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61.
Prevalence of six types of human papillomavirus in inverted papilloma and papillary transitional cell carcinoma of the bladder: an evaluation by polymerase chain reaction. 总被引:2,自引:0,他引:2 下载免费PDF全文
AIMS: To study the prevalence of high risk oncogenic human papillomaviruses (HPV) in inverted papilloma and papillary transitional cell carcinoma of the bladder. METHODS: Ten cases of inverted papilloma and 20 cases of papillary transitional cell carcinoma of the bladder from Chinese patients in Hong Kong were examined for the presence of HPV type 6, 11, 16, 18, 31, and 33 genomes using the polymerase chain reaction and HPV type specific primer probe combinations on paraffin wax embedded biopsy specimens. RESULTS: Of the 10 cases of inverted papilloma, cases 1 and 6 showed the presence of HPV types 16 and 18, respectively. Six of the 20 papillary transitional cell carcinomas were positive for HPV type 18. The other HPV types were not detected. CONCLUSIONS: HPV type 18 was found in 60% and 30% of cases of inverted papilloma and papillary transitional cell carcinoma of the bladder, respectively. These tumours were rarely associated with HPV types 6, 11, 16, 31, and 33. The role of HPV type 18 in oncogenesis of inverted papilloma and transitional cell carcinoma of the bladder requires further studies. 相似文献
62.
The human parvovirus B19 is now known to be one of the causative agents of nonimmune hydrops fetalis and spontaneous abortions in pregnant women. The presence of the viral proteins and antibodies in fetuses of B19-infected women suggests that the virus can cross the placental barrier. In order to gain an insight into the mechanism of intrauterine fetal infection and the virus-induced hydrops fetalis, we examined whether human umbilical cord blood cells were permissive for B19 replication. Cord blood cells were infected with B19 in vitro, and Southern blot analyses of low M(r) DNA isolated from these cells revealed the presence of the characteristic replicative intermediates of B19 DNA. In addition, B19 genome expression in cord blood cells was detected by Northern blot analysis. Quantitative DNA dot blot analysis of culture supernatants documented complete assembly and release of B19 progeny virions in these cells. The progeny virions were biologically active in secondary infections of normal human bone marrow cells. The human umbilical cord blood cells may be a useful alternative to bone marrow and fetal liver culture systems for further studies on B19 since the need for bone marrow donors is obviated and, unlike fetal tissues, there are no ethical questions associated with the experimental use of cord blood because it is normally discarded. These studies also suggest that the umbilical cord blood may be a site for active replication of parvovirus B19 in vivo and may thus provide a means for transmission of the virus during intrauterine fetal infections. 相似文献
63.
Quernin MH Poonkuzhali B Médard Y Dennison D Srivastava A Krishnamoorthy R Chandy M Jacqz-Aigrain E 《Journal of chromatography. B, Biomedical sciences and applications》1999,721(1):147-152
A high-performance liquid chromatographic (HPLC) method was developed and validated for the determination of busulfan in plasma. Busulfan was extracted in toluene, derivatized by 2,3,5,6-tetrafluorothiophenol to obtain di-TFTP-butane, the derivatization product was then re-extracted in toluene and injected into the HPLC system with ultraviolet detection (wavelength: 275 nm). Recovery from extraction was 80%, the limit of quantification was 50 ng/ml and linearity ranged from 50 to 2000 ng/ml. In addition, forty-two samples obtained from pediatric patients treated with busulfan were analyzed by the HPLC and GC-MS assays based on the same derivatization procedure. The correlation between the di-TFTP-butane concentrations was highly significant (p<0.0001), demonstrating that the two methods were in good agreement. 相似文献
64.
R. C. Yadav Chanchal Rajput S. P. Srivastava H. K. Kukreja 《Indian journal of otolaryngology and head and neck surgery》1985,37(4):163-164
A case of Primary Carcinoma of the Frontal Sinus. 相似文献
65.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
66.
67.
Pulmonary tuberculosis among contacts of patients with tuberculosis in an urban Indian population. 总被引:1,自引:0,他引:1
R A Kumar M Saran B L Verma R N Srivastava 《Journal of epidemiology and community health》1984,38(3):253-258
The study was conducted among 1810 contacts of 50 index "cases"/"suspects" of pulmonary tuberculosis including 312 household and 1498 neighbourhood contacts in the Jhansi city of Uttar Pradesh. The overall prevalence of radiologically active and bacteriologically confirmed tuberculosis was 2.9% and 1.1%. The prevalence rates of radiologically active and bacteriologically confirmed disease, although comparatively high in both the contact groups, were significantly higher in household (5.4% and 2.6%) than in neighbourhood contacts (2.3% and 0.8%). Significant differences in distribution of secondary cases among clusters were observed. Although higher prevalence rates were found in contacts of sputum positive source than in contacts of sputum negative source in both the contact groups, the statistical difference was observed to be insignificant. Case yield among contact symptomatics was 80.0% (30.8% cases and 49.2% suspects). 相似文献
68.
