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11.
Krishna SM James S Kattoor J Balaram P 《Indian journal of pathology & microbiology》2004,47(2):181-185
Nasopharyngeal carcinoma (NPC) is a rare malignancy world-wide. It shows an increasing trend in the southern parts of India. Genetic alterations brought about by environmental factors, HPV and EBV are thought to be crucial for NPC carcinogenesis. This study reports for the first time the incidence of HPV infection in NPC in Southern India. Detection of HPV was carried out in 36 NPC and 10 adenoid lesions by immunohistochemical analysis. 38.8% of NPC were positive for HPV with higher positivity in WHO Type I and WHO Type II cancers. One among 10 adenoid lesions also showed presence of HPV. The patients belonged to low socio-economic status and had exposure to either tobacco or alcohol alone or in combination or kitchen smoke. 相似文献
12.
Polyclonal anti-PSA is more sensitive but less specific than monoclonal anti-PSA: Implications for diagnostic prostatic pathology 总被引:3,自引:0,他引:3
Varma M Morgan M Jasani B Tamboli P Amin MB 《American journal of clinical pathology》2002,118(2):202-207
Prostate-specific antigen (PSA) production by nonprostatic tissues has been reported, casting doubts on its specificity. The immunohistochemical relative specificity and sensitivity of PSA expression using monoclonal and polyclonal anti-PSA was analyzed on 60 prostate carcinomas, 40 normal seminal vesicles, and 310 nonprostatic tumors. All nonprostatic tumors proved negative with both antibodies. However, 13 (32%) seminal vesicles showed immunoreactivity with polyclonal anti-PSA, but none showed immunoreactivity with the monoclonal antibody. The sensitivity of the 2 antibodies for prostate cancer varied with tumor grade. In Gleason pattern 3, both antibodies showed diffuse immunostaining in all cases. In Gleason pattern 5, polyclonal anti-PSA showed diffuse (>95%) tumor cell positivity in 18 cases (90%), while with the monoclonal antibody, 7 cases (35%) showed only focal (<10%) tumor cell immunoreactivity. Thus, monoclonal anti-PSA seems to be useful in small gland proliferations in which the differential diagnosis includes seminal vesicle, while for poorly differentiated neoplasms, polyclonal anti-PSA is considered superior. Sections of high-grade prostate cancer should be included as positive controls for PSA immunostaining. 相似文献
13.
M. John Hicks Victor A. Saldivar Murali M. Chintagumpala Marc E. Horowitz Linda D. Cooley James P. Barrish Edith P. Hawkins Claire Langston 《Ultrastructural pathology》1995,19(5):395-400
Malignant melanoma of soft parts (MMSP) was originally described as a distinct entity by Enzinger in 1965 and was termed “clear cell sarcoma of tendons and aponeuroses” because of its association with tenosynovial structures. It has been shown immunophenotypically and ultrastructurally that this tumor is derived from neuroectoderm and shares a number of features with cutaneous melanoma. Over 95% of MMSPs present in the extremities, with the head and neck region (1.9%) being an unusual site. This study presents an additional case of MMSP of the head and neck region involving the posterior cervical region in a 15-year-old Hispanic male and reviews the literature on MMSP. Ultrastructural examination showed rudimentary cell attachments, smooth cell membranes, discontinuous basal lamina, scanty glycogen, and occasional premelanosomes in some tumor cells. Cytogenetic analysis showed a reciprocal translocation between the long arms of chromosomes 12 and 22 [t(12:22)(q13;q12.2)], characteristic for MMSP and not seen in cutaneous melanoma. Survival in MMSP has been correlated with tumor size, tumor necrosis, and ploidy status. Overall reported clinical outcome for this tumor is as follows: died of disease, 45%; alive with disease, 23%; no evidence of disease, 30%; and died of other causes, 2%. MMSP represents a distinct entity with a characteristic ultrastructural appearance and a tumor defining cytogenetic translocation. 相似文献
14.
Na+-K+-2Cl- cotransporter in immature cortical neurons: A role in intracellular Cl- regulation 总被引:7,自引:0,他引:7
Na+-K+-2Cl- cotransporter has been suggested to contribute to active intracellular Cl- accumulation in neurons at both early developmental and adult stages. In this report, we extensively characterized the Na+-K+-2Cl- cotransporter in primary culture of cortical neurons that were dissected from cerebral cortex of rat fetus at embryonic day 17. The Na+-K+-2Cl- cotransporter was expressed abundantly in soma and dendritic processes of cortical neurons evaluated by immunocytochemical staining. Western blot analysis revealed that an approximately 145-kDa cotransporter protein was present in cerebral cortex at the early postnatal (P0-P9) and adult stages. There was a time-dependent upregulation of the cotransporter activity in cortical neurons during the early postnatal development. A substantial level of bumetanide-sensitive K+ influx was detected in neurons cultured for 4-8 days in vitro (DIV 4-8). The cotransporter activity was increased significantly at DIV 12 and maintained at a steady level throughout DIV 12-14. Bumetanide-sensitive K+ influx was abolished completely in the absence of either extracellular Na+ or Cl-. Opening of gamma-aminobutyric acid (GABA)-activated Cl- channel or depletion of intracellular Cl- significantly stimulated the cotransporter activity. Moreover, the cotransporter activity was elevated significantly by activation of N-methyl-D-aspartate ionotropic glutamate receptor via a Ca2+-dependent mechanism. These results imply that the inwardly directed Na+-K+-2Cl- cotransporter is important in active accumulation of intracellular Cl- and may be responsible for GABA-mediated excitatory effect in immature cortical neurons. 相似文献
15.
