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81.
A light microscopic and immunohistochemical evaluation of scars 总被引:3,自引:0,他引:3
BACKGROUND: Scars are commonly encountered by dermatopathologists and usually do not present a diagnostic challenge. However, in some cases, the pathologist may need to consider a broad differential diagnosis including fibrohistiocytic tumors, smooth muscle tumors, myofibroblastic proliferations and desmoplastic malignant melanoma. Although specific histologic aspects of scars have been well studied, a complete histochemical profile of scars, especially at various stages of evolution, has not been described. METHODS: Twenty-five cases of scars including 8 normal scars, 5 hypertrophic scars and 12 keloids were studied. Sections were examined with Verhoeff van Giesson, colloidal iron, Giemsa, smooth muscle actin (SMA), CD34, Factor XIIIa and S-100. RESULTS: All scars were negative for CD34 expression. Factor XIIIa immunostaining identified only rare dermal dendrocytes. S-100 was absent in 23 of 25 cases and stained scattered cells (less than 10%) in the other 2 cases. SMA was positive in 14 of 25 cases with 6 of these showing staining of up to 50% of spindled cells. Elastic fibers were markedly reduced or absent in all cases, mucin showed moderate or marked staining in three-fourths of the cases and dermal mast cells showed a moderate increase in 5 cases. CONCLUSIONS: These findings confirm prior reports that negative staining with CD34, Factor XIIIa and S-100 can help differentiate scars from dermatofibrosarcoma protuberans, dermatofibroma and desmoplastic malignant melanoma, respectively. SMA staining is much more variable and requires careful interpretation. 相似文献
82.
Mahesh Chandra Hegde M. Panduranga Kamath Kiran Bhojwani Ranjith Peter Polisetti Ravi Babu 《Indian journal of otolaryngology and head and neck surgery》2005,57(1):35-38
Objective A climical study was undertaken to analyze the age, sex distribution and symptomatology, sites of involvement and the prognosis
of the common types of benign lesions of larynx.
Study Design A five year retrospective study from 1997 to 2002.
Setting KMC Hospital Attavar —A tertiary referral hospital.
Patients A total of 42 patients with benign laryngeal lesions were included based on symptomatology such as hoarseness of voice, foreign
body sensation, throat pain, neck mass and cough and with positive clinical findings on indirect laryngoscopy and neck examination.
The patients ranged from 7–80 years. All non-operative cases and malignant cases were excluded. Diagnostic hematological and
radiological investigations and therapeutic microlyryngoscopic procedures were employed.
Results A male preponderance with M:F ratio of 3∶1 was observed. Majority of the patients were in the 30–40 age group. Vocal polyps
were the commonest type of lesion. In our study, hoarseness of voice, cough, foreign body sensation and throat pain proved
to be the commonest symptoms.
Conclusions Micro laryngeal surgery and voice rest offer a cost effective, useful and safe method for management of benign laryngeal lesions. 相似文献
83.
Mahesh Chandra Hedge Panduranga M. Kamath Suja Shreedharan Naveen Kumar Dannana Ravikumar M. Raju 《Indian journal of otolaryngology and head and neck surgery》2006,58(1):31-34
The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity was 97.29% and the specificity was 62.5%. 相似文献
84.
Expression of neural markers in human umbilical cord blood 总被引:48,自引:0,他引:48
85.
Kamath VJ Giuliano R Dauway EL Cantor A Berman C Ku NN Cox CE Reintgen DS 《Archives of surgery (Chicago, Ill. : 1960)》2001,136(6):688-692
BACKGROUND: Sentinel lymph node (SLN) biopsy techniques provide accurate nodal staging for breast cancer. In the past, complete lymph node dissection (CLND) (levels 1 and 2) was performed for breast cancer staging, although the therapeutic benefit of this more extensive procedure has remained controversial. HYPOTHESIS: It has been demonstrated that if the axillary SLN has no evidence of micrometastases, the nonsentinel lymph nodes (NSLNs) are unlikely to have metastases. OBJECTIVE: To determine which variables predict the probability of NSLN involvement in patients with primary breast carcinoma and SLN metastases. METHODS: An analysis of 101 women with SLN metastases and subsequent CLND was performed. Variables included size of the primary tumor, tumor volume in the SLN, staining techniques used to initially identify the micrometastases (cytokeratin immunohistochemical vs hematoxylin-eosin), number of SLNs harvested, and number of NSLNs involved with the metastases. Tumor size was determined by the invasive component of the primary tumor. Patients with ductal carcinoma in situ who were upstaged with cytokeratin staining were considered to have stage T1a tumors. RESULTS: Sentinel lymph node micrometastases (<2 mm) detected initially by cytokeratin staining were associated with a 7.6% (2/26) incidence of positive CLND compared with a 25% (5/20) incidence when micrometastases were detected initially by routine hematoxylin-eosin staining. Sentinel lymph node micrometastases, regardless of identification technique, inferred a risk of 15.2% (7/46) for NSLN involvement. As the volume of tumor in the SLN increased (ie, <2 mm, >2 mm, grossly visible tumor), so did the risk of NSLN metastases (P<.001). CONCLUSIONS: Our study demonstrated that patients with micrometastases detected initially by cytokeratin staining had low-volume disease in the SLN with a small chance of having metastases in higher-echelon nodes in the regional basin other than the SLN. Characteristics of the SLN can provide information to determine the need for a complete axillary CLND. Complete lymph node dissection may not be necessary in patients with micrometastases detected initially by cytokeratin staining since the disease is confined to the SLN 92.4% of the time. However, the therapeutic value of CLND in breast cancer remains to be determined by further investigation. 相似文献
86.
