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91.
Transplantation has come of age as an important investigative tool for studying normal growth and development of the brain tissue. The present study reports the effect of lateral hypothalamic (LHA) lesion and foetal hypothalamic tissue transplantation on the feeding behaviour. In a group of rats, LHA was lesioned bilaterally by passing direct current. Subsequently, in a separate group of rats, foetal hypothalamic tissue was transplanted at the lesioned site. Following LHA lesion, all the rats died of aphagia and adipsia within 7 days, whereas, the rats in whom foetal hypothalamus was transplanted, started taking food and water in small quantities from the first day of transplantation itself. Later, they were able to attain their preoperative values. This recovery of the feeding behaviour following foetal tissue transplantation may be due to the formation of synaptic connections or due to the release of neurotrophic factors. 相似文献
92.
93.
Seasonal affective symptoms in adults with residual attention-deficit hyperactivity disorder. 总被引:1,自引:0,他引:1
There is evidence from clinical, epidemiological, and neuroimaging studies that attention-deficit hyperactivity disorder (ADHD) and seasonal affective disorder (SAD) may have several features in common. To assess seasonal affective symptoms in adults with ADHD, 115 individuals attending an adult ADHD clinic in Toronto, Ontario, Canada were asked to complete the Seasonal Pattern Assessment Questionnaire (SPAQ). From this clinic population of 115, a total of 56 completed SPAQs were returned. Assuming that all individuals failing to complete the SPAQ were nonseasonal and depending on which case-finding criteria were used, the rate of SAD in the overall clinic sample was estimated at either 10.4% (Terman criteria) or 19.1% (criteria of Kasper et al.). These prevalence rates are significantly greater than the rates reported in large population surveys at similar latitudes. There was an apparent relationship between female gender, impulsive-subtype ADHD, and seasonality. Future studies to examine whether core symptoms of ADHD fluctuate across the seasons and to assess the efficacy of light therapy in "seasonal" ADHD patients would be of great theoretical and clinical interest. 相似文献
94.
Epidemiological data on most cancer sites suggest that consumption of plant foods, which contain high levels of antioxidants, might slow or prevent the appearance of cancer. We used data from three case-control studies to test this hypothesis. The total study population consisted of 617 incident cases of prostate cancer and 636 population controls from Ontario, Quebec, and British Columbia. Dietary information was collected by an in-person interview with a detailed quantitative dietary history. Unconditional logistic regression analyses were performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs). A decreasing, statistically significant association was found with increasing intakes of green vegetables (OR = 0.54, 95% CI = 0.40-0.71 for 4th quartile), tomatoes (OR = 0.64, 95% CI = 0.45-0.91), beans/lentils/nuts (OR = 0.69, 95% CI = 0.53-0.91), and cruciferous vegetables (OR = 0.69, 95% CI = 0.52-0.91 for 3rd quartile). Higher intakes of fruit were associated with higher ORs (OR = 1.51, 95% CI = 1.14-2.01 for 4th quartile), an effect that was seen for total fruit and citrus fruit, as well as for all other noncitrus fruits. Among the grains, refined-grain bread intake was associated with a decrease in risk (OR = 0.65 for 4th quartile), whereas whole-grain breakfast cereals were associated with a higher risk for prostate cancer. Of all the antioxidant nutrients studied, the ORs were higher with higher intakes of cryptoxanthin (OR = 1.44, 95% CI = 1.09-1.89 for 4th quartile). Exposure to certain dietary components of plant origin, which are potentially modifiable, indicates the theoretical scope for reducing the risk from prostate cancer. Future experimental studies or trials are warranted for further understanding. 相似文献
95.
Oral administration of aqueous extract of seeds of Cassia fistula to mated female rats from day 1-5 of pregnancy at the doses of 100 and 200 mg/kg body weight resulted in 57.14% and 71.43% prevention of pregnancy, respectively, whereas 100% pregnancy inhibition was noted at 500 mg/kg bw. In the uterine bioassay test carried out in immature bilaterally ovariectomized female rats, aqueous extract of seeds of Cassia fistula (100 mg/kg bw) increased the uterine wet weight (p<0.05) and luminal epithelial cell height (p<0.001) but did not induce premature opening of the vagina. This suggests a mild estrogenic activity of the extract. However, when the extract was administered conjointly with estradiol valerate (EDV, 0.1 mg/kg bw), it significantly (p<0.001) prevented the estrogen-induced uterotrophic effect, thus showing an antiestrogenic nature of the extract in the presence of a strong estrogen. 相似文献
96.
PURPOSE: In vitro study of the enzymes involved in aerobic, anaerobic and hexose monophosphate shunt in ultraviolet radiation exposed mice lenses. METHOD: Of the selected enzymes, lactic dehydrogenase (LDH) was representative of anaerobic glucose oxidation, succinic dehydrogenase (SDH) of the aerobic oxidation, and Glucose-6-phosphate dehydrogenase (G-6-PDH) of the Hexose Monophosphate (HMP) shunt. Other enzymes studied were ATPase and glutathione reductase (GR). RESULTS: Experiments with mice lenses in vitro showed that transparent lens became opaque following UV-irradiation at 360 nm. Opacification of the lens was accompanied by a change in enzyme activities for energy metabolism. CONCLUSION: These changes were progressive in a manner analogous to sequential morphological changes, which would be crucial in maintaining lens transparency. 相似文献
97.
98.
99.
From a Pediatric Rheumatology Clinic 361 children diagnosed as juvenile rheumatoid arthritis (JRA) according to American Rheumatism
Association-JRA criteria were studied retrospectively for their clinico-immunological profile. The mean age of onset in systemic,
pauciarticular and polyarticular onset, JRA subtypes were 5.2, 6.8 and 7.2 years respectively. There was male preponderance
in systemic and pauciarticular JRA. In seropositive polyarticular JRA, girls outnumbered boys. The frequency of occurence
of systemic, pauciarticular and polyarticular disease was 87 (24%), 108 (30%) and 166 (46%) respectively. The systemic onset
disease was dominated by extra-articular manifestations in terms of fever (100%), rash (57%), hepatomegaly (51%) and lymphadenopathy
(25%). The pauci- and polyarticular illnesses were commonly dominated by joint involvement, morning stiffness, and in few
patients, by extra-articular manifestations also. The joints were involved symmetrically. Most commonly involved joints in
order of decreasing frequency were knee, ankle, wrist and elbow in all the subtypes. Anemia and leucocytosis were observed
in majority with higher frequency in systemic onset JRA. The rheumatoid factor (RF) was present in 15% of polyarticular JRA.
RF was also present in 7 and 9% of patients with pauciarticular and systemic subtypes respectively. The antinuclear antibody
was positive in only 3 out of 66 patients in whom the test was carried out.
The demographic profile and trends in clinical features were similar to the studies reported on caucasian population with
difference in the actual frequency of various clinical features. 相似文献
100.
Dhar S Jain S Verma G Tanwar RK 《Indian journal of dermatology, venereology and leprology》1996,62(5):331-332
A case of disseminated molluscum contagiosum (MC) has been reported in a patient suffering from AIDS. Most of the lesions were erythematous papules and nodules with central unbilication. A few giant lesions and lesions over genitalia were also observed. 相似文献