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51.
The Oral HIV/AIDS Research Alliance (OHARA) is part of the AIDS Clinical Trials Group (ACTG), the largest HIV clinical trials organization in the world. Its main objective is to investigate oral complications associated with HIV/AIDS as the epidemic is evolving, in particular, the effects of antiretrovirals on oral mucosal lesion development and associated fungal and viral pathogens. The OHARA infrastructure comprises: the Epidemiologic Research Unit (at the University of California San Francisco), the Medical Mycology Unit (at Case Western Reserve University) and the Virology/Specimen Banking Unit (at the University of North Carolina). The team includes dentists, physicians, virologists, mycologists, immunologists, epidemiologists and statisticians. Observational studies and clinical trials are being implemented at ACTG-affiliated sites in the US and resource-poor countries. Many studies have shared end-points, which include oral diseases known to be associated with HIV/AIDS measured by trained and calibrated ACTG study nurses. In preparation for future protocols, we have updated existing diagnostic criteria of the oral manifestations of HIV published in 1992 and 1993. The proposed case definitions are designed to be used in large-scale epidemiologic studies and clinical trials, in both US and resource-poor settings, where diagnoses may be made by non-dental healthcare providers. The objective of this article is to present updated case definitions for HIV-related oral diseases that will be used to measure standardized clinical end-points in OHARA studies, and that can be used by any investigator outside of OHARA/ACTG conducting clinical research that pertains to these end-points.  相似文献   
52.
Routine semen examination remains an important tool for the diagnosis and treatment in human subfertility. Of all semen parameters, sperm morphology seems to be one of the most powerful indicators of a man's fertilizing potential in vitro and in vivo. Lack of standardization of sperm morphology assessments remains the main reason for the usefulness of this parameter. The aim of this study was to analyze the agreement between the wet-stained preparations versus those stained with modified Diff-Quik for sperm morphology. A total of 100 unselected semen samples from infertile couples were analyzed. Sperm morphology was evaluated with unstained specimens and following modified Diff-Quik staining according to the strict (Kruger classification) criteria by two different examiners (intralaboratory blind assessment). Mean percentages of morphologically normal spermatozoa were identical on wet and stained preparation slides (4.79 vs. 4.61, p >.05). Wide divergence of results was found with respect to the percentage of sperm with head and midpiece defects with the two different preparations (p >.001). The percentage of sperm tail defects was similar in both methods (p >.05). Simple linear regression analysis between the two methods revealed very good correlation for the morphologically normal spermatozoa (r =.83), but poor correlation for the sperm head, midpiece, and tail defects (r =.25,.25, and.28, respectively). Wet preparation is suitable only for the morphologically normal spermatozoa, but to determine the percentage of the defective spermatozoa, staining the smear is recommended.  相似文献   
53.
Inhibition of bacterial growth by lignocaine in propofol emulsion   总被引:1,自引:0,他引:1  
Contamination of propofol, in an emulsion formulation, has been associated with infective complications. Local anaesthetics,some of which are known to have antibacterial properties, are frequently added to the solution to reduce pain on injection. We examined the growth rates of E. coli, S. aureus, S. epidermidis and P. aeruginosa in propofol with and without lignocaine 0.1%-2% after incubation for 2, 5 and 24 hours at 37 degrees C. Growth of microorganisms in each solution was compared by counting the number of colony forming units (CFU). Propofol supported the growth of all microorganisms. An increase in the number of CFUs was observed in all drug combinations 2, 5 and 24 hours after inoculation except for S. aureus (P<0.05). No difference was found in CFU numbers between 2 and 5 hours for this microorganism. With E. coli, a significant decline in colony counts was observed in mixtures of 1% and 2% lignocaine (P<0.05). With the other microorganisms only 2% lignocaine showed a significant reduction in the number of CFUs (P<0.05). We conclude that lignocaine in recommended clinical doses (0.05%-0.1%) did not exhibit adequate antibacterial activity to prevent infective complications.  相似文献   
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目的:探讨颅骨牵张术修复骨缺损过程中新骨骨密度的评价方法。方法:成年健康山羊18只,颅顶区制备25mm×10mm全层颅骨缺损,随机分为实验组和对照组,实验组15只建立牵张术修复颅骨缺损的动物模型,于牵张结束后2,4,6周分别处死5只动物,对照组3只动物与实验组牵张后6周动物同期处死,QCT、DEXA两种方法测量新骨骨密度,比较两种测量方法骨密度值(BMD)及相关性。结果:实验组QCT测量牵张间隙各兴趣区BMD值较前一时段对应BMD值明显增加(P<0.05),同一牵张间隙内各固定时段两端(R2、R3)较中央(R1)BMD值明显高(P<0.05),R2、R3之间无明显差别(P>0.05);DEXA测量固定期4周,各兴趣区BMD值较固定2周对应BMD值明显增加(P<0.05),而固定期6周,仅牵张间隙中央(R1)较固定4周对应BMD值增加有统计学意义(P<0.05),同一牵张间隙内固定期2,4周两端(R2、R3)较中央(R1)BMD值明显高(P<0.05);两种检测方法测得平均骨密度值在各时段均存在正相关(P<0.005);对照组缺损区QCT、DEXA检测未显示有新骨形成。结论:两种检测方法均能反映牵张过程新骨骨密度变化,QCT不受解剖结构和牵张器形状的影响,更适于颅面骨牵张术新骨形成的监测评价。  相似文献   
57.
