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71.
Tamponade treatment in epistaxis is painful and the patient needs hospitalisation. Irrigation with hot water was introduced as a treatment of epistaxis 100 years ago. This study compares the two treatments with respect to effect, recurrence, pain, and length of hospital stay. Forty-four consecutive patients with posterior epistaxis were randomized to receive treatment with either hot water (HWI) or tamponade. In the group of patients treated with HWI, the treatment had to be stopped in seven patients (33%) because of lack of cooperation; nine patients (43%) could be discharged from hospital with no need for further treatment, whereas five patients (24%) had recurrent epistaxis requiring additional tamponade treatment. Among patients treated with tamponade, 14 patients (61%) could be discharged from hospital with no need for further treatment, while nine patients (39%) had recurrent epistaxis requiring additional tamponade treatment. Compared with the tamponade treatment, HWI is almost as effective, the hospital stay is shorter, and the treatment is significantly less painful. 相似文献
72.
Regenerative and degenerative changes of cartilage were studied in animals by micromorphological methods and autoradiography. Cartilage lesions of defined size were set in the femoral condyle of rabbits of variing age by means of an electrical drill developed by us. We used juvenile animals, 3 months old, and senile animals 4 years old. The lesions were studied by lightmicroscopy, electronmicroscopy and scanning electron microscopy. In young animals we were able to demonstrate prevailing reparative changes after injury and the potency for genuine regeneration originating from cartilage. Isolated chondral lesions develop reactive tissue originating mainly from superficial parts of the cartilage. When subchondral bone is exposed we see granulation tissue filling up the defect and change by metaplasia. The replacing tissue originating from superficial cartilage as well as from subchondral bone is able to fill the defect within 3 months. In the replacing tissue originating from cartilage we find fibroblasts and fibrocytes with many mitoses. Consecutively the cells are rounding increasingly. Finally chondrocytes are developing. At the same time as these reparative changes occur we see degenerative changes with decreased mucopolysaccharide synthesis, cell necroses with consecutive decrease in number of cells and singular small cluster. In old animals we could not demonstrate any reparative or regenerative changes after injuries; the artificial defect in cartilage persists. Instead, degenerative changes with signs of arthrosis are developing rapidly: chondroitin sulfate synthesis is decreased, there is ample cluster formation, cell necrosis, decrease in number of cells, and incorporation of paraplasmatic substances in cartilage. We could not demonstrate any mitoses. The causes for the inability of cartilage of aged individuals for reparative changes are discussed. 相似文献
73.
Non-atypical adenomatous hyperplasia was found in 13.5% of 111 biopsies obtained from long-term, predominantly black, users of Oracon. An association between length of time of use (95 cycles for those with adenomatous hyperplasia versus 73 for those without) and the development of adenomatous hyperplasia was noted, but there was no association with hypertension or obesity. Cystic glandular dilatation was seen in 63% but was not thought to represent hyperplasia. No more advanced lesions were seen. 相似文献
74.
E Myhre 《Canadian Metallurgical Quarterly》1976,96(26):1352-1356
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HO Curth 《Canadian Metallurgical Quarterly》1976,95(4):433-436
A man born with a unilateral epidermal naevus on the right side of the abdomen developed at puberty symmetrical benign acanthosis nigricans in the body folds. The symmetrical eruption later disappeared completely. The unilateral epidermal naevus and the symmetrical eruption showed identical histological features, i.e. those of acanthosis nigricans. At the age of 32 he developed a muco-epidermoid cancer of the left parotid gland. A decision whether the association of unilateral epidermal naevi with malignant tumours occurs with unusual frequency requires (a) a long follow-up of the patient with the unilateral naevus, (b) a differentiation of the unilateral eruption from unilateral malignant acanthosis nigricans and (c) statistical evidence. 相似文献
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tRNA pseudouridylation activities have been detected in embryonic mouse cell fractions and in extracts from HeLa, mouse L-cell and baby hamster kidney (BHK) cell lines. These activities were identified by the use of heterologous reaction systems, with tRNA from hisT strains of Salmonella typhimurium as substrate. hisT mutants are defective for an enzyme that forms psi residues in the anticodon region of many tRNAs and accumulate undermodified species of tRNA. The pseudouridylation activity from BHK cells has been examined in detail and quantitated by a modified tritium release assay (Cortese, R., Kammen, H.O., Spengler, S.J., and Ames, B.N. (1974) J. Biol. Chem. 249, 1103-1108). Maximal rates of tritium release required a suitable cationic environment (optimally, a combination of Mg2+ and NH4+) and a thiol reductant. The activity was totally inhibited in the presence of thiol-reactive reagents, such as 5,5'-dithiobis(2-nitrobenzoic acid) and p-chloromercuribenzoate. A major portion of this 3H release activity was associated with psi modification reactions. This conclusion stems from the following observations: (a) BHK extracts preferentially catalyzed a release of 3H from hisT [5-3H]tRNA, rather than from similarly labeled wild type tRNA; (b) this activity was specific for protons attached to C5 of the pyrimidine rings; no release of 3H was obtained with hisT or wild type [6-3H]tRNA as substrate; (c) the reaction products of hisT tRNA with BHK enzyme were examined by reverse phase column chromatography of tRNAPhe isoacceptors on RPC-5 columns. The enzyme modified both of the principal isoacceptors of hisT tRNAPhe to an equal extent, yielding products indistinguishable from wild type tRNAPhe. Significant levels of 3H release were obtained by the action of enzyme on wild type [5-3H]tRNA, even after gel filtration of the enzyme. This suggests that the enzyme may be able to hypermodify certain species of wild type S. typhimurium tRNA. The activities for wild type tRNA and hisT tRNA appeared to be associated with the same enzyme. 相似文献