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111.
Pyoderma gangrenosum (PG) is a rare, poorly understood skin disease that occurs in all age groups. Less than 0.4% of patients are infants and represent a diagnostic challenge as early lesions may resemble other skin disorders. Here we report for the first time three siblings affected with PG all presenting during infancy. Unlike the older age group, the ulcers spared the legs but involved the buttocks, thighs and perianal area in all the infants. Conclusion: This is the first reported family with PG affecting three siblings suggesting autosomal recessive inheritance. The diagnosis may be more difficult in infants due to absence of underlying associated disorders and the tendency of the lesions to appear in areas where infants frequently have other dermatoses. PG characteristically involves the buttocks, thighs and perianal area and spares the legs. 相似文献
112.
WH Lippy JM Burkey MJ Fucci AG Schuring FM Rizer 《Canadian Metallurgical Quarterly》1996,17(6):831-834
Clinical records were reviewed to examine the effectiveness of stapedectomy in patients 70 years and older. A total of 154 patients was studied, including 11 with profound hearing loss with long-standing otosclerosis. Ages at the time of surgery ranged from 70 to 92 years (mean, 76.3 years). The mean pure-tone average (500, 1,000, 2,000, and 4,000 Hz) improved 30.6 dB after surgery for the 143 patients in the main otosclerotic group and 26.8 dB for the patients in the profound-hearing-loss group. The rate of successful stapedectomies for the 70(+)-year-old patients (90.9%) and the younger comparison group (90.0%) were similar. These findings extend the documented range of stapedectomy as a safe and effective procedure through the eighth decade of life. 相似文献
113.
C Isidoro M Demoz D De Stefanis F Mainferme R Wattiaux FM Baccino 《Canadian Metallurgical Quarterly》1995,60(1):61-64
Using immunomagnetic cell separation and fluorescent in situ hybridization (FISH), we studied nine patients who had chronic granulocytic leukemia (CGL) for the proportion of interphase nuclei with Mbcr/abl fusion in a direct preparation of the bone marrow and also in the mononuclear cell (MNC), neutrophil, and B- and T-cell fractions of the peripheral blood. In five untreated patients, conventional cytogenetics revealed 97% to 100% Philadelphia chromosome (Ph)+ metaphases. In three of these five patients, FISH studies on bone marrow direct preparations and peripheral blood MNCs indicated that an Mbcr/abl fusion occurred in 62% to 69% of the cells. We observed 69% to 88% of nuclei with Mbcr/abl fusion within the neutrophil fractions. In contrast, the values were 12% to 39% within the T-cell fractions in the four patients we studied. B-cell fractions were studied in three patients, and only one had an abnormal value (58%). In the four patients receiving alpha-interferon therapy, the degree of conventional cytogenetic remission correlated best with the degree of FISH remission observed in the peripheral blood neutrophil fraction. Our results are in agreement with earlier studies in that both B and T lymphocytes may be involved with the clonal process in CGL. The FISH-based detection of Mbcr/abl fusion in the peripheral blood neutrophil compartment provided the best estimate for the proportion of Ph metaphases determined by conventional cytogenetics. 相似文献
114.
One of the main tasks of current cutaneous surgery is to completely eliminate the tumor while avoiding unnecessary normal tissue extirpation. This is especially important when removing facial tumors close to the external canthus, mouth angles and perialar regions. In all these areas we advise fusiform excision but with distal M-plasty in the nearest angle so as to avoid angle retraction. The same is true for mediofrontal tumors, as this often causes a drawing together of the eyebrows. We have reviewed all mediofrontal excisions carried out during the last six years. M-plasty following fusiform excision was always performed in the interglabellar area. The good results achieved allow us to recommend this technique in this location. 相似文献
115.
