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941.
BACKGROUND--Progressive pulmonary vascular disease in surgically unrepaired transposition of the great arteries with or without ventricular septal defect had been frequently described in the past. Occurrence of progressive pulmonary vascular disease has been reported even after atrial switch procedure done at three months of age. With the advent of neonatal surgical repair, this problem is virtually non-existent. There is a small subgroup of infants with transposition of the great arteries who show pulmonary vascular disease in the neonatal period that can adversely affect the surgical outcome. The clinico-pathological correlation in this group of patients was studied. OBSERVATIONS--Three patients, with transposition of the great arteries and intact ventricular septum, who showed histological evidence of pulmonary vascular disease in the neonatal period or early infancy are described. Two of these patients, continued to have poor systemic oxygenation despite adequate atrial communication. One patient had a close ductus arteriosus within the first two hours of birth while on prostaglandin E1 infusion. CONCLUSIONS--In the absence of left ventricular outflow tract obstruction, a poor response to atrial septostomy suggests pulmonary hypertension and pulmonary vascular disease. Antenatal constriction of the ductus arteriosus may contribute to such changes in pulmonary vasculature.  相似文献   
942.
An improved bioassay for calcitonin   总被引:2,自引:0,他引:2  
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943.
Kumar PJ 《Gut》2003,52(2):168-169
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944.
In the Indian state of Bihar, the sensitivities and specificities of direct agglutination tests (DAT) and rK39 test strips for the detection of Leishmania donovani infection in humans were explored and found to be generally good (92%-100%). When 172 asymptomatic individuals [16 'case-contacts' who lived in the same households as past or current, confirmed cases of visceral leishmaniasis (VL) and 156 other subjects from neighbouring households] were tested, the same 36 (21%) individuals, including all 16 'case-contacts', were found seropositive using each type of test. When followed-up after 3 months, 18 of the individuals who had been found seropositive in the baseline survey remained seropositive, and eight (44%) of these had developed symptomatic VL, with amastigotes in their splenic aspirates. Seven (44%) of the 16 'case-contacts' but only one (5%) of the other 20 subjects found seropositive at baseline went on to develop VL within 3 months. Although the strip test appeared slightly better than DAT for predicting the development of VL in the 172 subjects, either type of test may be very useful for the early detection of asymptomatic L. donovani infection and thus the identification of those at relatively high risk of developing VL.  相似文献   
945.

Purpose

Visceral leishmaniasis (VL), a protozoan disease, is 100 % fatal if left untreated. Anemia is common in VL which plays a role in expression of clinically overt VL disease. Laboratory clues are scarce for strengthening clinical suspicion for severity in VL. Hypertriglyceridemia has emerged as a new concept for the diagnosis and prognosis in VL. The present study is aimed at correlating the magnitude of hypertriglyceridemia with the severity in VL.

Materials and methods

A retrospective case–control study was conducted between January 2012 to December 2013 among 124 patients coming for treatment from VL endemic areas, who had fever of more than 15 days and did not respond to antimalarials and antibiotics. The parasitologically confirmed VL cases (n = 87) were categorized as mild/moderate (n = 60) and severe (n = 27) groups according to WHO classification for anemia and parasite burden. Serum triglycerides were assayed in VL groups along with controls (n = 37).

Results

Serum triglyceride level was significantly higher in VL than controls [mean values were 173.50 ± 47.67 versus 127.1 ± 53.79 mg/dl, respectively (p < 0.0001)]. Triglyceride level was significantly higher in severe than in mild/moderate group of VL [211.3 ± 50.2 mg/dl versus 134 ± 45.09 mg/dl, respectively (p < 0.0001)]. Hypertriglyceridemia (>161.7 mg/dl) was noted in all severe VL patients, compared to 31.66 % of mild or moderate group (p < 0.0001). There was no significant difference between mild/moderate VL and controls.

Conclusions

It is hypothesized that hypertriglyceridemia could be of additional diagnostic benefit to assess the probability and severity of VL in endemic areas.
  相似文献   
946.
We examined the "vascular waterfall" hypothesis, which proposes that coronary flow is unaffected by elevations in outflow pressure until the latter reaches a critical threshold level, in 29 isolated canine hearts. In fibrillating hearts vasodilated with adenosine or carbocromen, coronary flow and the coronary pressure-flow relation were not affected by changes in great cardiac vein pressure (PGCV) below a threshold value of 11 +/- 0.9 (mean +/- SEM) mm Hg. Further elevations of PGCV reduced flow and shifted the pressure-flow relation to the right, increasing its pressure-axis intercept (Pf=0). When vasomotor tone was augmented with vasopressin, threshold PGCV increased to 25 +/- 2.7 mm Hg (p less than 0.001). Once again, the pressure-flow relation was unaffected by changes in PGCV below the threshold value and shifted to the right when this value was exceeded. The amount by which spontaneous values of Pf=0 exceeded threshold values of PGCV was greater when vasomotor tone was augmented than during vasodilation. Pf=0 continued to exceed PGCV when the latter was raised above the threshold level. Both Pf=0 and threshold values of PGCV were less during a long diastole than during ventricular fibrillation. We reached the following conclusions. 1) During changes in PGCV below a threshold value, the coronary circulation exhibits traditional waterfall behavior. 2) The threshold pressure for altering waterfall behavior is affected by vascular tone and mechanical activity. 3) Pf=0 remains above PGCV when the latter is increased above the threshold value needed to alter flow.  相似文献   
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950.
BACKGROUND: An attempt was made to induce aortoarteritis in mice by using various antigens. METHODS AND RESULTS: The Swiss mice were immunized with eight different antigens and were grouped A to G. Group H served as control. The mice were then bled at 1st, 2nd, 4th, 6th and 8th month interval post-immunization for estimating antibody titer. Then the mice were sacrificed and the heart, aorta and kidney were taken out and processed for hematoxylin-eosin staining. There was gradual increase in the antibody titer from 1st month till 4th month within all the experimental groups (A-G), when compared with control group H. The titer started falling sharply from 6th month post-immunization. However, the control group H did not show much variation. When each individual group was compared separately with control group H, the significant statistical value was obtained. Histopathological examination revealed mild inflammation (+) in kidney by 2nd month, moderate inflammation (++) by 6th month, extensive inflammation (+++) by 8th month and alteration in the normal parenchyma of kidney by 8th month. CONCLUSIONS: The histopathological changes brought out through antigens were more pronounced by 8th month following injection of tunica media, tunica adventitia, tunica intima and aorta collagen as compared to that of standard collagen and mouse aorta injections.  相似文献   
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