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61.
Ureaplasma urealyticum in the development of postpartum endometritis   总被引:4,自引:0,他引:4  
OBJECTIVE: Investigation of the clinical significance of Ureaplasma urealyticum and its biovars in the development of postpartum endometritis. STUDY DESIGN: Cervical swabs were cultured for U. urealyticum in women presenting endometritis. The positive U. urealyticum cultures (>10(5) cfu/ml) (study group) were compared with those from women without endometritis (control group). Anti-Ureaplasma antibodies were measured and U. urealyticum biovars were determined by polymerase chain reaction. RESULTS: There was no difference between the prevalence of U. urealyticum in the cervical swabs of both groups, however, the number of cfu per culture, showed a significant difference between study and control groups. Out of the culture positive endometritis patients 39% (26/67) had >10(5) cfu/ml compared to 17% of control patients (5/30) P=0.03. No significant disparity between both the groups was found in the prevalence of the parvo biovar (77% versus 71.5%, respectively). The difference in anti-Ureaplasma antibodies reached no statistical significance (30% versus 18% in study and control groups, respectively). CONCLUSIONS: The significant difference in U. urealyticum culture cfu between both groups suggests that U. urealyticum may play a role in the etiology of this infection. This involvement is dependent not only on the presence or absence of U. urealyticum in the culture, but on its colonization rate in the cervix (>10(5) cfu/ml).  相似文献   
62.
In mammalian cells, neoplastic transformation is directly associated with the expression of oncogenes, loss or simple inactivation of the function of tumour suppressor genes and the production of certain growth factors. Genes for suppression of the development of the neoplastic cellular immunophenotype, as well as inhibitory growth factors, have regulatory functions within the normal processes of cell division and differentiation. Telomerase (a ribonucleoprotein polymerase) activation is frequently detected in various neoplasms. Telomerase activation is regarded as essential for cell immortalisation and its inhibition may result in spontaneous regression of neoplasms. This phenomenon of neoplasms occurs when the malignant tissue mass partially or completely disappears without any treatment or as a result of a therapy considered inadequate to influence systemic neoplastic growth. This definition makes it clear that the term 'spontaneous regression' applies to neoplasms in which the overall malignant disease is not necessarily cured and to cases where the regression may not be complete or permanent. A number of possible mechanisms of spontaneous regression are reviewed, with the understanding that no single mechanism can completely account for this phenomenon. The application of the newest immunological, molecular biological and genetic insights for more individualised and adequate antineoplastic immunotherapy (alternative biotherapy) is also discussed.  相似文献   
63.
We conducted a serosurvey of landscapers to determine if they were at increased risk for exposure to Francisella tularensis and to determine risk factors for infection. In Martha's Vineyard, Massachusetts, landscapers (n=132) were tested for anti-F. tularensis antibody and completed a questionnaire. For comparison, serum samples from three groups of nonlandscaper Martha's Vineyard residents (n=103, 99, and 108) were tested. Twelve landscapers (9.1%) were seropositive, compared with one person total from the comparison groups (prevalence ratio 9.0; 95% confidence interval 1.2 to 68.1; p=0.02). Of landscapers who used a power blower, 15% were seropositive, compared to 2% who did not use a power blower (prevalence ratio 9.2; 95% confidence interval 1.2 to 69.0; p=0.02). Seropositive landscapers worked more hours per week mowing and weed-whacking and mowed more lawns per week than their seronegative counterparts. Health-care workers in tularemia-endemic areas should consider tularemia as a diagnosis for landscapers with a febrile illness.  相似文献   
64.
