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BACKGROUND: Destruction of uterine vasculature is a common phenomenon in gestational trophoblastic tumors. The authors categorized such uterine vasculature by color Doppler ultrasound and studied its clinical significance. METHODS: Color Doppler ultrasound was performed in 28 patients with gestational trophoblastic tumors. The vascular morphologic manifestations were recorded, and the peak systolic velocity and resistance index of uterine artery were calculated. Serum beta-human chorionic gonadotropin (hCG) levels were measured periodically to monitor chemotherapy response. Seventeen uneventful postmole uteri were used as controls. Two-tailed Student's t-test and Fisher's exact test were used for statistical analysis. RESULTS: The gestational trophoblastic tumors were categorized as diffuse type (N = 7), lacunar type (N = 16), and compact type (n = 5) according to their vascular patterns. The mean serum beta-hCG level at diagnosis in diffuse type lesions (6608 +/- 6320 mIU/mL) was significantly lower than in the lacunar type (40462 +/- 39735 mIU/mL; P = 0.04) and compact type (212114 +/- 205126 mIU/mL; P = 0.02), whereas the level in compact type lesions was significantly higher than in the lacunar type (P = 0.003). Lacunar type lesions exhibited a significantly lower uterine artery resistance index (0.51 +/- 0.13) than diffuse type (0.66 +/- 0.10; P = 0.03) or compact type lesions (0.70 +/- 0.06; P = 0.02). All lesions exhibited significantly higher peak systolic velocity than control subjects (P < 0.001); however, no significant difference was observed among them. Brief courses (< 5 cycles) of chemotherapy cured more diffuse type (6 of 7) than lacunar type (3 of 15, P = 0.006) or compact type lesions (0 of 5, P = 0.008). Histopathologic diagnosis was available for 11 lesions. They were invasive mole in seven lacunar type lesions and choriocarcinoma in four compact type lesions. CONCLUSION: Vascular morphologic patterns of gestational trophoblastic tumors by color Doppler ultrasound correlated well with beta-hCG levels, uterine hemodynamics, chemotherapy response, and possibly the histopathologic diagnosis.  相似文献   
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Urinary calcareous disease related to laxative abuse is rare. The gastrointestinal loss of fluid and electrolytes leads to chronic depletion of the urinary volume, relative supersaturation and many other pathophysiologic derangements. These calculi are generally radiolucent with uric acid and ammonium acid urate as major components. We report on a female patient with frequent, repetitive formation of urinary calculi and rapid double J stent encrustation, which were related to the chronic abuse of bisacodyl. Although these stones can be fragmented successfully by extracorporeal shockwave lithotripsy, it seems that the better treatment for this type of stone formation is to avoid the abuse of laxatives.  相似文献   
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Aspirin (ASA) triggers the formation of 15-epi-lipoxins (15-epi-LXs or ATL [ASA-triggered LX]), which are potent bioactive eicosanoids that may contribute to the therapeutic impact of ASA. To elucidate the role of these new compounds in vivo, it is essential to establish quick and sensitive detection methods. To this end, we prepared an enzyme-linked immunosorbent assay specific for 15-epi-LXA4 that proved to be highly sensitive (IC50 approximately 50 pg, minimum detection approximately 3.5 pg) and stereoselective. The amounts of 15-epi-LXA4 generated by human neutrophils from peripheral blood of healthy volunteers using this enzyme-linked immunosorbent assay were in agreement with those values obtained by liquid chromatography. Formation of 15-epi-LXA4 was cell ratio-dependent during THP-1 (a monocytic leukemia cell line)-neutrophil interactions with ASA-treated cells, and 15-epi-LXA4 was not detected with either cell type alone. Generation of 15-epi-LXA4 was also examined in murine peritonitis with ASA administration. Exudates from ASA-treated mice showed increased production of 15-epi-LXA4 that was diminished by indomethacin, a blocker of ASA-dependent acetylation of prostaglandin G/H synthase. A cytochrome P450 inhibitor administered in the presence of ASA did not prevent 15-epi-LXA4 formation, which suggests that P450 does not significantly contribute to formation of 15-epi-LXA4 in this murine model. These results indicate that the new enzyme-linked immunosorbent assay is both sensitive and selective for 15-epi-LXA4 and that 15-epi-LXA4 is produced by human leukocyte-leukocyte interactions. In addition, 15-epi-LXA4 is generated by inflammatory exudates when ASA is administered during murine peritonitis and when prostaglandin G/H synthase is upregulated and acetylated. This assay should provide rapid means to investigate 15-epi-LXA4 generation in both cellular and animal models.  相似文献   
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A moderate level of morbidity through acute respiratory diseases (ARD), of the upper tract, viral pneumonia and clinical influenza was recorded during November 1994 and April 1995 in the South-East area of Romania (nine districts). By virological and serological investigation adenosyncytial respiratory, parainfluenza type 3 and influenza type B viruses were found to be the most frequent etiological agents of these infections which affected especially the babies and the children of 1-14 years of age. Sporadic influenza outbreaks were noticed from which influenza strains of virus were isolated, antigenically related to the prototype strain A/Johannesburg 33/94.  相似文献   
76.
