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71.
The aim of this study is to compare the rates of clinically relevant and clinically irrelevant neuronal autoantibodies among patients presenting with new neurological symptoms. We reviewed 401 neurological patients who were tested for the Mayo-Clinic paraneoplastic panel from January 2014 to December 2014 at the Johns Hopkins Hospital. We divided antibody-positive patients into two groups: clinically relevant (CR), in which a recognizable autoimmune or paraneoplastic syndrome was confirmed, and clinically irrelevant (CI), in which an autoimmune/paraneoplastic etiology was initially suspected but an alternative diagnosis was eventually found. We used Fisher’s exact test for categorical variables and Mann–Whitney U test for continuous variables to identify differences between the two groups. Fifty-three patients tested positive for one or more neuronal autoantibodies. There were 17 CR (65% females, mean age 56 years), 33 CI, and 3 indeterminate patients. Compared to CI patients, CR patients were more likely to present with movement disorders or stiff person syndrome, have inflammatory CSF markers, cancer or smoking history, concomitant hyponatremia, and classical onconeuronal antibodies. CI patients were more likely to have a neuromuscular presentation, a chronic course, and antibodies against synaptic antigens. By combining the most robust differentiating factors, we developed a simple scale that predicted clinical relevance with an odds ratio of 50.3 (CI 8.2–309.9, P < 0.0001) if the score was ≥ 2. Up to 62% of neuronal autoantibody-positive patients are ultimately found to have an alternative diagnosis. Several clinical and laboratory factors can differentiate CR from CI patients to aid in interpretation of positive results.  相似文献   
72.
To evaluate the sensitivity and specificity of diagnosing Pneumocystis carinii pneumonia (PCP) by Papanicolaou-stained bronchial brushing and wash/lavage specimens obtained by fiberoptic bronchoscopy, the cytologic preparations and clinical records from 58 immunocompromised patients were reviewed. Bronchial brushings and wash/lavage specimens were examined using methenamine silver (Grocott) and Papanicolaou stains. Pneumocystis carinii pneumonia was recognized with Papanicolaou stain by identifying distinctive alveolar casts, which frequently contained collections of encysted sporozoites. Thirty cases of PCP were identified, and Grocott-stained bronchial wash/lavage specimens were positive in 29 instances (97%). Grocott staining of the transbronchial biopsy was positive for PCP in 18 of 22 specimens (82%). Bronchial brushings were insensitive, yielding a positive specimen in only 30% of cases of PCP. Alveolar casts of PCP were identified by Papanicolaou-stained slides of wash/lavage specimens in 83% of cases of Pneumocystis pneumonia. These proteinaceous alveolar casts were not seen in other pulmonary disorders. Encysted sporozoites were found in 56% of cases in which Papanicolaou-stained alveolar casts were identified. We conclude that the diagnosis of PCP can be made rapidly and reliably on the Papanicolaou-stained bronchial wash/lavage or bronchial brush specimens by detecting the characteristic alveolar casts, which contain P. carinii-encysted sporozoites. The presence of encysted sporozoites within alveolar casts is pathognomonic for PCP, and methenamine silver stains can be eliminated in those cases in which encysted sporozoites are identified.  相似文献   
73.
Aronchick  JM; Rossman  MD; Miller  WT 《Radiology》1987,163(3):677-682
Patients with suspected chronic beryllium disease underwent bronchoscopy and bronchoalveolar lavage. Their bronchoalveolar lymphocytes were incubated with beryllium salts, and quantitative lymphocyte transformation was measured. Seventeen patients with a positive lymphocyte proliferation test were evaluated radiographically with the International Labour Office classification. The most common radiographic abnormalities included diffuse small round and reticular opacities. Hilar adenopathy, linear scars, lung distortion, bullae, and pleural thickening were found less commonly. Specific radiographic findings were compared with pulmonary function abnormalities. The extent of radiographic profusion of small opacities and the presence of linear scars did not correlate with pulmonary function abnormalities. There was, however, a significant correlation between extensive pleural disease and reduced vital capacity in this small group of patients.  相似文献   
74.
A bstract Background and aim of the study : Cardiomyoplasty (CMP) has been proposed as a treatment for pediatric patients, but restriction of cardiac growth by the muscle wrap is a potential source of concern. This possibility was investigated in an immature animal model. Methods : Six-week-old rats (body weight 203.8 ± 5.4 g, mean ± SEM) underwent either left thoracotomy with CMP (group I, n = 7), or thoracotomy without CMP (group II, n = 8). A third group (group III, n = 7) served as untreated controls. Final measurements were made 20 weeks later after body weights had reached a plateau. Results : Preoperative body weights were not significantly different between the groups. At elective sacrifice, the body weights of animals that underwent surgery did not differ significantly (group I, 558.0 ± 21.5 g and group II, 617.3 ± 20.3 g), but were significantly less than those of control animals (727.6 ± 13.3 g, p < 0.001 and p < 0.01, respectively). Cardiac ventricular weights in the CMP group were significantly less than those of control animals (group I, 1.21 ± 0.06 g; group III 1.45 ± 0.04 g; p < 0.01), but were not statistically different from those of the sham thoracotomy group (group II, 1.36 ± 0.05 g). Mean left ventricular end-diastolic volumes were similar in all groups (group I, 0.67 ± 0.07 mL; group II, 0.66 ± 0.07 mL; and group III, 0.69 ± 0.10 mL; p = ns). Conclusions : A major surgical procedure impairs growth in juvenile rats. No evidence emerged from this study for additional restriction of cardiac development due to cardiac wrapping. However, studies that include stimulated muscle wraps are needed before CMP should be considered for the pediatric age group.  相似文献   
75.
Dual-action cephalosporins: cephalosporin 3'-quinolone carbamates   总被引:1,自引:0,他引:1  
A series of cephalosporins has been prepared in which the 3'-position was linked to the nitrogen of the antibacterial quinolone ciprofloxacin through a carbamate function. Like the ester-linked and quaternary-linked dual-action cephalosporins reported earlier, these carbamate-linked compounds exhibited a broad antibacterial spectrum derived from both cephalosporin-like and quinolone-like activities, suggesting a dual mode of action. Studies to elucidate details of the mechanism of action have been inconclusive. Ciprofloxacin liberated as a consequence of bacterial enzyme-mediated reactions may contribute to the second mode of action, although some evidence indicates that the intact carbamate-linked bifunctional molecules may possess intrinsically both beta-lactam and quinolone activities.  相似文献   
76.
Nickel is an established human and animal carcinogen, but efforts to demonstrate its mutagenicity in a number of cell types have not been successful. In this report we describe the mutational response to nickel compounds in the G12 cell line, an hprt deficient V79 cell line containing a single copy of the E. coli gpt gene. This cell line has a low spontaneous background, making it suitable for assessment of mutagenic responses to environmental contaminants. When G12 cells were treated with insoluble particles of crystalline nickel sulfide < 5 μm in diameter, a strong, dose-dependent mutagenic response was observed up to 80 times the spontaneous background. Of 48 mutant gpt(?) clones isolated that were induced by insoluble nickel, all were capable of DNA amplification of the gpt sequences by polymerase chain reaction (PCR). The ability to produce full-length PCR products is an indication that large deletions of gene sequences have not occurred. When G12 cells were treated with soluble nickel sulfate, the mutational response was not significantly increased over the spontaneous background. This difference in mutagenic response reflects a large difference in the mutagenic potential of soluble and insoluble nickel compounds, which reflects the carcinogenic potential of these forms of nickel. © 1993 Wiley-Liss, Inc.  相似文献   
77.
78.
OBJECTIVE: The Antiretroviral Treatment Access Study-II (ARTAS-II) evaluated a brief case management intervention delivered in health departments and community-based organizations (CBOs) to link recently diagnosed HIV-infected persons to medical care rapidly. METHODS: Recently diagnosed HIV-infected persons were recruited from 10 study sites across the United States during 2005 to 2006. The intervention consisted of up to 5 sessions with an ARTAS linkage case manager over a 90-day period. The outcome measure was whether or not the participant had seen an HIV medical care provider at least once within 6 months of enrollment. Multivariate logistic regression was used to identify significant predictors of receiving HIV medical care. RESULTS: Seventy-nine percent (497 of 626) of participants visited an HIV clinician at least once within the first 6 months. Participants who were older than 25 years of age, Hispanic, and stably housed; had not recently used noninjection drugs; had attended 2 or more sessions with the case manager; and were recruited at a study site that had HIV medical care colocated on its premises were all significantly more likely to have received HIV care. CONCLUSIONS: The ARTAS linkage case management intervention provides a model that health departments and CBOs can use to ensure that recently diagnosed HIV-infected persons attend an initial HIV care encounter.  相似文献   
79.