Reilly Catherine Chuchvara Nadiya Cucalon Jennifer Srivastava Radhika Rao Babar K. 《Lasers in medical science》2021,36(5):1077-1084
Lasers in Medical Science - The evaluation of pigmented lesions on tattooed skin poses a diagnostic challenge for dermatologists, as a nevus may be partially or completely obscured by tattoo... 相似文献
69.
I. Foo A. J. R. Macfarlane D. Srivastava A. Bhaskar H. Barker R. Knaggs N. Eipe A. F. Smith 《Anaesthesia》2021,76(2):238-250
Intravenous lidocaine is used widely for its effect on postoperative pain and recovery but it can be, and has been, fatal when used inappropriately and incorrectly. The risk-benefit ratio of i.v. lidocaine varies with type of surgery and with patient factors such as comorbidity (including pre-existing chronic pain). This consensus statement aims to address three questions. First, does i.v. lidocaine effectively reduce postoperative pain and facilitate recovery? Second, is i.v. lidocaine safe? Third, does the fact that i.v. lidocaine is not licensed for this indication affect its use? We suggest that i.v. lidocaine should be regarded as a ‘high-risk’ medicine. Individual anaesthetists may feel that, in selected patients, i.v. lidocaine may be beneficial as part of a multimodal peri-operative pain management strategy. This approach should be approved by hospital medication governance systems, and the individual clinical decision should be made with properly informed consent from the patient concerned. If i.v. lidocaine is used, we recommend an initial dose of no more than 1.5 mg.kg-1, calculated using the patient’s ideal body weight and given as an infusion over 10 min. Thereafter, an infusion of no more than 1.5 mg.kg-1.h-1 for no longer than 24 h is recommended, subject to review and re-assessment. Intravenous lidocaine should not be used at the same time as, or within the period of action of, other local anaesthetic interventions. This includes not starting i.v. lidocaine within 4 h after any nerve block, and not performing any nerve block until 4 h after discontinuing an i.v. lidocaine infusion. 相似文献
70.
Daniel M. Green Mingjuan Wang Matthew Krasin DeoKumar Srivastava Songul Onder Dennis W. Jay Kirsten K. Ness William Greene Jennifer Q. Lanctot Kyla C. Shelton Liang Zhu Daniel A. Mulrooney Matthew J. Ehrhardt Andrew M. Davidoff Leslie L. Robison Melissa M. Hudson 《Journal of the American Society of Nephrology : JASN》2021,32(4):983
BackgroundSurvivors of childhood cancer may be at increased risk for treatment-related kidney dysfunction. Although associations with acute kidney toxicity are well described, evidence informing late kidney sequelae is less robust.MethodsTo define the prevalence of and risk factors for impaired kidney function among adult survivors of childhood cancer who had been diagnosed ≥10 years earlier, we evaluated kidney function (eGFR and proteinuria). We abstracted information from medical records about exposure to chemotherapeutic agents, surgery, and radiation treatment and evaluated the latter as the percentage of the total kidney volume treated with ≥5 Gy (V5), ≥10 Gy (V10), ≥15 Gy (V15), and ≥20 Gy (V20). We also used multivariable logistic regression models to assess demographic and clinical factors associated with impaired kidney function and Elastic Net to perform model selection for outcomes of kidney function.ResultsOf the 2753 survivors, 51.3% were men, and 82.5% were non-Hispanic White. Median age at diagnosis was 7.3 years (interquartile range [IQR], 3.3–13.2), and mean age was 31.4 years (IQR, 25.8–37.8) at evaluation. Time from diagnosis was 23.2 years (IQR, 17.6–29.7). Approximately 2.1% had stages 3–5 CKD. Older age at evaluation; grade ≥2 hypertension; increasing cumulative dose of ifosfamide, cisplatin, or carboplatin; treatment ever with a calcineurin inhibitor; and volume of kidney irradiated to ≥5 or ≥10 Gy increased the odds for stages 3–5 CKD. Nephrectomy was significantly associated with stages 3–5 CKD in models for V15 or V20.ConclusionsWe found that 2.1% of our cohort of childhood cancer survivors had stages 3–5 CKD. These data may inform screening guidelines and new protocol development. 相似文献