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61.
BACKGROUND: Uterine cervical varix is a rare complication in pregnant women and can be the cause of obstetric hemorrhage in the vagina resulting in adverse events for both the mother and fetus. CASE: A 34-year-old Japanese woman was hospitalized at 18 weeks gestation because of cervical varix and placenta previa. Prophylactic tocolysis successfully controlled the obstetric hemorrhage. At 27 weeks gestation, emergent cesarean section was performed because of intractable hemorrhage from the marginal placenta previa. Intraabdominal findings revealed no vascular malformation of the uterus, and the operation was performed uneventfully. A speculum examination of the vagina and cervix at 1 month postpartum were unremarkable. CONCLUSION: It is important to recognize the clinical features and available treatments for cervical varix.  相似文献   
62.
The phthalate esters have been used as plasticizers for various plastic products, and their testicular toxicity has been reported. In this study, the effects of mono(2-ethylhexyl) phthalate (MEHP), one of the phthalate esters, on prepubertal rat testes in vitro were examined. The testes of 20-day-old Sprague Dawley (SD) rats were cut into smaller pieces and seeded in medium, and then the specimens were obtained for light and transmission electron microscopic observations. As a result, at 1 hr after exposure to MEHP, TUNEL-positive spermatogenic cells were identified, and they gradually increased in number in time- and dose-dependent manners. Ultrastructurally, apoptotic spermatogenic cells (characterized with chromatin condensation, cytoplasm shrinkage without membrane rupture, still-functioning cell organelles, and packed cell contents in membrane-bounded bodies), necrotic spermatogenic cells (characterized with swollen and ruptured mitochondria, plasma membrane lysis, spilt cell contents, and chromatin clumps), apoptotic Sertoli cells (highly condensed nuclei and nuclear membrane lysis) and necrotic Sertoli cells (marginated chromatins along the nuclear membrane, some swollen and ruptured cell organelles, e.g. mitochondria) could be identified. Conclusively, based on transmission electron microscopic observations, MEHP treatment may affect spermatogenic cells, and lead them to necrosis. Thus, testicular tissue cultures and cell cultures are of advantageous for screening testicular toxicity of chemicals.  相似文献   
63.
Beta-cryptoxanthin (beta-CRX) is a carotenoid pigment found in Satsuma mandarin (Citrus unshiu Marc.) fruit, which is heavily produced in Japan. In this study, we evaluated the seasonal changes in the serum beta-CRX level and investigated predictors of serum beta-CRX level by multiple linear regression analysis. Blood tests and self-administered questionnaires were used every other month for one year. The subjects were healthy volunteers, 15 males and 12 females. The serum beta-CRX levels increased dramatically as the intake of Satsuma mandarin increased; the maximum increase was noted in January. Multiple linear regression analysis showed that, in males, the serum beta-CRX level could be predicted by Satsuma mandarin intake, age and the month of blood sampling; however, it was inversely associated with alcohol and smoking habits. Conversely, in females, the serum beta-CRX concentration could be predicted by Satsuma mandarin intake, the month of blood sampling and age; however, it was inversely associated with body mass index. The results of multiple linear regression analysis suggest that the serum beta-CRX levels can be used to evaluate the intake volume of Satsuma mandarin. Furthermore, beta-CRX is a useful biomarker to estimate the beneficial effects of Satsuma mandarin intake in epidemiological studies.  相似文献   
64.