DiRusso S Holly C Kamath R Cuff S Sullivan T Scharf H Tully T Nealon P Savino JA 《The Journal of trauma》2001,51(2):294-9; discussion 299-300
OBJECTIVE: The purpose of this study was to assess the impact on patient outcome and hospital performance of preparing for and achieving American College of Surgeons (ACS) Level I trauma verification. METHODS: The center was a previously designated state regional trauma center located adjacent to a major metropolitan area. Preparation for ACS verification began in early 1996 and was completed in early 1998. Final verification took place in April 1999. Data were analyzed before (1994) and after (1998) the process. There was a marked increase in administrative support with trauma named one of the hospital's six centers of excellence. Two full-time board-certified trauma/critical care surgeons were added to the current six trauma surgeons. Their major focus was trauma care. Trauma support staff was also increased with case managers, a trauma nurse practitioner, additional trauma registrars, and administrative support staff. Education and continuous quality improvement were markedly expanded starting in 1996. RESULTS: There were 1,098 trauma patients admitted in 1994, and 1,658 in 1998. Overall mortality decreased (1994, 7.38%; 1998, 5.37%; p < 0.05). There was a marked decrease in mortality for severely injured (Injury Severity Score > 30) patients (1994, 44% mortality [38 of 86]; 1998, 27% [22 of 80]; p < 0.04). Average length of stay also decreased (1994, 12.22 days; 1998, 9.87 days; p < 0.02). This yielded an estimated cost savings for 1998 of greater than $4,000 per patient (total saving estimate of $7.4 million). CONCLUSION: Trauma system improvement as related to achieving ACS Level I verification appeared to have a positive impact on survival and patient care. There were cost savings realized that helped alleviate the added expense of this system improvement. The process of achieving ACS Level I verification is worthwhile and can be cost effective. 相似文献
87.
Trifluoperazine (TFP) is effective in modulating DNA damage/repair in doxorubicin (DOX) treated cells. In the present study we have characterised the resistance phenotype of parental sensitive L1210 mouse leukaemia cells (L1210/S) adapted to grow in the presence of 0.017 microns DOX+5 microM TFP (L1210/DT). Although with prolonged exposure, 0.017 microM DOX alone produced < 35% cell kill in L1210/S cells, similar cytotoxicity was achieved at 0.43 microM DOX in L1210/S cells selected in the presence of 0.017 microM DOX+5 microM TFP. L1210/DT cells were > 30-fold resistant to DOX following a 3 h drug exposure in a soft agar colony assay. In contrast, DOX sensitivity in cells adapted to grow in 5 microM TFP alone was comparable to L1210/S cells. Resistance to other inhibitors of topoisomerase II in L1210/DT cells was > 30-fold to etoposide and > 6-fold to amsacrine. The levels of the 170 kDa and 180 kDa isoforms of topoisomerase II in an immunoblot were comparable between the L1210/S and L1210/DT cells. Cross resistance to vincristine in the L1210/DT cells was accompanied by the overexpression of plasma membrane P-glycoprotein. Although a 1.5-2-fold decrease in accumulation of etoposide and DOX was observed in the L1210/DT cells, drug levels for equivalent DNA damage in the alkaline elution assay were > 5-fold higher in the L1210/DT versus L1210/S cells. No abrogation in the modulating effects of TFP on DOX, VP-16 or amsacrine induced cytotoxicity was apparent in the L1210/DT cells. Results suggest that: (a) TFP in combination with low concentrations DOX can induce the selection of cells with the multidrug resistant phenotype; and (b) characteristics of cells selected for resistance to DOX or DOX plus TFP are comparable. 相似文献
88.
89.
R R Hansebout R N Lamont M V Kamath 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1985,12(2):83-87
The internal spinal cord blood flow was measured in dogs at the site of local cooling using hydrogen polarography. Blood flow decreased to 50% of the normothermic values during cooling of the cord to a central temperature of 16 degrees Celsius. Upon cessation of cooling internal blood flow rapidly returned to normal values. Implications of this finding for the treatment of spinal cord injury are discussed. 相似文献
90.
S Kamath 《American journal of epidemiology》1975,102(2):191-195
One hundred and ninety hepatitis B surface antigen positive (HBsAG+) sera were subtyped, belonging to : blood donors, hepatitis patients, patients and staff in a hemodialysis unit, all from Kuala Lumpur; Malaysian aborigines from three jungle locations in Peninsular Malaysia; and East Malaysians from Sarawak, East Malaysia; Three subtypes adr, adw and ayw were present in Malaysia in the following frequencies: 44%, 29%, and 27%, respectively; In Kuala Lumpur 87% had subdeterminant d and 13 per cent y, whereas in the deep jungle aborigines of Perak and Pahang, the y subdeterminant was present in 87% and the d in 13%. A similar pattern of preponderance of y prevailed in Sarawak, East Malaysia. In Kuala Lumpur the two main ethnic groups, Malays and Chinese, differed in subtype distribution, in that adr predominated in the Malays (61%), while the adw predominated in the Chinese (51%); Subtype distribution was not related to age or sex of carriers of the antigen, or to whether they had hepatitis, or asymptomatic antigenemia. 相似文献