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91.
The popular "Cross-hatch" method of CO2 laser surgery is compared with the "blister" technique of verrucae destruction. The blister technique provides greater reliability of wart tissue destruction through better visualization of normal skin lines and verrucoid tissue. The procedure can be performed quickly and easily, and is less painful to the patient than other conventional methods of wart destruction. 相似文献
92.
Markus Riederer Jörg Schönherr 《Archives of environmental contamination and toxicology》1988,17(1):21-25
The epoxy groups contained in the cuticles of some plant species covalently bind residues of chemicals having a carboxyl function. This may lead to an increased persistence of these compounds in the environment. In order to assess the ecotoxicological potential of this reaction, an analytical method for the determination of cuticular epoxides was developed. Stable derivatives can be quantitatively formed by treating cuticles with 0.2M HC1 in 1,4-dioxane. This reaction leads to the formation of the corresponding chlorohydrins. It proceeds rapidly and without side-effects both in isolated cuticles andin situ. The derivatives can be analyzed by standard thin-layer and capillary gas Chromatographic methods. Electron impact and chemical ionization mass spectrometry was used to identify the chlorohydrins derived fromClivia andFicus leaf cutin. 相似文献
93.
Functional analysis of the cag pathogenicity island in Helicobacter pylori isolates from patients with gastritis, peptic ulcer, and gastric cancer 总被引:9,自引:0,他引:9 下载免费PDF全文
Backert S Schwarz T Miehlke S Kirsch C Sommer C Kwok T Gerhard M Goebel UB Lehn N Koenig W Meyer TF 《Infection and immunity》2004,72(2):1043-1056
Helicobacter pylori is the causative agent of a variety of gastric diseases, but the clinical relevance of bacterial virulence factors is still controversial. Virulent strains carrying the cag pathogenicity island (cagPAI) are thought to be key players in disease development. Here, we have compared cagPAI-dependent in vitro responses in H. pylori isolates obtained from 75 patients with gastritis, peptic ulcer, and gastric cancer (n = 25 in each group). AGS gastric epithelial cells were infected with each strain and assayed for (i) CagA expression, (ii) translocation and tyrosine phosphorylation of CagA, (iii) c-Src inactivation, (iv) cortactin dephosphorylation, (v) induction of actin cytoskeletal rearrangements associated with cell elongation, (vi) induction of cellular motility, and (vii) secretion of interleukin-8. Interestingly, we found high but similar prevalences of all of these cagPAI-dependent host cell responses (ranging from 56 to 80%) among the various groups of patients. This study revealed CagA proteins with unique features, CagA subspecies of various sizes, and new functional properties for the phenotypic outcomes. We further showed that induction of AGS cell motility and elongation are two independent processes. Our data corroborate epidemiological studies, which indicate a significant association of cagPAI presence and functionality with histopathological findings in gastritis, peptic ulcer, and gastric cancer patients, thus emphasizing the importance of the cagPAI for the pathogenicity of H. pylori. Nevertheless, we found no significant association of the specific H. pylori-induced responses with any particular patient group. This may indicate that the determination of disease development is highly complex and involves multiple bacterial and/or host factors. 相似文献
94.
Zipfel S Schneider A Wild B Löwe B Jünger J Haass M Sack FU Bergmann G Herzog W 《Psychosomatic medicine》2002,64(5):740-747
OBJECTIVE: This study explored the value of preoperative self-reported assessment for depression and anxiety in patients who had undergone heart transplantation (HTx). The initial sample was divided into subgroups of patients with ischemic (ICMP) and dilated cardiomyopathy (DCMP). Patient depression and anxiety scores were measured in both subgroups and their impact on pre- and postoperative mortality investigated. METHOD: An initial sample of 152 patients with either ICMP (N = 57) or DCMP (N = 95) and end-stage heart disease awaiting heart transplantation were assessed in a multidimensional longitudinal study, including psychological and somatic variables. One hundred and three patients received a HTx and were followed up for a mean of 4.4 years. Proportional hazard models were computed to test for the influence of psychosocial and somatic factors on outcome. RESULTS: Preoperative depression and state anxiety scores were significantly higher in the ICMP group. In addition to donor and recipient age, ICMP patients in the preoperative high depression group also showed a significantly higher mortality after HTx. This result remained significant even after controlling for sociodemographic and somatic variables. CONCLUSIONS: Patient self-reported depression, but not anxiety, can contribute to the identification of subgroups of patients with an unfavorable outcome after HTx. It therefore may be helpful to screen for depression, particularly in patients with an ischemic cause of their end-stage heart disease. Specific intervention programs should be further developed and evaluated. 相似文献
95.
