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71.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.  相似文献   
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73.
Abstract: Adenosine plays an important neuromodulatory role in the central nervous system, and adenosine deaminase is an important enzyme in the degradation of adenine nucleotides. Methylmercury is the most prevalent form of mercury found in the environment. Methylmercury neurotoxicity has been correlated to the production of reactive oxygen species. In this study, its potential pathogenic effects were investigated in vitro in cerebral cortex and hippocampus of rats. We first observed that adenosine deaminase activity was higher in young rat brains when compared to the 60‐day‐old rats and was higher in hippocampus when compared to the cortex. Methylmercury (0.1, 1.0, 20 µM) inhibited adenosine deaminase activity in 7‐ and 60‐day‐old rats in a concentration‐dependent manner. We have demonstrated that methylmercury‐induced inhibition was antagonized by garlic alcoholic extract, but sodium selenate did not alter enzyme activity. In addition, glutathione and dithiothreitol restored the methylmercury‐induced decrease of adenosine deaminase activity. These results demonstrated that there are age‐related changes in adenosine deaminase activity and that thiol agents may contribute to the maintenance of adenosine deaminase activity and may be important in the neuromodulation of adenosine. Garlic alcoholic extract may be effective in reducing the effect of methylmercury‐induced adenosine deaminase, which may be due to its sulphur‐containing compounds.  相似文献   
74.
OBJECTIVE: Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities, in the platelets and serum, were examined in patients with uterine cervix neoplasia without treatment as well as in patients treated by conization or radiotherapy (RTX). DESIGN AND METHODS: The patients were divided based on the amount of time from the end of the treatments until the day of the blood sampling. Groups I (n=19) (conization) and III (n=11) (radiotherapy) (treated from one to five years earlier), groups II (n=19) (conization) and IV (n=16) (radiotherapy) (treated recently; up to three months earlier) and the non-treated group (cancer) (n=7). RESULTS: E-NPP and ADA in the platelets and E-NPP in the serum were decreased in all the treated groups in relation to the control and non-treated groups, while ADA in the serum was decreased only in the conization groups in relation to them. In group II, E-NPP and ADA, in the platelets, were increased in relation to group IV. CONCLUSION: The tendency of reduction for E-NPP and ADA indicates that they may act together to control nucleotide levels and it may also be speculated that surgery causes greater platelet activation contributing to the changes seen in the conization groups. In this sense, platelets seem to be more sensitive than serum.  相似文献   
75.
Cobalt is known to be toxic at high concentration, to induce contact dermatosis, and occupational radiation skin damage because of its use in nuclear industry. We investigated the intracellular distribution of cobalt in HaCaT human keratinocytes as a model of skin cells, and its interaction with endogenous trace elements. Direct micro-chemical imaging based on ion beam techniques was applied to determine the quantitative distribution of cobalt in HaCaT cells. In addition, synchrotron radiation X-ray fluorescence microanalysis in tomography mode was performed, for the first time on a single cell, to determine the 3D intracellular distribution of cobalt. Results obtained with these micro-chemical techniques were compared to a more classical method based on cellular fractionation followed by inductively coupled plasma atomic emission spectrometry (ICP-AES) measurements. Cobalt was found to accumulate in the cell nucleus and in perinuclear structures indicating the possible direct interaction with genomic DNA, and nuclear proteins. The perinuclear accumulation in the cytosol suggests that cobalt could be stored in the endoplasmic reticulum or the Golgi apparatus. The multi-elemental analysis revealed that cobalt exposure significantly decreased magnesium and zinc content, with a likely competition of cobalt for magnesium and zinc binding sites in proteins. Overall, these data suggest a multiform toxicity of cobalt related to interactions with genomic DNA and nuclear proteins, and to the alteration of zinc and magnesium homeostasis.  相似文献   
76.
