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101.
Cerebral angiography was performed in 34 children having sudden hemiplegia of obscure orgin. Arterial occlusions were detected in 61.7%. Occlusions were seen more often in cases where angiography was done early in the course of illness. The involvement of internal carotid artery with middle cerebral artery and/or anterior cerebral artery was most common. Arteritis was the suggested etiology of occlusion.  相似文献   
102.
Use of alcoholic beverages increases risk of cancer at several target sites, including the breast. Of several possible mechanisms for this effect, competitive inhibition by ethanol of hepatic clearance of nitrosamines, resulting in increased dose delivery to posthepatic tissues, gives the quantitatively most pronounced enhancement. We investigated whether this effect would pertain to the mammary gland, and to ethanol and nitrosamines delivered translactationally to sucklings. Ethanol (1.6 g/kg) was administered by gavage to nursing Sprague-Dawley rats 10 min before 5 mg/kg N-nitrosodimethylamine (NDMA) or 50 mg/kg 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK); treatment was on postnatal days 1, 7, or 14. Tissues taken 4 h later for analysis of O(6)-methylguanine in DNA were liver, blood, and mammary glands from the mothers, and liver, lung, kidney, and blood from the sucklings. Ethanol cotreatment resulted in a marked, 10-fold increase in O(6)-methylguanine adducts from NDMA in mammary gland, as well as smaller but significant increases in this tissue from NNK and in maternal blood cells from both chemicals; adducts in maternal liver decreased slightly. In the sucklings, ethanol cotreatment also lowered adducts in liver after NDMA or NNK treatment. After NDMA, adducts were also detected in suckling lung and kidney and were increased five- to 10-fold after ethanol coexposure. Adducts from either chemical, with or without ethanol, decreased markedly in all suckling tissues with development from postnatal day 1 to day 14. Thus ethanol coexposure with nitrosamines increases O(6)-methylguanine DNA adducts in mammary gland and strongly influences adduct formation in suckling tissues after translactational delivery.  相似文献   
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Currently used temperature sensor systems do not provide sufficient spatial resolution and can not be used as an integrated part of minimally invasive treatment. Few magnetic resonance (MR) compatible sensor systems are available. A distributed fibre Bragg-grating sensor system for use in biological tissue was constructed. Ten Bragg gratings were inscribed in the core of an optical fibre. The fibre was mounted into tubes made of MR-compatible materials. An opto-electronic unit connected to the fibre was used for signal generation and detection. Communication with a PC allowed presentation and logging of temperature data. The system was calibrated to the temperature range ‘195.8°C to 100°C. Experiments were conducted during freezing (cryoablation) of porcine liver in vivo. The system yielded a temperature profile with 6.5 mm spatial resolution and 5 s temporal resolution. Both mechanical stability and MR compatibility were acceptable and will allow routine use.  相似文献   
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We present a clinical study of 204 cases of obstructed labour admitted over a period of 5 years between 1991-92 and 1996-97 in a rural institute in central India. They constituted 1.9% of births. Seventy-one per cent of the cases were from the rural area (similar to the overall patient population in this hospital), 31.4% women were primigravidae. Of the subjects, 64.7% were between 20 and 29 years. Malpresentation was the cause in 53.2%, followed by cephalopelvic disproportion, in 41.1%. Intraoperative incomplete rupture was detected in 5.9% cases. The commonest maternal morbidity was intraoperative extension of uterine incision at the time of caesarean section, mostly lateral (14.0%). Of the women, 12.5% had intrapartum or postpartum sepsis. The perinatal mortality was 160/1000. There was no maternal mortality. Timely diagnosis of malpresentation, pelvic contraction and use of a partogram at all levels could have prevented obstructed labour. In these unfortunate situations, judicious selection of subjects for caesarean section is appropriate, avoiding heroic vaginal procedures even with a dead baby. Infection devitalises tissues and attempts at vaginal delivery may be dangerous.  相似文献   
107.
Peripheral blood leukocyte counts were performed in 167 children with acute otitis media who underwent myringotomy with culture of the middle ear exudate. A markedly elevated (greater than 97th percentile for age) leukocyte count was noted at initial presentation among 28% of these children, and counts exceeded 20,000/microL among 9%. Children older than six years were more likely than younger children to have marked leukocyte (41 v 24%, P less than 0.1). Children with culture-positive and culture-negative acute otitis media had similar leukocyte counts. There was no difference in frequency of posttreatment leukocytosis between those children who had complete resolution of acute otitis media and those children who had persistent otitis media with effusion. At follow-up 10 to 14 days later, relative leukopenia was observed significantly more often than at initial presentation (13 v 2%, P less than 0.001), and was most common among children two to five years old. Absolute neutropenia was likewise more common at the follow-up than at initial presentation (10 v 2%, P less than 0.01). Children treated with the fixed combination of erythromycin ethyl succinate-sulfisoxazole acetyl were somewhat more likely to have absolute neutropenia than those children who were treated with amoxicillin, but this difference was not statistically significant (14 v 6%, P less than 0.1). Acute otitis media, and perhaps the specific antibiotic therapy prescribed for acute otitis media, may exert marked effects upon peripheral blood counts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
108.
Seventy-seven Angiosperms (Euphorbiaceae to Menispermaceae) are listed, which are used by traditional healers in five regions of Eastern Tanzania; namely, Coast, Dar es Salaam, Kilimanjaro, Morogoro and Tanga. For each species listed, the botanical name, vernacular name, collection number, locality, habit, distribution and medicinal uses are given. Additionally, information from the literature on medicinal uses, chemical constituents and pharmacological effects is also provided.  相似文献   
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Aim  To investigate the attitudes of final year dental students in Wales and Ireland to the use of rubber dam.
Methods  A pre-piloted questionnaire was distributed to final year dental students in Cardiff and Cork Dental Schools in January 2008. Information sought included attitudes to, and the current and anticipated use of, rubber dam for a variety of operative and endodontic treatments.
Results  Of 93 questionnaires distributed, 87 were completed and returned (response rate = 94%; Cardiff: 89%, n  = 51; Cork: 100%, n  = 36). Rubber dam was routinely used by 98% of respondents ( n  = 85) on adult patients, but only 32% of respondents ( n  = 28) had used rubber dam on child patients ( P  < 0.05). Rubber dam was never used by 75% of respondents ( n  = 65) when placing posterior amalgam restorations, and by 21% of respondents ( n  = 18) when placing anterior composite restorations. Rubber dam was used by 98% of the respondents ( n  = 85) when performing root canal treatments. Sixty-two per cent of respondents ( n  = 54) believed their use of rubber dam would decrease once leaving the dental school.
Conclusion  Whilst dental students believe that rubber dam is relevant to clinical dentistry, there are negative perceptions associated with its use amongst dental students. More than half of those questioned predicted their use of rubber dam would decrease once in independent practice. Greater emphasis should be placed on the advantages of using rubber dam in clinical dentistry whilst at dental school.  相似文献   
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