Displaying publications 21 - 40 of 123 in total

Abstract:
Sort:
  1. Ng KH, Siar CH
    J Nihon Univ Sch Dent, 1997 Dec;39(4):171-5.
    PMID: 9476429
    This report reviews the clinicopathologic characteristics of 104 cases of odontomas diagnosed in the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, over a 29-year period (1967-1995). The results showed no real predilection in terms of sex (M:F ratio, 1:1), race (45.2% Malays, 40.4% Chinese, 10.6% Indians and 3.8% other races) or site (maxilla:mandible ratio, 1: 1.04) distribution. The mean age at presentation was 24.8 years and the age range was 3-74 years. There were 102 intraosseous and 2 extraosseous odontomas. Swelling was the most common presenting complaint. The majority of cases (81.9%) were clinically diagnosed as odontomas. The treatment of choice was surgical enucleation. Compound (43.3%) and complex (35.5%) odontomas were the two most common histological types encountered. The present findings correlate favorably with reported studies from other geographic areas.
  2. Ng KH, Siar CH
    J Laryngol Otol, 1996 Aug;110(8):757-62.
    PMID: 8869610
    We reviewed the clinicopathological characteristics of 13 cases of calcifying epithelial odontogenic tumour (CEOT) (Pindborg tumour) diagnosed in the Division on Stomatology, Institute for Medical Research, Kuala Lumpur, over a 29-year period. There were eight female and five male patients. These consisted of eight (61.5 per cent) Malays, three (23.1 per cent) Chinese, one (7.7 per cent) Indian and one (7.7 per cent) Melanau. Their ages at presentation ranged from 19-61 years (mean age, 31.8 years). There were 12 central and one peripheral CEOT. Of these, 76.9 per cent of cases were located in the maxilla, the remaining in the mandible. The commonest clinical diagnosis was a dentigerous cyst (66.7 per cent). Enucleation was the main mode of treatment. Histologically, sheets and strands of polyhedral epithelial cells containing eosinophilic, homogeneous globules with Liesegang rings were observed. One case also showed extensive calcification and clear cell differentiation. Immunohistochemistry revealed a variable keratin staining of the CEOT epithelium, confirming its heterogeneity.
  3. Siar CH, Ng KH
    J Nihon Univ Sch Dent, 1992 Jun;34(2):96-105.
    PMID: 1380072
    Twelve pleomorphic adenomas of minor salivary gland origin were examined for the distribution of S-100 protein, detected using the peroxidase-antiperoxidase (PAP) method. Strong S-100 protein immunoreactivity was noted in areas containing plasmacytoid cells, stellate and spindle cells against a myxochondroid or hyalinous stroma, and solid epithelial areas. Tubular and duct-like structures showed variable stainability. Stromal tissue and normal salivary glands were generally negative for S-100 protein. These findings were compared with those reported elsewhere.
  4. Siar CH, Ng KH
    Br J Oral Maxillofac Surg, 1988 Jun;26(3):215-20.
    PMID: 2456095
    The records of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, Malaysia, were reviewed for the incidence of odontogenic keratocysts of the orthokeratinised variety, during the 20-year-period, 1967 to 1986. Nine cases were found. The clinical, histological and radiological features of these cases are reported. Many features were similar to previous reports of this entity but a peak incidence in the second decade of life, an almost even distribution in the maxilla and mandible, and a distinct predilection for the Chinese were observed. It is suggested that these features may be peculiar to Malaysians.
  5. Siar CH, Ng KH
    Br J Oral Maxillofac Surg, 1991 Apr;29(2):106-9.
    PMID: 2049349
    The combined epithelial odontogenic tumour represents a hybrid lesion comprising primarily areas of adenomatoid odontogenic tumour intermixed with foci of calcifying epithelial odontogenic tumour. Five such cases retrieved from the files of the Division of Stomatology, Institute for Medical Research, Kuala Lumpur, and four others from the existing literature were analysed. A mean age of 18.8 years, a female preponderance (66.7%) with a male to female ratio of 1:2 and predilection for the mandible (55.6%) were observed. All cases were treated by conservative surgery and the lack of recurrence confirmed the innocuous nature of this lesion.
  6. Ng KH, Siar CH
    Oral Surg. Oral Med. Oral Pathol., 1990 Aug;70(2):210-3.
    PMID: 2290651
    This report details a case of mandibular peripheral ameloblastoma having a clear cell component. The latter consisted of ovoid cells with vacuolated or clear cytoplasm and vesicular or pyknotic nuclei that may be disposed as discrete clusters or show direct transition from typical acanthomatous areas. Comparison of this lesion with other odontogenic and nonodontogenic tumors that contain clear cells is discussed in the context of the differential diagnosis.
