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991.
We describe three pediatric patients in whom locally infused streptokinase at a dose of 50 U/kg/hr was used successfully to treat thrombosis in a major artery, a major vein, and a systemic-to-pulmonary arterial graft. Complications, including hemorrhage and distal embolization, were minimized by careful monitoring of the coagulation status of the blood and by avoiding rapid infusions. Selective thrombolytic therapy appears to be as effective in infants as in adults. Because the dose required is reduced, the incidence of complications is lower than with systemic infusions.  相似文献   
992.
Recurrence of Wilms tumor after apparent cure   总被引:1,自引:0,他引:1  
The recurrence of Wilms tumor after a 5-year disease-free interval is rare. We present two patients who had recurrent disease after a disease-free interval of greater than 7 years. Three additional patients, registered with the National Wilms Tumor Study who had a recurrence after 5 years, are also described. Of these three patients, two had nephroblastomatosis. Because more patients are achieving long-term survival, careful surveillance after apparent "cure" is recommended, particularly if nephroblastomatosis is identified in the original nephrectomy specimen.  相似文献   
993.
The factor by which the villous surface area is enlarged owing to the presence of microvilli has been evaluated with quantitative analyses in human placental tissues from mid-gestation to term. It has shown that, between 25 and 36 weeks of gestation, the peripheral villous surface area is enlarged by a constant factor of approximately 9.47 +/- 0.28 (mean +/- s.d.). Then, from 36 weeks to term, it has shown a significant decrease in the microvillous surface enlargement factor (9.44 to 7.67; P less than 0.01). Consequently, the actual surface area of exchange between mother and fetus was shown to be significantly decreased during that same period (93.91 to 67.02 m2; P less than 0.01). On a functional basis, these findings support the theory that, during that last four weeks of pregnancy, the increasing physiological needs of the fetus are probably met by profound functional changes in the permeability and transfer functions of the cells that constitute the placental barrier.  相似文献   
994.
To determine whether acute alcohol ingestion during pregnancy could affect fetal myocardial function, studies were carried in six chronically catheterized fetal sheep during maternal alcohol infusion. Absolute ethyl alcohol (0.8 ml/kg) was administered to the mother over 10 minutes via the jugular vein. These infusions were repeated every 30 minutes during 3 hours, and peak maternal and fetal blood concentrations close to 200 mg/dl alcohol were reached. Fetal PCO2 decreased from a baseline of 43.15 +/- 3.75 to 36.13 +/- 2.6 torr 1 hour after the start of alcohol infusion (P less than 0.05). Similarly, pH rose from 7.37 +/- 0.027 to 7.44 +/- 0.015 (P less than 0.05). Both values returned to baseline level at the end of alcohol infusion. PO2 remained within physiologic limits. The systolic time intervals of the fetal heart showed a rapid and prolonged modification. The pre-ejection period from 58 +/- 8 to 66 +/- 4 msec (P less than 0.05) during the infusion; this change was related to an increase in the isometric contraction period. The ratio of the pre-ejection period over the ejection time was also significantly increased (P less than 0.01), and remained elevated until the end of the experiment (12 hours). A rise in fetal systolic and diastolic pressures was observed at about 2 hours after the start of the alcohol infusion, and lasted 4 hours. This study suggests that an episode of maternal alcohol intoxication causes rapid depression of fetal myocardial contractility that is maintained several hours after cessation of alcohol ingestion.  相似文献   
995.
996.
The role of the adhesion molecule CD44H in the peritoneal adhesion and invasion of cancer cells was assessed using cell lines with low and high peritoneal seeding ability, OCUM-2M (2M) and OCUM-2MD3 (2MD3), respectively. The in vitro binding ability to peritoneal components (mesothelial cells, fibroricetin and type I collagen) and invasive ability of 2MD3 cells were higher than those of 2M cells. The expression level of CD44H on 2MD3 cells was higher than that on 2M cells as determined by western blot analysis and flow cytometry. The adhesiveness of 2MD3 cells to hyaluronic acid, which is expressed on the surfaces of mesothelial cells, was greater than that of 2M cells. The binding ability of 2MD3 cells to mesothelial cells was inhibited in the presence of anti-CD44H monoclonal antibody, but that of 2M cells was not. These results suggested that the 2MD3 cell binding to mesothelial cells is regulated by the CD44-hyaluronic acid dependent system. The in vitro binding to submesothelial components and the invasiveness of 2MD3 cells were also inhibited in the presence of anti-CD44H antibody. The in vivo inoculation of 2MD3 cells treated with an anti-CD44H antibody resulted in a significant prolongation of survival time as compared with control mice that were inoculated with 2MD3 cells alone. In conclusion, CD44H was associated with attachment not only to hyaluronic acid on mesothelial cells, but also to peritoneal stromal components. Thus, CD44H may play an important role in cancer cell binding and invasion in the peritoneal dissemination of scirrhous gastric cancer cells.  相似文献   
997.