PURPOSE: To evaluate the transposition of the anterior superior oblique insertion as a treatment for cyclovertical diplopia accompanied by an awareness of tilted image perceived with the affected eye induced from limited macular translocation (LMT). DESIGN: Observational case series. METHODS: Transposition of the anterior part of the superior oblique tendon combined with or without vertical muscle surgery on the affected eye was retrospectively studied in seven patients. Clinical outcome was assessed for binocular and monocular vision. A successful result was defined as restoration of single binocular vision (SBV) at distance and near examined with the Bagolini test with disappearance of a tilted image perceived in the affected eye. RESULTS: Six of seven patients (86%) became unaware of tilted image, and three patients (43%) obtained successful results after the strabismus surgery. Of these three patients with successful results, one (33%) patient recognized metamorphopsia, whereas two (67%) of the three patients with unfavorable results reported metamorphopsia. Patients with successful results showed a visual acuity of 20/25 or better in the affected eye and a significantly smaller difference in visual acuity between the two eyes than those patients with unfavorable surgical results (0.133 logarithm of the minimal angle of resolution for SBV(+) vs 0.675 logarithm of the minimal angle of resolution for SBV(-); P =.0255). CONCLUSIONS: The relatively low success for restoration of SBV indicates that strabismus surgery is recommended for patients whose difference in visual acuity between the two eyes is small and who have a high level visual acuity of the affected eye.  相似文献   
65.
PURPOSE: We quantitatively evaluated the effects of arteriovenous (A/V) crossing sheathotomy on retinal circulation in patients with branch retinal vein occlusion (BRVO) accompanied by macular edema. DESIGN: Interventional case series. METHODS: In 18 consecutive patients (18 eyes) with BRVO accompanied by macular edema who underwent A/V crossing sheathotomy between August 1999 and April 2002, changes in retinal circulation after the surgery were evaluated by fluorescein videoangiography with a scanning laser ophthalmoscope and by image analysis using dye dilution technique. At a venule distal to the responsible A/V crossing site and a normal venule, the circulation time (T50) from the beginning of filling to 50% filling of the peak intensity was calculated. The time difference (DeltaT50) between T50 at the point on the affected venule and that at the point on the normal venule, which represents the filling delay at the venule distal to the A/V crossing site, was compared between before and early after the surgery. RESULTS: The preoperative DeltaT50 was 1.36 +/- 1.15 seconds (mean +/- SD), and the postoperative DeltaT50 was 0.72 +/- 0.77 seconds (P =.035, paired t test). In 11 of the 18 eyes, DeltaT50 decreased by 20% or more after the surgery. In the other 7 eyes, DeltaT50 was unchanged or slightly increased after the surgery. CONCLUSIONS: Although a randomized controlled study is needed to confirm the effectiveness of A/V crossing sheathotomy on visual function, this technique could be effective for improving the delay in perfusion in the affected venule.  相似文献   
66.
PURPOSE: To evaluate the effects of radial optic neurotomy (RON) on retinal circulation in patients with central retinal vein occlusion (CRVO) by indocyanine green (ICG) videoangiography and a computer-assisted image analysis. DESIGN: An interventional case series. METHODS: RON was performed in 15 eyes of 15 patients with CRVO. Within 72 hours before the surgery and at 3 months after the surgery, ICG videoangiography was performed with a scanning laser ophthalmoscope, and the images were transferred to a computer. Two measurement points were selected, one on a main retinal artery close to the optic disk and the other on the corresponding retinal vein. At each point, fluorescence intensities were serially measured, and dye dilution curves were obtained. Retinal circulation times (DeltaT(50)) before and after the surgery were calculated. RESULTS: Mean preoperative DeltaT(50) was 6.46 +/- 1.36 seconds, and mean postoperative DeltaT(50) was 6.80 +/- 2.50 seconds. In 8 of 15 eyes, T(50) decreased by 6.8% to 29.6% after the surgery. In the seven eyes that developed chorioretinal anastomosis (CRA) at the site of RON, DeltaT(50) decreased after the surgery. In contrast, DeltaT(50) decreased postoperatively in only one of the eight eyes without CRA. Best-corrected visual acuity improved significantly after the surgery in the group of eyes with improvement in DeltaT(50), but not in the group of eyes without improvement in DeltaT(50). CONCLUSIONS: Some degree of retinal circulation improvement occurred in approximately half of these eyes, which appears to be correlated with the development of CRA.  相似文献   
67.
68.
