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991.
1'-4 Thio-N-acetyllactosamine was chemically synthesized as a galactosidase-stable substrate for alpha(1-->3)fucosyltransferase. The product of enzymatic fucose addition was confirmed to be the thio-Le X analog.  相似文献   
992.
A 17-year old boy with primary mental retardation of unknown aetiology and cyclic vomiting syndrome (CVS) is reported. Missing an organic cause of the episodes therapeutic procedures remained symptomatic for a 15 years time period. The report focusses the CVS as a regressive mechanism triggered by a mental retardation of the child which permanently disturbed the interaction between parents and child. Psychotherapeutic approach was successful in the following respects: The advantage by illness to vomit at home was continuously reduced by admitting the boy to a hospital at every ongoing attack. Hypnotherapeutic techniques were able to substitute the "malign" regression (CVS) successively by inducing a "benign" kind of regression. Family therapy could induce new and more intense non-verbal patterns of communication which where hitherto unknown in this family.  相似文献   
993.
Mutations, other than dominant lethals, were accumulated on wild type second chromosomes (+) of Drosophila melanogaster during exposure to 50 Hz sinusoidal alternating magnetic fields of 0.5 or 5 mT (rms) for 40 generations by the Curly/Plum(Cy/Pm) accumulation method. We maintained, for 40 generations under continuous exposure, each (+) chromosome as a heterozygote with (Cy) chromosome. Viability of the (+) chromosome was tested by sib-mating of (Cy/+) male and (Cy/+) female in a culture every 10th generation to obtain the homozygote. Viability indices, defined as twice the ratio of number of (+/+) flies to that of (Cy/+) flies plus 1 in the progeny of the test mating, also were calculated, which equaled 1.00 at the starting point. For the control and 0.5 and 5 mT exposed groups, percent frequencies of recessive lethal lines, defined as a line with (+/+) flies less than 0.3% in the test mating, were, respectively, 1.9, 0.9, and 2.9% (10th), 9.0, 4.9, and 9.5% (20th), 30.3, 22.9, and 30.4% (30th), and 39.9, 32.4, and 43.3% (40th generation). For the control and 0.5 and 5 mT groups, average viability indices, excluding lethals and markedly deleterious, were, respectively, 0.778, 0.796, and 0.752 (20th), 0.704, 0.698, and 0.694 (30th), and 0.669, 0.678, and 0.595 (40th generation). Their decreasing rates were 0.0054, 0.0059, and 0.0078 per generation. No significant difference was detected among the exposure levels in either the recessive lethal mutation frequency or the viability index.  相似文献   
994.
We observed six cases of patients in a dialysis programme who were apparently intoxicated by ingestion of star fruit. After ingestion of 2-3 fruits or 150-200 ml of the fruit juice, the six patients, who had previously been stable in a regular dialysis programme, developed a variety of symptoms ranging from insomnia and hiccups to agitation, mental confusion and (in one case) death. In preliminary investigations to characterize the hypothetical neurotoxin in the fruit, an extract, when injected intraperitoneally or intracerebroventricularly in rats, provoked persistent convulsions of the tonic-clonic type. It appears that star fruit (Averrhoa carambola) contains an excitatory neurotoxin. Patients with renal failure on conservative or dialysis treatment should be dissuaded from ingestion of the fruit.  相似文献   
995.
BACKGROUND: We investigated the direct effects of propylthiouracil (PTU) on corticosterone secretion both in vivo and in vitro. METHODS: Male rats were divided into 4 groups and then injected subcutaneously with saline, PTU, PTU plus thyroxine (T4), or T4 once daily for 2 weeks. After 2 weeks, rats were decapitated or received adrenocorticotropic hormone (ACTH), intravenously. Zona fasciculata-reticularis (ZFR) cells from normal, saline-, PTU-, PTU plus T4-, or T4-treated rats were incubated with ACTH, forskolin, 8-Br-cAMP, deoxycorticosterone (DOC) +/- PTU (1, 2, or 5 mg/mL) at 37 degrees C for 2 hours. Corticosterone concentrations in plasma and cell media, and 3':5'-cyclic adenosine monophosphate (cAMP) production in ZFR cells were determined by radioimmunoassay. The effects of PTU on the activities of steroidogenic enzymes in ZFR cells were measured by the amounts of intermediate steroidal products separated by thin-layer chromatography. RESULTS: The basal and ACTH-stimulated levels of plasma corticosterone in PTU-treated rats were lower as compared to saline-treated animals. Both basal and ACTH-stimulated corticosterone secretion were inhibited by PTU > 2 mg/mL in rat ZFR cells. The cAMP production induced by forskolin was lower in PTU, PTU plus T4, or T4-treated rats than in saline-treated animals. Chronic administration of PTU or PTU plus T4 inhibited the 3 beta-hydroxysteroid dehydrogenase, 21 beta-hydroxylase, and 11 beta-hydroxylase activities. Administration of PTU (1, 2, and 5 mg/mL) suppressed the basal, ACTH, 8-Br-cAMP, forskolin, and DOC-stimulated corticosterone secretion in rat ZFR cells. Likewise, PTU > 2 mg/mL inhibited the ACTH and 8-Br-cAMP-stimulated levels of intracellular cAMP in rat ZFR cells. CONCLUSIONS: These results suggest that PTU counteracts both basal and ACTH-induced adrenal steroidogenesis through their attenuation of the activity of 11 beta-hydroxylase and cAMP production in rat ZFR cells.  相似文献   
996.
