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291.
Carlos Rosas Edwin L. Cooper Cristina Pascual Roberto Brito Rolando Gelabert Teresa Moreno Ariadna Sánchez 《Marine Biology》2007,152(4):929-938
To assess the health status of aquatic ecosystems, specialized tools and strategies are needed to study the changes induced
in oceanic systems by human activity. The Gulf of Mexico has a tremendous ecological importance because of its biological
diversity. The present paper defines baseline levels of blood metabolites and immune components for wild tropical populations
of F. duorarum: an important shrimp species of the Gulf of Mexico. Osmotic pressure (OP), osmotic capability (OC), oxy hemocyanin (OxyHc),
glucose, digestive gland glycogen, proteins, cholesterol, lactate, acylglycerols (AG) were used as indicators of physiological
and nutritional status; phenoloxidase activity, quantification of hemocytes, as well as respiratory burst, were used to assess
the immunological status. There were no differences between sexes in either live weight or physiological and nutritional conditions.
Only total blood protein, oxy hemocyanin, and digestive gland glycogen showed normally distributed data. All the remaining
blood parameters were right- or left-skewed. A median live weight of 9.5 g was registered for the sampled population. Median
values of 955 and −91.85 mOsm/kg (OP and OC, respectively) were obtained, indicating that shrimp were slightly hypo-osmotic
in relation to sea water. A proportion of 27% of OxyHc of the total protein (OxyHc/Prot) was calculated for the F. duorarum population. ProPO and PO showed no normal distribution and were not different between sexes. A right-skewed distribution was
observed. Total hemocytes, hyaline (HC) and granular cells (GC) showed differences between sexes, with higher values in females
than males. A similar proportion of HC (69%) and GC (30%) of total cells were observed between sexes. Basal and activated
respiratory burst showed differences between sexes with higher values for females than for males. The current results provide
indicators of the nutritional and immune status of F. duorarum that can be used to detect changes in trophic relations and health at a population level. 相似文献
292.
This paper presents a first result of an investigation of the presence of anthropogenic pollutants named polychlorinated biphenyls
(PCBs, sum of 25 congeners) in snow samples in the Aconcagua Mountains in the Andean Range, along an altitudinal gradient.
Samples were taken during an expedition in 2003 and analysed by using a specific technique of thermodesorption and GC-MS adapted
to small amount of sample. Mountain ecosystems could be efficient natural trap of persistent organic pollutants (POPs) transported
by the atmosphere, and it is shown in this note that PCBs are also present in snow samples but at low concentrations, levels
ranged from 0.02 to 0.190 ng/L. The detected congeners were those more persistent (PCB 138, PCB180) and compared to other
mountain and cold areas around the world, detected levels are in the low range indicating that pollution levels are lower
in the southern hemisphere. This results points out the need of investigating with some more detail the role of mountains
in the trapping of POPs and the associated risks including the climate change. 相似文献
293.
294.
Salvatore Pipitone Velio Sperandeo Maurizio Mongiovi Grillo Roberto Giuseppe Centineo 《黑龙江环境通报》2002,22(2):131-136
Ventricular aneurysms have rarely been reported prenatally. Their prognosis is variable depending on factors such as early detection, their relative size in comparison to the ventricular cavity, growth on follow-up, and signs of cardiac failure. In view of the fact that it may be useful to report on additional cases in order to make available further information on aetiology, prognosis and neonatal management, we hereby report on two cases of ventricular aneurysm with good mid-term prognosis. One case of apical aneurysm of the left ventricle was associated with a muscular ventricular septal defect, the features of which are compatible with a fetal myocardial infarction and ventricular septal rupture in absence of coronary artery anomalies as demonstrated by catheterisation. Another case of sub-tricuspidal aneurysm of the right ventricle associated with mitral prolapse appears to be a component of diffuse connective dysplasia. Despite the early gestational age at diagnosis, the large size of the aneurysm and the associated defect, both the infants were asymptomatic in infancy prompting a conservative management. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
295.
Corvalán RM Osses M Urrutia CM 《Journal of the Air & Waste Management Association (1995)》2002,52(2):167-174
Depending on the final application, several methodologies for traffic emission estimation have been developed. Emission estimation based on total miles traveled or other average factors is a sufficient approach only for extended areas such as national or worldwide areas. For road emission control and strategies design, microscale analysis based on real-world emission estimations is often required. This involves actual driving behavior and emission factors of the local vehicle fleet under study. This paper reports on a microscale model for hot road emissions and its application to the metropolitan region of the city of Santiago, Chile. The methodology considers the street-by-street hot emission estimation with its temporal and spatial distribution. The input data come from experimental emission factors based on local driving patterns and traffic surveys of traffic flows for different vehicle categories. The methodology developed is able to estimate hourly hot road CO, total unburned hydrocarbons (THCs), particulate matter (PM), and NO(x) emissions for predefined day types and vehicle categories. 相似文献
296.
Based on observations in animals, there is an increasing evidence that a number of persistent organochlorine pollutants can alter the endocrine homeostasis, this resulting in toxic effects in particular in the developing organism. However, the role of these chemicals in determining endocrine-related diseases in humans, and possibly a decrease of fertility, is still controversial. Exposure data concerning the human reproductive system are essential for risk assessment. Based on this, the occurrence in follicular fluid of polychlorobiphenyls (PCBs), 2,3,7,8-chlorosubstituted polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)-ethane (p,p'-DDT) and its metabolites, and hexachlorobenzene (HCB) was investigated. With respect to PCBs, the sum of the three most abundant congeners (PCBs 138, 153 and 180) was 1230 ng/g, lipid basis (0.37 ng/g, wet weight). Congener distribution profile overlapped what is usually observed in other human tissues, as blood and milk. PCDDs, PCDFs, p,p'-DDT and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethane (p,p'-DDD) were below their determination limits. 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) and HCB were detected in concentrations respectively in the order of 700 and 70 ng/g, lipid basis (approximately 0.2 and approximately 0.02 ng/g, wet weight). 相似文献
297.
