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排序方式: 共有5314条查询结果,搜索用时 15 毫秒
11.
The growth in length and weight of 91 poor urban Bangladeshi infants was monitored at monthly intervals from birth to 1 year. At birth 18%, 22% and 8% were below -2.00 standard deviations of the National Center for Health Statistics (NCHS) height-for-age, weight-for-age and weight-for-height, respectively and at 1 year the percentages were 40%, 40% and 7%. Infant weights over the first 6 months associated positively with both mother's BMI and percentage body fat. Higher mean infant weights from 6 to 12 months were associated with both higher educational status of the mother and monthly family income and the latter two variables provided the best model for predicting weight velocity from birth to 12 months. Internal Z-scores, corrected for day of measurement, provided clear evidence of catch-up/catch-down over the first 6 months with heavier and longer babies at birth showing catch-down while lighter and shorter babies demonstrated catch-up. Infants' weights were almost three times more variable than lengths. Monthly incremental variability of both infant weight and length increased sharply from 6 to 12 months with weight showing significantly more variability. The correlations of birth weight and length with subsequent distances and monthly increment revealed that the first 6 months were dominated by catch-up and catch-down but during the latter half of the year the growth phenomena were influenced mainly by earlier intra-uterine or genetic effects. 相似文献
12.
Groups of wild-caught Culex quinquefaciatus Say, previously tested for the presence of hepatitis B surface antigen (HBsAg), were tested for the presence of hepatitis B e antigen (HBeAg). This antigen was detected at low levels in blood-fed, half-gravid, and gravid groups. A colony of Cx. quinquefasciatus was established in the laboratory and tested for the persistence of HBsAg and HBeAg. Five days after feeding on blood infected with HBsAg and HBeAg, 9 of 20 (45%) pools of Cx. quinquefasciatus were HBeAg-positive and 5 of 20 (25%) pools were HBeAg-positive; low levels of HBsAg and HBeAg were still detectable 28 d after the infective meal in 2 of 20 (10%) and 1 of 20 (5%) pools, respectively. A crude protease extract was prepared from colony mosquitoes, and the effect of this extract on HBsAg and HBeAg present in human serum was tested in vitro. After 20 h, tests for both antigens were still strongly positive. Low levels of HBsAg were detected in ovaries 7 d after infection. Salivary glands were HBsAg- and HBeAg-negative. 相似文献
13.
Tang SN Fakhru'l-Razi A Hassan MA Karim MI 《Artificial cells, blood substitutes, and immobilization biotechnology》1999,27(5-6):411-416
Rubber latex effluent is a polluting source that has a high biochemical oxygen demand (BOD). It is estimated that about 100 million liters of effluent are discharged daily from rubber processing factories. Utilization of this effluent such as the use of a coupled system not only can reduce the cost of treatment but also yield a fermentation feedstock for the production of bioplastic. This study initially was carried out to increase the production of organic acids by anaerobic treatment of rubber latex effluent. It was found that through anaerobic treatment the concentration of organic acids did not increase. Consequently, separation of organic acids from rubber latex effluent by anion exchange resin was examined as a preliminary study of recovering acetic and propionic acids. However, the suspended solids (SS) content in the raw effluent was rather high which partially blocked the ion-exchange columns. Lime was used to remove the SS in the rubber latex effluent. After the lime precipitation process, organic acids were found to adsorb strongly onto the anion exchange resin. Less adsorption of organic acids onto the resin was observed before the lime precipitation. This was probably due to more sites being occupied by colloidal particles on the resin thus inhibiting the adsorption of organic acids. The initial concentration of organic acids in the raw effluent was 3.9 g/L. After ion exchange, the concentration of the organic acids increased to 27 g/L, which could be utilized for production of polyhydroxyalkanoates (PHA). For PHA accumulation stage, concentrated rubber latex effluent obtained from ion exchange resins and synthetic acetic acid were used as the carbon source. Quantitative analyses from fed batch culture via HPLC showed that the accumulation of PHA in Alcaligenes eutrophus was maximum with a concentration of 1.182 g/L when cultivated on synthetic acetic acid, corresponding to a yield of 87% based on its cell dry weight. The dry cell weight increased from 0.71 to 1.67 g/L. On the other hand, using concentrated rubber latex effluent containing acetic and propionic acids resulted in reduced PHA content by dry weight (14%) but the dry cell weight increased from 0.49 to 1.30 g/L. The results clearly indicated that the cells grow well in rubber latex effluent but no PHA was accumulated. This could be due to the high concentration of propionic acid in culture broth or other factors such as heavy metals. Thus further work is required before rubber latex effluent can be utilized as a substrate for PHA production industrially. 相似文献
14.
Mourot L Hintzy F Messonier L Zameziati K Belli A 《European journal of applied physiology》2004,93(3):325-332
This study proposed a non-invasive method to determine the gross (GE, no baseline correction), net (NE, resting metabolism as the baseline correction) and work (WE, unloaded cycling as the baseline correction) efficiencies during cycling at an intensity higher than the maximal aerobic power (MAP). Twelve male subjects performed two exercises consisting of 4 min at 50% MAP followed either by 8 min at 63% MAP or by 8 sequences of 60 s divided into 10 s at 130% MAP and 50 s at 50% MAP (i.e., 63% MAP on average). Oxygen uptake was continuously measured to calculate GE, NE and WE at 50%, 63% and 130% MAP, and the data presented as the means and standard deviations. The GE values were 18.2%, 19.1%, 22.7%, the NE values were 22.4%, 22.8%, 24.3% and the WE values were 34.2%, 31.4% and 27.2% at 50%, 63% and 130% MAP, respectively. The GE and NE increased (P<0.001) whereas the WE decreased (P<0.001) with each increment in power output. The GE was lower than the NE (P<0.001) at 50% and 63% MAP and than the WE (P<0.001) at all intensities. The NE was lower (P<0.001) than the WE at 50% and 63% MAP. These results showed that (1) efficiency index values obtained during supra-maximal exercise were consistent with previous proposals and (2) the efficiency-power output relationships were not limited to sub-maximal intensity levels but were confirmed at higher power output. 相似文献
15.
