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51.
A prospective study of 3557 consecutively born neonates from a lower middle class district in Guatemala City documented a 23.8% incidence of intrauterine growth retardation due to fetal malnutrition. Those infants whose weights are below the 10th percentile of a sex- and race-specific birthweight and gestational age distribution, based on a developed country population, were considered to manifest intrauterine growth retardation. Ponderal index values were then used to further classify this population as having chronic fetal malnutrition (above the 10th percentile of the standard distribution) or subacute fetal malnutrition (below the 10th percentile); the incidences of these conditions were 79.1% and 20.8%, respectively. The results of numerous studies carried out in various populations suggest that developing countries have a higher incidence of chronically malnourished infants within the intrauterine growth retardation population, while subacute fetal malnutrition is more prevalent in developed countries. Moreover, it has been shown that chronically malnourished infants do not recover from their intrauterine damage and score the lowest in mental development tests even up to school age. They remain lighter, shorter, and with a smaller head circumference until at least 3 years of age. Based on the incidence rates ascertained in this study, it can be estimated that at least 2 million infants born each year in Latin America are at risk of chronic intrauterine growth retardation. Screening programs are needed to identify at-risk mothers early in pregnancy so that medical and nutritional interventions can be implemented.  相似文献   
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Parallel corticostriatonigral circuits have been proposed that separately process motor, cognitive, and emotional‐motivational information. Functional integration requires that interactions exist between neurons participating in these circuits. This makes it imperative to study the complex anatomical substrate underlying corticostriatonigral circuits. It has previously been proposed that dopaminergic neurons in the ventral mesencephalon may play a role in this circuit interaction. Therefore, we studied in rats convergence of basal ganglia circuits by depositing an anterograde neuroanatomical tracer into the ventral striatum together with a retrograde fluorescent tracer ipsilaterally in the dorsolateral striatum. In the mesencephalon, using confocal microscopy, we looked for possible appositions of anterogradely labeled fibers and retrogradely labeled neurons, “enhancing” the latter via intracellular injection of Lucifer Yellow. Tyrosine hydroxylase (TH) immunofluorescence served to identify dopaminergic neurons. In neurophysiological experiments, we combined orthodromic stimulation in the medial ventral striatum with recording from ventral mesencephalic neurons characterized by antidromic stimulation from the dorsal striatum. We observed terminal fields of anterogradely labeled fibers that overlap populations of retrogradely labeled nigrostriatal cell bodies in the substantia nigra pars compacta and lateral ventral tegmental area (VTA), with numerous close appositions between boutons of anterogradely labeled fibers and nigrostriatal, TH‐immunopositive neurons. Neurophysiological stimulation in the medial ventral striatum caused inhibition of dopaminergic nigrostriatal neurons projecting to the ventrolateral striatal territory. Responding nigrostriatal neurons were located in the medial substantia nigra and adjacent VTA. Our results strongly suggest a functional link between ventromedial, emotional‐motivational striatum, and the sensorimotor dorsal striatum via dopaminergic nigrostriatal neurons.  相似文献   
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BackgroundSelf-sampling for high-risk human papillomavirus (hrHPV) testing is accepted by up to 30% of non-attendees to the regular cervical screening programme. Here, the yield of cervical intraepithelial neoplasia (CIN)2 or worse (⩾CIN2) and CIN3 or worse (⩾CIN3) of 15, 274 HPV self-sampling responders amongst non-attendees were compared to that of 176, 027 women participating in regular screening in the same period and in the same region. We also analysed which subpopulations amongst non-attendees are targeted by HPV self-sampling, and which characteristics relate to hrHPV prevalence and yield of ⩾CIN2/⩾CIN3.MethodData from two consecutive self-sampling studies were pooled. ⩾CIN2/⩾CIN3 yields, screening history, age and ethnic status were retrieved from centralised pathology and screening databases, respectively. A logistic regression model was fitted to analyse method of invitation, ethnicity, age group, and screening history as predictors for response rate, hrHPV presence and ⩾CIN2/⩾CIN3 in non-attendees. For screening history analyses, women <34 years were excluded since it was the first screening round in their life.Findings⩾CIN2/⩾CIN3 yields of HPV self-sampling responders were higher than those of screening participants (⩾CIN2: relative risk (RR) = 1.6, 95% confidence interval = 1.4–1.9; ⩾CIN3: RR = 1.8, 95% CI = 1.5–2.1 with relative risk values increasing with age (test of homogeneity: ⩾CIN2: p = 0.04; ⩾CIN3: p = 0.03).Native Dutch non-attendees responded better than immigrants (32% versus 22%, p < 0·001) and those screened in the previous round revealed a higher response than underscreened (i.e. previous smear taken >7 years ago) or never screened (34% versus 25%, p < 0·001) women. Strikingly, amongst under- and never screened women aged ⩾39 years, never screened women responded better (25% versus 23%, p < 0·001). ⩾CIN2 rates were higher amongst responding native Dutch women than immigrants (p < 0·01), and higher in under-/never screened women than in women screened in the previous round (p < 0·01).InterpretationOffering hrHPV self-sampling increases the efficacy of the screening programme by targeting a substantial portion of non-attendees of all ethnic groups who have not regularly been screened and are at highest risk of ⩾CIN2.  相似文献   
55.