STUDY DESIGN: Original article. OBJECTIVE: To test the use of bornaprine in the hyperhidrosis treatment in the acute phase of spinal cord-injured patients. SETTING: Patients with acute spinal cord lesions in the Spinal Unit of Pietra Ligure, Savona, Italy. METHOD: In 4 years, 12 patients have been treated, for a maximum period of 75 days, with dosages ranging from 2 to 4 mg day(-1). RESULTS: All of them reported long-lasting subjective benefits, without side effects, even after the interruption of the therapy. CONCLUSION: The bornaprine treatment, at 2 or 4 mg day(-1) dosage, has been effective and safe to contrast hyperhidrosis, in the acute phase of spinal cord-injured patients. This positive experience would require additional trials and a larger number of cases to gain a more solid support.  相似文献   
77.
Premature ovarian failure occurs in approximately 1:1000 women before 30 years, 1:250 by 35 years and 1:100 by the age of 40. It is characterized by primary or secondary amenorrhea and cannot be considered as definitive because spontaneous conception may occur in 5 to 10% of cases. In 95% of cases, premature ovarian failure is sporadic. The known causes of premature ovarian failure include chromosomal defects, autoimmune diseases, exposure to radiation or chemotherapy, surgical procedures, and certain drugs. Frequently, however, the etiology is not clear and these cases are considered to be idiopathic. Premature ovarian failure is defined by gonadal failure and high serum follicle-stimulating hormone (FSH) levels. Clinical approach includes emotional support, hormonal therapy with estrogens and progesterone or progestogens, infertility treatment, and prevention of osteoporosis and potential cardiovascular risk.  相似文献   
78.
Since a number of patients with Parkinson’s Disease (PD) complain of painful sensations, we studied whether the central processing of nociceptive inputs is abnormal in PD. To test this hypothesis, we recorded scalp CO2 laser evoked potentials (LEPs) to hand skin stimulation in 18 pain-free PD patients with unilateral bradykinetic-rigid syndrome (hemiparkinson) during the off state and in 18 healthy subjects. This technique allows us to explore non-invasively the functional status of some cerebral structures involved in nociceptive input processing. In both PD patients and control subjects, CO2 laser stimulation gave rise to a main negative N2 potential followed by a positive P2 response at vertex peaking at a latency of about 200 and 300 ms, respectively. These potentials are thought to originate from several brain structures devoted to nociceptive input processing, including the cingulate gyrus and insula. PD patients and normal subjects showed comparable N2 and P2 latencies, whereas the N2/P2 peak-to-peak amplitude was significantly lower in PD patients (regardless of the clinically affected body side) than in controls. LEPs were even recorded after acute L-dopa administration in 7 additional PD patients. L-dopa administration yielded no significant change in N2/P2 amplitude as compared to the off state. These results suggest an abnormal nociceptive input processing in pain-free PD patients which appears to be independent of clinical expression of parkinsonian motor signs and is not affected by dopaminergic stimulation.  相似文献   
79.
80.

INTRODUCTION

Diagnostic errors in orthopaedics are usually caused by missing a fracture or misreading radiographs. The aim of this study was to document the pick-up rate of the wrong diagnoses by reviewing X-rays and casualty notes in the next-day trauma meeting.

PATIENTS AND METHODS

The casualty notes and radiographs of 503 patients were prospectively reviewed in the daily trauma meeting between August 2002 and December 2002 in a district general hospital. The relevant data were collected and analysed by a single assessor.

RESULTS

The false positive rate for making an orthopaedic diagnosis was 12.6% (i.e.) diagnosing a fracture, when none existed). The false negative (missing) rate was 4%, while 2.4% incidental findings were missed, or at least not documented, after reading the X-rays. There were 7.8% wrong diagnoses made. The majority of the patients were seen by the senior house officers.

CONCLUSIONS

The medicolegal significance of false negative diagnosis is obviously greater. In a busy emergency department, where a large number of patients are seen, there is a greater risk. This study shows the importance in a small-to-medium sized accident and emergency unit as well, where there is no senior cover available out-of-hours for final radiological interpretation. A morning trauma meeting which covers reviewing admitted patients as well as non-admission orthopaedic referrals has an effective risk management solution to early detection of missed and wrong diagnoses.  相似文献   
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