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501.
Two 4 week old infants are reported who suffered apparent life threatening events (ALTE) while being cradled in adult arms. The events, which could be reproduced under controlled circumstances, were not associated with any struggling by the infants. Alteration of infant holding practices in both cases resulted in cessation of the events. A case of cardiorespiratory arrest during breast feeding in an 8 week old infant that was unnoticed by her mother is also described. These cases suggest that certain infants may not respond normally to airway occlusion while being held or nursed, and show that careful study of the events surrounding ALTE may reveal contributing environmental factors. If ALTE occur around feeding time, observation of how caretakers place the infant during and after feeding may be informative. 相似文献
502.
504.
Tan XQ Chen HS Liu RH Tan CH Xu CL Xuan WD Zhang WD 《第二军医大学学报》2006,27(5):513-513
Seven lignans having a diarylhydroxybutyrolactone skeleton were isolated from the leaves and stems of Trachelospermum jasminoides (Lindl.) Lem. Their structures were elucidated to be nortrachelogenin 8'-O-beta-D-glucopyranoside (1), nortrachelogenin 5 '- C- beta-D-glucopyranoside (2), trachelogenin amide (3), nortracheloside, trachelogenin, tracheloside, and trachelogenin 4'- O- beta-gentiobioside, respectively, on the basis of spectroscopic analyses. 相似文献
505.
A new series of 3-(6-substituted-benzothiazol-2-yl)-6-phenyl-[1, 3]-oxazinane-2-thiones (4a-j) has been synthesised using an appropriate synthetic route (Scheme 1) and characterised by elemental analyses and spectral (IR, (1)HNMR, (13)C NMR, and EI MS) data. The anticonvulsant activity of all the title compounds (4a-j) was evaluated against Maximal Electroshock (MES) induced seizures and furthermore the most potent compounds were evaluated against subcutaneous pentylenetetrazole (sc PTZ) induced seizures model in mice. The neurotoxicity was assessed using the rotorod procedure. All the test compounds were administered intraperitoneally at various dose levels ranging from 30-200 mg/kg body wt and the median effective dose (ED(50)), median toxic dose (TD(50)), and protection index (PI) values were determined (Table 2). Among the compounds tested, the 3-(6-dimethylaminobenzothiazol-2-yl)-6-phenyl-[1, 3]-oxazinane-2-thiones (4j) was found to be the most potent (ED(50): 9.85 and 14.8 in MES model and 12 and 17 in scPTZ model at t = 0.5 h and 4 h, respectively, and TD(50) 42.8 and 44 at t = 0.5 h and 4 h, respectively, which has been found to be significant at p < 0.01 with respect to reference standard phenytoin) with protection index (PI) 4.85. 相似文献
506.
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508.
Nuclear genes of human complex I of the mitochondrial electron transport chain: state of the art 总被引:4,自引:3,他引:4
Smeitink JA; Loeffen JL; Triepels RH; Smeets RJ; Trijbels JM; van den Heuvel LP 《Human molecular genetics》1998,7(10):1573-1579
The mitochondrial electron transport chain (mtETC) consists of four
multi-subunit enzyme complexes. Complex I or NADH:ubiquinone
oxidoreductase, the largest mtETC multisubunit complex, consists of
approximately 41 subunits. Seven of these subunits are encoded by the
mitochondrial genome, the remainder by the nuclear genome. Among the
mitochondriocytopathies, complex I deficiencies are encountered frequently.
Although some complex I deficiencies have been associated with
mitochondrial DNA mutations, the genetic defect has not been elucidated in
the majority of complex I-deficient patients. It is expected that many of
these patients have mutations in the nuclear- encoded subunits of this
complex, so vital for cellular energy production. After a brief summary of
the current knowledge of complex I from cow, bacteria and fungi, this
review presents the state of the art of the knowledge of the human
nuclear-encoded complex I genes which, in the last 18 months, has made
enormous progress. At present, the complete gene structure of four subunits
and the cDNA structure of 18 of the 34 complex I nuclear-encoded subunits
are known. Mapping of these subunits shows a random distribution over the
chromosomes. The chromosomal localization is known for 14 complex I genes.
Recently, the first mutation, a 5 bp duplication in the 18 kDa (AQDQ)
subunit, has been reported. We expect that within 1 year all human
nuclear-encoded complex I subunits will be cloned. Mutational analysis of
these subunits is warranted in complex I-deficient patients and will not
only be important for genetic counselling but will also extend the
knowledge regarding the functional properties of the individual human
complex I subunits.
相似文献
509.
According to a recent hypothesis the therapeutic effects of antidepressants might be related to acute or cumulative suppression of NREM sleep intensity. This intensity has been proposed to be expressed in the EEG power density in NREM sleep. In the present study the relationship was examined between the changes of EEG power density in NREM sleep and the changes in clinical state in 16 depressed patients during treatment with citalopram, a highly specific serotonin uptake inhibitor. A one-week wash-out period was followed by 1 week of placebo administration, a medication period of 5 weeks, and a one-week placebo period. In order to minimize systematic influences of sleep duration and NREM-REM sleep alterations, EEG power was measured over the longest common amount of NREM sleep stages 2, 3 and 4 (91.5 min). During the last treatment week and the week after withdrawal, a significant decrease of EEG power as compared to baseline was found in the 8-9 Hz frequency range. No clear-cut change, however, was observed in the EEG power of the delta frequency range (1-4 Hz), which is considered to be the principle manifestation of NREMS intensity. Furthermore, no relationship between changes in EEG power density and changes in clinical state could be demonstrated. 相似文献
510.
The intake of nutrients over a five day period was studied in 23 children whose atopic eczema was being treated by the avoidance of multiple foods. The results were compared with those from 23 healthy control children not on a diet. Significantly low intakes of calcium were discovered in 13 patients but not in controls. Avoidance of multiple foods is potentially hazardous and requires continued paediatric and dietetic supervision. 相似文献