Laska M Fendt M Wieser A Endres T Hernandez Salazar LT Apfelbach R 《Physiology & behavior》2005,84(2):211-215
2,4,5-trimethylthiazoline (TMT) is a volatile component of the anal gland secretion of the red fox and elicits behavioral and physiological fear responses in the rat. Using instrumental conditioning paradigms, we determined olfactory detection thresholds for TMT in three rats, a natural prey species of the red fox, and compared their performance to that of three squirrel monkeys, three spider monkeys and four pigtail macaques, all non-prey species of the red fox. We found that the rats were able to discriminate concentrations between 0.04 and 0.10 ppt (parts per trillion) of TMT from the odorless solvent which is by far the lowest olfactory detection threshold for an odorant reported in rats so far. In contrast, the spider monkeys needed 0.14-1.38 ppb (parts per billion), the pigtail macaques 0.41-4.07 ppb, and the squirrel monkeys 4.07-13.80 ppb to detect TMT which does not rank among the lowest olfactory thresholds reported for these three primate species. Thus, these results support the assumption that the behavioral relevance of an odorant may be an important determinant of a species' olfactory sensitivity. 相似文献
96.
Renate A. Morawetz G. Paolo Rizzardi Didier Glauser Olivier Rutschmann Bernard Hirschel Luc Perrin Milos Opravil Markus Flepp Jan von Overbeck Michel P. Glauser Silvia Ghezzi Elisa Vicenzi Guido Poli Adriano Lazzarin 《European journal of immunology》1997,27(12):3223-3227
Homozygous (Δccr5/Δccr5) and heterozygous (CCR5/Δccr5) deletions in the β-chemokine receptor 5 (CCR5) gene, which encodes for the major co-receptor for macrophage-tropic HIV-1 entry, have been implicated in resistance to HIV infection and in protection against disease progression, respectively. The CCR5/Δccr5 genotype was found more frequently in long-term nonprogressors (LTNP) (31.0%) than in progressors (10.6%, p < 0.0001), in agreement with previous studies. Kaplan-Meier survival analyses showed that a slower progression of disease, i.e. higher proportion of subjects with CD4+ T cell counts >500/μl (p = 0.0006) and a trend toward a slower progression to AIDS (p = 0.077), was associated with the CCR5/Δccr5 genotype. However, when LTNP were analyzed separetely, no significant differences in CD4+ T cell counts (p = 0.12) and viremia levels (p = 0.65) were observed between the wild-type (69 % of LTNP) and the heterozygous (31.0 %) genotypes. Therefore, there are other factors which play a major role in determining the status of nonprogression in the majority of LTNP. Furthermore, there was no evidence that the CCR5/Δccr5 genotype was associated with different rates of disease progression in the group of progressors. Taken together, these results indicate that the CCR5/Δccr5 genotype is neither essential nor sufficient for protection against the progression of HIV disease. 相似文献
97.
Gastrointestinal zygomycosis caused by Mucor indicus in a patient with acute traumatic brain injury.
Maria Deja Steffen Wolf Steffen Weber-Carstens Thomas-Nicolas Lehmann Andreas Adler Markus Ruhnke Kathrin Tintelnot 《Medical mycology》2006,44(7):683-687
We report a gastrointestinal infection caused by Mucor indicus in a patient with severe head injuries. Monotherapy with high-dose liposomal amphotericin B successfully eradicated the mucormycosis. Nevertheless, subsequently a hemicolectomy was necessary due to recurrent bleeding from a deep ulcer. Mucor indicus is an uncommon fungal pathogen, typically found in starters used for food fermentation. Reviewing other reports on Mucor indicus infections, primary gastrointestinal manifestations seem to be typical and indicate an oral route of infection. 相似文献
98.