Aromatic fatty acids such as phenylbutyrate (PB) and its metabolite phenylacetate (PA) induce growth arrest, differentiation and apoptosis in solid tumor cells. Despite their antiproliferative action they were reported to exhibit a synergistic effect in combination with cytotoxic drugs like topotecan, and others. Since the activity of the camptothecines (CPTs) depends on local pH conditions, we investigated, whether PB/PA modulate CPT effects indirectly by affecting intracellular pH in SW620 and SW480 colon cancer cells. The results for the colon carcinoma cells show an antagonistic interaction for the combination of CPT and 0.25-5 mM PA in viability assays, resulting in an approximately 3-fold increase in IC50 (control: 20+/-7 nM). A synergistic effect with significantly increased numbers of late apoptotic/necrotic cancer cells (difference +21+/-4%) and 1.4-fold sensitization were detected upon inclusion of 2.5 mM PA during a 4-h CPT (10 micro;M) loading phase. In response to 0.25-1 mM PA/PB the cells exhibit a reversible decrease of pHi (0.1-0.31 pH units) in HEPES- or bicarbonate-buffered media. Dose-dependent acidification and pHi-recovery occurred following addition of PA and PB after an acid load and inhibition of the Na+/H+-antiporter and bicarbonate exchangers, pointing to a possible intracellular mechanism of cytoplasmic acidification. It is concluded that the synergistic modulation of CPT toxicity by short-term PA/PB treatment in colon carcinoma cells is caused by changes in intracellular pH, possibly affecting quantity and localization of the active closed lactone form of this drug.  相似文献   
65.
Inhalation of foreign body into the tracheobronchial tree is a medical emergency sometimes resulting into sudden death. The current mortality rate due to foreign body inhalation ranges from 0% to 1.8%. Children with or without positive history of aspiration were examined and diagnosis was made on the basis of history, clinical findings, radiological evaluation and strong index of suspicion. A review of 30 cases of suspected foreign body aspiration revealed, children between 6 months were found to be very vulnerable to aspiration. Majority of children were boys. 80% of the patients had positive history of inhalation. Only 50% of the patients presented immediately i.e. within 24 hours after aspiration. Common symptoms were cough and respiratory distress. Decreased air entry was the significant clinical sign (50%). Obstructive emphysema and mediastinal shift were found in the majority of cases (50%). Rigid bronchoscopy under general anaesthesia and patient ventilating using a jet ventilator is a very safe and effective technique.  相似文献   
66.
Monoclonal anti-mouse sperm antibodies have been produced by fusing mouse myeloma cells with spleen cells from rats immunized with epididymal sperm of C3H mice. Immunoprecipitation and immunoperoxidase techniques showed that one such monoclonal antibody, AMS IV-33, recognized a 200 000 dalton protein localized on the acrosomal cap of the sperm cell. Two other monoclonal antibodies AMS IV-54 and -76, reacted with a 68 000 dalton component on the surface of the sperm tail. Both antigenic targets were species specific and were present in about equal amounts on sperm from several different strains of mice. The tail protein was sperm specific, whereas the antibody reacting with the acrosomal cap protein also appeared to react somewhat with antigens present in other mouse tissues.  相似文献   
67.
BACKGROUND: We investigated fetal and total DNA levels in maternal plasma in patients bearing fetuses affected with Down syndrome in comparison to controls carrying fetuses with normal karyotype. METHODS: DNA levels in maternal plasma were measured using real-time quantitative PCR using SRY and beta-globin genes as markers. Twenty-one pregnant women with a singleton fetus at a gestational age ranging from 15 to 19 weeks recruited before amniocentesis (carried out for reasons including material serum screening and advanced material age), and 16 pregnant women bearing fetuses affected with Down syndrome between 17 to 22 weeks of gestation were involved in the study. RESULTS: The specificity of the system reaches 100% (no Y signal was detected in 14 women pregnant with female fetuses) and the sensitivity 91.7% (SRY amplification in 22 of 24 examined samples). The median fetal DNA levels in women carrying Down syndrome (n=11) and the controls (n=13) were 23.3 (range 0-58.5) genome-equivalents/ml and 24.5 (range 0-47.5) genome-equivalents/ml of maternal plasma, respectively (P = 0.62). The total median DNA levels in pregnancies with Down syndrome and the controls were 10165 (range 615-65000) genome-equivalents/ml and 7330 (range 1300-36750) genome-equivalents/ml, respectively (P = 0.32). The fetal DNA proportion in maternal plasma was 0%-6 % (mean 0.8%) in women carrying Down syndrome and 0%-2.6 % (mean 0.7 %) in the controls, respectively (P=0.86). CONCLUSIONS: Our study revealed no difference in fetal DNA levels and fetal DNA: maternal DNA ratio between the patients carrying Down syndrome fetuses and the controls.  相似文献   
68.
