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71.
Findings in 31 pediatric patients with pain and dysfunction of the temporomandibular joint (TMJ) are reported. The average age was 14 years (range, 8-16) and the average duration of symptoms was 21.4 months (range, 3 mo.-5 yr.). Internal derangements were found in 29 patients (94%) and degenerative arthritis in 13 (42%). In 12 patients (39%), the problem could be traced to an injury to the jaw. Secondary condylar hypoplasia was associated with the meniscal abnormality in 3 patients (10%). Further awareness of internal derangements of the TMJ in the pediatric population should permit greater recognition of their etiology. It is important that treatment be initiated as soon as possible, not only to minimize the development of osseous disease in young adults but also to prevent facial growth deformities.  相似文献   
72.
Ureterovesical obstruction and megaloureter: diagnosis by real-time US   总被引:1,自引:0,他引:1  
Wood  BP; Ben-Ami  T; Teele  RL; Rabinowitz  R 《Radiology》1985,156(1):79-81
Forty infants and children were accurately diagnosed with real-time ultrasound (US) as having megaloureter secondary to ureterovesical junction (UVJ) obstruction by an adynamic, distal ureteral segment. Characteristic US findings were dilatation of the distal ureter, often disproportionate to the appearance of the upper collecting system; lower ureteral hyperperistalsis; and a sharply tapered, incurving, distal adynamic segment, 1-3 cm long. Real-time US, used routinely in preliminary evaluation of the urinary tract in children, can facilitate early diagnosis of UVJ obstruction and thus prevent significant loss of renal function.  相似文献   
73.
知母中呋甾皂甙的研究   总被引:16,自引:2,他引:14  
自知母 Anemarrhena asphodeloides Bge.根茎的乙醇提取物中,经硅胶柱层析和制备型HPLC分得四种呋甾皂甙。用化学反应和波谱(IR,FAB-MS,EI-MS,1HNMR,13CNMR,DEPT,一维多重接力CoSY,二维接力HOHAHA,1H-1H COSY,1H-13C COSY和NOE差谱)解析,确定其结构为知母皂贰B(anemarsaponinB,I),(25S)-26-O-β-D-吡喃葡萄糖基-5β-呋甾-20(22)-烯-3β,26-二醇-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃哺葡萄糖甙(Ⅱ),(25S)-26-O-β-D-吡喃葡萄糖基-22-羟基-5β-呋甾-3β,26-二醉-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃半乳糖甙(Ⅲ),(25S)-26-O-β-D-吡喃葡萄糖基-22-甲氧基-5β-呋甾-3β,26-二醇-3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃半乳糖甙(Ⅳ)。Ⅱ为一新的呋甾皂甙,命名为知母皂甙C;化合物Ⅳ为首次从知母中分离得到,命名为知母皂甙E。初步的药理实验显示,化合物1~Ⅳ均有一定的清除羟自由基的作用。  相似文献   
74.
De Smet  AA; Robinson  RG; Johnson  BE; Lukert  BP 《Radiology》1988,166(2):497-500
A prospective study of thoracic and lumbar spinal fracture distribution and its relationship to thoracic kyphosis was performed in 87 women with osteoporosis. Anterior wedge fractures were most commonly seen in the midthoracic spine and about the thoracolumbar junction, whereas central compression fractures were most common from the first to the fourth lumbar levels. Solitary wedge fractures did not occur above the seventh thoracic vertebra, suggesting that a cause other than osteoporosis must be suspected in any patient with an isolated high thoracic fracture. Analysis of the spinal radiographs obtained in an additional 16 women without osteoporosis revealed that both forms of fracture were unusual in this small group with normal spinal mineralization. The number of anterior wedge fractures in the thoracic spine correlated (r = .546) with the degree of thoracic kyphosis. However, 19% of the women with no thoracic fractures still had thoracic hyperkyphosis. The authors conclude that the hyperkyphosis of osteoporotic women is related to anterior compression fractures but also has contributing nonskeletal factors.  相似文献   
75.
Rosen  GM; Griffeth  LK; Brown  MA; Drayer  BP 《Radiology》1987,163(1):239-243
The diagnosis of various disorders of the cerebrospinal fluid (CSF) with magnetic resonance (MR) imaging may require the intrathecal administration of a paramagnetic contrast agent. Furthermore, the CSF route provides direct access to the brain, circumventing the blood-brain barrier. Three nitroxides, two charged and one uncharged, were administered intrathecally to dogs to assess their potential as contrast agents for MR imaging of the CSF. Nitroxide concentrations and proton T1 values were measured in samples of CSF removed at various times after nitroxide administration, and pharmacokinetic curves were constructed. The charged nitroxides had considerably longer half-lives than the uncharged compound. On in vivo MR imaging of the CSF (surrounding the upper cervical cord and brain stem) in one dog, use of a charged nitroxide as contrast agent led to considerably higher CSF signal intensity than was observed in the nonenhanced, baseline T1-weighted images. This effect was achieved at low doses (20 mumol) and sustained for at least 90 minutes. The intrathecal use of nitroxides as contrast agents for MR imaging warrants continued investigation.  相似文献   
76.
