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61.
62.
OBJECT: Several patterns of fetal breathing movements (FBMs), i.e. abdominal wall movements (AWm), thoracic wall movements (TWm) and nasal fluid flow velocity waveforms (NFFVW), were investigated by ultrasound (US) technology and related to fetal pulmonary maturity and immaturity, i.e. fetal lung maturity (FLM) tests, in order to validate the hypothesis that they may indicate whether the fetal lung is mature or immature, regardless of gender, weight and gestational age. MATERIAL AND METHODS: We prospectively enrolled 143 high-risk pregnancies in which a complete US study of FBMs and FLM tests was performed. Among them 43 women satisfied the inclusion criteria. US-FLM was defined as the presence of regular NFFVW detected by pulsed Doppler and spectral analysis, or irregular NF-FVW synchronous with TWm detected by M-mode. An US guided amniocentesis was performed in order to collect amniotic fluid (AF) and FLM was evaluated by L/S (lecithin/sphingomyelin) determination, presence of phosphatidylglycerol (PG) and lamellar bodies (LBs) count. At the end of the study the diagnostic accuracy of US-FLM was compared to that of FLM tests. RESULTS: Diagnostic accuracy for US evaluation of FLM was as follows: sensitivity: 89.6%; specificity: 85.7%; PPV: 92.8%; NPV: 80%. Diagnostic accuracy of FLM tests was as follows: sensitivity: 100%; specificity: 51.7%; PPV: 100%; NPV: 50%. L/S determination predicted lung maturity with a sensitivity of 100%; specificity of 93.1%; PPV of 100%; NPV of 87.5%. CONCLUSION: Presence of regular NFFVW or irregular NFFVW and TWm correlate accurately with conventional FLM tests. We suggest that this noninvasive procedure may be helpful for assessing FLM, particularly under certain circumstances, e.g., oligo-anhydramnios, laboratory logistic equipment difficulties or heavily stained AF samples, amniocentesis refusal, religious concerns.  相似文献   
63.
Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections (STIs) in young women. They can occur in one or multiple areas of the female genitalia. Usually, the vulva is the initial site of implantation for HPV. The purpose of our study is to evaluate the epidemiological aspects, incidence of single or multiple lesions in the lower genital tract, correlation between sexual behaviour and their localization and behaviour risk factors for persistence and recurrence of HPV lesions and cervical intraepithelial lesion (CIN) in a long-term follow-up among young women. We recruited 268 patients aged 11-21 years who previously had cytology and/or physical examination suspicious for HPV infection. The women were interviewed and asked information about lifestyle, sexual behaviour, work, personal or family history of genital warts and school attendance. We considered individuals to be 'smokers' if they smoked more than five cigarettes/day. No specific data were recorded about oral contraception, nevertheless, no woman had used oral contraceptives (OCs) for more than 2 years. Young women included in the study were between the age of 12 and 21 years who had HVP lesions after entry examinations and had undergone no treatment for HPV lesions prior to entry. Other exclusion criteria relevant to this study included cervical excisional treatment prior to entry or later. Two hundred and thirty-four young women were included in our study group. Our diagnostic schedule for a complete evaluation included exo- and endocervical cytology, colposcopy, directed biopsy and microcolpohysteroscopy. The treatment was performed with a LASER CO2 Coherent 400, model 451, with Zeiss photocolposcopy attachment.The finding that, among 126/234 (53.8%) adolescents using contraceptives, only 85 (36.3%) have used condom, the only barrier form of contraceptive effectively protecting against virus, shows a low awareness of the high risk for contracting HPV infection among young sexually active women. The sites most frequently affected in our study were vulva, perianus and perineum (194/234), 82.9% and the cervix (125/234), 53.4%. Vaginal lesions were detected only in 29/234 patients (12.3%). According to our data, in 161 patients, sexual habits, age at the first intercourse (P=0.68), frequency of intercourses (P=0.49) and number of lifetime partners (P=0.27) as well as age (P=0.26) play a role in transmission and incidence of HPV infection but not on the location of the lesions. This can be due to a coexistent clinical and subclinical multiple infection as well as a transmission via intercourse or from other sources, including tampons. Abnormal Pap test was related to HPV infection, but the low correlation with colposcopic and histological findings in this study justify the support of other examinations such as colposcopy and punch biopsy for diagnosis. Moreover, according to our data, cytology alone shows to be not suitable to exclude CIN (seven underestimated cases of CIN) and a closer correspondence were found between colposcopy and the result of histological sample after punch biopsy in CIN detection. More attention must be paid to psychological aspect of diagnoses and treatment among adolescents, more than older women as the high rate of patients lost shows in our study: 75/234 (32.05%) before LASER surgery and 55/159 (34.59%) during follow-up. International data shows that only 12-45% of sexually active adolescent girls have obtained Pap smear screening. In our study, we found no correlation between treatment failure and cigarette smoking or between the use of oral contraceptives and persistence/recurrence after LASER CO2 surgery. Because the small sample of our study group, further analyses were required.  相似文献   
64.
