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1.
Activation of the ras oncogene is associated with overproduction of the normal gene product (p21). Ninety one paraffin-embedded specimens were used to map the distribution of the normal form of p21 in normal, inflamed, cirrhotic and carcinomatous liver parenchyma. Monoclonal antibodies (Mo-RAP) were raised against the normal form of the ras-oncogene product and histological sections were stained by the peroxidase-antiperoxidase technique. Normal, inflamed and cirrhotic liver showed either minimal or moderate cytoplasmic staining. By contrast primary (n = 13) and secondary (n = 41) liver carcinomas exhibited intense staining. The differential pattern observed in p21 distribution could have useful clinical applications. 相似文献
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Ronald B. George Abigail H. Melnick Erin C. Rose Ashraf S. Habib 《Journal canadien d'anesthésie》2007,54(3):218-222
PURPOSE: To report the use of regional anesthesia and iv nitroglycerin to provide anesthesia and uterine relaxation for three Cesarean deliveries (CD) involving ex utero intrapartum treatment (EXIT) of potentially life-threatening airway obstruction in the newborn. CLINICAL FEATURES: Case 1--a 36-yr-old woman at 38 weeks' gestation was scheduled for an elective CD for fetal skeletal dysplasia and micrognathia. Case 2--a 34-yr-old woman at 35 weeks gestation had a fetal ultrasound revealing fixed neck flexion and micrognathia consistent with fetal arthrogryposis. Case 3--a 27-yr-old woman presented at 38 weeks gestation for CD for severe fetal micrognathia, with mandibular growth below the fifth percentile. For each case, a combined spinal epidural anesthetic was performed with 0.75% bupivacaine, fentanyl and morphine intrathecally followed by placement of a multiorifice epidural catheter. Prior to uterine incision patients received a loading dose followed by an iv infusion of nitroglycerin. Uterine relaxation was sufficient in all cases for delivery of the fetus, and allowed for evaluation by direct laryngoscopy and intubation while maintaining fetal-placental circulation. The surgical procedures were completed without incident. CONCLUSIONS: Anesthesia and uterine relaxation for CD and EXIT procedures can be safely provided with regional anesthesia and iv nitroglycerin. 相似文献
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Awoniyi O. Awonuga Nicola Dean Jamal Zaidi Rudiger U. Pittrof Jinan S. Bekir Seang-Lin Tan 《Journal of assisted reproduction and genetics》1996,13(4):293-297
Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome.
Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle.
Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%).
Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society. 相似文献
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K A Gershman R T Rolfs S A Larsen A Zaidi N A Palafox 《International journal of epidemiology》1992,21(3):599-606
The annual numbers of reported cases of syphilis in the Republic of the Marshall Islands (RMI) increased from none in 1983 to more than 600 in 1989, suggesting a large outbreak of syphilis. Much of the increase resulted from expanded serological screening. The apparent outbreak of syphilis, therefore, may have been partly the result of increased surveillance or, since the RMI was formerly a yaws endemic area, possibly due to a resurgence of yaws. To address this problem and better characterize the epidemic, we analysed results from a 1989/90 Ministry of Health Services mass serological screening on Majuro Atoll, the main population centre. Serum specimens from 9160 people (86% of residents aged 15-44 years) on Majuro were screened with the rapid plasma reagin (RPR) card test; we repeated the RPR and performed a confirmatory microhaemagglutination assay for Treponema pallidum-specific antibodies (MHA-TP) on a sample of serum specimens. To estimate the seroprevalence of syphilis, we also tested a sample of RPR nonreactive specimens by MHA-TP. Among people less than 45 years of age, total (11.5%) and high-titre (5.2%) seropositivity rates were highest in the 20-24 year age group, as was MHA-TP seroprevalence (15.9%). These results suggested that a large outbreak of syphilis was responsible for the observed seroreactivity. Cumulative incidence modelling and comparisons with the results of a previous serosurvey conducted in 1985 suggested that the duration of the syphilis epidemic was approximately 10 years and that incidence had not increased appreciably since 1985. 相似文献
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M. F. Gagnadoux J. L. Bacri M. Broyer R. Habib 《Pediatric nephrology (Berlin, Germany)》1989,3(1):50-55
Over a 15-year period we observed seven children (four girls, three boys) who presented within the first months of life with severe renal failure and acidosis, associated with hypertension in five patients and polyuria in four. In addition, one patient had a severe cholestatic liver disease. In two families, a similarly affected sibling had died previously. Four patients were referred with the clinical diagnosis of polycystic kidney disease because of moderate enlargement of kidneys, but renal imaging (intravenous pyelography and ultrasonography) did not confirm this diagnosis. A renal biopsy, performed in all patients, showed similar features characterized by a diffuse chronic tubulo-interstitial nephritis (TIN) and particularly by the presence of microcystic dilatation of proximal tubules and Bowman's space. Liver pathology was normal in two patients, including one with hepatomegaly. However, in the patient with cholestasis there was inflammatory portal fibrosis with mild duct proliferation. Progression of the renal disease was extremely rapid and all patients reached end-stage renal failure (ESRF) before the age of 2 years (11–22 months). Two children had successful renal transplants. Although this chronic TIN shares some features with nephronophthisis, we suggest that it represents a distinct entity both on clinical and morphological grounds. The specific clinical features of this disease are its early onset and rapid progression to ESRF. Pathologically, it differs from nephronophthisis by the absence of medullary cysts and thickened tubular basement membranes and by the presence of cortical microcysts. 相似文献
9.
Gall bladder hydatid cyst is a rare entity. Concurrent occurrence of gall blader hydatid cysts along with liver cysts, especially with the biliary channels clear of cysts, is very rare. We report a 27-year-old man with a gall bladder hydatid cyst that was diagnosed only after opening the resected specimen of the gall bladder. 相似文献
10.
Osteoclastic inhibition: an action of nitric oxide not mediated by cyclic GMP. 总被引:18,自引:3,他引:15 下载免费PDF全文
I MacIntyre M Zaidi A S Alam H K Datta B S Moonga P S Lidbury M Hecker J R Vane 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(7):2936-2940
The osteoclast is unique in its ability to resorb bone, and excessive osteoclastic activity has been implicated in osteoporosis, Paget disease of bone, rheumatoid arthritis, and the growth of metastases in bone. The activity of this cell is controlled by the main circulating inhibitor, calcitonin, in association with locally produced modulators. We show that nitric oxide (NO) may be an important member of the latter group. NO is produced by the vascular endothelium and nervous system and is involved in both neurotransmission and the regulation of blood pressure. However, our results show that the autocoid is also a potent inhibitor of osteoclast function. NO (30 microM) produced a decrease to approximately 50% of the original osteoclast spread area. Similar effects were also produced by 3-morpholinosydnonimine or sodium nitroprusside, reagents that spontaneously release NO. These shape changes were associated with a reduction of bone resorption after a 24-hr incubation of isolated osteoclasts on devitalized bone slices. NO is thought to act by stimulating guanylate cyclase, with a consequent increase in cyclic GMP, but a different mode of action is likely in the osteoclast since dibutyryl or 8-bromo cyclic GMP have no effect. It should be noted that calcitonin can produce similar changes in shape and activity but is associated with an increase in osteoclast intracellular calcium and cessation of membrane movement; neither of these is produced by NO, suggesting that its mode of action is different. The abundance of NO-producing endothelial cells in bone marrow and their proximity to osteoclasts suggests that marrow endothelial cells may play a physiological role in the regulation of osteoclastic activity. 相似文献