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31.
Steven A. Block Lynnda Kiess Patrick Webb Soewarta Kosen Regina Moench-Pfanner Martin W. Bloem C. Peter Timmer 《Economics & Human Biology》2004,2(1):21-44
A survey of households in rural Java is used to assess the nutritional impact of Indonesia's drought and financial crisis of 1997/1998. A time-age-cohort decomposition reveals significant nutritional impacts. However, child weight-for-age (WAZ) remained constant throughout the crisis, despite rapid increases in food prices and the consequent household consumption shock. The evidence is consistent with the hypothesis that within households, mothers buffered children's caloric intake, resulting in increased maternal wasting. However, reductions in the consumption of high-quality foods further resulted in increased prevalence of anemia for both mothers and children. The combined effects were particularly severe for cohorts conceived and weaned during the crisis. 相似文献
33.
Lymphocytes from the organized gut-associated lymphoid tissues (GALT) of adult guinea pigs were examined for surface markers characteristic of T and B lymphocytes and for their capacity to function as effector cells in mitogen-induced cellular cytotoxicity (MICC) and antibody-dependent cellular cytotoxicity (ADCC) reactions. GALT lymphocytes formed rosettes with rabbit erythrocytes, a T-cell marker, and underwent proliferative responses in vitro in the presence of phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM). GALT lymphocytes were cytotoxic in vitro for erythrocyte and DBA mastocytoma targets in the presence of PHA. A population of GALT lymphocytes bound aggregated γ-globulin; however, they functioned poorly in ADCC reactions. Thus, organized GALT in the guinea pig contains lymphocytes capable of functioning in T-cell-dependent MICC reactions but either lacks the effector cell population which mediates ADCC or contains an effector cell which functions poorly in ADCC. 相似文献
34.
The incubation of human peripheral blood lymphocytes (PBL) with the natural killer (NK)-sensitive MOLT-4 cell line results in PBL-target cell conjugate formation by certain lymphocyte subpopulations. Following velocity sedimentation, the PBL depleted of these conjugate-forming subpopulations are markedly diminished in the ability to mediate either antibody-dependent cellular cytotoxicity (ADCC) or NK activity. The immediate testing of highly pure PBL subpopulations isolated from the NK target conjugates does not reveal the expected recovery of augmented ADCC or NK levels. Following in vitro incubation, however, the PBL NK target-binding subpopulations do manifest augmented levels of both NK and ADCC, whereas the depleted PBL continue to display diminished NK and ADCC levels. In addition, the degree of augmented NK and ADCC levels recovered by the NK target-binding PBL subpopulations appears dependent on both the time and the temperature of in vitro incubation. Moreover, the ADCC recovery patterns are identical to those observed for NK activity regardless of the time and temperature of in vitro incubation. These results directly demonstrate that the PBL subpopulations isolated from certain NK target cells are functionally enriched in the ability to mediate from ADCC and NK activity. 相似文献
35.
《Animal : an international journal of animal bioscience》2022,16(10):100639
Hypocalcaemia prevention programmes have been widely studied in experimental settings, but their feasibility has not been assessed under field conditions. The main objective of this study was to evaluate, in the context of small dairy farms in western France, whether and how dairy farmers implement prevention programmes and manage the feeding of dry cows to prevent hypocalcaemia. Seventy-nine commercial Holstein dairy farms in Brittany (France) were enrolled in a qualitative study in 2019. We conducted in-person interviews with the farmers to 1) understand the rationale behind the type and seasonality of prevention programmes they implemented and 2) assess how closely they followed common recommendations when implementing them. Most farmers (80 %) used at least one prevention programme, especially supplying a mineral mix formulated to meet the needs of dry cows in late gestation (53 %), acidifying the diet in late gestation (37 %), and supplying calcium at calving (oral or injectable form, 37 %). The use of programmes depended on whether the diet composition varied throughout the year. Among farmers who provided an acidified diet, 25 % did not supply a specific mineral mix to dry cows to ensure an adequate amount of P, Ca, and Mg, which could decrease the effectiveness of the acidification programme. A lack of reliability in feeding practices, such as not weighing feed or not delivering feed frequently enough, was identified for 61 % of contributing farms. Management practices could result in supplying an unsuitable amount of P, Ca, or Mg immediately before calving; for example, inappropriate batching practices around calving were identified for 22 % (cows) to 32 % (heifers) of farms. In addition, nearly all contributing farmers had no processes in place to monitor the effectiveness of the programmes implemented. Reasons for this overall lack of compliance should be explored. 相似文献
36.