BACKGROUND: Macrophage migration inhibitory factor (MIF) plays a pivotal role in immune-mediated diseases. Despite the long-standing association of MIF with the delayed-type hypersensitivity response, the potential role of MIF in allograft rejection is unknown. METHODS: MIF expression was assessed by in situ hybridization and immunohistochemistry staining in 62 biopsies of human renal allograft rejection and in normal human kidney. RESULTS: MIF mRNA and protein is constitutively expressed in normal kidney, being largely restricted to tubular epithelial cells, some glomerular epithelial cells, and vascular smooth muscle cells. In both acute and chronic renal allograft rejection, there was marked up-regulation of MIF mRNA and protein expression by intrinsic kidney cells such as tubular epithelial cells and vascular endothelial and smooth muscle cells. There was also MIF expression by infiltrating macrophages and T cells. Of note, macrophage and T cell infiltrates were largely restricted to areas with marked up-regulation of MIF expression, potentially contributing to the development of severe tubulitis and intimal or transmural arteritis. Quantitative analysis found that increased MIF expression in allograft rejection gave a highly significant correlation with macrophage and T cell accumulation in both the glomerulus and interstitium (P<0.001). In addition, the number of MIF+ tubules and interstitial MIF+ cells correlated significantly with the severity of allograft rejection (P<0.01), and the loss of renal function (P<0.01). In contrast, no up-regulation of renal MIF expression and no leukocyte accumulation was seen in allograft biopsies without evidence of rejection. CONCLUSIONS: This is the first study to demonstrate that local MIF expression is up-regulated during allograft rejection. The association between up-regulation of MIF expression, macrophage and T cell infiltration and the severity of renal allograft rejection suggests that MIF may be an important mediator in the process of allograft rejection.  相似文献   
77.
Plasma beta-hydroxybutyrate concentrations were measured in the offspring of rats that were fed either a control (20% protein) diet or low-protein (8% protein) diet during pregnancy and lactation. Low-protein offspring had significantly lower plasma beta-hydroxybutyrate compared with controls in the fed state (P < .04) and after fasting for 24 hours (P < .001) and 48 hours (P < .04). There were no differences in blood glucose, acetoacetate, plasma glucagon, cholesterol, or glycerol between control and low-protein offspring. However, plasma nonesterified fatty acids (NEFAs) were significantly higher in low-protein offspring in the fed state (P < .05). In contrast, plasma triglycerides and insulin were significantly lower in low-protein offspring compared with controls when fed (P < .001) and after a 24-hour fast (P < .001). These results suggest that poor maternal and early postnatal nutrition can have long-term effects on ketone body metabolism in the offspring during adulthood. This apparent ketosis resistance is similar to that observed in some forms of human diabetes.  相似文献   
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The processes of activation and deactivation of ribulose-1,5-bisphosphate carboxylase purified from wheat have been investigated. Two forms of the enzyme are indistinguishable in terms of ribulose-1,5-bisphosphate carboxylation and oxidation but exhibit different rates of activation. One form is slowly activated in saturating CO2 and Mg2+ at moderate temperatures (t0.5 approximately 120 min at 25 degrees C), the other form rapidly activated (t0.5 approximately 8 s). In the presence of the effectors 6-phosphogluconate or NADPH, significantly lower concentrations of the activating co-factors can achieve full activation of both enzyme species. However, with another effector, fructose 1,6-bisphosphate, for the slowly activating species the mode of action is the same as with 6-phosphogluconate or NADPH, whereas the activation of the rapidly activating species is significantly inhibited. The substrate, ribulose 1,5-bisphosphate, also inhibits this rapid activation process. A mechanism is proposed for the reactions involving activation that accounts for the differential rates of activation and the response to effectors.  相似文献   
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