Acetowhitening of the vulva has been related to a subclinical human papillomavirus (HPV) infection. No consense has been reached about undertaking -or not- any therapy for these acetowhite changes. We have observed from our clinical experience and in a 10 years observational follow-up, that acetowhitening of the vulva regarding high risk (16-18) and low risk (6-11) HPV groups (as assessed by PCR analysis) significantly decreased; and acetowhitening areas negative to polymerase chain reaction (PCR), significantly increased from 53% (202/382) to 85% (276/325) (P<0.001). Our findings suggest that independently from HPV type and in the absence of cofactors, there is a statistically significant spontaneous remission of these areas.  相似文献   
65.
甲硝唑葡萄糖注射液细菌内毒素检查法的研究   总被引:1,自引:0,他引:1  
目的;以细菌内毒素检查法对甲硝唑葡萄糖注射液进行试验研究。方法;采用抑制或增强试验,并将细菌内毒素检查法与家兔法检测结果作对比。结果:该注射液经一定稀释后对测定无干扰。结论:细菌内毒素检查法适用于检测该注射液。  相似文献   
66.
67.
SUMMARY A young patient presenting with splenomegaly and hypersplenism was inadvertently found to have selective IgA deficiency. There were no symptoms of immunodeficiency and the patient responded well to splenectomy, with return of blood counts to normal without adverse effects. No other cause for the hypersplenism was found. We postulate selective IgA deficiency as a cause of splenomegaly and hypersplenism.  相似文献   
68.
恶性肿瘤淋巴管生成与转移的研究进展   总被引:1,自引:0,他引:1  
张海娥  庄建基  杨帆 《医学争鸣》2007,28(5):479-480
淋巴道转移是肿瘤转移的重要途径,也是判断预后的重要依据. 随着淋巴管生成因子及许多淋巴管特异性标记物的发现,肿瘤新生淋巴管调控与淋巴道转移机制研究得以深入开展. 大量的研究发现,恶性肿瘤和瘤周组织内存在新生的淋巴管,新生的淋巴管密度和淋巴管标记物的表达强度均与淋巴结转移密切相关. 这为揭示恶性肿瘤淋巴道转移机制和开发淋巴管靶向治疗提供了重要的研究途径. 现就近年来肿瘤淋巴管生成与转移的研究进展作一综述.  相似文献   
69.
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium.  相似文献   
70.
Sanfilippo B syndrome is caused by a deficiency of alpha-N- acetylglucosaminidase, a lysosomal enzyme involved in the degradation of heparan sulphate. Accumulation of the substrate in lysosomes results in degeneration of the central nervous system with progressive dementia often combined with hyperactivity and aggressive behaviour. In order to clone the deficient gene, we purified the enzyme from human placenta and obtained amino acid sequence information. Alignment of one of the CNBr generated internal peptides to sequence from the database revealed the chromosomal location of the gene in the 5' upstream flanking region of the gene for 17-beta-hydroxysteroid-dehydrogenase at 17q21.1. The available DNA sequence was used to clone the cDNA coding for alpha-N- acetylglucosaminidase and analyse its gene structure. The gene is fully contained in the 5' upstream flanking region of the gene for 17-beta- hydroxysteroid-dehydrogenase and interrupted by five introns. The cDNA clone has a length of 2575 bp and encodes a protein of 743 amino acids. Chinese hamster ovary cells transfected with the cDNA construct show alpha-N-acetylglucosaminidase activity about 17-fold over background. This will allow correction studies with NAG deficient Sanfilippo B cell lines and facilitate the development of enzyme replacement therapy for these patients.   相似文献   
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