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91.
92.
The purpose of the present study was to identify a subset of high-risk patients among surgically treated node-positive patients with stage IB and IIA cervical carcinoma. From 1982 through 1991, 334 patients underwent radical hysterectomy for FIGO stage IB and IIA cervical carcinoma. In 68 patients pathological analysis of the surgical specimen revealed positive pelvic nodes. In this group, a Cox proportional hazard analysis was performed to examine the prognostic significance of clinicopathological variables. Only for adenocarcinoma (P= 0.002) and parametrium infiltration (P= 0.003) was evidence of an association with prognosis found. Based on these two factors, patients with positive pelvic nodes were categorized into a low-risk group (squamous cell carcinoma without parametrium infiltration,N= 33) and a high-risk group (squamous cell carcinoma with parametrium infiltration or adenocarcinoma,N= 34). The 5-year disease-specific survival in the low-risk group was 94% compared with 60% in the high-risk group (P= 0.003). For patients in the high-risk group, there is an urgent need for alternative adjuvant treatment to improve outcome.  相似文献   
93.
To understand the relationship between CD44 gene expressionand an established variable associated with aggressive behaviourin human breast cancer, we have studied apanel of 6 breast cell lines and 40breast tumors selected primarily on the basis ofestrogen receptor (ER) status. CD44s (standard form) mRNAwas assessed by semi-quantitative RT-PCR, and CD44 variantsincorporating exon v7 or v10 were studied byRT-PCR and Southern blot. While CD44 expression wasnot influenced by estrogen in ER+ve MCF-7 cells,CD44s expression was slightly higher (up to 2fold) in ER–ve cells but there was amarked decrease in the range of CD44 variantsincorporating exons v7 or v10. In microdissected tumors,the levels of CD44s showed no correlation withER status but the pattern of expression oflarger forms of CD44 incorporating variant exons v7and v10 was significantly different (p=0.005and p=0.015, respectively) between ER+ve andER–ve tumors, reflecting the pattern seen in thecell lines. These findings suggest that the profileof CD44 expression in breast cancer may reflectcellular differentiation as indicated by the ER phenotype.The influence of these differences in CD44 expressionon the increased metastatic potential of ER negativebreast cancer remains to be determined.  相似文献   
94.
Objective To evaluate gestation-specific risks of stillbirth, neonatal and post-neonatal mortality.
Design Retrospective analysis of 171,527 notified births (1989–1991) and subsequent infant survival at one year, from community child health records.
Setting Notifications from maternity units in the North East Thames Region, London.
Main outcome measures The incidence of births, stillbirths, neonatal and post-neonatal deaths at each gestation after 28 completed weeks. Mortality rates per 1000 total or live births and per 1000 ongoing pregnancies at each gestation were calculated.
Results The rates of stillbirth at term (2.3 per 1000 total births) and post-term (1.9 per 1000 total births) were similar. When calculated per 1000 ongoing pregnancies, the rate of stillbirth increased six-fold from 0.35 per 1000 ongoing pregnancies at 37 weeks to 2.12 per 1000 ongoing pregnancies at 43 weeks of gestation. Neonatal and post-neonatal mortality rates fell significantly with advancing gestation, from 15 1.4 and 31.7 per 1000 live births at 28 weeks, to reach a nadir at 41 weeks of gestation (0.7 and 1.3 per 1000 live births, respectively), increasing thereafter in prolonged gestation to 1.6 and 2.1 per 1000 live births at 43 weeks of gestation. When calculated per 1000 ongoing pregnancies, the overall risk of pregnancy loss (stillbirth + infant mortality) increased eight-fold from 0.7 per 1000 ongoing pregnancies at 37 weeks to 5.8 per 1000 ongoing pregnancies at 43 weeks of gestation.
Conclusion The risks of prolonged gestation on pregnancy are better reflected by calculating fetal and infant losses per 1000 ongoing pregnancies. There is a significant increase in the risk of stillbirth, neonatal and post-neonatal mortality in prolonged pregnancy. This study provides accurate data on gestation-specific risks of pregnancy loss, enabling pregnant women and their carers to judge the appropriateness of obstetric intervention.  相似文献   
95.
Objective To assess the impact of pregnancy upon continence and constipation.
Design A questionnaire survey.
Setting Maternity wards in the Rotunda Lying In Hospital, Dublin, Republic of Ireland.
Population 7771 women who were delivered of liveborn infants.
Methods Questionnaires were delivered and collected by physiotherapy staff as part of routine postnatal care.
Results Analysis of data using χ2 tests showed significant differences between three parity groups [primigravidae, multigravidae (2–4) and multigravidae (5+)] for symptoms of both urinary incontinence (  χ2= 119.54  , df = 2, P = 0.000) and constipation (  χ2= 12.53  , df = 3, P = 0.002); the incidence of both constipation and urinary incontinence increased with parity.
Conclusion The results of this survey have emphasised the relation between parity and postpartum incontinence which stresses the importance of early diagnosis and intervention.  相似文献   
96.
