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1.
Celina Lepecka-Klusek Grzegorz Jakiel 《The European journal of contraception & reproductive health care》2007,12(1):51-57
BACKGROUND: To evaluate the influence assisted reproduction techniques (ARTs) may have on women's adaptation to resulting pregnancies. METHODS: Retrospective assessment of how women adapt to their pregnancies following ART. A questionnaire was used that ranked their attitudes according to the 5-grade Likert scale. The study included 250 women who gave birth to their first child. Of these pregnancies, 125 had been obtained by means of ART; the remaining 125 were naturally conceived. RESULTS: Difficulties in adaptation to pregnancy were significantly more frequent in women whose pregnancies resulted from the use of ARTs than in those who had conceived naturally (p = 0.000005). The subjects in the first group were significantly older (p = 0.04), more affluent (p = 0.000005) and had more frequently interrupted their professional work than women in the latter group. The two groups did not differ with regard to frequency of hospitalisations. CONCLUSIONS: ART significantly increases difficulties in adaptation to resulting pregnancies. The main factors responsible for these difficulties are age, socio-economic conditions and interruption of professional activity. 相似文献
2.
A framework for evaluating image segmentation algorithms. 总被引:4,自引:0,他引:4
Jayaram K Udupa Vicki R Leblanc Ying Zhuge Celina Imielinska Hilary Schmidt Leanne M Currie Bruce E Hirsch James Woodburn 《Computerized medical imaging and graphics》2006,30(2):75-87
The purpose of this paper is to describe a framework for evaluating image segmentation algorithms. Image segmentation consists of object recognition and delineation. For evaluating segmentation methods, three factors-precision (reliability), accuracy (validity), and efficiency (viability)-need to be considered for both recognition and delineation. To assess precision, we need to choose a figure of merit, repeat segmentation considering all sources of variation, and determine variations in figure of merit via statistical analysis. It is impossible usually to establish true segmentation. Hence, to assess accuracy, we need to choose a surrogate of true segmentation and proceed as for precision. In determining accuracy, it may be important to consider different 'landmark' areas of the structure to be segmented depending on the application. To assess efficiency, both the computational and the user time required for algorithm training and for algorithm execution should be measured and analyzed. Precision, accuracy, and efficiency factors have an influence on one another. It is difficult to improve one factor without affecting others. Segmentation methods must be compared based on all three factors, as illustrated in an example wherein two methods are compared in a particular application domain. The weight given to each factor depends on application. 相似文献
3.
Luciana Dias de Oliveira Elsa Regina Justo Giugliani Lílian Córdova do Espírito Santo Maristela Cavalheiro Tamborindeguy Fran?a Enilda Maria Lara Weigert Celina Valderez Feijó Kohler Ana Lúcia de Lourenzi Bonilha 《Journal of human lactation》2006,22(3):315-321
This randomized clinical trial compared frequencies of exclusive breastfeeding and lactation-related problems during the first 30 days among 74 mothers who received a 30-minute counseling session on breastfeeding technique in the maternity ward, and 137 controls. The frequency of exclusive breastfeeding among mothers who had received intervention was similar to controls by 7 days (79.7% vs 82.5%, respectively) and 30 days (60.8% vs 53.3%). There was no difference between groups in the frequency of sore nipples at 7 and 30 days, in breast engorgement and mastitis, and in the quality of breastfeeding technique at 30 days. Therefore, a single intervention at maternity was not sufficient to improve breastfeeding technique, increase exclusive breastfeeding rates, and reduce the incidence of breastfeeding problems during the first month. 相似文献
4.
Angiopoietin-1 causes reversible degradation of the portal microcirculation in mice: implications for treatment of liver disease
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Ward NL Haninec AL Van Slyke P Sled JG Sturk C Henkelman RM Wanless IR Dumont DJ 《The American journal of pathology》2004,165(3):889-899
In many different liver diseases, such as cirrhosis, degradation of the microcirculation, including obliteration of small portal or hepatic veins contributes to disease-associated portal hypertension. The present study demonstrates the importance of angiogenesis in the establishment of arteriovenous shunts and the accompanying changes to the venous bed. One aspect of angiogenesis involves the branching of new vessels from pre-existing ones, and the molecular mechanisms controlling it are complex and involve a coordinated effort between specific endothelial growth factors and their receptors, including the angiopoietins. We modulated the hepatic vasculature in mice by conditionally expressing angiopoietin-1 in hepatocytes. In mice exposed to angiopoietin-1 during development, arterial sprouting, enlarged arteries, marked loss of portal vein radicles, hepatic vein dilation, and suggestion of arteriovenous shunting were observed. Most importantly, these phenotypic changes were completely reversed within 14 days of turning off transgene expression. Expression of excess angiopoietin-1 beginning in adulthood did not fully recapitulate the phenotype, but did result in enlarged vessels. Our findings suggest that controlling excessive angiogenesis during liver disease may promote the restoration of the portal vein circuit and aid in the resolution of disease-associated portal hypertension. 相似文献
5.