77.
78.
Cytokine dysregulation in the post-Q-fever fatigue syndrome   总被引:1,自引:4,他引:1  
The post-Q-fever fatigue syndrome (QFS) (inappropriate fatigue, myalgia and arthralgia, night sweats, changes in mood and sleep patterns) follows about 20% of laboratory-proven, acute primary Q-fever cases. Cytokine dysregulation resulting from chronic immune stimulation and modulation by persistence of Coxiella burnetii cells or their antigens is hypothesized. We studied cytokine release patterns of peripheral blood mononuclear cells (PBMC) stimulated with various ligands in short- term culture, from 18 patients with active QFS, and 27 controls: six with resolving QFS, five who had had acute primary Q-fever without subsequent QFS, eight healthy Q-fever vaccinees and eight healthy subjects without Q-fever antibody. Conditioned media (CM) from PBMC stimulated in short-term culture with Q-fever antigens, PHA or measles antigen (as an unrelated antigen) were assayed for IL-2, IL-4, IL-5, IL- 6, IL-10 and IFN gamma by AgEIA, and for IL-1 and TNF alpha/beta by bioassay. Aberrant cytokine release patterns were observed with PBMC from QFS patients when stimulated with Q-fever antigens: an accentuated release of IL-6 which was significantly [p = 0.01, non-parametric one- way analysis of variance (ANOVA)] in excess of medians for all four control groups. With IL-2, the number of responders in the active QFS group was decreased relative to control groups (Fisher's exact test, p = 0.01) whereas the number of IFN gamma responders was increased (Fisher's exact test, p = 0.0008). Significant correlations were observed between concentrations of IL-6 in CM, total symptom scores, and scores for other key symptoms.   相似文献   
79.
BACKGROUND: Self-medication with antibiotics may increase the risk of inappropriate use and the selection of resistant bacteria. One of the triggers for using self-medication may be past experience with antibiotics prescribed by health professionals. We examined the association between prescribed use and self-medication with antibiotics. METHODS: A population survey was conducted in 19 European countries, covering 15,548 respondents. Multinomial logistic regression analysis was used to study the relationship between prescribed use and self-medication for all symptoms/diseases and for upper respiratory tract infections (URTIs). RESULTS: The association between prescribed use and self-medication was modified by source of self-medication, region in Europe and education. This association was consistently stronger for self-medication from leftovers than from other sources, primarily directly from a pharmacy. It was stronger also for respondents from Northern/Western Europe than respondents from Eastern Europe and Southern Europe and those with low education. Prescribed use for URTIs (minor ailments such as throat symptom, influenza, etc.) increased the likelihood of self-medication with leftover antibiotics for these symptoms/diseases in all European regions. CONCLUSIONS: Our study shows consistent associations between prescribed use and self-medication with antibiotics from leftovers, but has not been able to support the hypothesis that self-medication from other sources than leftovers is triggered by earlier prescribed use. Preventing leftovers may be one effective way of preventing self-medication. This can be achieved by ensuring that the amount dispensed corresponds to the amount prescribed, by educating patients and by making doctors aware that prescribing for minor ailments may increase the risk of self-medication for such ailments.  相似文献   
80.
Post-infection fatigue syndrome following Q fever   总被引:3,自引:2,他引:3  
In 1989, 147 individuals in the West Midlands, UK, were infected with Q fever. Five years later, following anecdotal reports of fatigue, we used a questionnaire-based case-control study to determine the prevalence of chronic fatigue syndrome symptoms in this group. Replies from 71 patients were compared with those from 142 age- and sex-matched controls. Increased sweating (52.9% vs. 31.6%, p = 0.006), breathlessness (50.7% vs. 30.6%, p = 0.006), blurred vision (34.3% vs. 17.8%, p = 0.016) and undue tiredness (68.7% vs. 51.5%, p = 0.03) were found in controls compared to cases. These findings were similar to those in Australian abbatoir workers occupationally exposed to Q fever. CDC criteria for chronic fatigue syndrome were fulfilled by 42.3% of cases and 26% of controls. Using visual analogue scores, symptoms were more severe in cases than in controls. Our findings support the existence of a chronic fatigue state following acute Q fever, in a group of patients exposed just once to the organism, and in circumstances free of such confounding factors as lawsuits over compensation.   相似文献   
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