97.
This paper introduces a novel survey instrument to identify distinct components of nutrition knowledge and test for links between knowledge and dietary choices in Southern Malawi. Our first aim is to distinguish respondents' familiarity with recommended behaviours, such as when to start breastfeeding or introduce solid foods, from respondents' factual knowledge about mechanisms, such as whether biscuits or papaya and orange fruit or orange Fanta contribute more to future health. We find knowledge of nutrition behaviours to be strongly associated with more schooling, older age, and being female, whereas knowledge of mechanisms is associated only with training and employment as a health professional. We then test whether this expanded definition of nutrition knowledge is associated with dietary intake when controlling for other factors and find no significant links in these data. Results point to the need for knowledge surveys and public health behaviour‐change campaigns to address the kinds of information that might have the most influence on actual behaviour, potentially including the mechanisms involved in food composition, food safety, and disease transmission.  相似文献   
98.
SARS-CoV-2 is a global challenge due to its ability to mutate into variants that spread more rapidly than the wild-type virus. Because the molecular biology of this virus has been studied in such great detail, it represents an archetypal paradigm for research into new antiviral drug therapies. The rapid evolution of SARS-CoV-2 in the human population is driven, in part, by mutations in the receptor-binding domain (RBD) of the spike (S-) protein, some of which enable tighter binding to angiotensin-converting enzyme (ACE2). More stable RBD-ACE2 association is coupled with accelerated hydrolysis of furin and 3CLpro cleavage sites that augment infection. Non-RBD and non-interfacial mutations assist the S-protein in adopting thermodynamically favorable conformations for stronger binding. The driving forces of key mutations for Alpha, Beta, Gamma, Delta, Kappa, Lambda and Omicron variants, which stabilize the RBD-ACE2 complex, are investigated by free-energy computational approaches, as well as equilibrium and steered molecular dynamic simulations. Considered also are the structural hydropathy traits of the residues in the interface between SARS-CoV-2 RBD and ACE2 protein. Salt bridges and π-π interactions are critical forces that create stronger complexes between the RBD and ACE2. The trend of mutations is the replacement of non-polar hydrophobic interactions with polar hydrophilic interactions, which enhance binding of RBD with ACE2. However, this is not always the case, as conformational landscapes also contribute to a stronger binding. Arginine, the most polar and hydrophilic among the natural amino acids, is the most aggressive mutant amino acid for stronger binding. Arginine blockers, such as traditional sartans that bear anionic tetrazoles and carboxylates, may be ideal candidate drugs for retarding viral infection by weakening S-protein RBD binding to ACE2 and discouraging hydrolysis of cleavage sites. Based on our computational results it is suggested that a new generation of “supersartans”, called “bisartans”, bearing two anionic biphenyl-tetrazole pharmacophores, are superior to carboxylates in terms of their interactions with viral targets, suggesting their potential as drugs in the treatment of COVID-19. In Brief: This in silico study reviews our understanding of molecular driving forces that trigger mutations in the SARS-CoV-2 virus. It also reports further studies on a new class of “supersartans” referred to herein as “bisartans”, bearing two anionic biphenyltetrazole moieties that show potential in models for blocking critical amino acids of mutants, such as arginine, in the Delta variant. Bisartans may also act at other targets essential for viral infection and replication (i.e., ACE2, furin cleavage site and 3CLpro), rendering them potential new drugs for additional experimentation and translation to human clinical trials.  相似文献   
99.
We have characterized the hepatitis B virus state in liver and serum of 38 HBsAg-positive chronic hepatitis patients (chronic active hepatitis (CAH), 19; chronic persistent hepatitis (CPH), 7; cirrhosis, 11; 'normal' carrier, 1) and 21 HBsAg-negative patients. Episomal HBV-DNA in liver, without detectable integrated HBV-DNA sequences, concomitant with HBV-DNA in serum was found in 19 HBeAg-positive patients (CAH, 16; CPH, 1; cirrhosis, 2). Integrated sequences were detected in 13 HBsAg-positive HBeAg-negative patients (CAH, 1; CPH, 5; cirrhosis, 7) and in 1 HBsAg-negative patient. Episomal HBV-DNA and integrated HBV-DNA sequences were observed simultaneously in 1 HBsAg-positive HBeAg-negative CPH patient and in 4 HBsAg-positive cirrhosis patients (2 HBeAg-positive, 2 HBeAg-negative). The presence of HBcAg immunofluorescence corresponded well with that of episomal HBV-DNA. Antiviral therapy is advised for HBsAg-positive chronic hepatitis patients with episomal HBV-DNA, irrespective of the presence of integrated sequences. Since the presence of episomal HBV-DNA in liver is not always accompanied by the presence of serum HBV-DNA, procedures for the selection and evaluation of patients for antiviral therapy should be extended by characterization of the HBV-DNA state in liver biopsies.  相似文献   
100.
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