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41.
In seven of 30 consecutive patients with the adult respiratory distress syndrome, disseminated intravascular coagulation (DIC) developed. Increasing respiratory dysfunction characterized by decreased effective static compliance and increased hypoxemia coincided with the development of DIC. Patients in whom DIC developed were characterized by a high incidence of bleeding, gangrene of the extremities, renal dysfunction, mortality and autopsy evidence of fibrin microthrombi in the lungs, kidney and skin. In 12 of 23 patients who did not meet the criteria for DIC, the platelet count decreased by at least 50 per cent of the initial values at some time during their illness. Fibrin microthrombi were found in the lungs in the majority of the patients subjected to autopsy. These data support the concept that depostion of platelet on damaged pulmonary capillary endothelium may be more common in the adult respiratory distress syndrome than the DIC syndrome.  相似文献   
42.
Members of the immediate families of twenty children with specific reading disability were examined to determine the prevalence of reading disability within the families. A procedure was developed for identifying adults who may have compensated for a disability manifested more clearly in childhood. Forty-five percent of 75 first-degree relatives of the parents were affected and there was a significantly greater number of affected male relatives than females. No single mode of genetic transmission is evident after inspection of the pedigrees. It is suggested that the disorder is genetically heterogeneous and that subgroups of disabled readers should be looked for.  相似文献   
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Hartnup disease is a rare genetic disorder of amino acid transport associated with variable and intermittent clinical abnormalities. A family is described in which three siblings had an intermittently progressive neurological disease and two of the affected siblings had the Hartnup-pattern aminoaciduria. Neuropathological examination of one case showed severe diffuse atrophy, generalized neuronal loss in the cortex, and Purkinje cell loss in the cerebellum. In vivo and in vitro studies of intestinal amino acid transport in the surviving sibling indicated a partial defect in the transport of several neutral amino acids (tryptophan, alanine, serine, and methionine) with normal transport of other neutral amino acids (threonine, phenylalanine, histidine, tyrosine, and isoleucine). Transport of glycine, proline, hydroxyproline, and the basic amino acids appeared normal.  相似文献   
45.
Long strictures of the intrapancreatic portion of the common bile duct were found in 6 patients with chronic pancreatitis. These strictures were responsible for painless obstructive jaundice, recurrent cholangitis, secondary biliary cirrhosis, and chronic abdominal pain difficult to distinguish from that caused by pancreatitis. Endoscopic retrograde cholangiopancreatography and intraoperative cholangiography were invaluable in making the diagnosis and in planning surgical correction. Decompression of the biliary tree by anastomosis of the gallbladder or common duct to the small intestine completely relieved symptoms and allowed liver function to improve significantly. Common duct stricture as a complication of chronic pancreatitis should be considered in the differential diagnosis of extrahepatic biliary obstruction and whenever surgical treatment of chronic pancreatitis is contemplated.  相似文献   
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We developed a joint bioaugmentation and biostimulation approach for the clean up of soil contaminated with high (168.7 and 337.4 microg g(-1)) concentrations of the herbicide atrazine (2-chloro-4-(ethylamino)-6-isopropylamino-s-triazine). Pseudomonas sp. strain ADP (P. ADP) was used for bioaugmentation (approximately 10(7) cells g(-1) soil), and citrate (concentration range 5.8-40 mg g(-1) soil) and succinate (6.2-30.8 mg g(-1)) were used for biostimulation. The study soil had indigenous potential for atrazine mineralization (54.4 +/- 2% of 168.7 microg g(-1) mineralized after 67 day), but rapid mineralization only took place after a prolonged acclimation phase (approximately 28 days). Inoculation with P. ADP alone resulted in a limited improvement in mineralization (e.g., 30.6 +/- 1% mineralization of 168.7 microg g(-1) of atrazine in inoculated soil cf. < 0.5% in noninoculated in 7 days). Quantification of surviving numbers of P. ADP revealed a 10-fold decline from initial levels. However, bioaugmentation together with citrate or succinate biostimulation markedly increased P. ADP cell survival and atrazine mineralization (e.g., addition of 11.6 mg g(-1) of citrate increased mineralization of 337.4 microg g(-1) of atrazine from < 2 to 79.9 +/- 1% in 13 days). A critical parameter in determining the extent of atrazine mineralization by P. ADP was C(s):N(atz) (soluble carbon to atrazine nitrogen ratio): C(s):N(atz) > 40 was required for maximal atrazine mineralization. We suggest our observations may be used as a framework for rational bioremediation of field soils contaminated with atrazine.  相似文献   
48.
