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71.
Newlin  N; Silver  TM; Stuck  KJ; Sandler  MA 《Radiology》1981,139(1):155-159
Ultrasonic features of 21 surgically confirmed pyogenic liver abscesses in 18 patients were analyzed. Typical lesions were round or ovoid with a discrete, irregular, echo-poor margin. The number and intensity of internal echoes and sound transmission were variable. Such lesions can be aspirated percutaneously for definitive preoperative diagnosis. Pyogenic liver abscesses appear to have more ragged walls and are less frequently elliptical or multilocular than abscesses elsewhere in the abdomen.  相似文献   
72.
73.
Ultrasound diagnosis of hydrocolpos and hydrometrocolpos   总被引:1,自引:0,他引:1  
Wilson  DA; Stacy  TM; Smith  EI 《Radiology》1978,128(2):451
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74.
Peroxisomal beta-oxidation of fatty acids and the activities of glutathione-metabolizing enzymes in rat liver were measured after administration of 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetic acid (MCPA), clofibrate [ethyl], 2-(p-chlorophenoxy)-2-methylpropionate], glyphosate (N-phosphonomethyl glycine, a herbicide not structurally related to phenoxy acids) or saline for 14 days. beta-Oxidation increased by 6-fold in the group given clofibrate, 3-fold in the 2,4-D-treated group, and 2-fold in the MCPA-treated group over the level in the controls (saline-treated). Glyphosate did not increase beta-oxidation. No significant change in reduced glutathione content from that in controls was found in any of the treated groups. Glutathione reductase activity increased by about 40% after administration of either 2,4-D or MCPA, and glutathione peroxidase activity increased by 30% in animals given MCPA. A slight decrease in glutathione S-transferase activity was found in the group treated with clofibrate. The marked increases in peroxisomal beta-oxidation of fatty acids were accompanied by only minor changes in the activities of enzymes involved in glutathione-dependent inactivation of organic hydroperoxides and other oxygen-centred reactive agents.  相似文献   
75.
76.
In the perinatal period, glucocorticoids are frequently administered to enhance pulmonary maturity or prevent chronic lung disease of prematurity. Recently, it has been suggested that the perinatal exposure to glucocorticoids can be associated with unfavorable neurologic development. We studied the hypothesis that 24-h pretreatment with glucocorticoid might modify cerebrovascular responses to high and low partial arterial CO(2) tension in newborn animals in vivo. A closed cranial window was implanted over the left parietal cortex of 20 anesthetized ventilated newborn (<3 d old) pigs. The actual experiments were carried out in 15 pigs: eight pretreated with a total dose of 6 mg/kg of dexamethasone and seven controls. Five pigs were used for preliminary experiments as described in the text. Pial arteriolar diameters were measured during 1) baseline conditions (normocapnia), 2) hypercapnia induced by ventilating the animals with a gas mixture containing 10% CO(2), or 3) hyperventilation with resultant hypocapnia. Under these conditions, the concentrations of 6-keto-PGF(1alpha) in the CSF were measured in five experimental animals and six controls. In summary, the dexamethasone pretreatment 1) attenuated the hypercapnia-induced dilator responses of pial arterioles and prevented the hypercapnia-associated fall in mean arterial blood pressure; 2) caused moderate, although not statistically significant, diminution in 6-keto-PGF(1alpha) levels in the CSF during baseline; 3) blocked hypercapnia-induced elevation of 6-keto-PGF(1alpha); and 4) enhanced vasoconstrictive arteriolar responses to hyperventilation. We speculate that in the clinical setting, the dexamethasone effects may compromise the adjustments of global or regional cerebral blood flow to changing physiologic states in neonates.  相似文献   
77.