Pérez-Costas E Meléndez-Ferro M Pérez-García CG Caruncho HJ Rodicio MC 《Journal of chemical neuroanatomy》2004,27(1):7-21
The expression of reelin, a large extracellular matrix glycoprotein, was studied in the brain of pre-spawning adult sea lampreys by immunohistochemistry using two monoclonal antibodies against this protein. Reelin immunoreactive (reln-ir) neurons were observed in the olfactory bulb, and pallial and subpallial regions in the telencephalon. In the diencephalon, reln-ir cells were observed in some hypothalamic nuclei, in the nucleus of Bellonci, and in the habenula. In the mesencephalon, this protein was detected in several nuclei related with the centrifugal visual system, although the optic tectum was devoid of immunoreactivity. The hindbrain showed several nuclei with immunopositive neurons, including the branchiomeric nerve motor nuclei and also some groups of non-giant cells of the reticular formation. The rostral spinal cord showed some immunopositive neurons mainly located in lateral and ventral positions. Overall, the pattern of distribution of reelin in the adult sea lamprey correlates with the previously reported in other adult vertebrates. Furthermore, the wide distribution of reelin in the adult lamprey brain is consistent with a possible existence of different roles for this protein not related with development in the central nervous system (CNS) of vertebrates (i.e. neuronal plasticity and/or maintenance). 相似文献
6.
Daniel H Berrocal Germán E González Alejandro Fernández Susana Perez Luciana Wilensky Celina Morales Liliana Grinfeld Ricardo J Gelpi 《Cardiovascular pathology》2008,17(5):289-296
BACKGROUND: It is not known whether overexpansion modifies stent recoil, symmetric distribution of struts, and neointimal hyperplasia. OBJECTIVES: The objectives were (a) to evaluate whether stent overexpansion modifies the geometric configuration of the stent in the arterial wall, (b) to determine the relationship between overexpansion and stent recoil, and (c) to evaluate the relationship between the distribution of struts and neointimal hyperplasia. METHODS: Twenty tubular stainless steel 316L stents (3.0 and 3.5 mm in diameter) were implanted at 20 and 10 atm, respectively, in the abdominal aorta of New Zealand rabbits fed a hypercholesterolemic diet (1% cholesterol). Sham operations were also performed in seven animals. Eight weeks after implantation or sham operation, an intravascular ultrasound (IVUS) study was performed to measure stent recoil and aid in stent classification (symmetric or asymmetric) according to strut distribution. The degree of injury and neointimal hyperplasia were also evaluated in hematoxylin-eosin stained sections. RESULTS: The symmetry/asymmetry of stents assessed by IVUS, as well as the neointimal hyperplasia, was similar in both groups. Stent recoil was significantly greater in the 3.0-mm stent (overexpanded) group (0.28+/-0.02 mm), as compared with stent recoil in the 3.5-mm stent group (0.10+/-0.01 mm, P<.05). The neointimal hyperplasia in histological slices, independent of the implant technique, was predominantly in zones with higher strut concentration as compared with zones with fewer struts. CONCLUSIONS: Stent overexpansion enhanced stent recoil and did not modify symmetric and asymmetric strut distribution. Neointimal hyperplasia was not modified by the implant technique. Interestingly, significant hyperplasia was observed in locations with greater strut concentration, independent of overexpansion. 相似文献
7.
