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51.
An 11-year-old girl with osteosarcoma in the left distal femur, developed unilateral spontaneous pneumothorax. Pneumothorax was found at the initial presentation, but chest CT failed to reveal pulmonary metastases, bullae or blebs.
Résumé Une fillette de 11 ans présentant un ostéosarcome de la région distale du fémur, chez qui est apparu un pneumothorax spontané. Le pneumothorax a été constatéà la première visite, mais la tomographie par reconstruction d’image n’a permis de révéler ni métastases pulmonaires, ni bulles pulmonaires ou sous-pleurales.


Accepted: 7 October 1999  相似文献   
52.
Although magnetic resonance imaging (MRI) has improved the diagnostic accuracy of meniscal pathology, the authors believe that physical examination remains essential to the evaluation of knee pathology. In this study, the diagnostic accuracy of five clinical tests for meniscal pathology was prospectively evaluated in 160 patients, who thereafter underwent arthroscopy. 69% (109 knees) of the knees tested had associated ACL deficiency. There were 144 meniscal lesions in 130 of the 160 knees which were examined. The sensitivity of the tests was lower than the specificity. Conventional tests such as McMurray and Apley tests showed a low accuracy rate of 45% and 28% respectively. The diagnostic value of the axially loaded pivot shift test was significantly higher, indicating that this remains a useful diagnostic aid.  相似文献   
53.
PURPOSE: To determine the presence of fluorescein leakage from the iris and angle in normal subjects, and how it is affected by aging. METHODS: The subjects were 92 normal volunteers and patients with senile cataract who ranged in age from 20 to 93 years and were free from any systemic or ocular diseases. Fluorescein iris and angle photography and color iris and angle photography were performed using a goniolens and a photo slit lamp. RESULTS: Radial ciliary body vessels were found in 22 eyes (24%), radial iris vessels or trabecular vessels in 7 eyes (8%), and circular ciliary band vessels were seen in 4 eyes (4%). Goniovessels were found in 8 of 30 eyes (27%) of those under 50 years of age. No significant difference in the incidence of goniovessels was found between those over and under age 50 (P < .01). In the pupillary margin, fluorescein leakage was seen in 1 of 30 eyes (3%) in the age group under 50 years, whereas leakage was found in 30 of 62 eyes (48%) in the age group over 50 years. In the anterior chamber angle, leakage was seen in 4 of 30 eyes (13%) under age 50 years, and in 38 of 62 eyes (61%) over age 50 years (P < .05). CONCLUSIONS: These findings suggested that the incidence of leakage of fluorescein from the pupillary margin and anterior chamber angle tends to increase with age. Thus, when leakage of fluorescein in angle and iris is observed, it is important to consider the physiological changes resulting from aging.  相似文献   
54.
The distal photoreceptors in the tiered retina of Papilio exhibit different spectral sensitivities. There are at least two types of short-wavelength sensitive receptors: an ultraviolet receptor with a normal spectral shape and a violet receptor with a very narrow spectral bandwidth. Furthermore, a blue receptor, a double-peaked green receptor and a single-peaked green receptor exist. The violet receptor and single-peaked green receptor are only found in ommatidia that fluoresce under ultraviolet illumination. About 28% of the ommatidia in the ventral half of the retina exhibit the UV-induced fluorescence. The fluorescence originates from an ultraviolet-absorbing pigment, located in the most distal 70 microns of the ommatidium, that acts as an absorption filter, both for a UV visual pigment, causing the narrow spectral sensitivity of the violet receptor, and for a green visual pigment, causing a single-peaked green receptor.  相似文献   
55.
Stresgenin B was isolated as an inhibitor of heat-induced heat shock protein (HSP) gene expression from a culture broth of Streptomyces sp. AS-9 by silica gel chromatography and HPLC. The molecular formula of the novel compound was determined as C11H13NO5 by high resolution FAB-MS analysis, and the structure was determined by UV, 1H NMR, 13C NMR, HMQC, HMBC, and NOESY spectra. Stresgenin B inhibited heat-induced luciferase reporter-gene expression directed by the human hsp70B promoter in Chinese hamster ovary (CHO) cells at concentrations lower than the concentrations for inhibition of dexamethasone-induced luciferase reporter-gene expression directed by the mouse mammary tumor virus (MMTV)-LTR promoter. The inhibition of heat-induced reporter gene expression was evident even when cells were exposed to stresgenin B only during heat stress treatment. Moreover, the compound inhibited heat-induced syntheses of hsp72/73, hsp90, and hsp110 and thereby suppressed the induction of thermotolerance. Stresgenin B showed moderate cytotoxic activities against several neoplastic cell lines and also showed antibacterial activities against Micrococcus luteus, Bacillus subtilis and Staphylococcus aureus strains.  相似文献   
56.
