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41.
Placental protein 13 (PP13) is a galectin expressed by the syncytiotrophoblast. Women who subsequently develop preterm pre-eclampsia have low first trimester maternal serum PP13 concentrations. This study revealed that third trimester maternal serum PP13 concentration increased with gestational age in normal pregnancies (p < 0.0001), and it was significantly higher in women presenting with preterm pre-eclampsia (p = 0.02) and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome (p = 0.01) than in preterm controls. Conversely, placental PP13 mRNA (p = 0.03) and protein, as well as cytoplasmic PP13 staining of the syncytiotrophoblast (p < 0.05) was decreased in these pathological pregnancies compared to controls. No differences in placental expression and serum concentrations of PP13 were found at term between patients with pre-eclampsia and control women. In contrast, the immunoreactivity of the syncytiotrophoblast microvillous membrane was stronger in both term and preterm pre-eclampsia and HELLP syndrome than in controls. Moreover, large syncytial cytoplasm protrusions, membrane blebs and shed microparticles strongly stained for PP13 in pre-eclampsia and HELLP syndrome. In conclusion, parallel to its decreased placental expression, an augmented membrane shedding of PP13 contributes to the increased third trimester maternal serum PP13 concentrations in women with preterm pre-eclampsia and HELLP syndrome.  相似文献   
42.
Studies were conducted to evaluate the potential cause for release of covalently bound Staphylococcal protein A (SpA) from a silica based extracorporeal immunoadsorbent matrix. In vitro tests revealed that SpA could be detected in human plasma, human serum, and chicken serum upon exposure to the immunoadsorbent matrix which had been treated to remove non-covalently bound SpA. In contrast, only minute quantities of SpA were detected after exposure of a physiologic mixture of purified albumin and immunoglobulin G (IgG) to the immunoadsorbent matrix. Additional tests, employing a cocktail of protease inhibitors and formalin as a general stabilizer and protease inhibitor, revealed significant inhibition of endogenous proteolytic activity present in plasma and serum. Prevention of this proteolytic activity also significantly inhibited the release of covalently bound SpA from the immunoadsorbent matrix upon contact with plasma or serum samples. Further analyses of serum samples from patients with immune thrombocytopenia, chemotherapy associated thrombotic thrombocytopenic purpura-hemolytic uremic syndrome, and breast cancer revealed a lack of association between the quantity of SpA proteolytically released and observed clinical responses or adverse effects experienced during immunoadsorption treatments. These studies indicate that SpA detected in plasma or serum after exposure to the immunoadsorbent is due to inherent endogenous proteolytic activity which cleaves protein fragments from the matrix and that these cleaved SpA fragments do not appear to contribute to the observed clinical responses or adverse effects in treated patients.  相似文献   
43.
OBJECTIVE: To examine birth weight related risks of fetal injury in connection with shoulder dystocia. STUDY DESIGN: The investigation was based on a retrospective analysis of 316 fetal neurological injuries associated with deliveries complicated by arrest of the shoulders that occurred across the United States. RESULTS: The study revealed that the distribution of birthweights for the high risk shoulder dystocia population differs from the standard birthweight distribution. The relative difference per birthweight interval is used to adjust an assumed 1:1000 baseline risk of injury due to shoulder dystocia following vaginal deliveries. These adjusted risks show a need to consider new thresholds for elective cesarean delivery. CONCLUSIONS: Current North American and British guidelines, that set 5000 g as minimum estimated fetal weight limit for elective cesarean section in non-diabetic and 4500 g for diabetic gravidas, may expose some macrosomic fetuses to a high risk of permanent neurological damage. The authors present the opinion that the mother, having been informed of the risks of vaginal versus abdominal delivery, should be allowed to play an active role in the critical management decisions.  相似文献   
44.
On the basis of 333 documented cases of permanent perinatal neurological damage, associated with arrest of the shoulders at birth, the authors conducted a retrospective study in order to evaluate the predisposing role, if any, of the utilization of extraction instruments. The investigation revealed that 35% of all injuries occurred in neonates delivered by forceps, ventouse or sequential ventouse–forceps procedures. This frequency was several-fold higher than the prevailing instrument use in the practices of American obstetricians during the same years. A high rate of forceps and ventouse extractions was demonstrable in all birth weight categories. Average weight and moderately large for gestational age fetuses underwent instrumental extractions more often than grossly macrosomic ones. This circumstance indicates that forceps and ventouse are independent risk factors, unrelated to fetal size. Their use entailed central nervous system injuries significantly more often than did spontaneous deliveries. The findings suggest that extraction procedures may be as important as macrosomia among the factors that lead to neurological damage in the child in connection with shoulder dystocia. Because they augment the intrinsic dangers of excessive fetal size exponentially, the authors consider their use in case of ≥4,000 g estimated fetal weight inadvisable. Sequential forceps–ventouse utilization further doubles the risks and is, therefore, to be avoided in all circumstances.  相似文献   
45.