AIM: Trial of the modified protocol BFM in the treatment of children with B-cell lymphomas. MATERIALS AND METHODS: 26 children with B-cell lymphoma were treated. Of them 2 children were treated according to the program for risk 2 group and 24 children were treated as risk 3 group. RESULTS: Complete remission was achieved in 23 patients. Two children were resistant. There were 2 cases of early recurrence, 1 case of early death, 1 case of death in remission. 20 patients are in complete remission. The 4-year survival is 78%. CONCLUSION: The modified protocol BFM proved to be highly effective against B-cell lymphoma in children. Its drawback is high toxicity.  相似文献   
997.
In the present study, we investigated the role of channel subunits in the membrane targeting of voltage-dependent L-type calcium channel complexes. We co-expressed the calcium channel pore-forming alpha1C subunit with different accessory beta subunits in HEK-tsA201 cells and examined the subcellular localization of the channel subunits by immunohistochemistry using confocal microscopy and whole-cell radioligand binding studies. While the pore-forming alpha1C subunit exhibited perinuclear staining when expressed alone, and several of the wild-type and mutant beta subunits also exhibited intracellular staining, co-expression of the alpha1C subunit with either the wild-type beta2a subunit, a palmitoylation-deficient beta2a(C3S/C4S) mutant or three other nonpalmitoylated beta isoforms (beta1b, beta3, and beta4 subunits) resulted in the redistribution of both the alpha1C and beta subunits into clusters along the cell surface. Furthermore, the redistribution of calcium channel complexes to the plasma membrane was observed when alpha1C was co-expressed with an N- and C-terminal truncated mutant beta2a containing only the central conserved regions. However, when the alpha1C subunit was co-expressed with an alpha1 beta interaction-deficient mutant, beta2aBID-, we did not observe formation of the channels at the plasma membrane. In addition, an Src homology 3 motif mutant of beta2a that was unable to interact with the alpha1C subunit also failed to target channel complexes to the plasma membrane. Interestingly, co-expression of the pore-forming alpha1C subunit with the largely peripheral accessory alpha2 delta subunit was ineffective in recruiting alpha1C to the plasma membrane, while co-distribution of all three subunits was observed when beta2a was co-expressed with the alpha1C and alpha2 delta subunits. Taken together, our results suggested that the signal necessary for correct plasma membrane targeting of the class C L-type calcium channel complexes is generated as a result of a functional interaction between the alpha1 and beta subunits.  相似文献   
998.
Several reports have suggested that there is an increasing incidence of infantile hypertrophic pyloric stenosis (IHPS). We examined the incidence of IHPS in a stable population in the West of Ireland over a ten year period (1981-1990). During the 10 years of the study the number of live births per year did not alter significantly. The incidence of IHPS increased significantly from 0.87/1000 live births in 1981 to 5.10/1000 in 1990 (p < 0.001, Student's test), peaking in 1989 at 6.8/1000. There was no statistical correlation between the increasing incidence and feeding habits, birth rank, family history or gender distribution. The reason(s) for this increase remain unclear.  相似文献   
999.
PURPOSE: We report the MR findings in nine patients with clinical and laboratory evidence of Kallmann syndrome (KS), a genetic disorder of olfactory and gonadal development. In patients with KS, cells that normally express luteinizing hormone-releasing hormone fail to migrate from the medial olfactory placode along the terminalis nerves into the forebrain. In addition, failed neuronal migration from the lateral olfactory placode along the olfactory fila to the forebrain results in aplasia or hypoplasia of the olfactory bulbs and tracts. Patients with KS, therefore, suffer both reproductive and olfactory dysfunction. METHODS: Nine patients with KS underwent direct coronal MR of their olfactory regions in order to assess the olfactory sulci, bulbs, and tracts. A 10th patient had MR findings of KS, although the diagnosis is not yet confirmed by laboratory tests. RESULTS: Abnormalities of the olfactory system were identified in all patients. In particular, the anterior portions of the olfactory sulci were uniformly hypoplastic. The olfactory bulbs and tracts appeared hypoplastic or aplastic in all patients in whom the bulb/tract region was satisfactorily imaged. In two (possibly three) patients, prominent soft tissue in the region of the bulbs suggests radiographic evidence of neurons that have been arrested before migration. CONCLUSIONS: Previous investigators of patients with KS used axial MR images to demonstrate hypoplasia of the olfactory sulci but offered no assessment of the olfactory bulbs. In the present study we used coronal images to show hypoplasia of both olfactory sulci and bulbs. In addition, we found what we believe to be the radiologic correlate of arrested neuronal migration in KS.  相似文献   
1000.
1. Nursing home residents have the right to be involved in decision making relative to their care, which researchers have demonstrated has a positive effect on residents. 2. The authors designed a study to explore discrepancies between residents' perceptions of choice and the amount of choice preferred and their relationship to self-care abilities and functional abilities in nursing home residents. 3. The results indicate that residents desired more choice than they felt they were given, but that this difference was not related to their perceptions of their self-care abilities. As residents' functional abilities increased, actual choice as well as desired choice increased slightly. 4. Nurses should structure the nursing home's approach to residents so that choice is maximized within the constraints of the institution.  相似文献   
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