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L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
23.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
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Aneurysm of sinus of Valsalva dissecting into interventricular septum is a rare entity. We report one such case who was incidentally diagnosed by echocardiography to have this abnormality during evaluation of a clinically suspected isolated aortic regurgitation.KEY WORDS: Aneurysm – dissecting – sinus of Valsalva, Echocardiography  相似文献   
26.
To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs  相似文献   
27.
Rapid slide culture method using human blood medium was utilized for the primary culture of Mycobacterium tuberculosis and the results obtained were compared with results of smear examination of sputum specimens from fresh cases of pulmonary tuberculosis. Smear and rapid slide culture results of a total of 320 patients were analyzed. Slide culture was positive in 104 cases whereas smears were positive in 90 cases. Early culture confirmation in 7 days coupled with positivity better than smear examination, makes rapid slide culture a better method for diagnosis.KEY WORDS: Mycobacterium tuberculosis, Rapid slide culture, Bacteriological techniques, Colony count microbial  相似文献   
28.
An epidemic of dengue haemorrhagic fever (DHF) occurred in Delhi in 1996. A total of 240 children between the age of 4 months to 13 years of either sex, admitted in one hospital, were evaluated. Two hundred and sixteen (90%) children were from Delhi. A clinical diagnosis of dengue fever (DF) was made in 25 (10%), dengue fever with unusual bleeding (DFB) in 22 (9%), DHF in 80 (33%) and dengue shock syndrome (DSS) in 113 (47%) of the children strictly according to the WHO classification. The age peaked at 8 years. There was no association between various grades of severity of illness and age-groups though girls suffered from more severe illness. No association between severity of malnutrition and severity of illness was observed. Tourniquet test was positive in 40% with DF, 18% with DFB, 62% with DHF and 64% with DSS. In DSS haematemesis was present in 55 (49%), epistaxis in 39 (35%), melaena in 27 (24%) and ecchymosis in 34 (30%) patients. Children diagnosed as DFB had haematemesis and epistaxis in 12 (55%) and 10 (45%) respectively. Intravenous fluid requirement was clearly less in DFB patients than in DHF/DSS patients. Unusual clinical features in the form of jaundice were present in 7 (6%), hepatic encephalopathy in 6 (5%) and dengue encephalopathy in 6 (5%) patients. Dengue 2 virus was isolated from 10 of the 50 patients for whom viral culture was done on C6/36 clone of Aedes albopictus cell line. Eighteen patients suffering from DSS died giving an overall case fatality of 7.5%. The mortality rate in DHF/DSS was 9.3%. It is further suggested that DFB is a distinct entity. Most patients could be classified by the WHO classification if a retrospective packed cell volume was used to assess haemoconcentration. We suggest that development of area-specific criteria for diagnosis and management is desirable.  相似文献   
29.
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   
30.
The effect of vagotomy on the post-prandial alkaline tide was assessed by measuring the fasting and postprandial urinary pH before and after vagotomy in 50 cases of chronic duodenal ulcer treated by posterior truncal vagotomy or gastrojejunostomy or pyloroplasty. Results showed that post-prandial urinary pH fell after vagotomy confirming the completeness of vagotomy. This test is safe, reliable, noninvasive and a simpler bedside procedure as compared to the conventional Hollander''s insulin test.KEY WORDS: Vagotomy, Alkaline tide  相似文献   
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