MG Beconi-Barker RD Roof L Millerioux FM Kausche TH Vidmar EB Smith JK Callahan VL Hubbard GA Smith TJ Gilbertson 《Canadian Metallurgical Quarterly》1995,673(2):231-244
2- and 4-Nitrophenyl beta-D-xylopyranosides (4 and 5) were transformed, via dibutyltin oxidemediated acylation, into the corresponding 2,3-di-O-benzoyl derivatives 11 and 15. Xylobiose and xylotriose were easily isolated by charcoal column chromatography from a commercially available material and converted into the di- and trisaccharide methyl 1-thio-beta-glycosides 36 and 37. The 2-and 4-nitrophenyl beta-glycosides of the beta-(1-->4)-D-xylo-oligosaccharides of dp 2-4 were synthesized by N-iodosuccinimide-silver triflate-promoted condensation using 11 and 15 as the glycosyl acceptors and ethyl 1-thio-beta-D-xylopyranoside triacetate 16, 36, and 37 as the glycosyl donors. Also described are an improved preparation of 4 and 5, and the synthesis of 1-naphthyl beta-D-xylopyranoside, as well as an alternative approach to the 2- and 4-nitrophenyl beta-xylobiosides. 相似文献
116.
Amyloplasts of starchy tissues such as those of maize (Zea mays L.) function in the synthesis and accumulation of starch during kernel development. ADP-glucose pyrophosphorylase (AGPase) is known to be located in chloroplasts, and for many years it was generally accepted that AGPase was also localized in amyloplasts of starchy tissues. Recent aqueous fractionation of young maize endosperm led to the conclusion that 95% of the cellular AGPase was extraplastidial, but immunolocalization studies at the electron- and light-microscopic levels supported the conclusion that maize endosperm AGPase was localized in the amyloplasts. We report the results of two nonaqueous procedures that provide evidence that in maize endosperms in the linear phase of starch accumulation, 90% or more of the cellular AGPase is extraplastidial. We also provide evidence that the brittle-1 protein (BT1), an adenylate translocator with a KTGGL motif common to the ADP-glucose-binding site of starch synthases and bacterial glycogen synthases, functions in the transfer of ADP-glucose into the amyloplast stroma. The importance of the BT1 translocator in starch accumulation in maize endosperms is demonstrated by the severely reduced starch content in bt1 mutant kernels. 相似文献
117.
The transient suppression of muscle contraction during the cutaneous silent period (CSP) could be produced either through postsynaptic inhibition of motoneurons or through presynaptic inhibition of the excitatory inputs to motoneurons that sustain voluntary contraction. We sought to delineate the mechanisms underlying the CSP in hand muscles by measuring changes in H-reflexes and motor-evoked potentials (MEPs) produced by transcranial magnetic stimulation (TMS) during the CSP in 10 healthy volunteers. H-reflexes and MEPs both measure the excitability of the motoneuron pool and activate similar subpopulations of motoneurons through different pathways. Inhibition of H-reflexes and MEPs of similar size was maximal at the midpoint of the CSP and gradually returned to baseline. The similar time course of recovery suggests that the H-reflex and MEP are affected by inhibition at a common site, most likely postsynaptic inhibition of the motoneurons. 相似文献
118.
J Ubogui FM Stengel MC Kien L Sevinsky L Rodríguez Lupo 《Canadian Metallurgical Quarterly》1998,134(11):1411-1412
We describe the use of weight-bearing foot tomograms. The outline of the food is drawn so as the axes of the metatarsal beyond the toes on the AP plain radiogram and the tomograms are done successively on each metatarsal. This morphological, but also functional, analysis enables exact diagnosis of excessive loading on the metatarsal head. This procedure is used in case of metatarsalgia with normal metatarsal length and in late post-traumatic sequellae of the forefoot. Surgical correction can then be precisely performed. 相似文献
119.
120.
A whole-body extract of Culicoides impunctatus induced a biphasic increase in oedema formation in ponies with insect hypersensitivity, with maxima after one and eight hours. The Culicoides antigen did not induce similar responses in ponies with no previous history of the disease. In insect-hypersensitive ponies the local administration of chlorpheniramine (12 micrograms) completely inhibited oedema formation in response to histamine (0.04 microgram) and to Culicoides antigen (0.5 microgram) at one hour, and the response to Culicoides antigen at eight hours was inhibited by 63 per cent. Chlorpheniramine also partially inhibited the accumulation of eosinophils and neutrophils induced by Culicoides antigen after two hours. 相似文献