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21.
Spontaneous and mitomycin C(MMC)-induced sisyer chromatid exchanges were studied in 11 patients with retinoblastoma and 7 normal controls. Spontaneous rates were similar in patients and in controls. The MMC-induced rate was found to be significantly higher in bilaterally affected patients than in controls. It is suggested that this increase may be due to a DNA repair deficiency. However, it is not possible to clarify wether this abnormality is associated with the retinoblastoma gene or with another factor acting on the degree of expressivity of the disease in gene carriers.  相似文献   
22.
Long-Evans hooded rats were tested for emotionality and observed by pairs in an open field for 6 consecutive days. Postoperative observations indicated that both emotionality and social cohesiveness were dramatically altered by ventromedial and anterolateral hypothalamic lesions. Tegmental, interpeduncular and habenular lesions were shown to have no effect on these behaviors. Alterations in behavior observed following hypothalamic ablations were related to septal and amygdaloid effects, and the possibility of separate projection systems for emotionality and social cohesiveness was discussed.  相似文献   
23.
Eighty-nine patients with leprosy, 65 classified as lepromatous and 24 as tuberculoid, were examined in this study. Skin test responses to protein antigens and dinitrochlorobenzene (DNCB) were depressed in lepromatous patients compared to controls. Tuberculoid patients did not exhibit a significant depression to microbial antigens, but they showed a definite depression in the ability to be sensitized with DNCB. The transfer of delayed hypersensitivity reactions to tuberculin, trichophytin, and lepromin (Fernandez and Mitsuda reactions) was accomplished in lepromatous and indeterminate leprosy patients using viable lymphocytes from donors presenting positive reactions to these antigens. The lepromin reaction was also transferred to patients with South American blastomycosis and cutaneous leishmaniasis. The positive reactions of adoptive immunity were confirmed by histologic examination of skin biopsies.  相似文献   
24.
R F Ramig 《Virology》1983,127(1):91-99
A number of factors that affect genetic interaction during mixed infection with temperature-sensitive mutants of simian rotavirus SA11 have been examined. (1) Statistical analyses of recombination frequency (RF) indicated that (a) the variability noted in RF was not related to variations in experimental conditions and (b) a linear map of the mutations could not be drawn. (2) The wild phenotype of recombinant progeny was stable on passage. (3) Aggregates of progeny virus or heterozygous progeny virus particles did not contribute significantly to the observed RF. (4) RF increased in parallel with multiplicity of infection. (5) A maximal, or near maximal, RF was obtained at the earliest time significant recombinants could be detected. (6) Recombination was efficient at nonpermissive temperature. (7) Complementation did not occur or was inefficient. (8) Mutants from all recombination groups interfered with the growth of wild-type virus at both permissive and nonpermissive temperatures.  相似文献   
25.

Introduction

The care activity of internal resident doctors is common to practically all medical and surgical training programs; however, there are no national data available regarding the situation of this activity from the perspective of the resident. The present study has sought to collect the opinion of the resident internal physicians on the health care performance and the teaching character that links them to their corresponding emergency departments, in the following areas: overall training value, appreciation of the workload, characteristics of the morning rotation, supervision or tutoring, etc.

Method

The study was performed using a questionnaire that was distributed at the national level through the network of representatives of the SEMES-MIR group of the Spanish Society of Emergency and Emergency Medicine.

Results

A total of 1083 questionnaires were collected from 38 hospitals, corresponding to a response rate of 28%. The most significant educational contribution was the general knowledge about emergency medical care and the interpretation of complementary tests, while the less significant were aspects related to pharmacoeconomics, sustainability and cost-benefit of medical and non-medical processes related to medicine Emergency. As for the burden of care during a day of continuous care, the first year residents saw a mean of 12.3 patients) (SD 2.2), the second and third year 18.1 (SD 2.2), and the older residents 14.5 (SD 2.4). Less than half (44%) of the respondents identified their supervision model as «direct», while 37.2% identified it as «semi-pyramidal». A minority (14.2%) of respondents acknowledged having been encouraged to undertake scientific activities related to emergency medicine.

Conclusions

The results of this questionnaire should serve as a basis for the future planning of new models of teaching and care for residents and emergency services, as well as to stratify the priorities of attention to the relationship between emergency services and resident physicians.  相似文献   
26.
27.
Summary Distal deletion of chromosome 1q has been reported in nearly 30 patients, all being associated with a deletion ranging from the 1q42 or q43 band to 1qter region. Here, we describe a girl with 1q terminal deletion resulting from an unbalancedde novo translocation t(1;D or G)(q44; p11), as revealed by the presence of a satellited feature and an NOR-stained region at the tip of 1q. We suggest that most of the phenotypic abnormalities seen in patients with 1q distal deletion are attributable to the monosomy for band 1q44.  相似文献   
28.
A 3.5-month-old female infant manifesting dysmorphic facies, developmental delay and failure to thrive was referred for cytogenetic evaluation. Peripheral lymphocytes revealed three chromosomally distinct cell lines: 46,XX/46,XX,10p+/47,XX,10p+,+mar. Dermal fibroblasts revealed only the 46,XX,10p+cell line. High resolution G-, R-, and Q-banding suggested that the extra chromosomal material (10p+) represented a duplication of the segment 13q14----13qter. Parental karyotypes were normal. As absolute identification of de novo chromosomal abnormalities, based solely on cytogenetic studies, is sometimes difficult, both biochemical and molecular approaches were undertaken to elucidate this abnormality in more detail. Dosage effects were examined using esterase D (localized to 13q14.1) and the DNA probes p1E8 and p9A7 (localized to 13q22 and 13q31/32, respectively). These studies suggested the presence of only 2 copies of esterase D, but 3 copies of both DNA probes, allowing identification of the breakpoint at 13q14.2.  相似文献   
29.
The distribution of HLA antigen frequencies has been studied in patients with affective disorders. There were no significant differences between bipolar patients, unipolar patients, or controls. Preliminary data on HLA antigen distribution in schizophrenic patients are reported. Our negative results in affective disorders are discussed in relation to HLA studies reported from other laboratories, with special reference to some potential methodological problems.  相似文献   
30.
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