Nocturnal eating/drinking syndrome secondary to neuroleptic-induced restless legs syndrome (RLS) occurred under treatment with low-dose haloperidol in a 51-year-old female schizophrenic patient. Polysomnographic investigation showed a low level of sleep efficacy, periodic leg movements, and a strict relationship between nocturnal eating episodes and non-rapid eye movement sleep. Her nocturnal eating and RLS were completely inhibited by clonazepam treatment. To our knowledge, this is the first published case of nocturnal eating/drinking syndrome secondary to neuroleptic-induced RLS.  相似文献   
57.
We report five patients with atypical parkinsonism characterized by freezing phenomenon, akinesia and axial rigidity without limb rigidity or tremor. These patients were selected from 252 patients with parkinsonism who were referred to our clinic from 1986 to 1993. They have common clinical features consisting of freezing phenomena involving all four extremities, especially in the initiation of walking, and marked axial rigidity; otherwise, neither supranuclear ophthalmoparesis nor nuchal dystonia was noted. Their clinical features did not change over several years except in one patient who later developed typical manifestations of progressive supranuclear palsy (PSP). Levodopa was of no effect on their symptoms. After excluding other possibilities, it is our conclusion that they represent an atypical form of PSP lying between the pure akinesia of Imai and Narabayashi and the typical form of PSP.  相似文献   
58.
Clinical study of growing up aneurysms: report of 25 cases   总被引:1,自引:0,他引:1  
Twenty-five cases of patients with growing up aneurysms are reported. Growth of the aneurysm was confirmed by repeated angiography within 1 month in 11 cases (short-term group), and for over 1 month in the other 14 cases (long-term group) following the initial angiography. Clinical history, shape and growth pattern of aneurysms, as well as hemodynamic factors that effect the growth were investigated in each group. The aneurysms were classified according to the shape into dome-type (smooth contour) and bleb-type (irregular contour). In all cases of the short-term group, the first angiography was performed because of rupture of the aneurysm. In this group, 4 cases bled again because of enlargement or the development of an aneurysmal bleb. Growth rate and the initial size of the aneurysm did not effect the potential of re-rupture. In the long-term group, 9 cases out of 14 (64.3%) had "non-ruptured aneurysm" at the time of first angiography. In the follow up, 5 cases were ruptured (two because of re-bleeding and three for the first time). In 3 out of these 5 cases, a bleb was demonstrated on initial angiography, and in another case, a bleb was demonstrated in follow-up angiography. Only one case ruptured because of the growth of the aneurysmal dome. Most of the aneurysms that rupture, in the follow-up survey, showed a larger growth rate in comparison with aneurysms that did not rupture. Many cases of this long-term group were associated with hypertension or vascular abnormalities which would effect the aneurysmal growth.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
59.
Itami C  Mizuno K  Kohno T  Nakamura S 《Brain research》2000,857(1-2):141-150
The maturation of cortical circuitry critically depends on experience. Recently, a model of silent synapse has been proposed as a mechanism of activity-mediated transition of immature synapse to mature synapse. It is not clear, however, how activity could regulate this transition. Here, we show the evidence that endogenous brain-derived neurotrophic factor (BDNF) is required for the maturation of glutamatergic synapse in developing mouse somatosensory cortex. Field potential recordings of thalamocortical glutamatergic synaptic activity with brain slices from the BDNF mutant mice showed that AMPA receptor responses are low, but NMDA receptor responses remain high in layer 4, thus, the relative contribution of AMPA receptor response is significantly lower compared to the age-matched wild-type mouse. Furthermore, optical images of development of thalamocortical connectivity with a voltage-sensitive dye showed that NMDA receptor-dominant synapse is established first in layer 4 and layer 5/6 then AMPA receptor response appears later in concomitant with reduction of NMDA receptor response in layer 4 and that the maturation of the silent synapse is impaired in the BDNF mutant mice. In layer 5/6, NMDA receptor response was suppressed without upregulation of AMPA receptor response. This process also required BDNF function. Interestingly, whisker-trimming of the wild-type mouse from just after birth showed quite similar results with the homozygous mutant of their whiskers left intact. Therefore, we would propose that BDNF is a critical mediator for the maturation of glutamatergic synapse in developing mouse somatosensory cortex.  相似文献   
60.
We report a patient with hemiparkinsonism associated with unilateral striatal necrosis of the contralateral side. The patient was an 18-year-old woman who had a two-month-history of difficulty in executing skilled movements with her right upper extremity. Neurological examination revealed that she had cogwheel rigidity and bradykinesia in her right upper and lower extremities. MRI revealed a well-delineated low signal intensity in T1-weighted and high signal intensity in T2-weighted images in the region of the putamen on the left side. Her laboratory data were unremarkable and mitochondrial gene mutation studies revealed no abnormality. It is extremely rare to encounter a case of parkinsonism associated with unilateral striatal necrosis.  相似文献   
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