The pathophysiology of preeclampsia is incompletely understood, but the familial nature of the disease has long been recognized. Recent genome-scan studies have indicated linkage at the p23 region of chromosome 2. We have previously reported microsatellite marker association at chromosome region 2p13 in patients with obstetric cholestasis. We conducted population-based association screening with microsatellite markers to find potential preeclampsia-associated loci on chromosome region 2p13-p12 and to test whether preeclampsia and obstetric cholestasis share a single risk locus. The study was carried out among 115 unrelated control women, 133 preeclamptic women and 57 cholestatic women. Screening with microsatellite markers at the 2p13-p12 region revealed that the marker D2S286 was significantly associated with obstetric cholestasis in the overall association analysis (P=0.03), while it revealed only borderline association with preeclampsia (P=0.08). However, single allele association analysis indicated that both preeclampsia and obstetric cholestasis showed a statistically significant association with a common allele (P < 0.05), which was overrepresented in both the obstetric cholestasis (0.42) and preeclamptic (0.37) groups when compared with the control group (0.28). In conclusion, These findings suggest a possible genetic link between chromosome region 2p13-p12, preeclampsia and obstetric cholestasis. More specifically, these data suggest that there may be a common risk locus associated with both obstetric complications located in the vicinity of the 2p13-p12 association region.  相似文献   
78.
OBJECTIVE: We wished to determine whether genetic variability in the gene encoding endothelial nitric oxide synthase (eNOS) modifies individual susceptibility to the development of preeclampsia. METHODS: The study involved 132 preeclamptic and 113 healthy control pregnant women who were genotyped for the Glu298Asp polymorphism in the eNOS gene. Chi(2) analysis was used to assess genotype and allele frequency differences between preeclamptic women and controls. RESULTS: A statistically similar allelic distribution of eNOS Glu298Asp polymorphism was observed in the two groups, with the frequency of the variant G allele being 74.6% in the preeclampsia group and 67.7% in the control group (P = .091; odds ratio 1.40, 95% confidence interval 0.95, 2.01). Accordingly, the genotype distribution of the NOS polymorphism in the preeclamptic and control groups was found to be similar (P = .233). CONCLUSION: These genotype data in subjects from eastern Finland were not suggestive of an important contribution of the Glu298Asp polymorphism in the NOS gene on preeclampsia across populations. However, the observed association between the G allele and disease risk, of borderline significance, may imply that other polymorphism(s) in the gene may modify disease risk.  相似文献   
79.
We evaluated whether hysterectomy with ovarian conservation (HYX) has an effect on bone metabolism and density in 176 healthy Caucasian postmenopausal women aged 48-59 years. Bone properties of the hip, spine, radius, tibia, and calcaneus were measured using different bone assessment modalities. In addition, bone turnover was assessed using serum bone-specific alkaline phosphatase (BAP), osteocalcin (OC), and tartrate-resistant acid phosphatase (TRAP) 5b as biomarkers. Our results showed that women having HYX had a significantly lower level of OC ( P = 0.017) and a marginally lower level of TRAP 5b ( P = 0.051) and higher bone mineral density (BMD) of the femoral neck ( P = 0.037) and lumbar spine ( P= 0.001) than women with no history of HYX. In addition, the cortical BMD and bone strength index (I(polar)) of the tibia also showed higher values at different sections in women having HYX than women with no history of HYX ( P = 0.055 to P< 0.005). These results suggest that the uterus may have a role in regulating bone metabolism that has not been detected previously.  相似文献   
80.
The objective of the study was to investigate the association between placental weight and birthweight in appropriate (AGA) and small for gestational age (SGA) infants. Placental weight, birthweight and their ratio in chromosomally normal singleton pregnancies with SGA (n=1569) and AGA (n=15 047) infants were compared, and their determinants were studied by logistic regression. SGA infants had 24 per cent smaller placentae than AGA infants when gestational age was used as a covariate. Placental actual weight was also lower in SGA infants than in AGA infants of the same birthweight (P< 0.001). SGA infants had smaller placentae than the controls, suggesting that fetal growth depends on the actual weight of the placenta. Future studies should evaluate whether growth restriction could be reversed by therapeutic approaches increasing placental weight.  相似文献   
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