Extracts of Aloe vera whole plant, Eucalyptus globulus leaves, Ficus infectoria bark, Ficus religiosa bark and Piper betel leaves were studied for antibacterial activity on resistant and sensitive strains, isolated from skin and soft tissue infections. A combination of hot alcoholic extracts of Ficus infectoria, Ficus religiosa and Piper betel were found to be more effective against all the isolates. The combined extract was formulated in different ointment bases such as polyethylene glycol, gelatin, sodium alginate, carbopol, cream base and honey. These were then evaluated to find a suitable base for preparation of an ointment. In vitro study of the release of antimicrobials and kill-time studies of the herbal ointments was carried out against multi-drug resistant isolate of Pseudomonas. The ointment showed bactericidal activity within 2 h against the resistant strain of Pseudomonas spp.  相似文献   
69.
70.
The World Health Organization (WHO) Labour Care Guide (LCG) is a paper-based labour monitoring tool designed to facilitate the implementation of WHO’s latest guidelines for effective, respectful care during labour and childbirth. Implementing the LCG into routine intrapartum care requires a strategy that improves healthcare provider practices during labour and childbirth. Such a strategy might optimize the use of Caesarean section (CS), along with potential benefits on the use of other obstetric interventions, maternal and perinatal health outcomes, and women’s experience of care. However, the effects of a strategy to implement the LCG have not been evaluated in a randomised trial. This study aims to: (1) develop and optimise a strategy for implementing the LCG (formative phase); and (2) To evaluate the implementation of the LCG strategy compared with usual care (trial phase). In the formative phase, we will co-design the LCG strategy with key stakeholders informed by facility assessments and provider surveys, which will be field tested in one hospital. The LCG strategy includes a LCG training program, ongoing supportive supervision from senior clinical staff, and audit and feedback using the Robson Classification. We will then conduct a stepped-wedge, cluster-randomized pilot trial in four public hospitals in India, to evaluate the effect of the LCG strategy intervention compared to usual care (simplified WHO partograph). The primary outcome is the CS rate in nulliparous women with singleton, term, cephalic pregnancies in spontaneous labour (Robson Group 1). Secondary outcomes include clinical and process of care outcomes, as well as women’s experience of care outcomes. We will also conduct a process evaluation during the trial, using standardized facility assessments, in-depth interviews and surveys with providers, audits of completed LCGs, labour ward observations and document reviews. An economic evaluation will consider implementation costs and cost-effectiveness. Findings of this trial will guide clinicians, administrators and policymakers on how to effectively implement the LCG, and what (if any) effects the LCG strategy has on process of care, health and experience outcomes. The trial findings will inform the rollout of LCG internationally. Trial registration: CTRI/2021/01/030695 (Protocol version 1.4, 25 April 2022). The new WHO Labour Care Guide (LCG) is an innovative partograph that emphasises women-centred, evidence-based care during labour and childbirth. Together with clinicians working at four hospitals in India, we will develop and test a strategy to implement the LCG into routine care in labour wards of these hospitals. We will use a randomised trial design where this LCG strategy is introduced sequentially in each of the four hospitals, in a random order. We will collect data on all women giving birth and their newborns during this period and analyse whether the LCG strategy has any effects on the use of Caesarean section, women’s and newborn’s health outcomes, and women’s experiences during labour and childbirth. While the trial is being conducted, we will also collect qualitative and quantitative data from doctors, nurses and midwives working in these hospitals, to understand their perspectives and experiences of using the LCG in their day-to-day work. In addition, we will collect economic data to understand how much the LCG strategy costs, and how much money it might save if it is effective. Through this study, our international collaboration will generate critical evidence and innovative tools to support implementation of the LCG in other countries.  相似文献   
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