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831.
A series of 430 men aged 40 to 79 years underwent transrectal ultrasonography (TRUS) as part of a community survey of benign prostatic hyperplasia (BPH). We describe a reproducible method of prostate volume estimation and discuss the implications of prostate dimension changes in BPH. The mean prostate and adenoma volumes for the group were 32 ml (SD 14) and 15 ml (SD 11) respectively. The antero-posterior dimension of the prostate (APD) had the strongest correlation with gland volume compared with the transverse dimension (TD) and length (L). The mean ratio of adenoma volume to prostate volume was 0.45 (SD 0.13) and this increased with increasing gland volume. There was a modest correlation between the ratio and prostate volume. BPH is characterised by a proportionally greater increase in the APD compared with L and TD and by an increasing adenoma/prostate ratio. TRUS is useful in assessing the type and extent of adenoma and prostate enlargement in BPH. 相似文献
832.
DD Men'shikov EB Lazareva TS Popova LU Shramko IS Tokaev GV Zalogueva IN Gaponova 《Canadian Metallurgical Quarterly》1997,42(12):10-15
The influence of food fibres and plant proteins on microorganisms, bacteriophages, antibiotics and penicillinase was studied in vitro. It was shown that pectin was the only agent that had a bactericidal effect on the most widely distributed pathogenic and opportunistic microorganisms and did not influence indigenic microflora. High concentrations of pectin (> 2 per cent) had an inactivating effect on therapeutic bacteriophages. There was also a decrease in the antimicrobial activity of penicillins. The other agents tested i.e. wheat bran, soya isolate and soybean flour had no influence on microorganisms, bacteriophages and antibiotics. No sorption activity of the food fibres and plant proteins with respect to microorganisms and antibiotics or their effect on penicillinase was observed. 相似文献
833.
SV Joag I Adany Z Li L Foresman DM Pinson C Wang EB Stephens R Raghavan O Narayan 《Canadian Metallurgical Quarterly》1997,71(5):4016-4023
Chimeric simian/human immunodeficiency virus (SHIV) consists of the env, vpu, tat, and rev genes of human immunodeficiency virus type 1 (HIV-1) on a background of simian immunodeficiency virus (SIV). We derived a SHIV that caused CD4+ cell loss and AIDS in pig-tailed macaques (S. V. Joag, Z. Li, L. Foresman, E. B. Stephens, L. J. Zhao, I. Adany, D. M. Pinson, H. M. McClure, and O. Narayan, J. Virol. 70:3189-3197, 1996) and used a cell-free stock of this virus (SHIV(KU-1)) to inoculate macaques by the intravaginal route. Macaques developed high virus burdens and severe loss of CD4+ cells within 1 month, even when inoculated with only a single animal infectious dose of the virus by the intravaginal route. The infection was characterized by a burst of virus replication that peaked during the first week following intravenous inoculation and a week later in the intravaginally inoculated animals. Intravaginally inoculated animals died within 6 months, with CD4+ counts of <30/microl in peripheral blood, anemia, weight loss, and opportunistic infections (malaria, toxoplasmosis, cryptosporidiosis, and Pneumocystis carinii pneumonia). To evaluate the kinetics of virus spread, we inoculated macaques intravaginally and euthanized them after 2, 4, 7, and 15 days postinoculation. In situ hybridization and immunocytochemistry revealed cells expressing viral RNA and protein in the vagina, uterus, and pelvic and mesenteric lymph nodes in the macaque euthanized on day 2. By day 4, virus-infected cells had disseminated to the spleen and thymus, and by day 15, global elimination of CD4+ T cells was in full progress. Kinetics of viral replication and CD4+ loss were similar in an animal inoculated with pathogenic SHIV orally. This provides a sexual-transmission model of human AIDS that can be used to study the pathogenesis of mucosal infection and to evaluate the efficacy of vaccines and drugs directed against HIV-1. 相似文献
834.
We report a 24-year-old woman, her 6-year-old son and her 17-month-old daughter, who all suffer from a rare congenital genodermatosis first delineated by Huriez et al. in the 1960s. The clinical features of this autosomal dominant condition include scleroatrophy of the hands and feet, nail hypoplasia, mild palmoplantar keratoderma and hypohidrosis. Histological changes are non-specific, but immunohistological and ultrastructural examination in our index patient revealed an almost complete absence of epidermal Langerhans cells in the affected skin. This new finding may be linked to the cancer proneness of the scleroatrophic skin. In this family, the grandmother had died at the age of 37 years from metastatic squamous cell carcinoma which had arisen on the thenar eminence. 相似文献
835.
836.
Although stuttering has long been acknowledged as a familial disorder, the nature of a genetic component remains unclear. Most previous data used in genetic studies were obtained primarily from adults who stutter and may be biased in several respects. The purpose of this investigation was to quantify the frequency of stuttering in relatives of preschool-age children who stutter, and who were first seen close to the onset of the disorder. Detailed pedigrees (family trees), including first-, second-, and third-degree relatives, were obtained from parents of 69 children who stuttered. We found, as have previous studies, that more male than female relatives ever stuttered, but that female subjects who stuttered had more female relatives who ever stuttered than did male subjects. In order to identify the genetic model most consistent with the observed patterns of stuttering transmission, we conducted segregation analyses. Results from these analyses suggest that transmission of a single major genetic locus increasing the liability to stuttering best accounts for the transmission of stuttering in families of preschool-age children who stutter. 相似文献
837.
EB Siegel 《Canadian Metallurgical Quarterly》1977,11(4):675-678
Polyene antifungal antibiotics produce various degrees of membrane damage in sheep erythrocytes in vitro. Mediocidin, filipin, amphotericin B, and candicidin were found to result in greater damage than nystatin, pimaricin, and amphotericin B methyl ester. The degree of sensitivity of the cells varied by 100-fold for mediocidin verus amphotericin B methyl ester as measured by curves of hemoglobin release versus drug concentration. In erythrocytes prelabeled with radioactive chromium, release of the isotope through polyene-damaged cell membranes was found to occur at lower drug concentrations than measurable hemoglobin release, and the percentage of isotope released at the highest drug dose was consistently greater than the percentage of hemoglobin released. Thus, the isotope assay is a more sensitive indicator of polyene-induced membrane damage in the test system. These significant differences in release of molecules through polyene-induced membrane lesions indicate the complex nature of the binding and further interactions of this class of drugs with the plasma membrane. 相似文献
838.
839.
840.
J Lette JL Tatum S Fraser DD Miller DD Waters G Heller EB Stanton HS Bom J Leppo S Nattel 《Canadian Metallurgical Quarterly》1995,2(1):3-17
Use of the acute hospital has markedly decreased over the past four decades for various reasons: the decentralization of diagnostic treatment technologies to out-of-hospital sites; the clinical substitutions of quick diagnostic testing of the ambulatory patient for the longer diagnostic testing of the hospitalized patient; the diminished use of hospital bed rest and the expanded use of exercise for treatment; the corporate organization of hospital work that emphasizes efficiency; and the group practice organization of generalists and specialists that avoids hospital use for the diagnosis of complex disorders in ambulatory patients. A smaller domain for hospital bed care and renewed attention to chronic disease and prevention in the community diminish the hold of the acute hospital on care. The evolution of more collaborative, decentralized arrangements promises to be a positive development for community care. 相似文献