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101.
Epidemiology is emerging as a promising tool for understanding and interpreting diseases in all dimensions and identifying levels of intervention for their control or eradication. Coupled with the discipline of health administration and management, epidemiology can offer viable and pragmatic solutions for tackling disease problems. Eradication of small pox in the recent past and the formulation of a strategy for the control of the modern epidemic of AIDS are 2 best known examples. An epidemiological approach to acute respiratory tract infection (ARI) in children can improve the understanding of the disease and help to prepare the ground for effective control. The principal areas of epidemiology are natural history, intervention strategy, and epidemiological inquiry. The principal viruses that have been identified to lead to ARI infection on the basis of systematic studies are rhinoviruses (100 different serotypes), parainfluenza viruses (several serotypes), respiratory syncytial virus, adenoviruses (about 8 important serotypes in children), enteroviruses (ECHO and Coxsackie with more than 70 serotypes), herpes simplex virus, measles virus, and Epstein-Barr virus. Based on the natural history of ARI, the scope of application of the 5 levels of intervention may be discussed individually as health promotion, specific protection, early diagnosis and prompt treatment, disability limitation, rehabilitation, and epidemiological inquiry. Epidemiological techniques may contribute substantially to the understanding and management of ARI control by: a) defining the ARI problem and its magnitude and behavior in relation to time, place, and person; b) identifying the epidemiological correlates of ARI in terms of agent, host, and environment, and their impact on morbidity and mortality in children; c) introducing epidemiological surveillance and monitoring techniques for effective supervision of intervention activities; and d) conducting longitudinal observational studies to evaluate efficiency and effectiveness of various intervention alternatives for ARI control.  相似文献   
102.
Intravenously administered oxytocin caused a dose-related fall in blood pressure of the rabbit. When oxytocin was administered in oestrogen-primed animals, the depressor response was converted to a pressor one "Oxytocin reversal". The "oxytocin reversal." was abolished after treatment with dihydroergotamine, hexamethonium or adrenalectomy. The "oxytocin reversal" did not appear in reserpinized animals.  相似文献   
103.
Management of Head and Neck Cancers poses a challenge inspite of several advances because of poor success in terms of response rate, survival and reduced morbidity of the patients. In the present study 30 untreated histologically proven cases of head and neck cancers were subjected to weekly radiotherapy with adjuvant chemotherapy (cisplatin 30 mg/m2 intravenously). This study group was compared with a group of 30 patients who were given only radiotherapy. Results have shown that combination of chemotherapy with radiotherapy gives a significantly better results in tumour as well as nodal response with minimal toxicities.  相似文献   
104.
Seventy-eight patients (85 affected hips and 71 unaffected hips) with Legg-Calvé-Perthes disease were included in this study to evaluate the metaphyseal change in radiographs and magnetic resonance imaging (MRI) and to define the type of the metaphyseal cyst according to presence or absence of the epiphyseal involvement. The content of the metaphyseal cyst was evaluated by using T1,T2, proton, and gadolinium-enhanced T1-weighted MRI scans. Among 85 hips, there were no changes in 32 hips, marrow edema in 13 hips, false cyst with epiphyseal involvement in 28 hips, and true cyst without epiphyseal involvement in 12 hips. Granulation tissue was found in the false cysts and water-rich fibrotic tissue was found in the true cysts based on the MRI scans. The metaphyseal change in MRI scans was shown in 71% of groups 3 and 4 and in 35% of groups 1 and 2 according to the Catterall classification, and 52% of group A, 56% of group B, and 86% of group C according to the Herring classification. Of the 30 hips at the avascular stage, 33% showed metaphyseal cyst in MRI scans. Of the 53 hips at the fragmentation stage, 60% showed the metaphyseal cyst.  相似文献   
105.
PURPOSE: Angiogenesis plays an important role in a multitude of biological processes including those of tumorigenesis and cancer progression. Hypoxia is the prime driving factor for tumor angiogenesis and the family of hypoxia-inducible factors (HIFs) plays a pivotal role in this process. The role of HIF in tumor angiogenesis has been underscored in different carcinomas but yet to be reported for colorectal carcinomas. EXPERIMENTAL DESIGN: In this study, we examined HIF [HIF-1alpha (HIF1) and HIF-2alpha (HIF2)] expression in 87 curatively resected colorectal carcinoma samples, and the results were correlated with clinicopathological factors, microvessel density, cyclooxygenase 2 expression, and patient prognosis. RESULTS: HIF1 (44.8%) was more frequently expressed than HIF2 (29.9%). Most of the clinicopathological factors representing the tumor aggressiveness were significantly correlated with overexpression of HIF2 but not with HIF1 expression. HIF2 expression had direct correlation with microvessel density and cyclooxygenase 2 expression. and, in contrast, HIF1 expression had a weak but significant inverse correlation in T1 and T2 tumors only. HIF2 expression alone and the combined expression of HIF1 and HIF2 had significant impact on patient survival. In the multivariate analysis, however, only the combined expression of HIF1 and HIF2 remained independently significant. CONCLUSIONS: Taken together, our results suggest that HIF2 expression may play an important role in angiogenesis and that the combined expression of HIF1 and HIF2 may play an important role in tumor progression and prognosis of colorectal carcinomas. Therefore, HIF expression could be a useful target for therapeutic intervention.  相似文献   
106.
