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Ohne ZusammenfassungHerrn ProfessorTeutschlaender bin ich für seine Hilfe sehr zu Dank verpflichtet.Nach Drucklegung dieser Arbeit ging mir ein Bericht von Herrn Dr.te Hennepe, Rotterdam, zu: Some Duck Diseases aus The Utility Duck Club Year Book. Es ist bemerkenswert, daß dieser gute Kenner der Hansgeflügelerkrankungen bei seinen so zahlreichen Entenuntersuchungen — jährlich gegen 200 — nur eine einzige Geschwulstbeobachtung erwähnt. Genauere Angaben hierüber fehlen.  相似文献   
33.
Objective. To assess the prevalence, clinical manifestations, associated genital infections, and HLA associations of reactive arthritis (ReA) among patients attending an urban sexually transmitted diseases (STD) clinic. Methods. Using a standardized questionnaire, 271 consecutive adults, primarily black, with possible or proven Chlamydia trachomatis genital infection were screened for symptoms of ReA. A followup questionnaire was administered 6 weeks later by mail. Patients who reported at least 1 symptom were evaluated by a rheumatologist. HLA–B typing was performed on patients with objective ReA features. Results. Nine of 217 patients (4.1%) with genital infection/inflammation had objective ReA features. Chlamydial or nongonococcal STD syndromes were diagnosed in 8 of these 9 patients (88%). Genital infection/inflammation was asymptomatic in 78% of patients with ReA features. HLA–B27 or other B7–cross-reactive group antigens were not associated with the occurrence of ReA. Conclusion. Nongonococcal genital infections, often asymptomatic, can trigger a relatively mild ReA in a larger number of exposed patients than previously thought, irrespective of the individual's HLA status.  相似文献   
34.
The successful therapy of enterococcal endocarditis requires prolonged administration of synergistic antibiotic combinations. Controversy has arisen regarding optimal therapy (i) when the organism possesses high-level streptomycin resistance, and (ii) when the patient is allergic to penicillin. This study examines these questions in vitro and in a rabbit model of enterococcal endocarditis. The combination of penicillin with either streptomycin or gentamicin increased the rate of bacterial killing in vitro and in vivo when compared with penicillin alone (P < 0.05) when the test strain was relatively susceptible to streptomycin (minimal inhibitory concentration, 128 mug/ml). Only the combination of penicillin and gentamicin was consistently more effective than penicillin alone (P < 0.01) when the test strain was highly resistant to streptomycin (minimal inhibitory concentration > 150,000 mug/ml). The combination of vancomycin and streptomycin was more rapidly bactericidal than vancomycin alone in vitro and in the animal model against the streptomycin-susceptible strain (P < 0.01). The relative rate of in vitro bacterial killing by various antibiotics and combinations was predictive of the efficacy of these drugs in eradicating enterococci from cardiac vegetation in experimental endocarditis.  相似文献   
35.
The toxicity of mRNA-lipid nanoparticle (LNP) vaccines depends on the total mRNA-LNP dose. We established that the maximum tolerated dose of our trivalent mRNA-LNP genital herpes vaccine was 10 μg/immunization in mice. We then evaluated one of the mRNAs, gD2 mRNA-LNP, to determine how much of the 10 μg total dose to assign to this immunogen. We immunized mice with 0.3, 1.0, 3.0, or 10 μg of gD2 mRNA-LNP and measured serum IgG ELISA, neutralizing antibodies, and antibodies to six crucial gD2 epitopes involved in virus entry and spread. Antibodies to crucial gD2 epitopes peaked at 1 μg, while ELISA and neutralizing titers continued to increase at higher doses. The epitope results suggested no immunologic benefit above 1 μg of gD2 mRNA-LNP, while ELISA and neutralizing titers indicated higher doses may be useful. We challenged the gD2 mRNA-immunized mice intravaginally with HSV-2. The 1-μg dose provided total protection, confirming the epitope studies, and supported assigning less than one-third of the trivalent vaccine maximum dose of 10 μg to gD2 mRNA-LNP. Epitope mapping as performed in mice can also be accomplished in phase 1 human trials to help select the optimum dose of each immunogen in a multivalent vaccine.  相似文献   
36.
