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31.
Bolontrade MF; Stern MC; Binder RL; Zenklusen JC; Gimenez-Conti IB; Conti CJ 《Carcinogenesis》1998,19(12):2107-2113
In this study we have analyzed the vascular response induced in the two-
stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not
been explored in this model, which is the paradigm of multistage
carcinogenesis and a model for neoplastic lesions derived from exophytic
premalignant lesions (e.g. colon carcinoma, bladder papilloma). We
investigated if angiogenesis is involved in the formation of papillomas and
in the progression from papilloma to carcinoma. To this end we analyzed the
vasculature of normal and hyperplastic skin, focal epidermal hyperplasias
that are precursors of papillomas, papillomas at different stages and
squamous cell carcinomas. We also analyzed the vascularization of
papillomas induced in two strains of mice that differ in their
susceptibility to malignant progression. We show here that angiogenesis is
turned on in the earliest stages of papilloma formation. In late stages,
regardless of state of progression, the predominant response is an increase
in the size of blood vessels. Thus, in the SENCAR mouse model,
representative of exophytic tumors, the angiogenesis switch is a very early
event, probably mechanistically related to the development of the primarily
exophytic lesions. Therefore, the density of blood vessels cannot be used
as a predictor of malignant progression in this model.
相似文献
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A case of Gordon's syndrome (short stature, defective dentition, hyperkalemic, hyperchloremic acidosis, and chronic hypertension) complicating pregnancy is presented. Rigid salt restriction with diuretic therapy not only controlled the hypertension but also reversed the metabolic abnormalities. This is the first case report of a pregnancy complicated by this rare syndrome. 相似文献
34.
Seven oliguric women with preeclampsia were identified among patients admitted for obstetric care at Jefferson Davis or Hermann Hospitals in Houston, Texas. Urinary diagnostic indices (including urine-to-plasma ratios of creatinine, urea nitrogen, and osmolality) were generally consistent with a prerenal etiology for the observed oliguria. Conversely, invasive hemodynamic monitoring revealed a volume replete state in five of seven preeclamptic women studied. All patients were observed to have markedly elevated urinary sodium concentrations. The transient oliguria observed in these patients spontaneously resolved without diuretic or hyperosmolar agents. We conclude that oliguria is a poor index of volume status in preeclamptic women. Urinary diagnostic indices may also be misleading if used to guide fluid management in these patients. Finally, the clinical significance and therapeutic alternatives relating to preeclampsia-associated oliguria are discussed. 相似文献
35.
Over a 1-year period, seven eclamptic patients with repetitive seizures while receiving therapeutic levels of intravenous magnesium sulfate were evaluated by computerized axial tomography. In five patients brain abnormalities were identified, which included diffuse cerebral edema (one), cerebral venous thrombosis (two), and low density white matter (two). Clinical management of eclamptic women on the basis of structural central nervous system abnormalities documented by computerized tomography appears to warrant further investigation. 相似文献
36.
W Lee K A Ginsburg D B Cotton R H Kaufman 《American journal of obstetrics and gynecology》1986,155(5):999-1001
The antemortem diagnosis of amniotic fluid embolism has traditionally relied on the identification of amniotic fluid debris in the maternal circulation by central venous or pulmonary arterial catheterization. Pulmonary artery blood specimens from 14 term pregnant women with severe pregnancy-induced hypertension suggest that squamous or trophoblastic cells may be normally present in the maternal pulmonary circulation during the peripartum period and that their presence is not pathognomonic of clinically significant amniotic fluid embolism. 相似文献
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38.
Prevention of symptomatic patent ductus arteriosus with a single dose of indomethacin 总被引:1,自引:0,他引:1
To determine the efficacy of indomethacin to prevent the occurrence of symptomatic patent ductus arteriosus (PDA), a randomized clinical trial was conducted involving 32 preterm infants weighing 750 to 1500 g at birth who had hyaline membrane disease. By random assignment, 15 infants were given a single dose of indomethacin, 0.2 mg/kg intravenously, 24 hours after birth. Seventeen infants composed a control group for which indomethacin was reserved as treatment for symptomatic PDA. Birth weight, gestational age, male/female ratio, black/white ratio, and severity of disease were similar for both groups. Only one of the 14 survivors who received prophylactic indomethacin had symptomatic PDA, compared with nine of the 16 survivors in the control group (P = 0.007). There was no difference between the groups in development of bronchopulmonary dysplasia, duration of time endotracheal intubation, was required, duration in oxygen, duration to reach full feedings and regain birth weight, and duration of hospital stay. There was no difference between the two groups in incidence of intraventricular hemorrhage, and none developed necrotizing enterocolitis. These results indicate that the use of prophylactic indomethacin is beneficial in prevention of symptomatic PDA; the lack of differences in pulmonary sequelae or other complications may have been related to a population sample size not large enough to impart sufficient statistical power. 相似文献
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