Studies from our laboratory have indicated skin cancer chemopreventive effectsof sandalwood oil in CD-1 mice. The purpose of this investigation was to study the skin cancer chemopreventive effects of alpha-santalol, a principal component of sandalwood oil in CD-1 and SENCAR mice. alpha-Santalol was isolated from sandalwood oil by distillation under vacuum and characterized by nuclear magnetic resonance and gas chromatography-mass spectrometry. Chemopreventive effects of alpha-santalol were determined during initiation and promotion phase in female CD-1 and SENCAR mice. Carcinogenesis was initiated with 7,12-dimethylbenz(a)anthracene and promoted with 12-O-tetradecanoylphorbol-13-acetate (TPA). The effects of alpha-santalol treatment on TPA-induced epidermal ornithine decarboxylase (ODC) activity and (3)H-thymidine incorporation in epidermal DNA of CD-1 and SENCAR mice were also investigated. alpha-Santalol treatment during promotion phase delayed the papilloma development by 2 weeks in both CD-1 and SENCAR strains of mice. alpha-Santalol treatment during promotion phase significantly (P < 0.05) decreased the papilloma incidence and multiplicity when compared with control and treatment during initiation phase during 20 weeks of promotion in both CD-1 and SENCAR strains of mice. alpha-Santalol treatment resulted in a significant (P < 0.05) inhibition in TPA-induced ODC activity and incorporation of (3)H-thymidine in DNA in the epidermis of both strains of mice. alpha-Santalol significantly prevents papilloma development during promotion phase of 7,12-dimethylbenz(a)anthracene-TPA carcinogenesis protocol in both CD-1 and SENCAR mice, possibly by inhibiting TPA-induced ODC activity and DNA synthesis. alpha-Santalol could be an effective chemopreventive agent for skin cancer. Additional experimental and clinical studies are needed to investigate the chemopreventive effect of alpha-santalol in skin cancer.  相似文献   
107.
108.
Depression is probably the most common psychiatric disorder in women. Women are a vulnerable group of depression due to psychological, social and biological factors. Marital relationships, social support, roles and self esteem are factors that contribute to depression. In addition, several periods in women's life relating to the reproductive cycle are periods of increased vulnerability. Management of depression in women should consist of detailed assessment of all the above factors. Drug treatment of depression in women requires an in depth understanding of pharmacokinetics of the drugs used and possible drug interactions. Treatment of depression in women should integrate both psychosocial and biological treatment modalities.  相似文献   
109.
Imaging spectrum in sclerotic myelomas: an experience of three cases   总被引:2,自引:0,他引:2  
Grover SB  Dhar A 《European radiology》2000,10(11):1828-1831
The classic radiographic presentation of multiple myeloma is lytic skeletal lesions. Primary sclerotic manifestations are rare and occur only in 3 % of cases. The imaging spectrum in three cases of multiple myeloma with primary osteosclerosis is described. The first patient had spiculated sclerosis of the orbit, which is an uncommon site for myeloma. The second patient with POEMS syndrome had multiple, scattered, skeletal lesions with sclerotic margins. The third patient presented with a chest wall mass and had an expansile thick spiculated sclerosis in the rib. The wide imaging spectrum possible in sclerotic myelomas and their relevant differential diagnosis is emphasized. Received: 14 March 2000; Accepted: 25 April 2000  相似文献   
110.
A prospective longitudinal study was conducted on fifty patients of histopathologically confirmed head and neck cancer with the main aim to assess the nasal mucociliary clearance, pre-and post-irradiation; and to compare the findings with the healthy non-irradiated age and sex-matched controls. All the patients underwent saccharin particle test for nasal mucociliary clearance before commencement of radiation therapy and again within 6 months of completion of radiation therapy. The difference between the saccharin perception times of nasal mucosa in the healthy non-irradiated controls and the pre-irradiated head and neck cancer patients were statistically inssignificant (P>0.05). But, the difference between the saccharin perception times of nasal mucosa in the pre-and post-irradiated head and neck cancer patients was found to be statistically significant (P=0). It is concluded that even indirect irradiation of nasal mucosa in head and neck cancer patients significantly affect its ciliary activity. Significance of total radiation dosage along with chemotherapy in some cases was also studied.  相似文献   
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