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1.
Maternal orbital hematoma associated with labor   总被引:1,自引:0,他引:1  
We examined two women with orbital hematomas that occurred during labor. Both women developed sudden diplopia, proptosis, and orbital pain. The location of the hematoma was confirmed by orbital echography and computed tomography. The patients were observed without surgical intervention. Neither patient developed clinical or echographic signs of compressive optic neuropathy. Clinical resolution occurred during the following two weeks. Serial standardized orbital echographic examinations documented resolution of the hematomas.  相似文献   
2.
Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
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3.
W Johnson  L Varner    M Poch 《Infection and immunity》1991,59(7):2376-2381
Legionella pneumophila has been shown to survive and multiply in a variety of intracellular environments, including protozoa and human mononuclear phagocytes. However, the mechanism by which this organism acquires iron in the intracellular environment has not been studied. Since L. pneumophila does not produce siderophores, alternative methods of iron acquisition were investigated. Virulent strains of L. pneumophila were able to grow in media containing as little as 3 microM iron, whereas avirulent cells required a minimum of 13 microM iron for growth. Neither virulent nor avirulent cells were able to utilize 55Fe bound to transferrin. When incubated in the presence of 55Fe in the form of ferric chloride, both virulent and avirulent cells accumulated equal amounts of iron. The uptake of iron was energy dependent as indicated by inhibition of 55Fe uptake at 4 degrees C and preincubation of the cells with KCN. Treatment of virulent cells with pronase or trypsin had no effect on iron uptake. In contrast, pronase or trypsin treatment of avirulent cells resulted in increased uptake of iron. Iron reductase activity in both virulent and avirulent cells was demonstrated, with the highest specific activity associated with the periplasmic fraction. Maximum reductase activity of virulent cells occurred with NADH as the reductant. In contrast, avirulent cells showed a twofold increase in enzyme activity when NADPH was used as the reductant. These results suggest that an iron reductase is important in iron acquisition by L. pneumophila.  相似文献   
4.
The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi- probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.   相似文献   
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Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
7.
Evaluation of treatment modalities, including pharmacotherapy, for organic brain syndrome (OBS) has been difficult because of sampling and methodological problems, and comparisons of research studies are all but impossible. In this study, an ergot derivative, a combination of dihydroergocornine mesylate, dihydroergocristine mesylate, and dihydroergokryptine mesylate (Hydergine) was compared with placebo, using a double-blind technique in a sample of nursing home residents with evidence of OBS. An 18-category symptom rating scale was used for periodic assessment over a six-month interval. Comparisons of the two groups of subjects disclosed that the Hydergine-treated group showed statistically significantly more improvement in most of the variables measured, especially during the last three months of treatment. Furthermore, sophisticated analysis revealed that positive changes in cognitive function cannot be accounted for as a mere reflection, or "halo" effect, associated with improved mood and general sense of well-being.  相似文献   
8.
We examined the relationship between a functional polymorphism (667C-- >T, ala-->val) of the methylenetetrahydrofolate reductase gene (MTHFR) and the risk of colorectal adenomas in the prospective Nurses' Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval (CI) 0.84-2.17] was not significantly associated with risk of adenomas. This lack of association was observed for both small (RR = 1.36, 95% CI 0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore, there was no significant interaction between this polymorphism and consumption of either folate, methionine or alcohol. We also examined the relationship of a newly identified polymorphism (asp919gly) of the methionine synthase gene (MS) with the risk of colorectal adenomas in the same population. The MS gly/gly polymorphism was also not significantly associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70). These results, which need to be confirmed in other studies, suggest that the MTHFR val/val polymorphism, which has been previously inversely associated with risk of colorectal cancer, plays a role only in a late stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may protect against malignant transformation in the subset of benign adenomas, which may progress to malignancy.   相似文献   
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10.
Seventy hospitalized women were entered into an open, randomized, parallel study of antimicrobial prophylaxis for abdominal and vaginal hysterectomy with the use of either cefotetan, a new long-acting cephalosporin, or cefoxitin. Ninety-four percent of cefotetan recipients and 83% of cefoxitin recipients did not develop clinical signs or symptoms of infection. The satisfactory bacteriologic response rates were significantly different: 91% satisfactory (43 of 47 patients) for cefotetan and 74% satisfactory (17 of 23 patients) for cefoxitin. The two treatment groups demonstrated no significant differences in postoperative temperature changes, duration of hospitalization, or grading of surgical wounds. Neither drug was associated with significant side effects.  相似文献   
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