset of psychosis in adult.  相似文献   
99.
Some patients with idiopathic pulmonary fibrosis (IPF) do not have honeycombing on high-resolution computed tomography (HRCT) at their initial evaluation. The clinical course and sequential changes in HRCT findings in these patients are not fully understood. We reviewed the cases of 43 patients with IPF without honeycombing on initial HRCT from institutions throughout Japan. All patients were diagnosed with IPF based on a surgical lung biopsy. Multidisciplinary discussions were held five times between 2011 and 2014, to exclude alternative etiologies. We evaluated the sequential changes in HRCT findings in 30 patients with IPF. We classified these 30 patients into three groups based on their HRCT patterns and clarified the clinical characteristics and prognosis among the groups. The patterns of all 30 patients on initial HRCT corresponded to a possible usual interstitial pneumonia (UIP) pattern which was described in the 2011 International Statement. On long-term follow-up (71.0±38.7 standard deviation [SD] months), honeycombing was seen in 16 patients (53%, the HoneyCo group); traction bronchiectasis or cysts without honeycombing was observed in 12 patients (40%, the NoHoneyCo group), and two patients showed no interval change (7%, the NoChange group) on HRCT. The mean survival periods of the HoneyCo and NoHoneyCo groups were 67.1 and 61.2 months, respectively (p = 0.76). There are some patients with IPF whose conditions chronically progress without honeycombing on HRCT. The appearance of honeycombing on HRCT during the follow-up might not be related to prognosis.  相似文献   
100.
During embryonic development of the peripheral nervous system (PNS), Schwann cell precursors migrate along neuronal axons to their final destinations, where they will myelinate the axons after birth. While the intercellular signals controlling Schwann cell precursor migration are well studied, the intracellular signals controlling Schwann cell precursor migration remain elusive. Here, using a rat primary cell culture system, we show that Dock8, an atypical Dock180-related guanine-nucleotide exchange factor (GEF) for small GTPases of the Rho family, specifically interacts with Nck1, an adaptor protein composed only of Src homology (SH) domains, to promote Schwann cell precursor migration induced by platelet-derived growth factor (PDGF). Knockdown of Dock8 or Nck1 with its respective siRNA markedly decreases PDGF-induced cell migration, as well as Rho GTPase activation, in precursors. Dock8, through its unique N-terminal proline-rich motif, interacts with the SH3 domain of Nck1, but not with other adaptor proteins composed only of SH domains, e.g. Grb2 and CrkII, and not with the adaptor protein Elmo1. Reintroduction of the proline-rich motif mutant of Dock8 in Dock8 siRNA-transfected Schwann cell precursors fails to restore their migratory abilities, whereas that of wild-type Dock8 does restore these abilities. These results suggest that Nck1 interaction with Dock8 mediates PDGF-induced Schwann cell precursor migration, demonstrating not only that Nck1 and Dock8 are previously unanticipated intracellular signaling molecules involved in the regulation of Schwann cell precursor migration but also that Dock8 is among the genetically-conservative common interaction subset of Dock family proteins consisting only of SH domain adaptor proteins.  相似文献   
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