  7. Ng KH, Siar CH
    Singapore Dent J, 1989 Dec;14(1):42-5.
    PMID: 2487475
    Mucoepidermoid tumours of the minor salivary glands of the tongue are rarely encountered. A case of a high-grade malignant type is reported here. Merits of subdivision of the mucoepidermoid tumour on the basis of its malignant potential are outlined, and variations of histological presentation of the present tumour at its primary and nodal sites are discussed.
  8. Ng KH, Gan SK
    Malays J Pathol, 1990 Jun;12(1):27-33.
    PMID: 2090887
    We investigated microwave-stimulated fixation of tissues for transmission electron microscopy using a domestic microwave oven operating at a frequency of 2.45 GHz with an output power of 500W. Microwave-stimulated fixation, in 4% glutaraldehyde, of fresh rat kidney, liver, heart and brain tissues was compared to conventional fixation. Human renal biopsies were similarly studied. Electron microscopy showed excellent ultrastructural preservation comparable to that obtained by conventional fixation. The optimal temperature range for microwave-stimulated fixation was found to lie between 50 degrees C and 55 degrees C. Our results indicate that microwave-stimulated fixation is a rapid and reproducible technique and can be effectively applied to routine diagnostic pathology.
  9. Siar CH, Ng KH
    J Laryngol Otol, 1991 Nov;105(11):971-2.
    PMID: 1722237
    A case is described of ameloblastoma of maxilla presenting with numerous calcified keratin pearls. The significance of cellular variation in relation to the behavioural potential of the ameloblastoma in general is briefly discussed.
  10. Ng KH, Siar CH
    Med J Malaysia, 1986 Sep;41(3):213-9.
    PMID: 2444865
    The morphology, incidence and distribution of hyaline cells in ten cases each of pleomorphic adenoma, adenoid cystic carcinoma, adenocarcinoma and mucoepidermoid tumour were studied by conventional light microscopy. Results showed that the hyaline cells were identified in 60% of pleomorphic adenoma and in 20% of mucoepidermoid tumours, but were absent in adenoid cystic carcinoma and adenocarcinoma. Relative area estimation of hyaline cells in pleomorphic adenomas showed that this may range from 2.2% to 30.4% of the total tumour area. The usefulness of the hyaline cell as a diagnostic criteria in distinguishing between some of the salivary gland tumours was also discussed.
  11. Ng KH, Peh WC
    Singapore Med J, 2009 Apr;50(4):330-4; quiz 335.
    PMID: 19421674
    In part two of "Preparing effective illustrations", the other three categories, viz. photographs, radiological images and diagrams, are discussed. Illustrations provide visual information to supplement the results in a scientific paper, and create a visual impact that can improve the readability of a paper. This article provides some basic guidelines to assist authors in preparing effective photographs, radiological images and diagrams.
  12. Ng KH, Peh WC
    Singapore Med J, 2009 Mar;50(3):245-9.
    PMID: 19352565
    Illustrations (also known as figures) are visual representations of the results obtained from a scientific study. Graphs are a common type of illustration that are often used in scientific papers to present information clearly and effectively, as well as to demonstrate relationships between variables in the data. Graphs also serve to reveal trends or patterns in the data. This article provides some basic guidelines to assist authors in preparing effective graphs for their papers.
  13. Ng KH, Peh WC
    Singapore Med J, 2009 May;50(5):458-60; quiz 461.
    PMID: 19495512
    The discussion section comprises the last component in the IMRAD system. The purpose of this section is to provide the interpretation of the results obtained, explain the implications of the findings, state study limitations and make suggestions for future research. This is a critical part of the scientific paper, as it places the particular study within the broader context of how the research contributes to improving diagnosis, treatment or patient care.
  14. Ng KH, Peh WC
    Singapore Med J, 2009 Dec;50(12):1134-7; quiz 1138.
    PMID: 20087547
    After submission and acceptance of a scientific paper by a journal, the final stages in the publishing process are copy-editing and proofreading. The primary purpose of this step is to ensure accurate and quality production of scientific papers. Authors are responsible for checking their proofs properly and in detail, ensuring that everything is correct as this is their last chance to make any changes before their work is set in print forever.
  15. Ng KH, Peh WC
    Singapore Med J, 2010 Oct;51(10):757-60; quiz 761.
    PMID: 21103809
    A bibliographic database is an organised digital collection of references to published literature. A bibliographic database may be general in scope or may cover a specific academic discipline. There are many types of medical and general bibliographic databases. They cover biomedical and scientific literature, morbidity and mortality statistics, therapeutic regimens, medical records, images and reviews of evidence-based medicine. Getting to know these databases will help researchers and authors to enhance their writing and publishing endeavours.
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links