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11.
BACKGROUND: Noni (Morinda citrifolia L.) leaves have a documented history of food use. However, previous safety and antinutrient studies are absent. The current investigation was conducted to assess the utility of noni leaves as food. RESULTS: No evidence of toxicity or differences in weight gain were observed in acute, subacute, and subchronic oral toxicity tests of ethanol–water (1:1 v/v) and hot‐water extracts of noni leaves in mice at doses of 2000, 200, and 20 mg kg?1 body weight, respectively. Acute systemic anaphylaxis tests of the ethanol–water (4:1 v/v) and hot‐water extracts were negative. Further, leaf proteins were readily digested in simulated gastric fluid. Tannic acid concentrations in frozen and dried leaf were 1.6 and 25.8 g kg?1, respectively. Phytic acid was not detected in the raw leaf (<1 g kg?1). The average oxalic acid content was 1 g kg?1 and was fairly uniform among 22 leaf samples from 11 islands throughout French Polynesia. Similarly, campesterol, stigmasterol, and β‐sitosterol content did not vary widely, suggesting low inter‐island content variability. CONCLUSIONS: The apparent lack of toxicity of the leaves and the hardiness of the plant make it ideal for further agricultural development, especially where sustained growth of other food crops is difficult. Copyright © 2007 Society of Chemical Industry  相似文献   
12.
The number of cases of prostate carcinoma (PCA) is steadily inceasing in Japan. The clinical application of a reliable tumor marker, prostate specific antigen (PSA) for the diagnosis, as well as the increasing elderly population in Japan may account for this increase. The subjects were patients at the Nara Medical University and its affiliated hospitals; 1) 687 cases without PCA were evaluated for age-specific PSA and the incidence of abnormal PSA following urological manipulations, 2) 135 cases with histological proven BPH by transurethral resection of prostate (TUR-P) were examined for PSA density (PSAD) and positive PSA rate in BPH, 3) 135 cases receiving a needle biopsy with suspicion of PCA were examined for the efficacy of PSA and PSAD and other parameters, and 4) 459 PCA cases treated between 1988 and 1994, were examined for specific PSA and PSAD values by stage and degree of cell differentiation. The PSA assay used in this study was MARKIT-M PA (normal range < or = 3.6 ng/ml). The PSA was decreased gradually with age in non-PCA patients, and abnormal PSA was found in 5.5% of these patients following manipulations. The average PSA was 2.95 +/- 2.03 ng/ml in 130 BPH patients (mean age: 71.1 +/- 7.0 years old. and average prostate volume: 32.9 +/- 16.1 ml). And abnormal PSA level (more than 3.61 ng/ml) was found in 22.3%. The mean PSAD was 0.1.0 +/- 0.06, and PSAD was below 0.15 in 86.1% of these BPH cases. Among the 135 cases receiving a needle biopsy, 33 cases had PSA values between 3.61 and 10.0 ng/ml. Of these cases, PCA was found in 18.5% of the 27 cases with a PSAD below 1.5, and in 33.3% of the 6 cases with a PSAD over 1.5. PSA and PSAD were proportionally increased with stage, and a significant difference in the PSA value was observed between stage B1 and B2, and stage C and D (P < 0.05). However, PSA and PSAD values were not significantly correlated with the cell differentiation in PCA stage A2-C. In total, PSA was 18.1 ng/ml in well, 23.9 ng/ml in moderately and 35.9 ng/ml in poorly differentiated type PCA. The positive rate of PSA was 22.3, 65.4 and 83.5%, that of prostate acid phosphatase (PAP) was 10.0, 17.8 and 45.8%, and that of GSM was 25.0, 14.7 and 68.4%, in BPH, stage A PCA and stage BPCA, respectively. In conclusion, PSA is the most reliable tool in the diagnosis of localized PCA. However, the differential diagnosis of BPH and localized PCA is difficult when the PSA value is between 3.61 and 10.0 ng/ml, and accurate staging of localized PCA is difficult with PSA or PSAD alone. At present, it is necessary to use all possible tools for the early detection of localized PCA, and to perform the needle biopsy in all PCA-suspicious cases.  相似文献   
13.
A dental student developed swelling of the lips and peri-oral urticaria, immediately after placement of a dental rubber dam during a chairside demonstration of clinical dentistry. A provisional diagnosis of a Type I hypersensitivity reaction to natural rubber latex was made and an appointment organised for specialist investigations. The student reported an atopic history and allergy to peanuts. A Radioallergosorbent Test (RAST), to measure Ig-E antibodies to latex, was positive. The dental student was given advice concerning the avoidance of natural rubber latex. Dental staff must be aware of potentially serious reactions to natural rubber latex in the dental surgery.  相似文献   
14.
ZnO nanowires were grown by an ultrasonic spray pyrolysis technique. The aspect ratio and size of the wire were dependent mainly on the pH value of a precursor solution and the growth temperature. By high-resolution transmission electron microscopic analysis and photoluminescence measurements, it was confirmed that the nanowires are monocrystalline with good optical quality.  相似文献   
15.
