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41.
A case of complete synostosis of the cervical spine in a 12-year-old girl is described. Differential diagnosis included dysontogenetic forms of synostosis, Klippel-Feil syndrome, rheumatic synostosis and synostosis of other inflammatory origin. This severe case, the first of its type to be described, appeared to be due to tuberculosis of the cervical spine. 相似文献
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The POEMS syndrome is a multisystem disorder characterised by polyneuropathy, organomegaly endocrinopathy, plasma cell dyscrasia and skin changes. Along with many further manifestations this rare syndrome may also include macroangiopathy and acute vascular obliteration. In the literature such vascular problems have received only little attention and most case reports refer to involvement of the coronary and lower limb arteries. To our knowledge, the association with recurrent strokes has not been described. We report on a 59-year-old male with a complete form of POEMS syndrome associated with multicentric Castleman's disease. Despite absence of vascular risk factors, myocardial infarctions and ischemic necroses of toes occurred, and recurrent ischemic strokes appeared during oral anticoagulation. Recurrent strokes may therefore represent a further complication of the POEMS syndrome. 相似文献
44.
It has long been assumed that the red cell membrane is highly permeable to gases because the molecules of gases are small, uncharged, and soluble in lipids, such as those of a bilayer. The disappearance of 12C18O16O from a red cell suspension as the 18O exchanges between labeled CO2 + HCO3- and unlabeled HOH provides a measure of the carbonic anhydrase (CA) activity (acceleration, or A) inside the cell and of the membrane self-exchange permeability to HCO3- (Pm,HCO-3). To test this technique, we added sufficient 4, 4'-diisothiocyanato-stilbene-2,2'-disulfonate (DIDS) to inhibit all the HCO3-/Cl- transport protein (Band III or capnophorin) in a red cell suspension. We found that DIDS reduced Pm,HCO-3 as expected, but also appeared to reduce intracellular A, although separate experiments showed it has no effect on CA activity in homogenous solution. A decrease in Pm,CO2 would explain this finding. With a more advanced computational model, which solves for CA activity and membrane permeabilities to both CO2 and HCO3-, we found that DIDS inhibited both Pm,HCO-3 and Pm,CO2, whereas intracellular CA activity remained unchanged. The mechanism by which DIDS reduces CO2 permeability may not be through an action on the lipid bilayer itself, but rather on a membrane transport protein, implying that this is a normal route for at least part of red cell CO2 exchange. 相似文献
45.
J. S. Forster G. C. Ball W. G. Davies J. S. GeigerJ. U. Andersen J. ChevallierJ. A. DaviesH. Geissel 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1994,90(1-4)
Dielectronic recombination for He-like 79Br has been measured for channeling along a 110 axis in Ni. The KLL resonance has a FWHM of 14% of the beam energy and an area corresponding to a density of about 6 electrons per atom. 相似文献
46.
Antibodies to Candida after operations on the heart 总被引:1,自引:0,他引:1
In order to determine the frequency of hypoxaemia and to evaluate the role of increased closing capacity in producing hypoxaemia in patients with cirrhosis of the liver, 13 patients with well-established cirrhosis were studied. Arterial blood gases, spirometry, lung volume, and closing capacity measurements were made with the patients in the seated and recumbent positions after exclusion of cardiopulmonary dysfunction. Four of 13 and six of 12 patients exhibited significant hypoxaemia in the seated and recumbent positions respectively. Five of 13 patients showed a closing capacity greater than predicted. This frequency of increased closing capacity was not higher than in a group of smokers of the same age. Unlike Ruff et al. (1971), we did not find a consistent relationship between hypoxaemia and closing capacity. 相似文献
47.
Estrogen supplementation in postmenopausal women offers significant cardiovascular protection. The mechanism for this benefit is unclear but may be due to an interaction of estrogen with the blood vessel wall (vascular smooth muscle and endothelium). We examined the response of weight-matched female and male endothelium-intact and -denuded aortae to 17 beta-estradiol, its interaction with noradrenaline, and the effect of N-nitro-L-arginine. Estradiol produced relaxation responses that were significantly greater in female endothelium-intact preparations. This response was sensitive to N-nitro-L-arginine, while the response to 17 beta-estradiol in male endothelum-intact and both female and male endothelum-denuded preparations was resistant. Estradiol also inhibited contractions to noradrenaline, which was more pronounced in the female endothelium-intact aortic rings. These data imply that estradiol interacts preferentially with the female vascular endothelium, but there exists an endothelium-independent process that can also be activated in the male aorta. Further studies are warranted to elucidate these differential mechanisms. 相似文献
48.
Severe hemophiliacs with intractable bleeding into one or more joints despite adequate clotting factor replacement therapy are difficult management problems. Synovectomy has controlled bleeding only in joints without significant arthritis destruction. Total joint replacements have been performed in arthropathic joints, but not when uncontrolled bleeding was a concurrent problem. This report describes a hemophiliac with uncontrolled bleeding into an arthritic knee who was successfully managed by combining synvectomy with total knee replacement. 相似文献
49.
PS Weisner GR Bower LA Dollimore AM Forster B Higley AE Storey 《Canadian Metallurgical Quarterly》1993,20(8):661-666
Technetium-99m exametazime (99mTc-d,l-HMPAO), prepared by the reconstitution of the Ceretec kit, is widely used in the investigation of regional cerebral blood flow. The radiochemical purity specification of not less than 80% lipophilic complex requires that the kit is used within 30 min of reconstitution. In certain circumstances this imposes restrictions on its clinical availability. A number of approaches to extending the 30-min shelf life have been proposed and these are discussed. A method of stabilising the kit by the addition of 200 micrograms cobalt chloride hexahydrate (CoCl2 x 6H2O) in 2 ml of water is described. The addition of this solution can extend the shelf life of the reconstituted kit to at least 5 h post reconstitution. 相似文献
50.