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K. B. Shapovalova S. P. Poltavets M. I. Boiko 《Neuroscience and behavioral physiology》1985,15(3):254-264
A model of instrumental defensive reflexes associated with the maintenance of a specific posture was used in chronic experiments with four dogs to demonstrate the preferential inhibitory influence of preliminary low-frequency stimulation (2 impulses/sec) of the head of the caudate nucleus in the right and left hemispheres on the electromyographic and mechanographic components of the instrumental defensive reflex effecting the reflex motor program. Subjected to the greatest changes were the postural, components of the electromyogram, which permits the postulate as to the importance of the caudate head in the organization of posture. It was shown that the caudate head is bilaterally involved in the prerelease processes preceeding the instrumental response. At the same time, the difficulty of inhibiting the performance of the actual instrumental task- the avoidance of an electric current- was noted during stimulation of the caudate head in a system of instrumental defensive reflexes.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 68, No. 11, pp. 1488–1499, November, 1982. 相似文献
4.
Donor insemination: child development and family functioning in lesbian mother families 总被引:1,自引:5,他引:1
Brewaeys A; Ponjaert I; Van Hall EV; Golombok S 《Human reproduction (Oxford, England)》1997,12(6):1349-1359
Findings are presented of a comparative study investigating the family
relationships and the emotional and gender development of children raised
in lesbian mother families. A total of 30 lesbian mother families with 4-8
year old children created as a result of donor insemination (DI) were
compared with 38 heterosexual families with a DI child and with 30
heterosexual families who had a naturally conceived child. A variety of
assessment measures, including a standardized interview and questionnaires
from the parents and psychological testing of the child were used to
collect the data. The quality of the couples' relationships and the quality
of the mother-child interaction did not differ between lesbian mother
families and either of the heterosexual family groups. The quality of the
interaction between the social mother and the child in lesbian families was
superior to that between the father and the child in both groups of
heterosexual families. Childrens' own perception of their parents was
similar in all family types; the social mother in lesbian families was
regarded by the child to be as much a 'parent' as the father in both types
of heterosexual families. With regard to their emotional/behavioural
development, boys and girls raised in lesbian mother families were well
adjusted and their gender role development did not differ from that of
children raised in heterosexual families. These results indicate that child
and family development in lesbian mother families is similar to that of
heterosexual families.
相似文献
5.
Donor insemination: Dutch parents' opinions about confidentiality and donor anonymity and the emotional adjustment of their children 总被引:1,自引:4,他引:1
Brewaeys A; Golombok S; Naaktgeboren N; de Bruyn JK; van Hall EV 《Human reproduction (Oxford, England)》1997,12(7):1591-1597
Results from a comparative study investigating 38 donor insemination (DI)
Dutch families with 4-8 year old children are presented. The aims of this
study were to investigate parents' opinions on the issues of
confidentiality and donor anonymity, to assess the emotional development of
the children, and to examine in DI families the association between secrecy
with regard to the use of a donor and the emotional adjustment of the
children. The DI families were compared to families with a child conceived
by in-vitro fertilization (IVF) and to families with a naturally conceived
child. Secrecy appeared to be associated with DI and not with IVF: 74% of
the DI parents intended not to inform the child about the way in which
she/he was conceived, whereas none of the IVF parents intended to keep the
secret. Only one set of DI parents and two sets of IVF parents had actually
told the child. As to donor anonymity, a spread of opinions appeared among
DI parents; 57% preferred an anonymous donor, 31% would have liked non-
identifying information about the donor, 9% preferred the donor's identity
to be registered and 3% remained unsure. Parents' major concern was to know
more about the medical/genetic background of the donor. Mothers and fathers
in the DI families differed in their opinions concerning the issues of
confidentiality and donor anonymity: fathers, more often than mothers, were
secretive with regard to the use of a donor and husbands, more often than
their wives, were in favour of donor anonymity. With regard to the
emotional development of the children, more emotional/behavioural problems
were revealed among DI children than among children who were naturally
conceived. No association was found between secrecy and the
emotional/behavioural adjustment of the children.
相似文献
6.
