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991.
Endovaginal ultrasound (US) was performed in 38 pregnant women at 5-12 menstrual weeks, when the initial transabdominal sonograms had been considered inconclusive or equivocal. Clinical follow-up disclosed 32 intrauterine pregnancies (12 living, 18 spontaneous incomplete abortions, and two embryonic demises) and six ectopic pregnancies. In the 32 intrauterine pregnancies (normal and abnormal), the correct diagnosis was made in all cases with endovaginal US. The endovaginal images demonstrated the intrauterine embryo, its heart motion, and the yolk sac more clearly and more often when these structures were not apparent on the transabdominal scans. Abnormal gestational sacs were better resolved. In the six cases of ectopic pregnancy, while an extrauterine ectopic sac was visualized in only three, absence of an intrauterine gestational sac was confirmed in all cases with endovaginal scanning. No endovaginal study yielded less information than its transabdominal counterpart. Endovaginal sonography is likely to be diagnostic when transabdominal images fail to yield a definitive diagnosis in early pregnancies.  相似文献   
992.
本文用微型计算机对在手动式分光光度计上测得的吸收光谱数据进行处理,以导数光谱系数倍率法不经预先分离直接测定小儿退烧片中阿司匹林的含量,方法简便、快速,不需特殊仪器,易于推广。平均百分回收率为99.74±0.46(n=9)。同时还用双波长法测定了另一组分醋氨酚的含量,平均百分回收率为99.54±0.52(n=9)。结果满意,可用于多组分药物制剂的分析。  相似文献   
993.
This study documents the changes in the percentages of advanced maternal age (AMA) pregnancies in the United States and in Washington State, underlying demographic factors, the impact on the predicted incidence of Down syndrome, and its impact on Down syndrome screening. Data on births in the United States from 1933 to 2002 were obtained from publications and the website of the National Center for Health Statistics. Data for Washington State were obtained from the website of the Washington State Department of Health. Information on births at Swedish Medical Center was obtained from hospital records. The percentage of AMA pregnancies in the US was about 14% before World War II, dropped steadily to about 5% in the 1970s and rose since the 1980s to about 14% in 2002. AMA Fractions are greatest among non-Hispanic Caucasians and Asian/Pacific Islanders, women who have college education and beyond, and are married. However, since 1980, the AMA Fractions have increased across all racial/ethnic groups, educational levels, and married and unmarried women. In Washington State in 2001, the overall AMA Fraction was about 14%, but there was considerable variation in the AMA Fraction across counties. In 1980, AMA pregnancies accounted for about 25% of pregnancies with Down syndrome in the United States. In 2002, AMA pregnancies accounted for more than 50% of Down syndrome pregnancies. Given the current AMA Fraction, offering amniocentesis to women of age 35 and above would result in one in seven pregnant women undergoing amniocentesis. Based on likelihood ratios, AMA as a screening strategy for Down syndrome is significantly inferior to combined serum and sonographic screening.  相似文献   
994.
Second to diabetes mellitus, thyroid diseases are the most common endocrinopathies seen in pregnancy. The incidence of post-partum thyroid dysfunction (PPTD) in women with type 1 diabetes mellitus is three-fold increased. We determined the incidence of thyroid abnormalities in a well-defined group of young subjects with type 1 diabetes and in an age-matched healthy controls during and six months after pregnancy in an area of mild iodine deficiency. Twenty-five out of twenty-eight pregnant women completed the study. Fifteen were affected by type 1 diabetes and ten were controls. Our protocol of study consisted of four evaluations of each subject: in the first, in the second trimester, at delivery and six months after. At each control the patients were submitted to physical examination, thyroid ultrasonography, and determination of fT3, fT4, TSH, Antithyroglobulin antibodies (TgAbs), Antithyroperoxidase antibodies (TPOAbs). The variation of thyroid volume is statistically significant in both the diabetics and in the controls during the different times of observations. Four out of the fifteen diabetic pregnant patients (27%) developed a thyroid disease: two cases of post-partum thyroiditis (PPT) and two cases of euthyroid benign nodular goiter, as confirmed by cytological examination. Two out ten controls (20%) developed positive antibodies (TPO Abs and TgAbs) since the first observation and showed an autoimmune thyroiditis six months after delivery. Both of them showed a familial history of thyroid disease. Our study suggests that in an area of mild iodine deficiency the incidence of thyroid autoimmunity in pregnant women is similar, whether diabetic or not; moreover, thyroid volume is increasing in the diabetics as much as in the non diabetics during pregnancy.  相似文献   
995.
996.