In the current study, we investigated interindividual variability of the 2-hydroxylation, 3-glucuronidation, and 3-sulfation of ethynylestradiol (EE2) using human liver microsomes and cytosol. Km values for the 2-hydroxylation and 3-glucuronidation in pooled liver microsomes and for the 3-sulfation in pooled liver cytosol were 3.34, 23.3, and 2.85 microM, respectively. Vmax/Km (ml/min/g liver) was highest for the 3-sulfation, followed by 2-hydroxylation, suggesting that 3-sulfation is the major metabolic pathway of EE2 in human liver. All further studies were performed at a substrate concentration of 0.1 microM. Microsomal 2-hydroxylation and 3-glucuronidation activities ranged from 0.21 to 5.02 (2.04+/-1.34, mean+/-S.D., n=35) and 0.20 to 4.84 (1.20+/-1.00, n=35) pmol/min/mg protein, respectively. Cytosolic 3-sulfation activity ranged from 4.2 to 24.3 (11.8+/-4.4, n=21) pmol/min/mg protein. All the measured enzyme activities were neither gender-related nor age-dependent, except that 2-hydroxylation was significantly higher in females than in males (p<0.05). The relative contribution of CYP3A to the 2-hydroxylation in liver microsomes was estimated from the degree of inhibition by 1 microM ketoconazole. The degrees of inhibition were between 17.8 and 78.0% (51.6+/-16.0%, n=27). These results indicate that there are large interindividual differences in the enzyme activities towards the respective metabolic pathways of EE2 and the relative contribution of CYP3A to the 2-hydroxylation of EE2 in human liver.  相似文献   
69.
Urinary acidification in extremely low birth weight infants   总被引:1,自引:0,他引:1  
Premature infants often present metabolic acidosis without protein load in the early neonatal period, around days 4–6. In order to elucidate the cause of acidosis, we investigated urinary acidification of infants in the early neonatal period.

Urine pH, fractional excretion of HCO3 (FEHCO3), excretion of HCO3 and NH4+ of the appropriate-for-date infants were measured on days 0–2 and on days 4–6 of life.

Extremely low birth weight (ELBW) infants showed higher urine pH than more than 1500 g birth weight infants. FEHCO3 and HCO3 excretion were of high values in ELBW infants on days 0–2, but decreased on days 4–6. Urine NH4+ excretion rate was lower in ELBW infants than in birth weight more than 1000 g on days 0–2 of life and still remained at a low rate on days 4–6.

These data indicated that insufficiency of NH4+ excretion is the main cause for metabolic acidosis of ELBW infants in the early neonatal period.  相似文献   

70.
Tubulin is the major constituent protein of microtubules. In mammals, there are seven beta-tubulins and six alpha-tubulins. Each beta-tubulin isotype has a unique tissue distribution. The purpose of this study was to describe the distribution of tubulin beta II in normal and neoplastic human tissues with immunohistochemical techniques. We obtained normal tissues from 33 cases (8 fetuses, 17 neonates, 3 children and 5 adults) and 121 samples of neoplastic tissue from surgical specimens or at autopsy. Immunohistochemical staining for tubulin beta II was performed using a monoclonal antibody, KNY379 developed in our laboratory. Tubulin beta II was detected in various normal tissues, particularly in fetal and neonatal tissues, such as the nervous system, pulmonary alveoli, bronchioles and bronchi, colon, pancreatic ducts and acini, renal convoluted tubuli, skin epidermis, body cavity mesothelial cells, smooth muscle and thymus. In the adult, broad expression was also observed; however, the immunoreactivity was weaker and the extent of its distribution decreased with age. In neoplastic tissues, tubulin beta II immunoreactivity was detected in various nervous system neoplasms and other neoplasms such as pancreatic solid cystic carcinoma, pleomorphic adenoma, Warthin's tumor, nephroblastoma, basal cell carcinoma and malignant mesothelioma. We conclude that our monoclonal antibody, KNY379, may be useful as a marker of nervous system neoplasm, pancreatic solid cystic carcinoma, pleomorphic adenoma, Warthin's tumor, nephroblastoma, basal cell carcinoma and malignant mesothelioma.  相似文献   
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