Estrogen content of dairy and swine wastes   总被引:3,自引:0,他引:3  
Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentrations in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17beta-estradiol (E2), estrone (E1), and 17alpha-estradiol by gas chromatography-mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to areal mass application rates of estrogen to fields. Swine farrowing waste (from farrowing sows and piglets) had the highest ratios of E2 to macronutrients. Mean ratios in swine farrowing waste were roughly twice those in swine finishing waste (from growing male and nonpregnant female animals) and more than four times higher than those in dairy waste (from lactating cows in various stages of their reproductive cycles); these differences were statistically significant (alpha = 0.05). Estrone followed a similar trend. In contrast, ratios of 17alpha-estradiol to macronutrients were highest in dairy operations. These results can be used to better predict estrogen loading rates on fields receiving swine and dairy wastes.  相似文献   
49.
The dominant sources of the petrogenic hydrocarbon background in benthic sediments of Prince William Sound, AK (PWS), site of the 1989 Exxon-Valdez oil spill, are eroding Tertiary shales and residues of natural oil seepage. Mass balance considerations and statistical analyses of hydrocarbon fingerprints independently indicate that coal contributes generally less than 1% of the polycyclic aromatic hydrocarbons (PAH) and chemical biomarkers in this background. This is environmentally significant because of presumed differences in the bioavailability of PAH in coal, seep oil residues, and shales. Coal particles are present in PWS sediments, but their PAH and chemical biomarker contributions are overwhelmed by those of seep oil residues and organic particles from shales of low-to-high thermally maturity. In the late Tertiary or early Quaternary, the currently exposed and eroding shale formations were heated into the oil-generation window and, consequently, are now relatively rich in extractable PAH and chemical biomarkers. The exposed and eroding coals in the area, in contrast, experienced long hot burial and are now thermally overmature with respect to oil generation. The concentrations of thermally sensitive PAH and biomarker compounds in PWS sediments are not consistent with a mature coal origin but are consistent with the low-to-high maturity shales and seep oils in the area.  相似文献   
50.
Litigation and regulatory assaults on the tobacco companies may create a willingness among tobacco manufacturers to bargain resources and acceptance of public policy changes for limitations of liability, as has been seen by the recent settlement with the Liggett Group. Two elements absolutely critical to any plan are the elimination of tobacco advertising and promotion and the removal of addiction as a reason for tobacco use. Minimal components of any settlement should include: (a) acceptance by the tobacco manufacturers of the causal relationship between tobacco use and disease, and the addictive nature of nicotine; (b) a total ban on tobacco advertising and promotion; (c) FDA jurisdiction over tobacco products and their nicotine content, with the intent of removing nicotine as soon as acceptable nicotine substitution products are available; (d) reimbursement to the states for Medicaid and other state expenditures attributable to smoking, to the maximum extent feasible; (e) funding for local, state, and federal programmes and research in tobacco control; (f) acceptance of legislation and regulations protecting the right of non-smokers to breathe air free of tobacco smoke; (g) funding for a large, national, media-led, anti- tobacco campaign; and (h) cessation assistance for addicted smokers. If negotiations toward a settlement proceed, it is essential that the public health community participate in defining the elements of any agreement to ensure that whatever agreement develops is focused on reducing tobacco-related disease rather than continuing the profitability of American tobacco companies. That participation requires articulation of the core elements essential to an acceptable agreement. If resolution of the public health issues surrounding continued sale of tobacco products can be reached in the United States, it may provide a model for similar resolution in other countries.


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