We evaluated the effect of offering brush-based vaginal self-sampling for high-risk human papillomavirus (hrHPV) testing to non-attendees of the cervical screening program on response rate, compliance to follow-up and cervical intraepithelial neoplasia grade 2 or 3 (CIN2+/CIN3+) yield. In addition, concordance of hrHPV test results between physician-taken cervical scrapes and vaginal self-samples was determined. A total of 26,409 nonattending women were randomly assigned to receive a vaginal brush device for hrHPV testing by Hybrid Capture-2 method (i.e., self-sampling group, n = 26,145) or a reinvitation for regular cytology-based screening (i.e., recall control group, n = 264). hrHPV-positive self-sampling responders were invited for a physician-taken scrape for cytology and blinded hrHPV testing. If cytology was abnormal, women were referred for colposcopy. Response rate in the self-sampling group was significantly increased compared to the recall control group (30.8% versus 6.5%; p < 0.001). The concordance rate between hrHPV detection in self-samples and corresponding physician-taken cervical scrape samples was 68.8%. Amongst women with CIN3+ and CIN2+, the concordance rates in hrHPV positivity between both samples were 95.5% and 93.8%, respectively. Adherence at baseline to cytology triage of hrHPV-positive self-sampling women (89.1%) and colposcopy referral of those with abnormal cytology (95.8%) was high. The CIN2+/CIN3+/carcinoma yields were 1.5%, 1.0% and 0.1%, respectively, in self-sampling responders. In conclusion, offering hrHPV testing on self-sampled vaginal material with a brush device to non-attendees significantly increases the attendance to the regular screening program, yields hrHPV test results that are in very good concordance with those of physician-taken scrapes in women with CIN2+/CIN3+, and is effective in detecting CIN2+/CIN3+.  相似文献   
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57.
Studies on relationships between angiogenesis and tumour cell proliferation have provided conflicting results. This study has therefore investigated the relationships between the number and location of fully automatically identified CD31-positive microvessels and interactively segmented mitoses and necrotic compartments by image processing. These features were studied in ten invasive breast cancers, in the 'hot spots' and in whole tumour sections. Microvessel and mitosis hot spots were topographically close or overlapping and were always located at the periphery of the tumour. The numbers of mitoses and microvessels per mm(2) in the hot spot were strongly correlated with the respective numbers in the whole tumour section, as well as mutually. The ratio of mitoses in the hot spot to the whole tumour section was significantly higher than the corresponding microvessel ratio. Mitoses were preferentially located at a distance of 50-150 microm from microvessels. No significant difference was found between the average distance between mitoses and microvessels in the whole tumour sections and in the hot spot (79 vs. 72 microm), although considerable inter-tumour differences were found (hot spot 43-101 microm, tumour 47-111 microm). The presence of necrotic areas correlated with the number of mitoses per mm(2) and necrosis was in general observed at a distance of more than 150 microm from the microvessels, suggesting that necrotic areas have outgrown their vascular system. These results indicate the usefulness of image processing of whole tumour sections for the identification of proliferation and vascularization hot spots, which are strong prognostic factors in breast cancer. The results also support a close relationship between tumour necrosis and microvessels.  相似文献   
58.
We present Path Integral Monte Carlo C code for calculation of quantum mechanical transition amplitudes for 1D models. The SPEEDUP C code is based on the use of higher-order short-time effective actions and implemented to the maximal order $p$=18 in the time of propagation (Monte Carlo time step), which substantially improves the convergence of discretized amplitudes to their exact continuum values. Symbolic derivation of higher-order effective actions is implemented in SPEEDUP Mathematica codes, using the recursive Schrödinger equation approach. In addition to the general 1D quantum theory, developed Mathematica codes are capable of calculating effective actions for specific models, for general 2D and 3D potentials, as well as for a general many-body theory in arbitrary number of spatial dimensions.  相似文献   
59.
An otherwise healthy 1 1/2-year-old boy slowly developed a marked enlargement of his right breast during several months. The lesion was soft, round, fluctuant and translucent. Aspiration revealed the presence of a milk-like fluid. Surgical extirpation was performed. Histologically the cyst showed areas of actively secreting acinar mammary cells.  相似文献   
60.
This paper presents a software system that visualizes the impact of the master surgery schedule on the demand for various resources throughout the rest of the hospital. The master surgery schedule can be seen as the engine that drives the hospital. Therefore, it is very important for decision makers to have a clear image on how the demand for resources is linked to the surgery schedule. The software presented in this paper enables schedulers to instantaneously view the impact of, e.g., an exchange of two block assignments in the master surgery schedule on the expected resource consumption pattern. A case study entailing a large Belgian surgery unit illustrates how the software can be used to assist in building better surgery schedules.  相似文献   
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