Dual role of interleukin-4 (IL-4) in pulmonary paracoccidioidomycosis: endogenous IL-4 can induce protection or exacerbation of disease depending on the host genetic pattern
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Arruda C Valente-Ferreira RC Pina A Kashino SS Fazioli RA Vaz CA Franco MF Keller AC Calich VL 《Infection and immunity》2004,72(7):3932-3940
Resistance to paracoccidioidomycosis, the most important endemic mycosis in Latin America, is thought to be primarily mediated by cellular immunity and the production of gamma interferon. To assess the role of interleukin-4 (IL-4), a Th2 cytokine, pulmonary paracoccidioidomycosis in IL-4-depleted susceptible (B10.A) and intermediate (C57BL/6) mice was studied. Two different protocols were used to neutralize endogenous IL-4 in B10.A mice: 1 mg of anti-IL-4 monoclonal antibody (MAb)/week and 8 mg 1 day before intratracheal infection with 10(6) Paracoccidioides brasiliensis yeast cells. Unexpectedly, both protocols enhanced pulmonary infection but did not alter the levels of pulmonary cytokines and specific antibodies. Since in a previous work it was verified that C57BL/6 mice genetically deficient in IL-4 were more resistant to P. brasiliensis infection, we also investigated the effect of IL-4 depletion in this mouse strain. Treatment with the MAb at 1 mg/week led to less severe pulmonary disease associated with impaired synthesis of Th2 cytokines in the lungs and liver of control C57BL/6 mice. Conversely, in IL-4-depleted C57BL/6 mice, increased levels of tumor necrosis factor alpha and IL-12 were found in the lungs and liver, respectively. In addition, higher levels of immunoglobulin G2a (IgG2a) and lower levels of IgG1 antibodies were produced by IL-4-depleted mice than by control mice. Lung pathologic findings were equivalent in IL-4-depleted and untreated B10.A mice. In IL-4-depleted C57BL/6 mice, however, smaller and well-organized granulomas replaced the more extensive lesions that developed in untreated mice. These results clearly showed that IL-4 can have a protective or a disease-promoting effect in pulmonary paracoccidioidomycosis depending on the genetic background of the host. 相似文献
8.
Agnieszka K Witkiewicz Sooryanarayana Varambally Ronglai Shen Rohit Mehra Michael S Sabel Debashis Ghosh Arul M Chinnaiyan Mark A Rubin Celina G Kleer 《Cancer epidemiology, biomarkers & prevention》2005,14(6):1418-1423
Alpha-methylacyl-CoA racemase (AMACR) is an enzyme involved in the metabolism of fatty acids and is an important tissue biomarker in the prostate to distinguish normal glands from prostate cancer. Here, for the first time, we evaluated the expression of AMACR protein in normal breast, ductal carcinoma in situ, and invasive carcinomas. By immunofluorescence and immunohistochemistry, AMACR was seen in cytoplasmic granules consistent with a mitochondrial and peroxisomal localization. AMACR expression was determined by immunohistochemistry on 160 invasive carcinomas with long follow-up, using a high-density tissue microarray, and evaluated by two methods: standard pathology review and quantitative image analysis. AMACR was overexpressed in 42 of 160 (26%) invasive carcinomas, and it was associated with a decrease in tumor differentiation, a feature of aggressive breast cancer. Quantitative analysis allowed for better discrimination and more accurate evaluation of low-intensity staining. In conclusion, AMACR protein is expressed in normal breast and its expression seems to increase in invasive carcinomas. We observed stronger AMACR protein expression in high-grade carcinomas when compared with low-grade ones. Quantitative image analysis is a novel way to accurately and reproducibly evaluate immunohistochemistry in breast tissue samples using high-density tissue microarrays. 相似文献
9.
A supportive approach to care for women during the second stage of labor that primarily relies on the laboring woman's involuntary expulsive urges has been advocated. We aimed to learn about the clinical circumstances surrounding the caregiver shift from being primarily supportive to directing women regarding their bearing-down efforts. This research analyzed the communications of 10 birth attendants and women during the expulsive phase of labor using videotapes recorded from two studies carried out between 1986 and the present. The occasions when a birth attendant shifted verbalizations were identified, and categories of the rationales that may have influenced the modification in caregiver behavior were developed. Birth attendants most frequently provided directions to help the woman push effectively, that is, to focus the woman's bearing-down efforts during maternal distress, fatigue, fear, and pain to expedite the labor process (38% of the occasions of caregiver change in verbalizations). The next most frequent clinical situations when caregivers offered directions about "pushing" were diminished urge to bear-down with epidural analgesia (10%), routine arbitrary practices (9% caregiver and 6% by supportive companion), and fetal distress (<1%). A category of "supportive direction" (20%) was identified. This care strategy has not been previously reported. It combined direction with support in a way that was supportive rather than overriding the woman's involuntary efforts. 相似文献
10.
Criado PR de Carvalho JF Ayabe LA Brandt HR Romiti R Maruta CW 《Rheumatology international》2012,32(8):2551-2555
Adult-onset Still’s disease (AOSD) patients typically present with arthralgia, fever, lymphadenopathy and a transient salmon maculopapular rash. Only approximately 25 cases of AOSD with urticaria were described in the literature. In this article, the authors report three additional cases of AOSD with urticarial and dermographic lesions who had a good clinical response to glucocorticoid and antihistamines. A review of the literature concerning this issue is also herein written. 相似文献