Detection of chronic endometritis at fluid hysteroscopy   总被引:1,自引:0,他引:1  
STUDY OBJECTIVE: Chronic endometritis is a subtle condition that is difficult to detect; however, it may cause abnormal uterine bleeding and infertility. Few data exist about the appearance of chronic endometritis at fluid hysteroscopy and about the value of diagnostic fluid hysteroscopy in the detection of this condition. In our experience, at fluid hysteroscopy chronic endometritis is characterized by consistent association of stromal edema and either focal or diffuse hyperemia; in some cases, this finding is associated with endometrial micropolyps (less than 1 mm in size). This study attempted to describe diagnostic criteria for chronic endometritis at fluid hysteroscopy and assess the diagnostic accuracy of fluid hysteroscopy in the detection of this condition. DESIGN: Retrospective Study (Canadian Task Force classification II-2). SETTING: University hospital. PATIENTS: Nine hundred-ten women in whom hysteroscopy was indicated. INTERVENTIONS: Fluid hysteroscopy followed by endometrial biopsy. MEASUREMENTS AND MAIN RESULTS: Sensitivity, specificity, positive and negative predictive values, and accuracy of fluid hysteroscopy in the detection of chronic endometritis, based on the association of edema; hyperemia; and, if present, micropolyps were calculated. Based on the presence of hyperemia and edema, chronic endometritis was diagnosed in 158 patients (17.4%); in 61 patients (6.7%), micropolyps also were present. Histology confirmed the diagnosis in 101 patients (63.9% of positive cases at hysteroscopy) and was positive in 9 additional cases not detected by hysteroscopy. Chronic endometritis at histology was found in approximately 30% of infertile women and 35% of cases related to abnormal uterine bleeding. The sensitivity, specificity, and positive and negative predictive values of hysteroscopy for chronic endometritis based on detection of only hyperemia and edema were 91.8%, 92.9%, 63.9%, and 98.8%, respectively; the diagnostic accuracy was 92.7 %. The combination of hyperemia, edema, and micropolyps had sensitivity, specificity, and positive and negative predictive values of 55.4%, 99.9%, 98.4%, 94.5%, respectively, with a diagnostic accuracy of 93.4%. CONCLUSIONS: Fluid hysteroscopy is very reliable in diagnosing no inflammation, while detection of micropolyps is a very reliable sign of inflammation. When performing hysteroscopy for abnormal uterine bleeding or infertility, signs of chronic endometritis should always be sought.  相似文献   
997.
The mediastinal vessels in 27 patients who had previously undergone vascular surgery were evaluated with use of magnetic resonance (MR) imaging for patency and the presence of stenosis. Thirty-six postoperative vessels or shunts were studied, including 11 aortas after coarctation or stenosis repair, 18 systemic-pulmonary shunts, four pulmonary artery or vein repairs, and three spiral vein grafts. Angiographic (n = 21), direct surgical (n = 1), contrast material-enhanced computed tomography (n = 1), or clinical (n = 13) findings were correlated with the MR findings. Overall, the accuracy of MR imaging for determination of patency was 100%. In patients with angiographic correlation and technically adequate MR examinations, MR imaging results were used to identify or exclude stenoses correctly in 66.7% of patent vessels. The four missed or underestimated stenoses occurred in vessels 10 mm or less in diameter.  相似文献   
998.
Untreated neoplasms of the neck (tumors of the oropharynx, supraglottic area, carotid body, and thyroid, in addition to malignant lymphadenopathy) were evaluated in 23 patients with magnetic resonance (MR) imaging. The results were compared with computed tomographic (CT) scans in 20 patients. Contrast between tumor and fat was best on relatively T1-weighted images (500/30-35 [TR msec/TE msec]), whereas separation of tumor and muscle was best with relatively T2-weighted pulse sequences (1,500/90). Balanced images (1,500/30-35) provided best overall image quality and best demonstrated vascular anatomy. MR imaging was usually superior to CT in showing the relationship of tumor mass to muscle. MR imaging and contrast material-enhanced CT were equivalent in most patients in defining vascular anatomy, but MR imaging was superior when intravenous contrast material was not administered. However, CT was more helpful in showing bone and cartilage anatomy, and in some patients CT also was better in showing airway abnormalities. Despite these limitations, MR imaging is a promising imaging technique for studying neoplasms of the neck.  相似文献   
999.
1000.
Although the secondary transmission of hepatitis A virus (HAV) infection is preventable through vaccination, it is not known whether the vaccination of household contacts is feasible. To this end, we conducted a prospective cohort study among the household contacts, 40 years of age or less, of all persons infected with primary HAV infection (index cases) and admitted to eight hospitals in southern Italy within 7 days of onset. Household contacts were vaccinated, and serum samples were taken at vaccination and after 14 and 45 days. Secondary cases were defined as those with IgM seroconversion occurring at least two weeks after enrollment. Coprimary cases were those assumed to have had the same exposure as the index case. Susceptible cases were those who were negative for both IgG and IgM. A total of 495 household contacts participated (acceptance rate of 65%); 65% were vaccinated within 4 days of admission of the index case and 95% within 7 days. At enrollment, 196 (39.6%) household contacts were immune (IgG-positive serum). During follow-up, 19 (3.8%) were IgM-positive: 13 (2.6%) were coprimary cases and 6 (1.2%; 95% CI: 0.2-3.2) secondary cases (5 identified at 14 days from vaccination and 1 at 45 days). Of the 241 susceptible cases, 192 (79.7%) had developed IgG antibodies at 14 days and only 3 (1.2%) did not develop IgG antibodies at 45 days. The 65% acceptance rate and the finding that 95% of the participating household contacts were vaccinated within 7 days of the index case's hospitalization indicate that timely vaccination is indeed feasible. The necessity of returning for the collection of blood samples probably decreased the acceptance rate.  相似文献   
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