Demedts IK Brusselle GG Vermaelen KY Pauwels RA 《American journal of respiratory cell and molecular biology》2005,32(3):177-184
Dendritic cells (DC) are specialized antigen-presenting cells, linking innate and adaptive immune responses, and thus play an important role in immunologically mediated diseases, including pulmonary diseases such as asthma and respiratory viral infections. Although much is known about the characteristics of lung DC in animal models, very few data concerning human lung DC are available. The goal of our study was to identify and characterize dendritic cells in human lung by preparing single-cell suspensions from surgical resection specimens and subsequent labeling with the recently developed blood dendritic cell antigen (BDCA) markers. A straightforward isolation procedure was developed to avoid phenotypical and functional changes induced by extensive purification methods. In this way, human lung DC were directly identified without the need for an additional adherence step for further purification. For the first time, we demonstrate the presence of three previously unidentified DC subsets in human lung digests: myeloid DC type 1 (BDCA1+/HLA-DR+), myeloid DC type 2 (BDCA3+/HLA-DR+), and plasmacytoid DC (BDCA2+/CD123+). The presence of CD1a+ DC in the human lung was confirmed. The identification and characterization of different human pulmonary DC subtypes is of great importance for the future development of DC-based immunotherapies. 相似文献
16.
17.
Villamor E Saathoff E Msamanga G O'Brien ME Manji K Fawzi WW 《Journal of acquired immune deficiency syndromes (1999)》2005,38(5):622-626
OBJECTIVES: To examine whether wasting during pregnancy, as measured by weight loss and low weight gain, is associated with increased mother-to-child transmission (MTCT) of HIV-1. METHODS: This was a cohort study in Dar es Salaam, Tanzania, among 957 HIV-1-infected pregnant women. Weight was measured at the first prenatal visit and every month thereafter until delivery. Weight loss was defined as a weekly rate of weight gain =0 and low weight gain as a weekly rate >0 and =166 g/wk. The incidences of presumptive intrauterine transmission (HIV status at birth) and presumptive intrapartum and early breast-feeding transmission (HIV status at 6 weeks) were examined in relation to baseline anthropometric characteristics and weight change during pregnancy using 2xn tables and multivariable binomial regression. RESULTS: Compared with women who gained >/=167 g/wk, weight loss during pregnancy was related to higher risk of intrauterine MTCT (adjusted relative risk [RR] = 2.32, 95% CI = 1.23-4.36, P = 0.009), HIV positive at birth or fetal death (RR = 2.13, 95% CI = 1.40-3.24, P = 0.0004), and HIV positive at birth or early neonatal death (RR = 1.96, 95% CI = 1.26-3.07, P = 0.003). The rate of weight gain during the 3rd trimester was inversely related to the risk of intrapartum/early breast-feeding transmission (adjusted P value, test for trend = 0.05). CONCLUSIONS: Weight loss during pregnancy increases the risk of early MTCT. Identifying causes of wasting during pregnancy may provide clues for new strategies to prevent MTCT. 相似文献
18.
Drolshagen H. Bhavaraju A. Kalkwarf K. J. Karim S. A. Reif R. Sexton K. W. Jensen H. K. 《Hernia》2021,25(5):1259-1264
Hernia - Inguinal hernia repair is one of the most common surgical operations, yet the optimal treatment strategy remains undefined. Treatment of symptomatic inguinal hernias include both surgical... 相似文献
19.
20.
Iris P. Masucci PharmD Karim A. Calis PharmD MPH David L. Bartlett MD H. Richard Alexander MD McDonald K. Horne III MD 《Annals of surgical oncology》1999,6(5):476-480
Background: Three cases of heparin-induced thrombocytopenia (HIT) were observed in patients undergoing isolated limb perfusion (ILP) with melphalan. This occurrence prompted the discontinuation of prophylactic postoperative heparin in ILP patients and its avoidance in patients undergoing isolated hepatic perfusion (IHP). The need to reassess these decisions led to a review of thrombocytopenia in both patient populations.Methods: Records of all patients treated with ILP or IHP at our institution from July 1992 through November 1996, were reviewed. Nine IHP patients were tested prospectively for heparinrelated antibodies using serum samples obtained perioperatively and during the second postoperative week.Results: Thrombocytopenia (<100,000 platelets/L) developed postoperatively in 30% of 131 ILP patients and in 77% of 56 IHP patients. No cases of HIT were identified other than the three who had been previously diagnosed. The prevalence of HIT in heparinized ILP patients was 2.8% (3/108). All nine IHP patients developed heparin-related antibodies postoperatively.Conclusions: Because the prevalence of HIT following ILP is in the range observed in other clinical settings, postoperative heparin prophylaxis is an option. However, it probably should be limited to the first week, and daily platelet counts should be reviewed for a pattern of thrombocytopenia consistent with HIT. The prevalence of heparin-related antibodies after IHP is so high that prophylactic heparin should be avoided in this setting. 相似文献