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排序方式: 共有2132条查询结果,搜索用时 10 毫秒
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A young male patient with schistosomiasis and sarcoma of the urinary bladder is presented. Total cystectomy followed by radiotherapy was performed. The gross appearance, microscopic findings of the tumor and an outline of the disease are discussed. 相似文献
3.
W M Pick J E Myers A R Sayed J Dhansay R L George A W Barday 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,78(1):7-10
A prevalence study of hypertension in 8 family practices in low socio-economic areas of Cape Town examined 1,046 patients over the age of 15 years. The crude prevalence rate of hypertension was 20.26%. There was no significant sex difference. Systolic pressure, diastolic pressure and hypertensive status increased with age and body mass index (BMI). There were complex relationships with regard to sex in that the female sex was predictive of hypertensive status after the age of 45 years unexplained by differences in BMI. After adjusting for age, BMI and sex differences, widowhood, poor education, obesity, a family history of hypertension or stroke and a past history of hypertension were significant predictors of hypertensive status. Smoking status, occupational social class or property ownership were not predictive. Fifty-one per cent of hypertensive subjects were treated. Of those receiving treatment, 30% were controlled resulting in a control prevalence of only 18%. Younger male subjects were better controlled by treatment. A strong need for improved diagnosis and treatment of hypertension in family practice exists in this region. 相似文献
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Our objectives were to study the types and incidence of thyroid follicular lesions coexisting with Hashimoto's thyroiditis (HT), the pitfalls in their cytodiagnosis, and the effect on management. All cases of HT diagnosed by fine-needle aspiration (FNA) and/or histology over a 7-yr period were retrospectively studied. HT coexisted with follicular adenoma (FA) in 6 cases, follicular variant of papillary carcinoma (FVPC) in 1 case, and goitrous nodule (GN) in 2 cases. The overall incidence rates of thyroid neoplasm and goitrous nodules coexistent with HT were 15% and 3.5%, respectively. A preoperative FNA diagnosis was available in 10 histologically proven cases of HT. A false-positive diagnosis of follicular neoplasm (FN) that led to unnecessary thyroidectomies was given in 3 cases. In 2 of these, the cytological diagnosis was HT with the possibility of coexisting FN, and in the third case, the cytological finding of HT was misinterpreted as FN. The main causes of these diagnostic pitfalls were the presence of hyperplastic follicular cells with nuclear pleomorphism, a paucity of lymphoid cells in burned-out HT, and lack of ones exposure. Nuclear pleomorphism was observed in none of the follicular adenomas. FNA diagnosed accurately the coexisting lesions in 6 cases; 3 FA, 1 FVPC, and 2 GN, but it did not sample HT. In one case, FNA diagnosed correctly both HT and the coexisting FA. Therefore, the presence of a coexistent neoplasm or goitrous nodule reduced the chances of sampling HT by 85.7%, with no false-negative results. Indeed, aspiration on and around the thyroid nodule helps in sampling HT. However, HT may dominate the smear and obscure neoplasia. This can be avoided if the procedure is performed by the pathologist and the aspiration is done on the nodule only. The overlapping cytological features of FN and HT were the main causes of false-positive results. This can be reduced by avoiding the diagnosis of FN in the presence of follicular-cell pleomorphism and/or moderate to excessive numbers of lymphoid cells, provided proper aspiration technique is maintained. 相似文献
6.
Occurrence of infection with a parvovirus-like agent in children with sickle cell anaemia during a two-year period. 总被引:4,自引:2,他引:4 下载免费PDF全文
M J Anderson L R Davis J Hodgson S E Jones L Murtaza J R Pattison C E Stroud J M White 《Journal of clinical pathology》1982,35(7):744-749
The occurrence of infection with a parvovirus-like agent during the period April 1979-May 1981 in children attending a single sickle cell clinic in London was investigated. Virus was detected in serum by counter-current immunoelectrophoresis (CIE) and immunoelectron microscopy (IEM). Viral antibody was detected by CIE and specific IgM antibody by an IgM-antibody capture assay. Of the 68 children studied nine presented in aplastic crisis and evidence of infection with the parvovirus-like agent at the time of the crisis was found in all nine. Eighteen of the other children were antibody-positive at some time during the study. In 11 children there was no evidence of recent infection; however, two of these had a history of aplastic crisis in previous years. The other seven seroconverted during the course of the study but did not show any haematological effects. Five of these had a primary infection, one appeared to have reinfection and in the seventh there were insufficient data to distinguish between the two. Possible explanations for the difference between those presenting with aplastic crisis and those with asymptomatic seroconversion are discussed. 相似文献
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Jamal M. Arif Mohammed Kunhi Yunus M. Siddiqui Khalid A. El Sayed Khaled Y. Orabi Amal Al-Hazzani Mohammed N. Al-Ahdal Fahad M. Al-Khodairy 《Medicinal chemistry research》2004,13(6-7):553-562
In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with
the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed
for BP-derived DNA adducts by 32P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50
μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual
DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary
results, these compounds may be classified as potential genotoxic. 相似文献
9.
Nehal Elkhoshkhany Samir Marzouk Mohammed El-Sherbiny Heba Ibrahim Bozena Burtan-Gwizdala Mohammed S. Alqahtani Khalid I. Hussien Manuela Reben El Sayed Yousef 《Materials》2022,15(15)
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection. 相似文献
10.
Abdel Bar FM Zaghloul AM Bachawal SV Sylvester PW Ahmad KF El Sayed KA 《Journal of natural products》2008,71(10):1787-1790
Three new 28-norlupane triterpenes, 28-norlup-20(29)-en-3beta-hydroxy-17beta-hydroperoxide (1), 28-norlup-20(29)-en-3beta-hydroxy-17alpha-hydroperoxide (2), and 20 S-17beta,29-epoxy-28-norlupan-3beta-ol (3), were isolated from the leaves of Melaleuca ericifolia along with eight known pentacyclic triterpenes. The structures of the new compounds were elucidated by spectroscopic methods including 1D and 2D NMR spectroscopy and mass spectrometry. The isolated triterpenes were evaluated for antiproliferative activity against the malignant +SA mammary epithelial cell line. 相似文献