Amyloid involvement of the breast is infrequently reported and may have clinical and radiological features suspicious for a primary breast malignancy. We describe a case of amyloid of the breast in which asymptomatic mammographic findings were suspicious for locally recurrent disease in a patient with previously treated breast cancer.  相似文献   
46.
OBJECTIVE: To demonstrate the use of high resolution ultrasound measurements and power Doppler mode in the diagnosis and follow up of a patient with psoriatic arthritic with retrocalcaneal bursitis and Achilles tendonitis. METHODS: An outpatient based ATL HDI 3000 ultrasound equipment was used with a CL10-5 MHZ 26 mm probe and musculoskeletal software. Real time B mode and power Doppler mode were used to detect changes in structure and blood flow. RESULTS: Unilateral retrocalcaneal bursitis and Achilles tendonitis were demonstrated by sonography. Power Doppler mode was useful to demonstrate an increased blood flow around an abnormal retrocalcaneal bursa. A follow up examination showed marginal thickening of the Achilles tendon without any bursitis. CONCLUSIONS: Ultrasonography is an objective method in the confirmation of clinical diagnosis after physical examination. During the examination it is possible to gain not only qualitative but also quantitative data. A comparative study with quantitative data is possible in longitudinal studies.  相似文献   
47.
SIR, Behçet's disease is a chronic, relapsing inflammatorydisorder that causes ocular inflammation in up to 70% of patients[1, 2]. Despite intensive immunosuppressive therapy, relapsingocular inflammation can lead to permanent loss of vision [2].Infliximab, a monoclonal chimeric antibody to tumour necrosisfactor (TNF), is a novel therapy used in the management of Behçet'spanuveitis that is unresponsive to established immunosuppressivetreatment. Initialshort-term experience in six patients withBehçet's panuveitis has resulted in a rapid and effectiveresolution of ocular inflammation with no side-effects [3, 4].Long-term safety data obtained in patients taking infliximabfor rheumatoid arthritis (RA) and Crohn's disease report an  相似文献   
48.
49.
During the last twenty-year period therapeutic plasma exchange (TPE) was used in the treatment of 68 patients with myasthenia gravis and 61 patients with multiple sclerosis. The therapeutic effects were evaluated on the basis of neurologic deficit changes, electrophysiological findings, necessary laboratory analyses and patient's general conditions. It was shown that the therapeutic effects mosty depended on the nature and stage of the basic disease, adequate selection of the patients and timely applied therapeutic procedure. Significant positive effects of the TPE treatment applied with the anti-inflammatory and immunosuppressive therapy were observed in patients with myasthenia gravis and multiple sclerosis upon clinical findings and some paraclinical tests.  相似文献   
50.
Oral tacrolimus treatment of severe colitis in children   总被引:5,自引:0,他引:5  
OBJECTIVE: To evaluate the efficacy of oral tacrolimus as an induction agent in steroid-refractory severe colitis. STUDY DESIGN: Open-label, multicenter trial of oral tacrolimus in patients with severe colitis. Patients not responding to conventional therapy received tacrolimus, 0.1 mg/kg/dose given twice a day, and the dosage was adjusted to achieve blood levels between 10 and 15 ng/mL. Response was defined as improvement in a number of clinical parameters (including abdominal pain, diarrhea, rectal bleeding, and cessation of transfusions). Patients who responded by 14 days continued to receive tacrolimus, and 6-mercaptopurine or azathioprine was added as a steroid-sparing agent 4 to 6 weeks after the tacrolimus was instituted. RESULTS: Fourteen patients were enrolled in the study. One patient elected to withdraw after 48 hours. Of the 13 remaining, 9 (69%) responded and were discharged. Tacrolimus was continued for 2 to 3 months in the responders, except for 1 patient who was given tacrolimus for 11 months. After 1 year of follow-up, only 5 (38%) patients were receiving maintenance therapy; the other 4 responders had undergone colectomy. CONCLUSION: Although tacrolimus is effective induction therapy for severe ulcerative or Crohn's colitis, fewer than 50% of patients treated will successfully achieve a long-term remission.  相似文献   
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