人参果总皂甙对乳鼠原代培养心肌细胞的作用   总被引:6,自引:0,他引:6  
本文报告了人参果总皂甙对乳鼠原代培养心肌细胞作用的实验研究。实验结果表明:人参果总皂甙具有促进乳鼠培养心肌细胞DNA合成的作用;对缺糖缺氧培养的缺氧性损伤的心肌细胞具有保护作用。  相似文献   
998.
The relationship of symptoms and signs to age and the reasons for consulting a physician were analyzed in 110 cases of culture-proven childhood bacterial meningitis. H. influenzae caused 74, meningococci 28, pneumococci 6 and streptococci 2 of the cases. Apart from fever (present in 94%), the most common symptoms according to age were as follows: 1–5 months: irritability (85%), 6–11 months: impaired consciousness (79%), 12 months or more: vomiting (82%) and neck rigidity (78%). Absence of neck rigidity at diagnosis was associated with young age (<12 months, P<0.001) and, in older children, to a short duration of symptoms (P<0.01) but not to the degree of CSF pleocytosis. Symptoms of meningitis caused by H. influenzae differed from those of meningococcal meningitis. Meningitis should be suspected in irritable or lethargic febrile children despite absence of neck rigidity. Fever and vomiting were the most frequent reasons for consulting a physician (60% and 31%, respectively). Despite the frequency and alarming character of irritability, impaired consciousness and neck rigidity, their presence led infrequently to a consultation (6%, 22% and 3%, respectively). Parental ignorance of such symptoms or of their importance may cause treatment delay, despite readily available medical services.Abbreviation CSF cerebrospinal fluid  相似文献   
999.
Inadequate treatment of syphilis in pregnancy   总被引:6,自引:0,他引:6  
Pregnant women with untreated syphilis have high rates of adverse pregnancy outcome. Early syphilis in pregnancy, if not treated, results in 40% loss either by spontaneous abortions, stillbirth, or perinatal death. Another 40% of such pregnancies result in an infant born with congenital syphilis. Only 20% of such pregnancies result in a normal infant. Currently recommended treatment of early syphilis in pregnant women uses a dosage of 2.4 million U of benzathine penicillin G. Because of the potentially disastrous effect syphilis has on pregnancy outcome, the occurrence of any treatment failure must be considered seriously. In this brief report we present clinical summaries of four pregnant women treated for syphilis who represent probable treatment failures.  相似文献   
1000.
Chlamydia trachomatis, Mycoplasma hominis, and Ureaplasma urealyticum are genital agents that are being increasingly implicated in infectious pregnancy complications and abnormal pregnancy outcomes. We measured the in vitro activity of clindamycin against strains of these three agents which were isolated from pregnant women. For 30 strains of C. trachomatis, the median minimal inhibitory concentration was 1.0 microgram/ml (range, 0.25 to 2.0 micrograms/ml). For 27 strains of M. hominis, the median minimal inhibitory concentration was 0.12 microgram/ml (range, 0.06 to 0.25 microgram/ml) and the median minimal bactericidal concentration was 0.5 microgram/ml (range, 0.06 to 2.0 micrograms/ml). For 27 strains of U. urealyticum, the mean minimal inhibitory concentration was 4 micrograms/ml (range, 1.0 to 32.0 micrograms/ml) and the mean minimal bactericidal concentration was 32.0 micrograms/ml (range, 4.0 to 128 micrograms/ml). Thus in vitro clindamycin would appear to be highly active against pregnancy-associated strains of M. hominis, less active against strains of C. trachomatis, and least active against strains of U. urealyticum. Since M. hominis has been strongly linked to postabortal fever and to postpartum fever and endometritis, our results indicate that clindamycin should be evaluated in treatment trials in pregnancy aimed at prevention of M. hominis-induced morbidity as well as in treatment of the complications themselves.  相似文献   
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