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11.
Aims of the present paper was to study cell death by apoptosis and cell proliferation in normal cervical biopsies, cervical intraepithelial neoplasms (CIN) and squamous cell carcinomas of cervix (CaCx). There were each seven cases of normal cervical biopsy, CIN1 and CIN2 along with 10 cases of CIN3 and 14 cases of CaCx. Percentage of apoptotic cells and bodies (i.e. apoptotic index, AI) and mitoses (i.e. mitotic index, MI) and turnover index (TI - AI + MI) were counted in formalin fixed, paraffin embedded, haematoxylin and eosin stained slides. AgNOR stain was done and mean AgNOR dots per cell was also estimated. AI, MI and TI were correlated with histology grade of CIN and invasive carcinoma cervix. Mean AI, MI, TI and AgNOR count increased from lower to higher grades of CIN. AI, MI & TI raised significantly from CIN3 to carcinomas; AI, TI & AgNOR count raised significantly from CIN1 to combined CIM2 & 3; TI & AgNOR count were high in CIN1 to CIN2; AI & TI were significantly raised in normal to CIN1. In conclusion, TI is probably more important for cell kinetic analysis of CIN and carcinoma of cervix because it reflects the frequency of two important events i.e. mitosis and cell death. Sudden increase of AI, MI, TI count from CIN3 to CaCx may indicate the possibility of genetic alteration of cells of CIN3 which induces a frank malignant transformation from CIN3 to CaCx. 相似文献
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A state-operated residential facility has for the past five years been using performance feedback as the primary method for improving direct care staff interactions with clients. The major problem with this approach is determining when staff performance is significantly above or below average. Statistical process control charts are being used to determine whether variations in staff performance are the result of common or special causes. Analysis of staff performance for one year suggests that variation in staff performance may be due to special causes, such as the characteristics of the clients served and the type of service that is provided to these clients. Services were adapted to the characteristics of these clients, which improved staff performance and reduced variation. 相似文献
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Vasculogenesis was simultaneously studied with embryogenesis in in ovo chick embryo culture, which was harvested at 40 hours. Endodermal cells and vascular endothelial cells were studied using a new combination of stains, immunohistochemistry (for nuclei and basement membrane) and NADPH-diaphorase activity in whole-mounts, paraffin sections and etched semithin sections. The model can be used for the study of developmental process of blood vessels as well as embryonic physiology of blood vessels vis-a-vis organogenesis in response to different angiogenic agents, drug trials, cancer therapy by angiostatic chemicals/radiations and toxins. Considering that vasculogenesis/angiogenesis as one of the fundamental phenomena in physiology, pathophysiology, toxicology and pharmacology of developmental sciences, the model in developing embryo is presented. 相似文献
16.
Dynamic SPECT imaging of dopamine D2 receptors in human subjects with iodine-123-IBZM. 总被引:6,自引:0,他引:6
J P Seibyl S W Woods S S Zoghbi R M Baldwin H M Dey A W Goddard Y Zea-Ponce G Zubal M Germine E O Smith 《Journal of nuclear medicine》1992,33(11):1964-1971
We studied the uptake, distribution, metabolism and washout of the dopamine D2 receptor ligand [123I]IBZM in healthy subjects (n = 12) with dynamic brain SPECT. The highest radioactivity level was detected in the striatum. Operationally-defined striatal "specific" uptake peaked at 69 min postinjection of radioligand and showed a gradual decline of 15% per hour thereafter. "Specific" uptake at maximal counts represented 53% of the total striatal radioactivity. Two subjects received haloperidol (20 micrograms/kg i.v.) 80 min postinjection of radioligand. Haloperidol caused a 2.6-fold increase in the rate of washout of specific striatal activity in comparison to that in the 10 control subjects and was consistent with drug-induced displacement of radioligand from the dopamine D2 receptor. Two classes of metabolites were detected in plasma and urine: a polar fraction, not extracted by ethyl acetate, and a nonpolar, extractable fraction consisting of parent compound and two compounds having shorter retention times on reversed-phase HPLC. Greater than half the plasma parent was metabolized within 10-15 min after administration. The volume of distribution, estimated from the peak arterial plasma concentration at 50-75 sec, was 7.7-10.2 l; the free (nonprotein bound) fraction of [123I]IBZM after in vitro incubation with blood or plasma was 4.4% +/- 0.4%. These results suggest that [123I]IBZM exhibits uptake in brain regions with high D2 receptor density and shows a relatively stable washout during which drugs affecting dopaminergic transmission may be administered. 相似文献
17.