Duggirala MK Cuddihy MT 《The New England journal of medicine》2003,348(14):1402-5; author reply 1402-5
16.
17.
N Murali E S Saravanan V J Ramesh B N Gangadhar N Jananakiramiah S S Kumar R Christopher D K Subbakrishna 《Anesthesia and analgesia》1999,89(5):1301-1304
The electroconvulsive therapy (ECT) guideline of the Royal College of Psychiatrists recommends a 0.5 mg/kg of succinylcholine for ECT modification. Our clinical experience suggests that this dose is insufficient for Indian patients. The dose recommended by the Royal College of Psychiatrists (0.5 mg/kg) and a larger dose (1 mg/kg) were compared in 50 patients referred for ECT. In one ECT session, patients were equally randomized to receive one of the two doses and in the next session they were switched to the other dose. The extent of motor seizure modification was rated on a five-point scale by two independent raters who were blinded to the succinylcholine dose. The interrater reliability was good (K = 0.85). "Poor" seizure modification occurred in 48% and 12% of patients with the 0.5 and 1 mg/kg doses, respectively. Of the 24 patients who had poor modification with 0.5 mg/kg, 20 had "good" modification in the session with 1 mg/kg (P < 0.001). A small delay (mean = 55 s) occurred in time to recover from the respiratory paralysis with the 1 mg/kg dose of succinylcholine. No patient, however, had prolonged apnea requiring special measures. We recommend 1 mg/kg of succinylcholine dose be used in the first ECT session. For subsequent sessions, the dose may be altered, depending on the response for optimal motor seizure modification. IMPLICATIONS: The dose of muscle relaxant (succinylcholine) recommended in modified electroconvulsive therapy is not based on empirical research. In the same patients (n = 50), two doses-0.5 mg/kg and 1 mg/kg-were compared during different electroconvulsive therapy sessions. The larger dose was more effective in modifying the peripheral convulsion. 相似文献
18.
Nagarathnam D Miao SW Lagu B Chiu G Fang J Murali Dhar TG Zhang J Tyagarajan S Marzabadi MR Zhang F Wong WC Sun W Tian D Wetzel JM Forray C Chang RS Broten TP Ransom RW Schorn TW Chen TB O'Malley S Kling P Schneck K Bendesky R Harrell CM 《Journal of medicinal chemistry》1999,42(23):4764-4777
Dihydropyrimidinones such as compound 12 exhibited high binding affinity and subtype selectivity for the cloned human alpha(1a) receptor. Systematic modifications of 12 led to identification of highly potent and subtype-selective compounds such as (+)-30 and (+)-103, with high binding affinity (K(i) = 0.2 nM) for alpha(1a) receptor and greater than 1500-fold selectivity over alpha(1b) and alpha(1d) adrenoceptors. The compounds were found to be functional antagonists in human, rat, and dog prostate tissues. Compound (+)-103 exhibited excellent selectively to inhibit intraurethral pressure (IUP) as compared to lowering diastolic blood pressure (DBP) in mongrel dogs (K(b)(DBP)/K(b)(IUP) = 40) suggesting uroselectivity for alpha(1a)-selective compounds. 相似文献
19.
Evaluation of social marketing of oral rehydration therapy. 总被引:1,自引:0,他引:1
Attempts, at social marketing of oral rehydration therapy (ORT) through television, in changing the knowledge and practice of mothers with regard to its use was assessed. One hundred and eighty seven consecutive mothers (38 excluded due to non use of ORT) were administered a preplanned questionnaire to assess their socio-economic profile, educational status, concept of diarrhea and correct use of ORT. Fifty nine mothers who watched these programmes on TV regularly formed the study group. These were compared with 90 mothers who had gained such knowledge from non-television sources. The correct application of knowledge of ORT was significantly better in study group compared with control group. The educational status of mothers had a positive impact on motivation to use ORT at home in the study group. Mass media campaigns through "TV spots" is an effective way of improving knowledge of mothers on ORT in a developing country. 相似文献
20.
Mohan Kameshwaran Kiran Natarajan Anand Kumar George Thomas Sathiya Murali 《Indian journal of otolaryngology and head and neck surgery》2003,55(3):196-199
Giant glomus tumors pose a challenge to the Otologist by virtue of their location and vascularity. A vast majority of them
present with tinnitus, conductive hearing loss and cranial nerve palsies. We report the case of a 16-year-old male patient
who presented with sudden right-sided sensorineural hearing loss. This is an unusual presentation of a giant glomus tumor.
We present the clinical features and management of this unusual case. 相似文献