Comparison of antibody repertoires against Staphylococcus aureus in healthy individuals and in acutely infected patients 总被引:1,自引:0,他引:1
Dryla A Prustomersky S Gelbmann D Hanner M Bettinger E Kocsis B Kustos T Henics T Meinke A Nagy E 《Clinical and diagnostic laboratory immunology》2005,12(3):387-398
The management of staphylococcal diseases is increasingly difficult with present medical approaches. Preventive and therapeutic vaccination is considered to be a promising alternative; however, little is known about immune correlates of protection and disease susceptibility. To better understand the immune recognition of Staphylococcus aureus by the human host, we studied the antistaphylococcal humoral responses in healthy people in comparison to those of patients with invasive diseases. In a series of enzyme-linked immunosorbent assay analyses performed using 19 recombinant staphylococcal cell surface and secreted proteins, we measured a wide range of antibody levels, finding a pronounced heterogeneity among individuals in both donor groups. The analysis revealed marked differences in the antibody repertoires of healthy individuals with or without S. aureus carriage, as well as in those of patients in the acute phase of infection. Most importantly, we identified antigenic proteins for which specific antibodies were missing or underrepresented in infected patients. In contrast to the well-described transient nature of disease-induced antistaphylococcal immune response, it was demonstrated that high-titer antistaphylococcal antibodies are stable for years in healthy individuals. In addition, we provide evidence obtained on the basis of opsonophagocytic and neutralizing activity in vitro assays that circulating antistaphylococcal serum antibodies in healthy donors are functional. In light of these data we suggest that proper serological analysis comparing the preexisting antibody repertoires of hospitalized patients with different outcomes for nosocomial staphylococcal infections could be extremely useful for the evaluation of candidate vaccine antigens in addition to protection data generated with animal models. 相似文献
99.
The aim of the double-blind, placebo-controlled study was to investigate the effects of a continuous combined estrogen-progestogen treatment (Climodien, Lafamme) as compared with estrogen alone on vigilance in insomniac postmenopausal syndrome patients, objectified by EEG mapping. METHODS: In a 3-arm, 2-month parallel group design phase, patients received a combination of estradiol valerate 2 mg and the novel progestogen dienogest 3 mg (Climodien 2/3) or estradiol valerate 2 mg alone or placebo. In a subsequent open-label phase, all patients received estradiol valerate 2 mg+dienogest 2 mg (Climodien 2/2). EEG mapping was carried out before and after the 2-month double-blind phase as well as after the 2-month open-label treatment. RESULTS: As compared with placebo, Climodien 2/3 induced a marked and highly significant increase in absolute power in all frequency bands, specifically in alpha-2 activity. Moreover, a significant increase in relative alpha-2 power, a decrease in relative delta and beta power as well as an acceleration of the dominant frequency and of the delta and alpha centroids suggested a marked improvement in vigilance. In contrast, under estradiol valerate 2 mg alone, only a slight augmentation of alpha and attenuation of relative delta and beta power occurred, suggesting only a slight vigilance improvement as compared with placebo. Thus, dienogest 2 mg increased the estrogen effect, which was also confirmed by a statistical evaluation of the differences between Climodien 2/3 and estradiol valerate alone (augmentation of alpha-2, attenuation of relative beta, acceleration of the dominant frequency). Moreover, Climodien 2/2 also markedly increased alpha-2 power, decreased relative beta-2 power and accelerated the alpha centroid. Finally, comparing Climodien 2/3 with Climodien 2/2, there was even a dose-efficacy relation. CONCLUSIONS: Estradiol valerate 2 mg improves vigilance slightly, thereby confirming previous findings. The additional administration of dienogest does not minimize the effect of estrogen, but on the contrary increases it, which makes the combination superior to both placebo and estradiol valerate alone. Vigilance improvement may be of great therapeutic benefit to menopausal syndrome patients at a time when increased adaptability is needed to adjust to increasing sexual, marital, occupational and social difficulties known to occur specifically in this period of life. 相似文献
100.
Papadimitriou GN Dikeos DG Souery D Del-Favero J Massat I Avramopoulos D Blairy S Cichon S Ivezic S Kaneva R Karadima G Lilli R Milanova V Nöthen M Oruc L Rietschel M Serretti A Van Broeckhoven C Stefanis CN Mendlewicz J 《Psychiatric genetics》2003,13(4):211-220
The co-segregation in one pedigree of bipolar affective disorder with Darier's disease whose gene is on chromosome 12q23-q24.1, and findings from linkage and association studies with the neighbouring gene of phospholipase A2 (PLA2) indicate that PLA2 may be considered as a candidate gene for affective disorders. All relevant genetic association studies, however, were conducted on bipolar patients. In the present study, the possible association between the PLA2 gene and unipolar affective disorder was examined on 321 unipolar patients and 604 controls (all personally interviewed), recruited from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, and Italy) participating in the European Collaborative Project on Affective Disorders. After controlling for population group and gender, one of the eight alleles of the investigated marker (allele 7) was found to be more frequent among unipolar patients with more than three major depressive episodes than among controls (P<0.01); genotypic association was also observed, under the dominant model of genetic transmission (P<0.02). In addition, presence of allele 7 was correlated with a higher frequency of depressive episodes (P<0.02). These findings suggest that structural variations at the PLA2 gene or the chromosomal region around it may confer susceptibility for unipolar affective disorder. 相似文献