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961.
962.
Monoclonal antibodies which recognize antigenic determinants expressed by T-cells and Ig-bearing cells, respectively, allowed lymphocyte subpopulations involved in allograft rejection of muscle transplants to be identified in the teleost fish Dicentrarchus labrax (L.). The monoclonal antibody DLT15 first allowed recognizing T-cells involved in an in vivo antigen-driven cellular response in teleosts. Immunohistochemical studies showed a high density of lymphocytes in allografts and provided evidence of predominance of T-cells. The heterogeneity of the cell populations recognized by the antibodies was evidenced by the different size, cytology, and staining patterns of T-cells and Ig-bearing cells. 相似文献
963.
Rates of synonymous and nonsynonymous nucleotide substitutions and codon usage bias (ENC) were estimated for a number of nuclear and chloroplast genes in a sample of centric and pennate diatoms. The results suggest that DNA evolution has taken place, on an average, at a slower rate in the chloroplast genes than in the nuclear genes: a rate variation pattern similar to that observed in land plants. Synonymous substitution rates in the chloroplast genes show a negative association with the degree of codon usage bias, suggesting that genes with a higher degree of codon usage bias have evolved at a slower rate. While this relationship has been shown in both prokaryotes and multicellular eukaryotes, it has not been demonstrated before in diatoms. 相似文献
964.
965.
OBJECTIVE: A set of guidelines to assist men with traumatic brain injury (TBI) to alleviate gender role strain was assessed to determine its effectiveness and acceptability to participants. METHOD: Four adult male participants with TBI received the intervention (the set of guidelines) for 4 months. The intervention consisted of rebuilding self-identified gendered social roles and activities. Focused interviews and participant observation were used to determine whether gender role strain changed after intervention. RESULTS: The participants reported that the intervention enabled them to (a) enhance their gender role satisfaction through newly rebuilt roles and activities, (b) attain certain long-held personal goals, (c) feel more like members of society, (d) perceive a greater congruency between their internal self-images and external postinjury roles, (e) learn more about personal skills and values as men, (f) feel more comfortable using help-seeking behaviors, (g) feel a sense of shared experience and affinity, (h) feel more understood and accepted, and (i) contribute to others through community member roles. DISCUSSION: The set of guidelines for alleviating gender role strain was effective in assisting these participants to enhance their gender role satisfaction through rebuilding desired male-gendered social roles and activities. Dating, courtship, extended family member, community member, friend, and mentor-protege roles, lost as a result of TBI, were rebuilt through gender-neutral activities that facilitated a sense of volitional control, competency, and normalcy. Nonetheless, the men continued to lack desired rites of passage leading from male adolescence to adulthood. 相似文献
966.
BACKGROUND AND PURPOSE: Stroke-induced hemiparesis involving the arm and hand results in regular, repeated overuse of the opposite hand and wrist. Because repetitive hand and wrist movement is a common cause of carpal tunnel syndrome (CTS), we examined the nonparetic upper limb in stroke patients for evidence of CTS. METHODS: We measured bilaterally sensory nerve conduction velocity (SNCV), motor nerve conduction velocity (MNCV), sensory nerve action potentials (SNAP) at the wrist, palm-to-wrist distal sensory latency (DSL), palm-to-wrist SNAP, compound motor action potentials (CMAP), and distal motor latency (DML) in stroke patients and control subjects. Controls were right-handed, >/=65 years old, lucid, independent in their activities of daily living, and had no disease known to cause CTS. Stroke patients were divided into a functioning hand group (n=61) and a disused hand group (n=71). All patients had hemiplegia. RESULTS: Tinel's sign was observed on the nonparetic side in 57.7% of patients with a disused hand and in 31.1% of those with a functioning hand. All electrophysiological indices were significantly more abnormal on the nonparetic side than on the hemiparetic side or in controls. Patients with a disused hand showed greater abnormality on the nonparetic side in SNCV, SNAP, palm-to-wrist DSL, DML, and CMAP than patients with a functioning hand. CONCLUSIONS: Overuse of the nonparetic hand and wrist of the nonparetic side may result in CTS in stroke patients, especially when the paretic hand is not functional. Wrist splinting or other prophylactic treatments beginning soon after stroke might help to prevent CTS. 相似文献
967.
