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1.
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.  相似文献   
2.
Background: Short administration of volatile anesthetics preconditions myocardium and protects the heart against the consequences of subsequent ischemia. Activation of tyrosine kinase is implicated in ischemic preconditioning. The authors investigated whether desflurane-induced preconditioning depends on activation of tyrosine kinase.

Methods: Sixty-four rabbits were instrumented for measurement of left ventricular pressure, cardiac output, and myocardial infarct size (IS). All rabbits were subjected to 30 min of occlusion of a major coronary artery and 2 h of subsequent reperfusion. Rabbits underwent a treatment period consisting of either no intervention for 35 min (control group, n = 12) or 15 min of 1 minimum alveolar concentration desflurane inhalation followed by a 10-min washout period (desflurane group, n = 12). Four additional groups received the tyrosine kinase inhibitor genistein (5 mg/kg) or lavendustin A (1.3 mg/kg) at the beginning of the treatment period with (desflurane-genistein group, n = 11; desflurane-lavendustin A group, n = 12) or without desflurane inhalation (genistein group, n = 9; lavendustin A group, n = 8).

Results: Hemodynamic values were similar in all groups during baseline (left ventricular pressure, 87 +/- 14 mmHg [mean +/- SD]; cardiac output, 198 +/- 47 ml/min), during coronary artery occlusion (left ventricular pressure, 78 +/- 12 mmHg; cardiac output, 173 +/- 39 ml/min), and after 2 h of reperfusion (left ventricular pressure, 59 +/- 17; cardiac output, 154 +/- 43 ml/min). IS in the control group was 55 +/- 10% of the area at risk. The tyrosine inhibitors had no effect on IS (genistein group, 56 +/- 13%; lavendustin A group, 49 +/- 13%; each P = 1.0 vs. control group). Desflurane preconditioning reduced IS to 40 +/- 15% (P = 0.04 vs. control group). Tyrosine kinase inhibitor administration had no effect on IS reduction (desflurane-genistein group, 44 +/- 13%; desflurane-lavendustin A group, 44 +/- 16%; each P = 1.0 vs. desflurane group).  相似文献   

