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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
The lymph flow of the thoracic duct, the protein content of the lymph, bile flow and bile composition are studied during the first three hours of the recirculation phase in experimental liver transplantation. It is established that the lymph flow and the protein content of the thoracic duct decrease as a result of the interruption of hepatic lymph flow of a high protein concentration. The change in bile composition and flow is due to the reduced bile acid excretion of the transplanted hepatic tissue. 相似文献
993.
N Prasad E Lotzová J I Thornby J E Madewell J J Ford S C Bushong 《AJR. American journal of roentgenology》1987,148(2):415-417
To determine the effect of MR imaging on the immune system, 21 male C57BL/6 X DBA/2 F1 mice were exposed to MR imaging at a field strength of 0.15 T for 2 hr. Another nine mice (controls) were sham exposed for the same amount of time. Mice were sacrificed and their spleens removed 24, 72, and 144 hr after the exposure (MR or sham). Spleen cell suspensions were passed over nylon wool columns and then used as effector cells in a short-term natural killer cell cytotoxicity assay with 51Cr-labeled YAC-1 cells as target cells. The results showed no evidence of decreased cytotoxicity due to exposure to MR. On the contrary, at all three times after exposure and for all target-to-effector cell ratios, mean cytotoxicity was greater for MR-exposed groups than for sham-exposed groups. The results show that MR exposure has no adverse effect on the immune system, as evidenced by natural killer cell activity. 相似文献
994.
M C Bánki 《Orvosi hetilap》1987,128(27):1391-1395
995.
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998.
OBJECTIVE: With N omega-nitro-L-arginine, a potent inhibitor of nitric oxide synthesis, we tested the hypothesis that nitric oxide plays a functional role in the blunted pressor responsiveness seen during pregnancy. STUDY DESIGN: A group of six pregnant rats were instrumented on the fourteenth day of gestation and studied on days 19 and 20, as well as 7 days post partum. Another group of six virgin rats were similarly prepared and used 5 days after surgery. Blood pressure and heart rate were monitored in conscious freely moving animals before and during the administration of drugs or placebo. Results were analyzed, by one-way repeated-measures analysis of variance, with Dunnett's t test, or by paired t test where applicable. RESULTS: Basal mean arterial pressure and heart rate were 90.8 +/- 3.0 mm Hg and 330 +/- 6 beats/min in pregnant animals and 107.1 +/- 3.2 mm Hg and 315 +/- 7 beats/min in nonpregnant animals. Pressor responses to angiotensin II, vasopressin, and norepinephrine were attenuated in gravid animals. Infusion of N omega-nitro-L-arginine significantly and in a dose-dependent manner increased mean arterial pressure and reduced heart rate. These effects could be completely reversed by L-arginine administration. Changes in mean arterial pressure were higher during pregnancy as compared with postpartum values. N omega-nitro-L-arginine infusion potentiated pressor responses to all three vasopressors, resulting in dose-response curves that were significantly shifted to the left, making them virtually identical in pregnant and postpartum rats. CONCLUSION: Our data support the emerging view that nitric oxide plays a key role in the regulation of blood pressure during pregnancy. 相似文献
999.
A Salcedo E Molinero M P Echevarría J M Aguirre J Arzubiaga M M Iriarte 《Revista espa?ola de cardiología》1991,44(2):99-105
We've studied the prognostic significance of the electrocardiographic coronary reserve, evaluated by seried effort tests, in patients with stable angina and proved coronary disease. Seventy-three patients with stable angina, who performed 2 exercise tests (basal and after vasodilator therapy) were included. It's considered variable reserve when in the second test the ST-descent improves greater than or equal to 1 mm for equal or higher double product (43 patients) and fixed reserve when it doesn't (30 patients). All of them underwent to coronariography study. The exercise test was seried each term during the first year. Clinical follow-up lasted 3 years and we considered cardiac events: myocardial infarction, unstable angina, surgery, PTCA or death. Patients with fixed reserve had higher maximal ST-descent (2.5 +/- 0.7 vs 1.9 +/- 0.6; p less than 0.05), lesser effort-time (359 +/- 144 vs 430 +/- 112; p less than 0.05), and more severe coronary disease (score: 3.5 +/- 1.5 vs 2.4 +/- 0.8; p less than 0.01) as compared with variable reserve group. Unfavorable clinic evolution was similar in both groups (44.3% in the fixed reserve group and 34.8% in the variable reserve group). We verified that 92.3% of patients with variable reserve who didn't modify its character in a year had good evolution; 76.4% of patients who changed to fixed reserve had unfavorable evolution (significant association, p less than 0.01). We conclude that in patients with variable reserve, the periodic evaluation of the reserve character has important prognostic implication.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
The genetical types were classified according to the clinical findings and biochemical results in cases of 13 newborn/children suffering from various aminoacidopathies. The genetical types were: 3 neonatal and 4 infantile types were found out of 7 non-ketotic disease (MSUD) patient was infantile type with 9.1 per cent keto acid decarboxylase activity in leukocyte homogenate. Among the 3 histidinemic patients 1 was severe neonatal type and 2 cases were chronic types. The 2 treated tyrosinemic children proved to be type III. (chronic with rickets). 相似文献