Light scattering from cervical cells throughout neoplastic progression: influence of nuclear morphology,DNA content,and chromatin texture 总被引:1,自引:0,他引:1
Drezek R Guillaud M Collier T Boiko I Malpica A Macaulay C Follen M Richards-Kortum R 《Journal of biomedical optics》2003,8(1):7-16
A number of noninvasive fiber optic optical technologies are under development for real-time diagnosis of neoplasia. We investigate how the light scattering properties of cervical cells are affected by changes in nuclear morphology, DNA content, and chromatin texture, which occur during neoplastic progression. We used a Cyto-Savant computer-assisted image analysis system to acquire quantitative nuclear features measurements from 122 Feulgen-thionin-stained histopathologic sections of cervical tissue. A subset of the measured nuclear features was incorporated into a finite-difference time-domain (FDTD) model of cellular light scattering. The magnitude and angular distribution of scattered light was calculated for cervical cells as a function of pathologic grade. The nuclear atypia strongly affected light scattering properties. The increased size and elevated DNA content of nuclei in high-grade lesions caused the most significant changes in scattering intensity. The spatial dimensions of chromatin texture features and the amplitude of refractive index fluctuations within the nucleus impacted both the angular distribution of scattering angles and the total amount of scattered light. Cellular scattering is sensitive to changes in nuclear morphology that accompany neoplastic progression. Understanding the quantitative relationships between nuclear features and scattering properties will aid in the development of noninvasive optical technologies for detection of precancerous conditions. 相似文献
7.
Prolonged clinico-immunological observation of 85 patients with definite multiple sclerosis (MS) was performed in order to elucidate the connections between the clinical and immune state. A battery of immunological investigations was performed, including estimation of T-cell subpopulations in blood and cerebrospinal fluid (CSF); proliferative responses of circulating lymphocytes to mitogens, recombinant interleukin-2 (rIL2) and myelin basic protein levels in different culture conditions; levels of immunoglobulin (Ig) in sera and CSF, and of Ig production in vitro; indices of IL2 synthesis and IL2 sensitivity; production of prostaglandin E2 and tumour necrosis factor (TNF) alpha by monocytes and levels of -endorphin in sera and supernatants phytohaemagglutinin of (PHA)-activated cells. Clinical observation was performed periodically using Kurtzke scales and was supplemented by repeated recording of evoked potentials and magnetic resonance imaging. Initial investigations showed specific differences between patients with MS and the control groups (donors and patients with other neurological disorders of the same age). Correlative and regressive analyses showed no association between immunological and clinical parameters at the initial investigation, although immunological indexes were inter-related, and indicated specific alterations in immuno-regulation in MS. Retrospective analysis revealed associations between the clinical status of patients with MS and their previous immune status. Evidence of cell activation — including a decreased percentage of circulating cells with differential antigens, lower cell mitogen-induced proliferative responses in vitro, with restoration following the addition of autoserum, greater IL2 sensitivity, and increased TNF-alpha production by macrophages — often predicted the clinical manifestation of deterioration. It is proposed that the immunopathological process in MS has a number of stages with characteristic features, and that progression from one stage to another can be subclinical. No single immunological index can be used to determine stage. Only systemic alterations reflect the real situation, whilst every patient has some abnormalities. A system of clinico-immunological monitoring could severe as the basis for a new approach to the dynamic treatment of MS. 相似文献
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Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
Methodology:
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Results:
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Conclusion:
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
10.
DR Brewster MJ Manary IS Menzies EV O'Loughlin RL Henry 《Archives of disease in childhood》1997,76(3):236-241
Intestinal permeability can be assessed non-invasively using the lactulose-rhamnose (L-R) test, which is a reliable measure of small intestinal integrity. AIMS: To determine risk factors for abnormal intestinal permeability in kwashiorkor, and to measure changes in L-R ratios with inpatient rehabilitation. DESIGN: A case-control study of 149 kwashiorkor cases and 45 hospital controls. The L-R test was adapted to study kwashiorkor in Malawi, with testing at weekly intervals during nutritional rehabilitation. Urine sugars were measured by thin layer chromatography in London. RESULTS: The initial geometric mean L-R ratios (x100) (with 95% confidence interval) in kwashiorkor were 17.3 (15.0 to 19.8) compared with 7.0 (5.6 to 8.7) for controls. Normal ratios are < 5, so the high ratios in controls indicate tropical enteropathy syndrome. Abnormal permeability in kwashiorkor was associated with death, oliguria, sepsis, diarrhoea, wasting and young age. Diarrhoea and death were associated with both decreased L-rhamnose absorption (diminished absorptive surface area) and increased lactulose permeation (impaired barrier function) whereas nutritional wasting affected only L-rhamnose absorption. Despite, clinical recovery, mean L-R ratios improved little on treatment, with mean weekly ratios of 16.3 (14.0 to 19.0), 13.3 (11.1 to 15.9) and 14.4 (11.0 to 18.8). CONCLUSION: Abnormal intestinal permeability in kwashiorkor correlates with disease severity, and improves only slowly with nutritional rehabilitation. 相似文献