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981.
982.
983.
In the present study we examined the effects of prenatal manganese (Mn) intoxication on [3H]glucose uptake in the brain of rats lesioned as neonates with 6-hydroxydopamine (6-OHDA). MnCl2 ? 4H2O (10,000 ppm) was added to the drinking water of pregnant Wistar rats for the duration of pregnancy. On the day of parturition, Mn was discontinued as an additive to the drinking water. The control group consisted of rats that consumed water without Mn. Three days after birth, rats in both groups (control and Mn) were pretreated with desipramine hydrochloride (20 mg/kg) and pargyline hydrochloride (50 mg/kg) and injected bilaterally icv with one of three doses of 6-OHDAhydrobromide (15 μg, 30 μg or 67 μg base form in saline on each side) or with saline (control). 6-[3H]-Dglucose (500 μCi/kg, ip) was administered to male offspring in adulthood; after 15 min, brain specimens were taken (frontal cortex, hippocampus, striatum, thalamus with hypothalamus, pons and cerebellum) for determination of radioactivity in a liquid scintillation counter. Low dose 6-OHDA (15 μg icv) increased [3H]glucose uptake in all brain regions (p < 0.05) in both control and Mnintoxicated animals. In rats lesioned with a moderate dose of 6-OHDA(30 μg icv), [3H]glucose uptake was unaltered in both control and Mn-exposed rats. High dose 6-OHDA(67 μg icv) reduced [3H]glucose uptake in all brain regions of Mn-exposed rats (except for cerebellum) compared with the saline group (all, p < 0.05). There was no change in regional brain uptake of [3H]glucose in control rats. In conclusion, this study shows that mild neuronal insult (15 μg icv 6-OHDA) increased glucose uptake in the brain while severe damage (concomitant 60 μg icv 6-OHDA and Mn treatment) significantly diminished this process. 相似文献
984.
985.
In the population the annual incidence of pulmonary embolism amounts to 1.3-2.8 per 1000 at the age of 65-89 years. Mortality reaches about 17% within the first 3 months. Acute pulmonary embolism is characterized by an increase in pulmonary arterial pressure and an impairment of the pulmonary gas exchange. Elevation of the right cardiac pressure up to right heart decompensation may follow. In addition, hypoxemia, hyperventilation, dead space ventilation, right to left shunting, bronchoconstriction, and vasoconstriction may occur. Clinical examination, ECG, laboratory findings such as elevated D-dimer, blood gas analysis, ultrasound examination of the veins of the lower extremities, and transthoracic echocardiography are acutely available diagnostic methods of an emergency department. In addition, extensive diagnostic procedures like pulmonary scintigraphy and pulmonary angiography may be required. The aim is to get a definite diagnosis as quickly as possible to direct therapy. In acute pulmonary embolism with cardiac shock, monitoring and stabilization of the circulatory function as well as an appropriate anticoagulant therapy are essential. In some cases surgery or a local fibrinolytic intervention is indicated. 相似文献
986.
987.
988.
Demmeler M Nowak D Schierl R 《International archives of occupational and environmental health》2009,82(4):539-542
Introduction Recreational shooting in indoor firing ranges is very popular in Germany. Lead-containing ammunition is still in use. Therefore
we checked the blood lead levels (BLL) from 129 subjects doing several types of shooting disciplines.
Methods In total, BLLs of 129 shooters (nine female) from 11 different shooting ranges with a mean age of 49 years were measured.
The blood samples were taken after the volunteers had given written informed consent. Determination of lead was carried out
by graphite furnace atomic absorption (GF-AAS) under strict internal and external quality control schemes.
Results While individuals shooting only with airguns (n = 20) showed a median BLL of 33 μg/l (range 18–127 μg/l), those who were also users of .22 lr weapons (n = 15) turned out to have a median of 87 μg/l (range 14–172 μg/l). Shooters of .22 lr and large calibre handguns (9 mm or
larger) (n = 51) had median 107 μg/l (range 27–375 μg/l) and those only using large calibre handguns (n = 32) had median 100 μg/l (range 28–326 μg/l). The IPSC-group (n = 11) had the highest median with 192 μg/l (range 32–521 μg/l).
Conclusion Our results show clearly that many shooters have high blood levels; some of them are still exceeding threshold limit values
(TLVs) for lead exposed workers. Especially for younger women there is a high potential risk if they become pregnant. So there
is a clear need for improving the situation whether by use of lead-free ammunition or by better ventilation systems. 相似文献
989.
Chow KU Nowak D Trepohl B Hochmuth S Schneider B Hoelzer D Mitrou PS Bergmann L Ottmann OG Boehrer S 《Leukemia & lymphoma》2007,48(7):1379-1388
The aminopyrimidine inhibitor AMN107 (Nilotinib) was rationally designed to antagonize the aberrant tyrosine kinase activity of Bcr-Abl-positive cells. We here evaluated, whether AMN107 is also able to induce apoptosis in Bcr-Abl-negative cells of lymphatic origin. The B-cell lines DOHH-2 and WSU-NHL and the T-cell lines Jurkat and HUT78 were incubated with increasing amounts of AMN107 corresponding to clinically achievable dosages. Subsequently, induced molecular changes were assessed by FACS analysis, Western blot, and enzyme activity assays. Although AMN107 exhibited only a minor apoptosis-inducing effect in the T-cell lines, it exerted a considerable, dose-dependent cytotoxicity in the B-cell lines. Using selective caspase-inhibitors, we show that apoptosis in responder cell lines critically relies on activation of caspase-6 and caspase-9. Cell lines sensitive and resistant towards AMN107 can be discriminated by their differential expression of Src-kinases. Although the AMN107-sensitive cell lines DOHH-2 and WSU-NHL exhibited low or no expression of the Src-kinases Lck, phosphorylated Lck, and Yes with a concomitant high expression of Hck, Lyn, and phosphorylated Lyn, the expression pattern of these kinases was inverse in the AMN107-resistant T-cell lines. In conclusion, this is the first report providing evidence that activity of AMN107 is not restricted to Bcr-Abl, c-Kit, or PDGFR-positive cells, but also extends to lymphatic cell lines of B-cell origin. 相似文献
990.