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41.
Twenty new cases of Silo filler's disease (SFD) have been collected, documenting the incidence and clinical features of exposure to nitrogen oxides present in freshly filled silos. Cases of SFD were identified using a statewide computerized discharge diagnosis system. Fifteen of these were identified in the index period, allowing us to calculate an approximate annual incidence of 5.0 cases/100,000 silo-associated farm workers/yr in New York State. All cases occurred during harvest periods, with 80% in September and October. Corn silage was the gas source in 18 (90%). All cases involved young white men (mean age, 31.5 yr). The most common presenting feature was dyspnea. All victims entered a silo during the peak danger period, and only one used recommended ventilation techniques. Four cases ended in death (20% mortality). Silo filler's disease, although rare, is a potentially devastating disease involving otherwise young, healthy farm workers. It is readily prevented. 相似文献
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P J May H Baker P P Vidal R F Spencer R Baker 《The Journal of comparative neurology》1987,266(2):150-170
Serotoninergic fibers have been reported in both the abducens and facial nuclei of the cat. Furthermore, serotoninergic dorsal raphe and oculomotor internuclear neurons occupy similar locations in the periaqueductal gray overlying the oculomotor and trochlear motor nuclei. To resolve the issue of whether these two populations of neurons overlap, serotoninergic fibers were assayed in the abducens and facial nucleus; then the morphologies and distributions of identified serotoninergic neurons and oculomotor internuclear neurons were determined. Both the abducens and facial nuclei contained varicosities labelled with antibody to serotonin, but a much higher density of immunoreactive fibers was present in the latter, especially in its medial aspect. Distinct synaptic profiles labelled with antibodies to serotonin were observed in both nuclei. In both cases, terminal profiles contained numerous small, predominantly spheroidal, synaptic vesicles as well as a few, large, dense-core vesicles. These profiles made synaptic contacts onto dendritic and, in the facial nucleus, somatic profiles that occasionally displayed asymmetric, postsynaptic, membrane densifications. Following injection of horseradish peroxidase into either the abducens or facial nuclei, double-label immunohistochemical techniques demonstrated that the serotoninergic and oculomotor internuclear neurons form two distinct cell populations. The immunoreactive serotoninergic cells were distributed within the dorsal raphe nucleus, predominantly caudal to the retrogradely labelled oculomotor internuclear neurons. The latter were located in the oculomotor nucleus along its dorsal border and in the adjacent supraoculomotor area. Intracellular injection of horseradish peroxidase revealed that oculomotor internuclear neurons have multipolar somata with up to ten long, tapering dendrites that bifurcate approximately five times. Their dendritic fields were generally contained within the nucleus and adjacent supraoculomotor area. In contrast, putative serotoninergic neurons were often spindle-shaped and exhibited far fewer primary dendrites. Many of these long, narrow, sparsely branched dendrites crossed the midline and extended to the surface of the cerebral aqueduct. In the vicinity of the aqueduct they branched repeatedly to form a dendritic thicket. The axons of the intracellularly stained serotoninergic neurons emerged either from the somata or the end of a process with dendritic morphology, and in some cases they produced axon collaterals within the periaqueductal gray. Thus the oculomotor internuclear and serotoninergic populations differ in both distribution and morphology.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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45.
本文应用ABC法对30例尖锐湿疣(CA)和30例宫颈癌(CCU)进行原位观察,分析对比两者浸润单一核细胞(MNC)的亚群组成、分布及活化状态。结果提示,两者局部免疫均受抑制,而以宫颈癌为甚。依此本文对不同类型HPV相关疾病的局部免疫反应状态及宿主对不同型别HPV感染的免疫反应进行探讨。 相似文献
46.
47.
Cytokine profiles of patients infected with Mycobacterium ulcerans and unaffected household contacts 总被引:4,自引:0,他引:4
Gooding TM Johnson PD Smith M Kemp AS Robins-Browne RM 《Infection and immunity》2002,70(10):5562-5567
Mycobacterium ulcerans, the cause of Buruli ulcer, is an environmental mycobacterium with a distinct geographic distribution. The reasons why only some individuals who are exposed to M. ulcerans develop ulcers are not known but are likely to reflect individual differences in the immune response to infections with this bacterium. In this study, we investigated cytokine profiles of peripheral blood mononuclear cells (PBMC) from 23 Buruli ulcer patients and 25 household contacts in a region of Australia where Buruli ulcer is endemic. The results showed that following stimulation with M. ulcerans or Mycobacterium bovis BCG, PBMC from Buruli ulcer patients mounted a Th2-type response, which was manifested by the production of mRNA for interleukin 4 (IL-4), IL-5, IL-6, and IL-10, whereas unaffected contacts responded mainly with the Th1 cytokines gamma interferon (IFN-gamma) and IL-12. For example, mRNA for IL-4 was detected in 18 of 23 patients but in only 3 of 25 control subjects (P < 0.0001). By contrast, PBMC from 21 of 25 unaffected individuals produced IFN-gamma compared with 3 of 23 patients (P < 0.0001). IFN-gamma release following stimulation with mycobacteria was markedly reduced in affected subjects. Frequencies of antibodies to M. ulcerans in serum samples from affected and unaffected subjects were similar, indicating that many of the control subjects had been exposed to this bacterium. Together, these findings suggest that a Th1-type immune response to M. ulcerans may prevent the development of Buruli ulcer in people exposed to M. ulcerans, but a Th-2 response does not. 相似文献
48.
