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21.
Wijeyesinghe E. C. R.; Hawkins T.; keavey Pauline M.; Wilkinson R. 《Nephrology, dialysis, transplantation》1988,3(2):209-213
The value of the Technetium-99m tin colloid (TTC) scan in thediagnosis of renal transplant rejection occurring more than1 month following transplantation was assessed. To our knowledge,use of this agent has not previously been reported. Gamma cameraimaging was performed on 15 occasions in 14 patients in whomplasma creatinine was rising and in three patients in whom renalfunction was stable. Both a qualitative and a quantitative assessmentof images was made. The radioactivity recorded over the graft at 1216 mmpost injection was expressed as a percentage of that recordedat 04 min. In the nine patients in whom graft perfusionwas adequate to allow interpretation of the TTC scan and inwhom rejection was diagnosed by biopsy (six cases) or on clinicalgrounds (three cases), the index ranged from 45 to 153%. Intwo patients the graft was poorly perfused and the accumulationof TTC was predictably low despite the presence of rejection.In the seven patients with either a stable creatinine or withrising creatinine not due to rejection, the index ranged from5 to 43%. Previously reported studies have shown that sulphur colloidsmay be of value in diagnosing graft rejection. This study suggeststhat Tc99m tin colloid may be regarded as a suitable alternativescanning agent and that some simplification of data collectionand analysis can be achieved. 相似文献
22.
Summary
In the last decades back pain has reached dramatic proportions in industrialized countries. Disorders of the back are nowadays
the leading cause of direct and indirect health care costs. Accurate prevalence estimates are needed to serve as a basis for
health care evaluations. A review of epidemiologic studies in the general population reveals that back pain has reached a
prevalence of 40 % for current pain. 7 to 18 % are “frequently”, “often”, “daily” or “constantly” affected. 75 % of the adult
population suffers from back pain during the last year. 80 to 90 % of the adult population in industrialized countries experience
back pain ever. Gender specific differences are only present in severe, chronic forms which are more often experienced by
women. Back pain has a prevalence maximum at 50 to 64 years. Older persons display lower prevalence estimates. The prevalence
maximum in men is one decade earlier than in women. There are several potential explanations for this prevalence pattern that
are discussed in the article. Back pain can be classified by location, temporal characteristics, pain intensity and pain history.
Currently, for none of these dimensions generally accepted, uniformly employed and validated definitions are available. In
most of the industrialized countries back pain is one of the most expensive symptoms. 75–90 % of the direct and indirect health
care costs were caused by those 5–10 % of patients who are disabled. As predictors of back pain a history of back pain and
job satisfaction play by far a more important role than the extensively studied mechanical factors. For a first episode of
back pain the prognosis is favorable. If the pain persist for more than three months the prognosis is unfavorable. After six
months of absenteeism because of back pain more than half of the afflicted never return to work. Rarely back pain is present
as a single symptom. In more than 80 % back pain is associated with pain in at least one joint. It remains to be studied if
back pain may be viewed as an entity or as part of a more complex pain syndrome.
相似文献
23.
M. Sibille N. Deigat V. Olagnier D. Vital Durand R. Levrat 《European journal of clinical pharmacology》1992,42(4):389-393
Summary All the clinical, laboratory and electrocardiographic adverse events detected during 24 Phase I studies in the same unit over a 5 y period are reported here. 430 healthy male volunteers were involved, corresponding to 5488 days of follow-up.The overall incidence of adverse events was 13.5%, with a significant difference between active drug (15.3%) and placebo (7.4%) treatments. There were 69 distinct types of adverse events. Headache was the most frequent symptom (2%). There were severe adverse events in 20 cases (0.36%), with an incidence of 20/430 per subject (4.6%). There were no deaths or life-threatening events.Although the main objective of Phase I studies is to determine the maximum dose tolerated, cause-effect relationships with adverse events are hard to establish, because of the frequency of adverse events with placebo, and because of the limited number of subjects included such studies. 相似文献
24.
Markus Friedrich Wolfram Sterry Khusru Asadullah 《Journal der Deutschen Dermatologischen Gesellschaft》2003,1(1):12-21
The current standard systemic therapeutic modalities for psoriasis have many potential side effects. Progress made in the understanding of the pathophysiology of psoriasis as a T‐cell‐mediated dermatosis provide options for new more precise therapeutic approaches. These immunological therapeutic strategies involve the inhibition/depletion of activated T‐lymphocytes, the inhibition of antigen presentation and thus the regulation of T‐cell activation, the inhibition of adhesion of inflammatory cells, the inhibition of effects of proinflammatory mediators and the administration of antiinflammatory cytokines. This article summarizes these new systemic therapeutic approaches. Clinical results in the early studies have been mixed. In the next years further results of phase II‐ and phase III‐studies may be expected, which should allow better assessment of the potential of those particular approaches. Some of these approaches could lead to the approval of new drugs to treat psoriasis and to enhance or replace already existing therapeutic options. Furthermore results of therapeutic experiments should contribute to a better understanding of the disease. As we learn which mechanisms are more or less important for the disease, we will be better able to plan intervention strategies. 相似文献
25.
M. -H. Smet F. de Zegher M. Vanderschueren-Lodeweyckx G. Marchal 《European radiology》1992,2(1):57-61
In this study, magnetic resonance imaging (MRI) was performed to document potentially present morphostructural abnormalities of the hypothalamopituitary region in seven infants (age 0–21 months) who presented very early in life with clinical and biochemical evidence of hypopituitarism. Four infants had associated congenital cerebro-facial malformations.The following anatomical abnormalities were identified in variable combinations: ectopic neurohypophysis absence of the pituitary stalk, extreme elongation of the pituitary stalk, aplasia of the anterior pituitary lobe and no identification of the hypothalamopituitary complex.MRI proved to be very sensitive in the identification of structural malformations of the hypothalamopituitary region in infants with or without cerebro-facial malformations. AllhwuLll the magnetic resonance image does not appear to be a good predictor of endocrine dysfunction, it provides us more insight into the precise aetiology of this disorder and may be therefore of diagnostic, prognostic and therapeutic importance. 相似文献
26.
Kay Teschke Susan M. Kennedy Andrew F. Olshan 《American journal of industrial medicine》1994,26(3):327-337
During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity. 相似文献
27.
P. M. Parizel G. Rodesch D. Balériaux D. Zegers de Beyl J. D'Haens J. Noterman C. Segebarth 《Neuroradiology》1989,31(1):75-79
Summary The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins. 相似文献
28.
29.
Porcine models have been used extensively for skin flap research because of the established similarity between the cutaneous
blood supply of the swine and humans. The Yucatan minipig provides an excellent model for researching the properties of random
cutaneous flaps, offering several advantages over other breeds of swine. In this study, a total of 67 random cutaneous dorsal
flank flaps measuring 4 × 14 cm were raised on nine Yucatan minipigs. The mean survival length (10.03 ± 1.60 cm) of the nondelayed
flaps was greater than others reported in the literature. The well-defined plane between the subcutaneous tissue and the panniculus
carnosus facilitated flap elevation consistently above the level of the panniculus carnosus thereby ensuring the creation
of a true random cutaneous flap. Furthermore, the hairless nature of the skin, particularly beneficial in studying chemical
peels, permits easy visualization and monitoring of any external skin changes. These advantages make the Yucatan minipig a
more desirable alternative to other breeds of swine for use in skin flap research. 相似文献
30.
Marc G Weisskopf Honglei Chen Michael A Schwarzschild Ichiro Kawachi Alberto Ascherio 《Movement disorders》2003,18(6):646-651
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question. 相似文献