Nikola Cesarovic Paulin Jirkof Andreas Rettich Margarete Arras 《Journal of visualized experiments : JoVE》2011,(57)
The laboratory mouse is the animal species of choice for most biomedical research, in both the academic sphere and the pharmaceutical industry. Mice are a manageable size and relatively easy to house. These factors, together with the availability of a wealth of spontaneous and experimentally induced mutants, make laboratory mice ideally suited to a wide variety of research areas.In cardiovascular, pharmacological and toxicological research, accurate measurement of parameters relating to the circulatory system of laboratory animals is often required. Determination of heart rate, heart rate variability, and duration of PQ and QT intervals are based on electrocardiogram (ECG) recordings. However, obtaining reliable ECG curves as well as physiological data such as core body temperature in mice can be difficult using conventional measurement techniques, which require connecting sensors and lead wires to a restrained, tethered, or even anaesthetized animal. Data obtained in this fashion must be interpreted with caution, as it is well known that restraining and anesthesia can have a major artifactual influence on physiological parameters1, 2.Radiotelemetry enables data to be collected from conscious and untethered animals. Measurements can be conducted even in freely moving animals, and without requiring the investigator to be in the proximity of the animal. Thus, known sources of artifacts are avoided, and accurate and reliable measurements are assured. This methodology also reduces interanimal variability, thus reducing the number of animals used, rendering this technology the most humane method of monitoring physiological parameters in laboratory animals3, 4. Constant advancements in data acquisition technology and implant miniaturization mean that it is now possible to record physiological parameters and locomotor activity continuously and in realtime over longer periods such as hours, days or even weeks3, 5.Here, we describe a surgical technique for implantation of a commercially available telemetry transmitter used for continuous measurements of core body temperature, locomotor activity and biopotential (i.e. onelead ECG), from which heart rate, heart rate variability, and PQ and QT intervals can be established in freeroaming, untethered mice. We also present pre-operative procedures and protocols for post-operative intensive care and pain treatment that improve recovery, well-being and survival rates in implanted mice5, 6. 相似文献
37.
Objective: Previous research has addressed the relationship between BMI and chronic disease in primary care; however, little has been done with regard to the association between obesity and depression in primary care. The purpose of this paper is to assess the relationship between obesity and chronic conditions including depression. Research Methods and Procedures : Data from primary care patients seen at a university‐based family medicine clinic in the southeastern United States were extracted for the time between January 1, 1999 and January 1, 2002. Data extracted included most recent height and weight, age, ethnicity, pregnancy status, number of office visits, blood pressure, cholesterol, hemoglobin A1C, current diagnoses, and medications. Results : A total of 8197 patients were included in the analysis. Sixty‐nine percent of patients seen in a 3‐year period were either overweight or obese. Comparing blood pressure, cholesterol, diagnoses, and medications between BMI groups found differences in virtually all categories. Diagnoses of high cholesterol, hypertension, diabetes, and depression significantly increased for obese patients. Discussion : Obese patients are over‐represented in primary care, and this over‐representation of obesity correlates with several diagnoses, including depression. Depression is a chronic disease that may interfere with health‐related behaviors and must be addressed within the health care system. 相似文献
38.
Unlike any great apes, humans have expanded into a wide variety of habitats during the course of evolution, beginning with the transition by australopithecines from forest to savanna habitation. Novel environments are likely to have imposed hominids a demographic challenge due to such factors as higher predation risk and scarcer food resources. In fact, recent studies have found a paucity of older relative to younger adults in hominid fossil remains, indicating considerably high adult mortality in australopithecines, early Homo, and Neanderthals. It is not clear to date why only human ancestors among all hominoid species could survive in these harsh environments. In this paper, we explore the possibility that hominids had shorter interbirth intervals to enhance fertility than the extant apes. To infer interbirth intervals in fossil hominids, we introduce the notion of the critical interbirth interval, or the threshold length of birth spacing above which a population is expected to go to extinction. We develop a new method to obtain the critical interbirth intervals of hominids based on the observed ratios of older adults to all adults in fossil samples. Our analysis suggests that the critical interbirth intervals of australopithecines, early Homo, and Neanderthals are significantly shorter than the observed interbirth intervals of extant great apes. We also discuss possible factors that may have caused the evolutionary divergence of hominid life history traits from those of great apes. 相似文献
39.
40.
Diane E. Eyer 《Human nature (Hawthorne, N.Y.)》1994,5(1):69-94
A study of the research on postpartum mother-infant bonding shows that results from poorly constructed research programs were
published in major journals and became a part of hospital policy because the bonding concept was politically useful in the
struggle between advocates of natural childbirth and managers of the medical model of birth. The concept was also uncritically
accepted because it was consistent with a longstanding ideology of motherhood that sees women as the prime architects of their
children’s personalities.
Diane Eyer earned her Ph.D. in developmental psychology from the University of Pennsylvania. She is currently writing a book
on the ways in which the concepts of bonding and attachment have affected our understanding of appropriate early childcare. 相似文献