Extremely complex repeat shuffling during germline mutation at human minisatellite B6.7 总被引:8,自引:0,他引:8
Human minisatellite B6.7 is a highly variable locus showing extensive heterozygosity with alleles ranging from six to >500 repeat units. Paternal and maternal mutation rates to new length alleles were estimated from pedigrees at 7.0 and 3.9% per gamete, respectively, indicating that B6.7 is one of the most unstable minisatellites isolated to date. Mutation at this locus was also analysed by small pool PCR of sperm and blood DNA. Male germline instability varied from <0.8 to 14% per allele and increased with tandem array size. In contrast, the frequency of mutants in somatic (blood) DNA was far lower (<0.5%), consistent with a meiotic origin of germline mutants. Sperm mutants were further characterized by minisatellite variant repeat mapping using four major polymorphic sites within the B6.7 repeats. This highly informative system revealed a wide variety of changes in allele structure, including simple intra-allelic duplications and deletions and more complicated inter- and intra-allelic transfers of repeat blocks, as seen at other human minisatellites. The main mode of sperm mutation, however, resulted in extremely complex allele reorganization with evidence of inter-allelic transfer plus the generation of novel repeats by rearrangement at the sub-repeat level, suggesting that recombinational instability at B6.7 is a complex multistep process. 相似文献
49.
Michael W Si John A Thorson Gregory Y Lauwers Paola DalCin Jaime Furman 《Diagnostic molecular pathology》2004,13(3):183-189
OBJECTIVE: Lymphoepithelioma-like carcinoma (LELC) is an undifferentiated carcinoma with a dense lymphoid stroma. It has been reported in diverse organs and shows variable association with Epstein-Barr virus (EBV). Only a few EBV positive cases have been observed in the hepatobiliary system, all of which were considered to be cholangiocarcinomas. We report a unique case of hepatocellular LELC arising in a cirrhotic liver with EBV demonstrated in the tumor cells. METHODS AND RESULTS: A 39-year-old Hispanic female underwent an orthotopic liver transplant for end stage liver disease secondary to chronic hepatitis C. A high-grade hepatocellular carcinoma with a dense lymphocytic infiltrate was found in the explant as well as in a portal lymph node. Three months posttransplant, the patient developed numerous hepatic nodules with enlarged periaortic and portacaval lymph nodes. Biopsy of the hepatic nodules showed a recurrent hepatocellular carcinoma devoid of a dense lymphocytic infiltrate. Both the primary and recurrent tumors were positive for EBV by molecular studies. The patient eventually expired from liver failure over a 6-week period. CONCLUSION: This case represents the first report of EBV-positive hepatocellular LELC. It is particularly interesting given the precipitous clinical outcome, which was possibly related to immunosuppresive therapy. 相似文献
50.
Analysis of the mechanism of lipoprotein(a) assembly 总被引:2,自引:0,他引:2
Marlys L. Koschinsky Santica M. Marcovina Lorraine F. May Brent R. Gabel 《Clinical genetics》1997,52(5):338-346
We have assessed the ability of a battery of purified recombinant apolipoprotein(a) (r-apo(a)) derivatives to bind to immobilized low-density lipoprotein (LDL) by ELISA. Removal of the apo(a) kringle IV type 8 and type 9 sequences dramatically reduced apo(a) binding to LDL. The binding of apo(a) to LDL was effectively inhibited by arginine, lysine, the lysine analogue ε-aminocaproic acid and proline; comparable inhibition was observed using the 17K and KIV5–8 r-apo(a) derivatives, suggesting a direct role for sequences contained in the latter species in mediating the initial non-covalent interactions which precede specific disulfide bond formation. We also determined that r-apo(a) binds directly to a synthetic apoB peptide spanning amino acid residues 3732–3745; this interaction appeared to be mediated by sequences present in apo(a) kringle IV types 8 and 9, and could be inhibited by arginine, lysine and proline. The results of this study indicate that the efficiency of Lp(a) assembly is a direct function of the initial non-covalent interactions between apo(a) and LDL; in addition, these studies suggest that Cys3734 in apoB mediates covalent linkage with apo(a) by virtue of the ability of the apoB sequences surrounding this residue to directly interact with apo(a) KIV type 9. 相似文献