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排序方式: 共有1742条查询结果,搜索用时 15 毫秒
71.
B. KAPPEL J. NIELSEN K. BROGAARD HANSEN M. MIKKELSEN AA. J. THERKELSEN 《BJOG : an international journal of obstetrics and gynaecology》1987,94(1):50-54
Summary. The clinical significance of placental perforation and bloodstained amniotic fluid was studied in a group of 7238 Danish women undergoing mid-trimester amniocentesis for prenatal diagnosis under ultrasound guidance. The risk of spontaneous abortion was significantly increased both in pregnancies where the placenta was perforated and in those with blood-stained amniotic fluid. The risk estimate nearly doubled after placental perforation and more than doubled with a bloody tap. It is concluded that for women at relatively low risk of a fetal genetic abnormality, the indication of the amniocentesis should be reconsidered if a placental perforation is unavoidable. 相似文献
72.
73.
Reijnierse M Dijkmans BA Hansen B Pope TL Kroon HM Holscher HC Breedveld FC Bloem JL 《European radiology》2001,11(3):467-473
The aim of this study was to evaluate if subjective symptoms, radiographic and especially MR parameters of cervical spine
involvement, can predict neurologic dysfunction in patients with severe rheumatoid arthritis (RA). Sequential radiographs,
MR imaging, and neurologic examination were performed yearly in 46 consecutive RA patients with symptoms indicative of cervical
spine involvement. Radiographic parameters were erosions of the dens or intervertebral joints, disc-space narrowing, horizontal
and vertical atlantoaxial subluxation, subluxations below C2, and the diameter of the spinal canal. The MR features evaluated
were presence of dens and atlas erosion, brainstem compression, subarachnoid space encroachment, pannus around the dens, abnormal
fat body caudal to the clivus, cervicomedullary angle, and distance of the dens to the line of McRae. Muscle weakness was
associated with a tenfold increased risk of neurologic dysfunction. Radiographic parameters were not associated. On MR images
atlas erosion and a decreased distance of the dens to the line of McRae showed a fivefold increased risk of neurologic dysfunction.
Subarachnoid space encroachment was associated with a 12-fold increased risk. Rheumatoid arthritis patients with muscle weakness
and subarachnoid space encroachment of the entire cervical spine have a highly increased risk of developing neurologic dysfunction.
Received: 31 December 1999 Revised: 30 May 2000 Accepted: 5 June 2000 相似文献
74.
Tamminga RY Noordhoek M Kroon J Faber-Nijholt R 《Pediatric hematology and oncology》2000,17(5):383-388
Ketamine is a drug widely used for analgesia and sedation of children for diagnostic and therapeutic procedures. The authors investigated in a randomized controlled clinical trial if diazepam premedication would have a beneficial effect on side effects related to ketamine anesthesia for bone marrow punctures (BMPs) in children with acute lymphoblastic leukemia (ALL). Sixteen children 4 years or older at the time of BMP were eligible. The first 2 BMPs after complete remission was obtained were studied. BMPs were performed under ketamine anesthesia (1.0-1.5 mg/kg iv), as usual. Patients were randomized to receive 1 h before the first BMP blinded, either diazepam or placebo orally and before the second BMP the other way round. Blood pressure, heart rate, and oxygen saturation were monitored, and patients were observed for signs of anxiety, pain, and other side effects. The patients were interviewed after each BMP and asked for their preference 1 week after the second BMP. Ketamine anesthesia appeared as safe and effective after diazepam premedication as after placebo premedication. From the interviews and questionnaires, it was clear that half of the children preferred diazepam premedication because of less awful dreaming and more gradual falling asleep and waking up. Diazepam premedication may be useful for selected children with ALL receiving ketamine anesthesia for BMPs. 相似文献
75.
Moderate and severe malnutrition are endemic in much of the developing world and in association with pockets of deprivation in the developed world. The cost in terms of individual and social development is high. The principles of effective management are clearly documented. A low cost, community based treatment programme for moderately and severely malnourished children under 3 years of age was established at a health centre in rural Jamaica. Children were followed up monthly and defaulters were rigorously recalled. Management consisted of carefully delivered dietary advice, antibiotics, anthelminthics, and vitamin supplements. All children improved and the response of 36 children, who were treated in the first year, showed an accelerated weight gain, with catch-up growth and the maintenance of length gain. There was a significant increase in the weight for age, at 1.9% per month over six months, which exceeds the rate reported with food supplementation programmes and nutrition rehabilitation centres. 相似文献
76.
77.
Pathophysiologic considerations as well as non-comparative clinical results suggest that very high purity concentrates may slow immunologic deterioration in human immunodeficiency virus (HIV)-infected hemophiliacs. In an attempt to evaluate this hypothesis, we prospectively compared CD4 cell counts, skin testing responses, and changes of the clinical status in 20 asymptomatic HIV-positive hemophiliacs, randomly assigned to continue the treatment with an intermediate purity concentrate or to receive a very high purity product, purified by immunoaffinity chromatography with monoclonal antibodies. In the group switched to the very high purity concentrate there was no significant change of the CD4 cell counts over the 96-week follow-up period, whereas in the group continued on the intermediate purity concentrate, a highly significant decline was detected (P less than .013). Furthermore, in the very high purity group, four of six anergic patients at entry acquired reactivity to skin testing. The results of this study clearly support the use of very high purity concentrates for the replacement therapy of HIV-infected hemophiliacs. 相似文献
78.
Masclee AA; Hopman WP; Corstens FH; Rosenbusch G; Jansen JB; Lamers CB 《Radiology》1989,173(2):407-410
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying. 相似文献
79.
We describe an automated method for calcium assay, for use with the Cobas-Bio centrifugal analyzer. Calcium is reacted with cresolphthalein complexone and the absorbance of the calcium--dye complex at 575 nm is measured. EDTA is then added to break up the calcium--dye complex and the absorbance at 575 nm is re-measured, to correct for endogenous color and turbidity. Day-to-day precision data, determined over four months, were as follows: mean = 92.9 mg/L, CV = 1.47%; n = 216; mean = 128.7 mg/L, CV = 1.72%; n = 216. Comparison of the Cobas-Bio method (y) with an atomic absorption spectrometric method (x) gave the following results: y = 1.012x--2.05, r = 0.991, Sy/x = 1.2, mean x = 92.63 mg/L, mean y = 91.69 mg/L, n = 74. Hemoglobin, bilirubin, or turbidity does not interfere. At the medical decision value (110 mg/L), the overall analytical error is 4.6 mg/L, which is less than the 5 mg/L allowable (95% confidence limit) error. 相似文献
80.