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1.
Using a footshock elicited aggression paradigm, aggressive responses were scored in normal and in septal-lesioned adult male Wistar rats. Septal lesions were made electrolytically to include the medial and lateral septal nuclei. The lesion was confirmed by behavioral criteria (septal aggression) and post-mortem histology. The aggressive response types (threat, attack) of the septal animals were compared with their corresponding age and weight matched controls. Results showed a statistically significant increase (P = 0.05) in the number of attack responses but not the threat responses in septal animals. The modulatory role of the aggressive experience on responsiveness to positively rewarding or hedonic stimuli was assessed by quantifying the intracranial self-stimulation (SS) rates that were obtained before and after an aggression schedule. For testing the SS behavior bipolar electrodes were implanted in the ventral tegmental area--substantia nigra (VTA-SN). Results showed a decrease in SS pedal press rates in post-aggression schedule as compared to the pre-aggression period in the normal subjects. This depressing effect lasted for over a week. In septal lesioned rats the SS rates were virtually abolished even without having an aggressive schedule. These experiments revealed the effect of environment and of a brain area in provoking aggressive mood and its inhibitory consequence on responding for positive experience.  相似文献   
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B1b lymphocytes confer T cell-independent long-lasting immunity   总被引:6,自引:0,他引:6  
Many microbial pathogens employ antigenic variation as a strategy to evade the immune system, posing a challenge in vaccine development. To understand the requirements for immunity against such pathogens, we studied Borrelia hermsii, a relapsing fever bacterium. We found that mice deficient in T, follicular B, marginal zone B, or B1a lymphocytes resolved B. hersmii bacteremia and became resistant to reinfection. The resolution of bacteremia coincided with an expansion and persistence of B1b lymphocytes, and purified B1b lymphocytes from convalescent wild-type or TCR-betaxdelta-/- mice conferred immunity to Rag1-/- mice. The B1b lymphocytes in the reconstituted Rag1-/- mice provided long-lasting immunity by rapidly generating B. hermsii-specific IgM but not IgG upon bacterial challenge. Unmutated IgM is sufficient to eliminate B. hermsii, because AID-/- mice deficient in somatic hypermutation and class switch recombination efficiently resolved all bacteremic episodes. These data demonstrate that B1b lymphocytes can provide long-lasting T cell-independent IgM memory.  相似文献   
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Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis.  相似文献   
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Height-weight relationship in young healthy Indian males (19-22 yrs.) has been established. It is concluded that the relationship of the form: log w = 1.18 + 0.35 h fits well to the data on height h (in metres) and weight w (in kilograms) for this group of subjects, the logarithm is taken to the base 10. The results of the present study show that Ehrenberg's equation of the form: log w = 0.8 h + 0.4 cannot be extended beyond the age of 18 years in young healthy Indian males.  相似文献   
6.
Weaning and food supplementation practices were examined in a 12-month prospective study of 200 mother-infant pairs from a rural area of Sewagram, India. Only 2 mothers (1%) began weaning before 4 months of age. Between 4 and 6 months, 76 (38%) mothers initiated weaning; at 6 months, this rate was 61%. Illiterate women and mothers with a primary school education, multiparas, and those living in joint families were most likely to defer weaning until after 6 months. Health education campaigns focused on the importance of exclusive breast feeding for the first 4-6 months, followed by the introduction of semisolid foods, are recommended.  相似文献   
7.
Hanging is one of the most common methods of suicide in India in which death of the individual occurs instantaneously. However, a few cases have been reported in literature in which death has occurred after a certain period of time or the patient has survived after prolonged resuscitative measures. A case of a 20-year-old female is described who survived for nine days after hanging, remaining unconscious throughout in the hospital. She died due to cerebral damage caused by cerebral anoxia.  相似文献   
8.
Growth rate of non‐vestibular intracranial schwannomas A group of nine patients with non‐vestibular intracranial neuromas (four jugular, four facial, one trigeminal) underwent an interval scanning management policy, with serial annual magnetic resonance (MR) imaging. Tumour volume was assessed by manual measurement of the tumour area by MR imaging. Tumour volume was assessed by manual measurement of the tumour area on MR imaging axial cuts. The mean tumour size at presentation was 4.6 cm3 (range 0.7–17.8 cm3). During a mean follow‐up of 36 months (range 22–50 months), five out of nine tumours grew significantly at a rate of more than 5% of their initial volume per year. Only those tumours growing at a rate of more than 20% initial volume per year exhibited symptom progression. During a 36‐month period of interval scanning, just over 50% of non‐vestibular intracranial neuromas exhibited significant growth. Symptom progression was found to be a strong indicator of a high growth rate. This proportion exhibiting growth is higher than that demonstrated by unilateral sporadic vestibular schwannomas, but less than in patients with neurofibromatosis II. Early treatment of non‐vestibular intracranial neuromas should therefore be considered.  相似文献   
9.
Indian Journal of Pediatrics - To evaluate effect of one year exercise intervention program on bone mineral accrual in children and adolescent with cystic fibrosis (CF). Fifty-two CF children (mean...  相似文献   
10.
Introduction  Liver disease and the development of hepatic fibrosis are complications associated with total parenteral nutrition (TPN). Patients developing cirrhosis and portal hypertension in the setting of intestinal failure have a high mortality and may require combined liver and intestinal transplantation which carries much higher morbidity and mortality than isolated intestinal transplantation. Discussion  Recently, regression of hepatic fibrosis in patients with TPN liver disease has been described following intestinal transplantation. To date, there has been no demonstration of the reversal of established cirrhosis due to long-term TPN injury. Herein, we describe a patient with intestinal failure who developed cirrhosis from long-standing TPN injury and underwent isolated intestinal transplantation. He had no overt clinical stigmata of portal hypertension and had preserved liver function. Serial liver biopsies were reviewed and assessed with standard histology and quantitation of fibrosis using image analysis. Dramatic regression of fibrosis and reversal of cirrhosis were observed 17 months posttransplantation. Image analysis demonstrated a 14% total decrease in the percentage area of fibrosis. Conclusions  Cirrhosis related to TPN may be rapidly reversible after isolated intestinal transplantation. Such patients may be able to undergo isolated intestinal transplantation if they do not have hepatic synthetic compromise or clinical stigmata of portal hypertension.  相似文献   
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