A flood event was investigated in a measurement section of the estuary of the Dese River, the major tributary of the Venice Lagoon (mean annual discharge=7.5 m3/s), to observe the variations induced by the flow on the physico-chemistry of the water column and the transport of particles and pollutants. The flood was generated by a typical summer storm, which had a return period of 2 years. The study was based on the continuous recording of the discharge and the measurement of both current speed and physico-chemical variables along the vertical profile. Water samples were also collected for the analysis of total and dissolved heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Zn), and nutrients (TKN, N-NO3-, N-NO2-, N-NH3, total phosphorous, P-PO43-). The suspended particle matter (SPM) concentration increased in the water column during the flood, and the discharge versus SPM relationship showed a counterclockwise hysteresis. The occurrence of hysteresis was related to the delayed response of the load, deriving from the runoff on the basin soils with respect to materials mobilized from the streambed in the initial phases of the flood. The transport of most of the analysed heavy metals was driven by the SPM. The increase in concentration of this parameter significantly affected the amount of Fe, Cu, Pb, Cr, Ni, and partially Zn transported by the stream. Among nutrients, N-NO3- concentration also increased significantly during the flood, due to the runoff on agricultural surfaces. The study allowed describing the mechanisms of load generation with high flow magnitudes, highlighting the importance of floods in the transport of materials and pollutants from the drainage basin to the Venice Lagoon. 相似文献
298.
Herbert Valensise Elena Vaquero Caterina De Carolis Elisa Stipa Roberto Perricone Domenico Arduini Carlo Romanini 《黑龙江环境通报》1995,15(6):509-517
Antiphospholid antibodies are associated with fetal distress and fetal death. Although different therapeutic regimens have been used, the incidence of fetal growth retardation varies between 30 and 60 per cent of reported cases. We report the evolution of fetal growth in patients with antiphospholipid antibody syndrome treated with high-dose intravenous immunoglobulins (IVIG). Fourteen patients with a history of recurrent spontaneous abortion and immunological diagnosis of antiphospholipid syndrome were followed longitudinally. Intravenous immunoglobulin at a dose of 0.5 g/kg body weight for two consecutive days was started from the fifth week of pregnancy and repeated every 4 weeks until the 33rd week of gestation. Fetal biometry was evaluated longitudinally from the appearance of the gestational sac at 4 weekly intervals. In the period between 26 and 34 weeks, the frequency of evaluation was increased to every 14 days. Data obtained were compared with a control group of 70 fetuses with uneventful pregnancies matched for gestational age. Neonatal weight is shown in relation to the centiles for the normal population. One patient out of 14 (7.1 per cent) developed gestational hypertension and abruptio placentae. No other pregnancy complications were seen. No proteinuria was found. The mean maternal age was 31.2±3.8 years. Median birth weight was 3433 g±287. The median centile of the birth weight was 65.3±18.6. Mean gestational age at delivery was 1.3 weeks. No fetal or neonatal growth retardation was seen. No significant differences were found in the biometrical parameters investigated in the various gestational ages vs. the control group (Student's t-test not significant); a significant increase in head circumference (P< 0.001) and abdominal circumference (P< 0.05) was found at 36–37 weeks gestational age in the IVIG-treated fetuses. The presence of antiphospholipid antibodies is considered detrimental for pregnancy outcome because of their negative effects on placental vascular perfusion and fetal transfer of metabolites. The use of IVIG seems to avoid or inhibit the reduced availability of nutrients for the fetal anabolic functions, as the expected reduction in fetal growth was not seen in our series. 相似文献
299.
Professor Umberto Nicolini Alessandra Kustermann Beatrice Tassis Roberto Fogliani Andrea Galimberti Elena Percivalle Maria Grazia Revello Giuseppe Gerna 《黑龙江环境通报》1994,14(10):903-906
Fifteen fetuses at risk of congenital human cytomegalovirus (HCMV) infection underwent prenatal diagnosis at 16–30 weeks' gestation by a combination of amniocentesis and fetal blood sampling. HCMV was isolated from the amniotic fluid in six patients, but HCMV-specific IgM was detected in only three of them. Two of the nine neonates, who were delivered following a negative prenatal diagnosis, had congenital HCMV infection diagnosed by virus isolation in the urine. The interval from infection to prenatal testing was 3 and 4 weeks in the two false-negative cases and ⩾ 7 weeks in the true-positive cases. Although timely testing for HCMV infection allows the option of termination of pregnancy, it may be flawed by false-negative results. 相似文献
300.
Jose A. Nores MD Siegfried Rotmensch Roberto Romero Cecilia Avila Mona Inati John C. Hobbins 《黑龙江环境通报》1992,12(9):741-753
Atelosteogenesis type II is a lethal chondrodysplasia characterized by severe micromelia, spinal abnormalities, talipes equinovarus, and abducted thumbs and toes. We present a case diagnosed at 21 weeks of gestation in which antenatal sonographic and post-mortem radiological findings were correlated. The patient had a recurrence of this disorder in a subsequent pregnancy which was terminated at 15 weeks, supporting previous reports of an autosomal recessive inheritance pattern. The feasibility of diagnosing the following morphological features by prenatal ultrasonography is demonstrated: coronal clefts of the vertebral bodies, metaphyseal and epiphyseal abnormalities, spinal deviations such as cervical kyphosis and a horizontal sacrum, additional ossification centres in the pelvis, and preaxial deviation of the thumbs and toes. The differential diagnosis of this disorder from other skeletal dysplasias with similar features is discussed. 相似文献