B J Jha S Dey M D Tamang M E Joshy P G Shivananda K N Brahmadatan 《Kathmandu University Medical Journal》2006,4(3):290-294
Objectives: (1) To identify and characterize the Candida species isolates from lower respiratory tract infection. (2) to determine the rate of isolation of Candida species from sputum samples. Methods: This study was carried out in the Department of Microbiology, Manipal Teaching Hospital, Pokhara, Nepal from June 2002 to January 2003. A total of 462 sputum samples were collected from patients suspected lower respiratory tract infection. The samples were processed as Gram staining to find out the suitability of the specimen, cultured on Sabouraud's Dextrose Agar (SDA) and also on blood agar and chocolate agar to identify the potential lower respiratory tract pathogens. For the identification of Candida, sputum samples were processed for Gram stain, culture, germ tube test, production of chlamydospore, sugar fermentation and assimilation test. For the identification of bacteria, Gram stain, culture, and biochemical tests were performed by standardized procedure. Result: Out of 462 samples, 246 (53.24%) samples grew potential pathogens of lower respiratory tract. Among them Haemophilus influenzae 61(24.79%) and Streptococcus pneumoniae 57 (23.17%) were the predominant bacterial pathogens. Candida species were isolated from 30 samples (12.2%). The majority of Candida species amongst the Candida isolates were Candida albicans 21(70%) followed by Candida tropicalis 4(13.33%). Candida krusei 3(10%), Candida parapsilosis 1(3.33%) and Candida stellatoidea 1(3.33%). The highest rate of isolation of Candida was between the age of 71 and 80. Conclusion: Candida isolation from sputum samples is important as found in the present study in which Candida species were the third most common pathogen isolated from patients with lower respiratory tract infection. Key words: Candida albicans, Pulmonary candidiasis, Nepal. 相似文献
18.
Sourav De Ashok Kumar S K Suraj Kumar Shah Sabnaz Kazi Nandan Sarkar Subhasis Banerjee Sanjay Dey 《RSC advances》2022,12(24):15385
The nitrogen-bearing heterocycle pyridine in its several analogous forms occupies an important position as a precious source of clinically useful agents in the field of medicinal chemistry research. This privileged scaffold has been consistently incorporated in a diverse range of drug candidates approved by the FDA (Food and Drug Administration). This moiety has attracted increasing attention from several disease states owing to its ease of parallelization and testing potential pertaining to the chemical space. In the next few years, a larger share of novel pyridine-based drug candidates is expected. This review unifies the current advances in novel pyridine-based molecular frameworks and their unique clinical relevance as reported over the last two decades. It highlights an inclination to the use of pyridine-based molecules in drug crafting and the subsequent emergence of several potent and eligible candidates against a range of diversified diseases.The nitrogen-bearing heterocycle pyridine in its several analogous forms occupies an important position as a precious source of clinically useful agents in the field of medicinal chemistry research. 相似文献
19.
A sandwich structure is a composite material consisting of thin skins encapsulating a cellular core. Such structures have proven to be excellent energy absorbents and are frequently found in various types of protection. Even so, few studies exist in the open literature on the response of the core material itself under extreme loadings such as blast and impact. Since a blast load is usually accompanied by numerous fragments, it is important to understand and be able to predict the ballistic impact resistance of the often highly inhomogeneous cellular core materials in design. In this study, the ballistic impact response of an aluminium foam with a complex cell structure has been investigated both experimentally and numerically. First, an extensive material test program involving compression tests on cubic specimens loaded in the thickness direction of the foam was carried out to reveal the mechanical properties of the material. In addition, several of the specimens were scanned before testing using X-ray Micro Computed Tomography (XRMCT) to map the multi-scale topology and morphology of the material. These data were later analysed to extract density-variation plots in many different material orientations. Second, ballistic impact tests were conducted using a gas gun where rigid spheres were launched towards aluminium foam plates, and the ballistic limit velocity and curve of the foam material were established. Finally, numerical simulations of both the material tests and the ballistic impact tests were carried out using LS-DYNA and different modelling approaches based on the XRMCT data. It will be shown that, independent of the modelling strategy applied, good agreement between the experimental impact tests and the numerical predictions can be obtained. However, XRMCT data are important if the final goal is to numerically optimise and improve the behaviour of inhomogeneous foams with respect to energy absorption, thermal isolation, or similar properties. 相似文献
20.
Sultana A Zakaria SM Bhuiyan SI Habib A Dey SK Rahman M Basher A 《Mymensingh medical journal : MMJ》2012,21(3):529-532
Post-kala-azar dermal leishmaniasis (PKDL) is a complication of visceral leishmaniasis (VL) and serves as a potential reservoir for Leishmania parasite. The study was aimed to evaluate the spectrum of skin lesions of PKDL in kala-azar endemic areas in Bangladesh. This cross sectional study was carried out to observe the characteristics of skin lesions among 250 PKDL cases. The suspected PKDL patients in highly endemic villages of Fulbaria Upazilla of Mymensingh district.were subjected to a dipstick test (rK39) for kala azar. The median time interval between diagnosing kala-azar and PKDL was 23 month (m-21, r- 0-60 months). The most common skin lesions were multiple symmetrical hypopigmented macules with irregular margins in 179(71.6%) cases followed by erythematous facial induration in 74(29.6%), papular in 33(13.2%), nodular in 28(11.2%) cases, combination of macules, papules, nodules and plaques in 88(35.2%) cases, annular in 7(2.8%) cases and Papillomatous mucosal growth in 2(0.8%) cases. Sites of involvement were mostly in face (92.4%), Trunk (84.8%), extremities (33.2%), oral mucosa and tongue (0.8%) and Genitalia (1.2%). Suspicion of PKDL on the basis of skin lesions will lead to early diagnosis and prompt treatment will impart an important role in prevention and eradication of Leishmaniasis in Bangladesh. 相似文献