环肺静脉消融治疗慢性房颤   总被引:10,自引:0,他引:10  
背景:进行一项关于环肺静脉消融治疗慢性房颤的随机对照试验。方法:共纳入146例年龄为57±9岁的慢性房颤患者,将其随机分人头3个月仅接受胺碘酮及两次心脏复率治疗组(对照组)或联合环肺静脉消融治疗组。每天通过电话联系以评估心脏节律,共持续1年。在12个月时评估左房直径和症状严重程度。结果:77例接受环肺静脉消融术的患者中,26%因房颤复发再次行消融治疗,6%因非典型房扑而再次行消融治疗。意向治疗分析显示,在未服用抗心律失常药物的情况下,1年内消融组74%的患者和对照组58%的患者未出现房颤复发或房扑(P=0.05)。在对照组的69例患者中,1年内有53例(77%)因房颤复发转而行环肺静脉消融治疗,仅有3例(4%)在不服用抗心律失常药物且未行消融术的情况下维持窦性节律。  相似文献   
58.
Tularemia is a zoonotic disease caused by the coccobacillus F. tularensis. Small epidemics and sporadic cases were seen around Bursa since November 1988. In this study, a total of 205 cases of tularemia were observed. All the cases were diagnosed on clinical, bacteriological and serological grounds. The epidemics were thought to be waterborne. The majority of the patients were young and female. In most of the cases the disease presented itself in oropharyngeal form (83%). Analysing sera from the patients with microagglutination method demonstrated that titers were 1:160 in approximately 85% of the cases, including the ones in subclinical form. Five of ten patients from who the bacteria was isolated were seronegative. Streptomycin was given to the most of the patients by combining with tetracycline, doxycycline or chloramphenicol. The early administration of these antibiotics (before the third week of disease) was found to be much more effective to resolve the infection. As a result, the main mode of transmission of F. tularensis is waterborne in our region. In our region, tularemia should be considered in differential diagnosis for the cases with fever, tonsillopharyngitis and cervical lymphadenopathy to make an early diagnosis and to design relevant treatment.  相似文献   
59.
OBJECTIVE: To determine the incidence of late-onset congenital adrenal hyperplasia (LOCAH) due to 21-hydroxylase deficiency among hirsute women and to evaluate the results of the ACTH stimulation test with the clinical characteristics. STUDY DESIGN: Prospective, controlled study. One hundred women with hirsutism and 14 normally cycling women without hirsutism were included in this study at the Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Cerrahpasa School of Medicine, Istanbul University. After basal serum progesterone (P) and 17 hydroxyprogesterone (17OHP) levels were determined, an ACTH stimulation test was performed on cycle day 3-5. The same parameters were checked 30 minutes later. We estimated the 21 hydroxylase activity by calculating the change in 17OHP (17OHP 30-0) and the summed rate of the change in P and 17OHP ([P30-0] + [17OHP30-01/30 minutes). The 95th percentile for these estimates in normal women were calculated, and values above three times the 95th percentile were considered to distinguish women with LOCAH due to 21-hydroxylase deficiency. RESULTS: The 95th percentile for 17OHP 30-0 and (P30-0) + (17OHP30-0)/30 minutes in normal women was 1.6 and 8.9 ng/dL/min, respectively. Regarding 17OHP 30-0 values, three women with hirsutism had levels above three times the 95th percentile of these estimates, and 28 women had estimates of more than the 95th percentile but less than threefold. Seventeen of 28 women had oligomenorrhea, and all had severe hirsutism. The women with severe hirsutism and oligomenorrhea had significantly higher ACTH-stimulated serum 17OHP levels and values for 17OHP 30-0 and (P30-0 + (17OHP30-0)/30 min) than did normally cycling women. CONCLUSION: The incidence of LOCAH due to 21-hydroxylase deficiency and mild 21-hydroxylase deficiency is 3% and 28%, respectively, in women with hirsutism. Clinical characteristics are not helpful in determining 21-hydroxylase deficiency. However, the incidence of 21-hydroxylase deficiency is more common among women with severe hirsutism and oligomenorrhea. The change in serum 17OHP 30-0 seems to be greater than the summed rate of change in serum 17OHP and P in the detection of 21-hydroxylase enzyme deficiency.  相似文献   
60.
The value of serum Bcl-2 levels in advanced lung cancer patients   总被引:2,自引:0,他引:2  
Overexpression of the Bcl-2 protein was associated with a favorable prognostic factor for survival in lung cancer patients, especially nonsmall cell lung carcinoma. The present study was conducted to investigate the value of serum Bcl-2 levels in advanced lung cancer patients. Fifty patients with advanced lung carcinoma pathologically verified and 18 healthy controls were investigated. Serum samples were obtained on the first admission before the chemotherapeutic treatment were given. Serum Bcl-2 levels were determined by using anti-Bcl-2 monoclonal coating antibody. The baseline serum Bcl-2 levels were significantly higher in patients with lung cancer than in the control group (p<0.001). Serum Bcl-2 levels were elevated in 48 (96%) advanced lung cancer patients. None of the prognostic parameters analyzed, such as age of patient, gender, histology, stage of disease, erythrocyte sedimentation rate, serum albumin, hemoglobin, CEA, NSE, LDH, performance of patient, weight loss, and response to chemotherapy, was significantly correlated with Bcl-2 serum concentrations. The serum Bcl-2 concentrations were not changed with cisplatin-based cytotoxic chemotherapy regardless of response (p=0.76). No prognostic value of serum Bcl-2 was determined. In conclusion, the results of the present study, which is the first study to determine serum Bcl-2 levels in lung cancer, suggest that decreased apoptosis occurred due to the effect of serum Bcl-2 elevation in lung cancer patients. Serum Bcl-2 level was of diagnostic but not prognostic value in lung cancer patients. However, more studies are needed to define the role of Bcl-2 in the diagnosis and prognosis of lung cancer.  相似文献   
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