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21.
Value of antenatal echocardiography in high risk patients to diagnose congenital cardiac defects in fetus 总被引:3,自引:0,他引:3
Results of fetal echocardiography in 1062 high risk pregnant patients are described. It was performed before 28 weeks of gestation
in 770 cases. These were 38 abnormal scans (3.6%). A fetal arrhythmia was diagnosed in 14 cases and structural abnormality
of the heart in 24. Complete atrioventricular block was commonest (n=12), structural heart disease associated in two of these
cases. Other lesions identified were atrioventricular septal defect (n=5), hypoplastic left heart syndrome (n=4), ventricular
septal defect (n=4), Ebstein’s anomaly (n=3), coarctation of aorta (n=2) and others (n=9). Postnatal confirmatory echocardiography
is available in a total of 993 babies including 36 of 38 abnormal cases. There were eleven neonatal deaths amongst babies
with abnormal scans. Errors in interpretation were observed in six instances. An anomaly was missed in five cases; in two
of these, the main cardiac malformation was picked up but secondary lesions were missed. In one case, a false positive diagnosis
of atrial septal defect was made. These errors did not influence the management of the pregnancy.
Fetal echocardiography is a very sensitive (91.6%) and specific (99.9%) tool for antenatal diagnosis of congenital heart disease
in high risk pregnancies. The information so obtained helps in guiding the optimal obstetric and neonatal management of these
cases. 相似文献
22.
Shyam K Penketh PG Shapiro M Belcourt MF Loomis RH Rockwell S Sartorelli AC 《Journal of medicinal chemistry》1999,42(5):941-946
Some 4- and 2-(nitrobenzyloxycarbonyl)-1, 2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines (4, 6, and 7) were synthesized and evaluated for their ability to exert preferential toxicity to hypoxic EMT6 mammary carcinoma cells using a colony-forming assay. Of these, the 4,5-dimethoxy-2-nitro analogue 6 (50 microM, 1-h exposure) caused greater than 3 logs of kill of hypoxic cells, with relatively minor toxicity to corresponding aerobic cells. The ability of 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues to reach and kill hypoxic cells of solid tumors was also demonstrated using intradermally implanted EMT6 solid tumors in mice. In addition, a possible source of toxicity to normal tissue, i. e., the activation of the 4-nitrobenzyl derivative 4 by glutathione S-transferase-catalyzed thiolysis, was essentially eliminated by replacing one of the benzylic methylene protons by a methyl group. The 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues also appear to be reduced more easily under acidic conditions (pH 6.0) than under neutral conditions, as measured by differential pulse polarography. Since the pH in hypoxic regions is often lower than that in adjacent aerobic regions, this property should aid in the cytotoxic action of these agents against hypoxic cells of solid tumors. 相似文献
23.
Julia Redburn Sudha Sundar M Usherwood Monica Roche 《Journal of obstetrics and gynaecology》2004,24(5):552-556
This study aims to assess trends in compliance with current colposcopy guidelines in 10 gynaecological units in four English counties since 1996; to identify constraints on compliance and suggest change in practice. All 10 gynaecology units in Oxfordshire, Buckinghamshire, Northamptonshire and Berkshire participated. Data were collected prospectively by colposcopists from 23,500 new referrals across a 55-month period from September 1996 to March 2001. The Oxford Cancer Intelligence Unit performed collation, quality assurance and retrieval of data for incomplete records. Audit results were disseminated annually to colposcopists via the Regional Colposcopy Group. Colposcopy waiting times exceeded the standards, but waiting times for high-grade referrals showed statistically significant improvement. Six standards were achieved; relating to accuracy, appropriateness of management and outcomes. The seven unmet standards relate to waiting times, colposcopist's caseload, follow-up policy and the proportion of cervical epithelial neoplasia (CIN) on histology. Changes in practice are suggested, constraints on compliance are identified and the appropriateness of some guidelines is questioned. 相似文献
24.
Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope
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Divya Karuppannasamy Andavar Raghuram Devisundaram Sundar 《Indian journal of ophthalmology》2014,62(4):497-500
Many systemic antimicrobials have been implicated to cause ocular adverse effects. This is especially relevant in multidrug therapy where more than one drug can cause a similar ocular adverse effect. We describe a case of progressive loss of vision associated with linezolid therapy. A 45-year-old male patient who was on treatment with multiple second-line anti-tuberculous drugs including linezolid and ethambutol for extensively drug-resistant tuberculosis (XDR-TB) presented to us with painless progressive loss of vision in both eyes. Color vision was defective and fundus examination revealed optic disc edema in both eyes. Ethambutol-induced toxic optic neuropathy was suspected and tablet ethambutol was withdrawn. Deterioration of vision occurred despite withdrawal of ethambutol. Discontinuation of linezolid resulted in marked improvement of vision. Our report emphasizes the need for monitoring of visual function in patients on long-term linezolid treatment. 相似文献
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Colorectal cancer (CRC) is a frequently diagnosed cancer and causing significant mortality in the patients. Metastasis caused by CRC is mainly responsible for this cancer-related deaths. Despite recent advancements in the treatment methods, prognosis remains poor. Therefore, effective treatment strategies need to be designed for successful management of this disease. Dehydroepiandrostenedione (DHEA), a 17-ketosteroid hormone produced by adrenal glands, gonads and including gastrointestinal tract is required for several physiological processes. Deregulation of DHEA levels leads to various disease conditions including cancer. In fact, several experimental studies strongly suggest that DHEA could be used as a chemopreventive agent against colon cancer. Prenlyation of certain membrane proteins such as phosphatase of regenerating liver-3 (PRL-3) is crucial for metastatic progression of colon cancer cells. The ability of DHEA to target prenylation pathway could be utilized to inhibit PRL-3 prenylation for successful prevention of CRC metastases. As DHEA is a widely consumed drug for various ailments, incorporation of DHEA in the treatment regimen may be beneficial to prevent or delay the occurrence of metastasis resulting from CRC. 相似文献