3.
We have developed a PCR-based method to detect macrolide resistance and the virulence gene cagA in Helicobacter pylori within 24 h, thereby improving the lengthy process of culture-based approaches. Total DNA was prepared directly from stomach biopsy specimens. The procedure proved to be rapid and reliable and could be utilized for diagnostic purposes.  相似文献   
4.
Summary A 37-year-old man with severe transfusion-requiring anemia and neutropenia associated with lymphocytosis of large granular lymphocytes (LGLs) has been followed over a period of 3.5 years. Detailed phenotyping of the LGL has been performed, revealing a phenotype of CD3+, CD8+, CD16+, HLA-DR+, and Leu-7+. Southern-blot analysis of the T-cell receptor beta-chain locus detected a gene rearrangement, thus providing proof of monoclonality of the peripheral blood LGLs.Abbreviations CD Cluster of differentiation - LGLs Large granular lymphocytes - PBMCs Peripheral blood mononuclear cells  相似文献   
5.
A cloned murine T cell line, KIII5, specific for the polypeptide poly-L(Tyr,Glu)-poly-D,L-Ala--poly-L-Lys [(T,G)-A--L] was compared at different stages after antigenic stimulation with respect to the conditions required for the reinduction of growth by varying concentrations of antigen presented on different types of accessory cells (AC). We show that the dose of antigen necessary for inducing half maximal proliferation in the presence of splenic AC shifts to considerably lower concentrations when the T cell blasts revert to a resting state (100 micrograms/ml on day 7 to 10 micrograms/ml on day 21-35). During the same time period the expression of interleukin 2 (IL2) receptor and the reactivity to IL2 decline. However, no direct correlation between the increasing sensitivity to antigen and the decreasing reactivity to IL2 appears to exist. With peritoneal AC "early" T cells (day 7) did not respond to (T,G)-A--L at all, but in the course of "aging" responsiveness increased and finally reached the same level as in the presence of splenic AC, although at a higher antigen dose (100 micrograms/ml on day 35-45). Furthermore, the antigen-induced proliferation of "aging" T cells became more resistant to inhibition both by anti-L3T4 and anti-T cell receptor antibodies. Two alternative interpretations of these data are possible: antigen-activated T cells, while gradually reverting to a resting state, interact more avidly with antigen-presenting cells or the triggering threshold of the T cells is decreasing.  相似文献   
6.
Summary Diagnosis of malignant histiocytosis (MH) was confirmed in 16 patients. Stage at diagnosis was I–II in nine, and III–IV in seven patients. Poor prognosis and B-symptoms were correlated to advanced stages. Bone marrow biopsy proved most useful to verify organ involvement. Scintigraphy and computerized tomography, too, detected organ involvement in some patients and were helpful for judging response to therapy. Relapses after radiotherapy were frequent. Polychemotherapy using CHOP-combination is recommended for most patients and may in stages I–II be supplemented by primary or secondary involved or extended field irradiation and in more advanced stages by mainbulk-irradiation. The value of prophylactic CNS-therapy remains controversial. Pathophysiological aspects and differential diagnosis are discussed.  相似文献   
7.
Zusammenfassung Eine optimale Behandlung des Hodgkin-Patienten setzt die Kenntnis des Ausbreitungsstadiums voraus. Laboruntersuchungen, Röntgen und Nuklearmedizin reichen gewöhnlich nicht aus, um dies mit ausreichender Sicherheit festzustellen. Es sind in der Regel Biopsien von Knochenmark und Leber erforderlich. In besonderen Fällen werden auch eine Laparoskopie oder explorative Laparotomie und Splenektomie empfohlen. Als optimale Therapie tritt in den auf Lymphknotenregionen beschränkten Ausbreitungsstadien die Strahlentherapie in den Vordergrund, bei ausgeprägten Allgemeinsymptomen und bei Organbefall eine zytostatische Behandlung. Diagnostik und Therapie sollten individuell gehandhabt werden. Neue therapeutische Vorstellungen müssen kritisch an den z.T. hervorragenden Ergebnissen gemessen werden, die von verschiedenen Arbeitsgruppen erreicht wurden.Herrn Professor Dr. Dr. h. c. H.E. Bock zum 75. Geburtstag in Verehrung und Dankbarkeit gewidmet  相似文献   
8.
9.
During the summer of 2003, an outbreak of human monkeypox occurred in the Midwest region of the United States. In all, 52 rodents suspected of being infected with monkeypox virus were collected from an exotic pet dealer and from private homes. The rodents were euthanized and submitted for testing to the United States Army Medical Research Institute of Infectious Diseases by the Galesburg Animal Disease Laboratory, Illinois Department of Agriculture. The rodent tissue samples were appropriately processed and then tested by using an integrated approach involving real-time polymerase chain reaction (PCR) assays, an antigen-detection immunoassay, and virus culture. We designed and extensively tested two specific real-time PCR assays for rapidly detecting monkeypox virus DNA using the Vaccinia virus F3L and N3R genes as targets. The assays were validated against panels of orthopox viral and miscellaneous bacterial DNAs. A pan-orthopox electrochemiluminescence (ECL) assay was used to further confirm the presence of Orthopoxvirus infection of the rodents. Seven of 12 (58%) animals (seven of 52 (15%) of all animals) tested positive in both monkeypox-specific PCR assays and two additional pan-orthopox PCR assays (in at least one tissue). The ECL results showed varying degrees of agreement with PCR. One hamster and three gerbils were positive by both PCR and ECL for all tissues tested. In addition, we attempted to verify the presence of monkeypox virus by culture on multiple cell lines, by immunohistology, and by electron microscopy, with negative results. Sequencing the PCR products from the samples indicated 100% identity with monkeypox virus strain Zaire-96-I-16 (a human isolate from the Congo). These real-time PCR and ECL assays represent a significant addition to the battery of tests for the detection of various orthopoxviruses. In light of the recent monkeypox virus transmissions, early detection of the virus is crucial for both natural outbreaks and potential acts of bioterrorism.  相似文献   
10.
Abstract: A variety of reasons related to the HLA class I system has complicated the application of molecular approaches to HLA class I typing. Here we present a PCR-based HLA-A typing strategy considering the sequence variations of the two most polymorphic exons which allows complete subtyping of the HLA-A locus. The method is based on a sequence-specific amplification identifying the serologically defined HLA-A specificities. The PCR products generated by these group-specific primers bear the sequence information necessary for a postamplification specificity step. The primer pairs are located within one exon, either exon 2 or exon 3, which avoids amplification of polymorphic intron sequences allowing subsequent single-strand conformation polymorphism analysis and facilitating direct sequencing. Using this method we investigated 48 cell lines and 153 clinical samples. 23 PCR reactions are performed per individual for the assignment of the serological specificities A1-A80. The reproducibility was 100% in all cell lines and 85 clinical samples typed on two separate occasions. With the exception of 13 out of 231 possible serological combinations all homozygous and heterozygous combinations of A1-A80 can be distinguished by specific amplification patterns. Comparing the PCR based typing results with those of serology in 12% a discrepancy was found. Solid-phase sequencing or SSCP analysis of the group-specific PCR fragments allowed complete subtyping of the HLA-A locus. This strategy can identify all 48 HLA-A alleles based on the sequence variations of the 2nd and 3rd exon. 1128 homozygous and heterozygous allele combinations are possible for the HLA-A locus. Only 4 out of these 1128 allele combinations remained unresolved.  相似文献   
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