Fusarium moniliforme strain MS31 can oxidize propylbenzene to (R)-1-phenylpropanol with what may be a cytochrome P450. Hydroxylation of propylbenzene needed molecular oxygen, and NADPH as a coenzyme gave a higher yield than NADH. The hydroxylation proceeded further when FAD and FMN were added than in their absence, suggesting that the enzyme was a flavo-protein. Carbon monoxide inhibited the hydroxylation, as did other cytochrome P450 inhibitors such as SKF 525A and miconazole. These characteristics matched those of a microsomal cytochrome P450 monooxygenase system that contained NADPH-cytochrome P450 reductase.  相似文献   
16.
Flow cytometry used in combination with single-cell sorting is a powerful technique for the identification and isolation of microbial cells with particular characteristics, especially when such cells grow more slowly than other cells in a large heterogeneous population. Many applications of flow cytometry with cell sorting, originally used by specialists studying mammalian cells, have been modified so that microorganisms also can be evaluated. The methods can now be used more widely because of the increasing availability of the expensive equipment. There are means for the fluorescence detection of a wide variety of properties, such as amounts of various cell components, specific sequences of peptides and nucleotides, cell functions, and enzyme activities. From the extensive literature, representative reports of an assortment of uses of flow cytometry with cell sorting are reviewed in this article, intended to introduce the technique and its many advantages to microbiologists.  相似文献   
17.
By utilizing "multiinformation dyes (MIDs)", which have plural spectral change characteristics such as an absorption maximum wavelength (λ(max)) shift based on a polarity change and an absorbance change due to protonation, novel λ(max)-tunable ion-selective optodes were proposed and prepared by employing MIDs with membrane solvents having different polarities. For controlling the detecting λ(max) of the optode, the novel polar membrane solvent [2-[[6-(2-nitrophenoxy)hexyl]oxy]methyl]isobutane-1,3-diol was designed and synthesized, which was used together with a typical membrane solvent nitrophenyl octyl ether. By mixing these two membrane solvents, the λ(max) position of the optode detection wavelength can be shifted and controlled and was successfully applied to a λ(max)-tunable Li(+)-selective optode based on a highly Li(+)-selective ionophore TTD14C4. The λ(max) tuning technique is useful for preparing an optode system using a low-cost light source such as a light-emitting diode or a popular laser.  相似文献   
18.
Photoautotrophic cultures of the host and transformed cells of the liverwort, Marchantia polymorpha, were examined. In cultures in flat glass flasks under various light intensities, it was found that the growth rates of both the cells increased with increase in light intensity in the range of 0 to 25 W/m2, but further increase in light intensity caused photoinhibition of the growth of the cells. Cultures of both the types of cells under light-controlled conditions using an externally illuminated bioreactor were carried out taking into consideration the inhibition of cell growth by excessive light and the light intensity distributions in the cell suspensions. In these cultures, 2.1 (transformed cells) and 3.3 (host cells) kg dry cell weight per m3 were harvested at culture times of 9.0 and 10 d, respectively. These values were larger than those obtained in cultures of the respective cells at a fixed incident light intensity of 25 W/m2.  相似文献   
19.
The management of avascular necrosis of the capitellum of the adolescent elbow continues to be a dilemma. This article is a critical retrospective analysis of 12 pediatric patients (mean age at surgery 14.5 years) who underwent arthroscopic debridement alone followed by early range of motion. Follow-up at a mean of 3.2 years (range, 2.0 to 5.7 years) indicated that the average flexion contracture improved from 23 degrees preoperatively to 10 degrees postoperatively. All patients had remodeling of the capitellum by plain radiographs; however, five patients had associated enlargement of the radial head. Eleven patients had minimal mechanical symptoms after the procedure and were highly satisfied. One patient had substantial enlargement of the radial head with continued loss of supination and mechanical symptoms requiring radial head resection 2 years after the index procedure. Five patients had a triangular avulsion fragment present off the lateral capsule. A statistically significant worse subjective outcome was associated with the presence of this fragment (P < .005). There were no complications.  相似文献   
20.
Buprenorphine (BN) is a thebaine derivative with analgesic properties. To identify and characterize the cytochrome P450 (CYP) enzyme(s) involved in BN N-dealkylation, in vitro studies using human liver microsomes and recombinant human CYP enzymes were performed. Norbuprenorphine formation from BN was measured by a simple HPLC-UV assay method, without extraction. The BN N-dealkylation activities in 10 human liver microsomal preparations were strongly correlated with microsomal CYP3A-specific metabolic reactions, i.e. triazolam 1'-hydroxylation (r = 0.954), midazolam 1'-hydroxylation (r = 0.928), and testosterone 6beta-hydroxylation (r = 0.897). Among the eight recombinant CYP enzymes studied (CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4), only CYP3A4 could catalyze BN N-dealkylation. The apparent KM value for recombinant CYP3A4 was similar to that for human liver microsomes (23.7 vs. 39.3 +/- 9.2 microM). The demonstration of BN N-dealkylation by recombinant CYP3A4 and the agreement in the affinities (apparent KM values) of human liver microsomes and recombinant CYP3A4 provide the most supportive evidence for BN N-dealkylation being catalyzed by CYP3A4.  相似文献   
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