Familial acromegaly/gigantism occurring in the absence of multiple endocrine neoplasia type I (MEN-1) or the Carney complex has been reported in 18 families since the biochemical diagnosis of GH excess became available, and the genetic defect is unknown. In the present study we examined 2 unrelated families with isolated acromegaly/gigantism. In family A, 3 of 4 siblings were affected, with ages at diagnosis of 19, 21, and 23 yr. In family B, 5 of 13 siblings exhibited the phenotype and were diagnosed at 13, 15, 17, 17, and 24 yr of age. All 8 affected patients had elevated basal GH levels associated with high insulin-like growth factor I levels and/or nonsuppressible serum GH levels during an oral glucose tolerance test. GHRH levels were normal in affected members of family A. An invasive macroadenoma was found in 6 subjects, and a microadenoma was found in 1 subject from family B. The sequence of the GHRH receptor complementary DNA in 1 tumor from family A was normal. There was no history of consanguinity in either family, and the past medical history and laboratory results excluded MEN-1 and the Carney complex in all affected and unaffected screened subjects. Five of 8 subjects have undergone pituitary surgery to date, and paraffin-embedded pituitary blocks were available for analysis. Loss of heterozygosity on chromosome 11q13 was studied by comparing microsatellite polymorphisms of leukocyte and tumor DNA using PYGM (centromeric) and D11S527 (telomeric), markers closely linked to the MEN-1 tumor suppressor gene. All tumors exhibited a loss of heterozygosity at both markers. Sequencing of the MEN-1 gene revealed no germline mutations in either family, nor was a somatic mutation found in tumor DNA from one subject in family A. The integrity of the MEN-1 gene in this subject was further supported by demonstration of the presence of MEN-1 messenger ribonucleic acid, as assessed by RT-PCR. These data indicate that loss of heterozygosity in these affected family members appears independent of MEN-1 gene changes and suggest that a novel (tissue-specific?) tumor suppressor gene(s) linked to the PYGM marker and expressed in the pituitary is essential for regulation of somatotrope proliferation. 相似文献
968.
OBJECTIVE: To study the effects of thevetoside (TS), a cardiac glycoside, and an inhibitor of Na+, K(+)-ATPase, on tumor cells cultured in vitro. METHODS: The cytotoxic effects of TS on tumor cells were determined by trypan blue dye exclusion, neutral red vital staining and clonogenic assay. The time-effect relationship and growth inhibition of tumor cells by TS were assayed with trypan blue exclusion method. RESULTS: TS at low doses (0.005-0.1 mg.L-1), with dose dependence, was able to kill SMMC-7721, SGC-7901 and HeLa cells. IC50 values for SMMC-7721, SGC-7901 and HeLa cells were 0.007, 0.011 and 0.018 mg.L-1 by trypan blue dye exclusion test and 0.016, 0.055 and 0.078 mg.L-1 by neutral red vital staining test. TS inhibited the clonal forming rate of SMMC-7721 and SGC-7901 significantly with IC50 values of 0.021 and 0.036 mg.L-1, respectively. Only when the cells were continuously treated with TS for more than 8 hours, the drug-induced cell lethality could be displayed and strengthened quickly. The growth of tumor cells was notably inhibited after they were exposed to 0.1 microgram/ml of TS for 12 hours. All the experimental results of antitumor activity in vitro showed that SMMC-7721 was most sensitive to TS among the three kinds of tumor cells. CONCLUSIONS: TS has cytotoxic action on tumor cells cultured in vitro and this lethal effect must have an action process, in which tumor cells are not dead but suffer from deadly injury and lost the capability of unlimited proliferation. 相似文献
969.
Detection and resolution of square patches of sinusoidal gratings were measured in central and peripheral vision (30 degrees horizontal temporal visual field) for high-contrast gratings as a function of the number of cycles in the stimulus. We determined performance in a forced-choice paradigm for a fixed number of stimulus cycles by arranging for stimulus diameter to vary inversely with spatial frequency. For both psychophysical tasks and for both target locations, the psychometric function relating performance to log spatial frequency shifted to higher frequencies without changing slope significantly as the number of cycles in the stimulus was increased. Thus the entire effect could be captured by an analysis of spatial acuity, which increased with increasing number of grating cycles over the range 0.5-6 cycles but remained constant over the range 6-14 cycles. In the central field, resolution acuity and detection acuity were equal regardless of the number of cycles in the stimulus. In the peripheral field, detection acuity exceeded resolution acuity and perceptual aliasing occurred for stimuli in the range 1-14 cycles. From this result we conclude that resolution acuity is sampling limited in the periphery, provided that the stimulus contains at least one full cycle of the grating. Essential features of the results could be accounted for by Fourier analysis of the stimulus. 相似文献
970.