During a 15-week period, six full-time faculty members supervised the replacement of amalgam restorations by clinical dental students. The tooth numbers, the amalgam surfaces replaced, the reasons for replacement, and the instructors were compared. The students removed 956 surfaces of amalgam from 436 teeth. The primary reasons cited for replacement were marginal breakdown (69%) and caries (33%).  相似文献   
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Multilamellated structures (MS), which accumulate in the lungs of patients with pulmonary alveolar proteinosis, were examined under the electron microscope. MS, in general, consisted of alternating light and dark lamellae arranged concentrically about membranous vesicles or electron-dense bodies. The darker osmiophilic lamellae consisted of trilaminar membranes 80 to 100 A thick, and the lighter lamellae, which varied from 150 to 300 A in width, appeared amorphous. MS made up 42.6 +/- 12.4% (n = 4) of the total particulate volume present in the pulmonary lavage effluents. MS resembled tubular myelin structures from the lungs of patients, although these latter structures accounted for only 1.6 +/- 2.3% (n = 4) of the total particulate volume. Abnormalities, such as polygonal tubules, irregular tubule dimensions, and large size potential, indicated that tubular myelin structures in the lungs of patients were variable in structure. MS appear to be a form of tubular myelin structure. MS were treated with a variety of disruptive agents and then examined under the electron microscope. Information was obtained about the composition of the MS and the intermolecular forces involved in their three-dimensional organization. Extraction of the MS with acetone or treatment of the structures with phospholipase c resulted in loss of membranes from the structures without a concomitant loss of the intermembranous amorphous material, indicating that phospholipids were a major membrane component. Analysis of phospholipids in the acetone extracts of the MS revealed that the membranes consisted of 45% phosphatidylcholine and that the major fatty acid of the phosphatidylcholine was palmitate (76%). The amorphous material of the intermembranous spaces consisted primarily of protein, since it was destroyed by the proteases trypsin and pronase without loss of the membranes. Reducing agents such as mercaptoethanol and dithiothreitol were disruptive, indicating the importance of disulfide bridges between the protein constituents in maintaining the integrity of the MS. The significance of hydrophobic interactions between the protein constituents was demonstrated by the disruptive action of chaotropic agents according to the sequence KSCN greater than KI greater than KCl. These data indicate that MS consist of phospholipid membranes organized in a protein matrix maintained by intermolecular disulfide bridges and hydrophobic interactions.  相似文献   
39.
Digene's Hybrid Capture 2 (HC2) CT/GC, CT-ID, and GC-ID DNA tests were evaluated by comparison to traditional culture methods for detecting Chlamydia trachomatis and Neisseria gonorrhoeae infections in 669 cervical specimens from high-risk female populations attending two sexually transmitted disease clinics. For detection of either or both infections, the HC2 CT/GC test algorithm had 93.8% sensitivity and 95.9% specificity compared to those of culture. After resolution of discrepant results by direct fluorescent-antibody (DFA) staining or PCR assay, the relative sensitivity and specificity of the HC2 CT/GC test algorithm increased to 94.8 and 99.8%, while the values for culture were 83.6% (McNemar's P value, 0.0062) and 100%, respectively. For detection of the individual pathogens, the relative sensitivities for the HC2 CT-ID and GC-ID tests were 97.2 and 92.2% and the specificities were greater than 99% compared to culture adjucated by DFA staining and PCR. Test performance varied at the two clinics: the HC2 CT/GC algorithm, CT-ID, and GC-ID tests had significantly higher sensitivities (McNemar's P value, <0.05) than that of culture for the population at one clinic as well as for the combined populations. At the other clinic, the HC2 tests performed as well as culture.  相似文献   
40.
The performance of nucleic acid amplified tests (NAAT) for Chlamydia trachomatis at the cervix and in urine was examined in 3,551 women, and the impacts of clinical findings (age, endocervical and urethral inflammation, menses, and gonococcal coinfection) were assessed. Ligase chain reaction (LCR) and first-generation uniplex PCR were studied relative to an unamplified DNA probe (PACE2) and to an expanded, independent diagnostic reference standard. Relative to the expanded standard, cervical or urine LCR was generally the most sensitive test in most subgroups. Increased detection by NAAT of cervical C. trachomatis over PACE2 was highest among women without mucopurulent endocervical discharge versus those with (relative increase in positivity with cervical LCR, 46%) and among women > or =20 years old versus younger women (relative increase in positivity with cervical LCR, 45%). The sensitivity of cervical PCR was highest when mucopurulent endocervical discharge was present (84%) and highest for cervical LCR when cervical gonococcal coinfection was detected (91%). Urethral inflammation was associated with higher sensitivities of urine LCR (86 compared to 70% when inflammation was absent) and PCR (82 compared to 62% when inflammation was absent). Menses had no effect on test performance. The effects of patient characteristics on test specificities were less pronounced and were closely related to observed sensitivities. These findings support expanded use of NAAT for screening and diagnosis of C. trachomatis in diverse clinical populations of women.  相似文献   
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