Objective

To investigate the immunological effect of Vernonia amygdalina (V. amygdalina) leaf extract and immunace® on HIV infected patients taking highly active antiretroviral therapy.

Methods

Fresh V. amygdalina leaves were collected within Nsukka area in Enugu State. The leaves were rinsed with distilled water. Two handful of cleaned fresh leaves were soaked in 200 mL water and squeezed gently by hand to a mixture. Clients were divided into four groups and each group was given different combination. They took the medication for four weeks. The immune effect was tested against marketed immune booster in some retroviral clients.

Results

The mean absolute CD4 count was increased in the client who took the extract or supplement. And the clients who took both the extract and supplement had a greater increase in the CD4 count. The increased CD4 was significant as compared with the control group (P<0.05). The skin rashes were also improved in the entire groups.

Conclusions

It can be concluded that the aqueous extract of V. amygdalina and immunace or both have immunological effect on HIV infected patients. Therefore, we suggest that the V. amygdalina extract or immunace or both could be used as adjuvant in the management of HIV/AIDS clients.  相似文献   
80.
Escherichia coli O157:H7, Salmonella, and Listeria are foodborne pathogens of critical importance that often colonize cattle. E. coli O157:H7 can be specifically killed by lytic bacteriophage, and lytic bacteriophage treatment has been suggested as a pre-harvest intervention strategy to reduce foodborne pathogens in cattle. To date, no systematic approach to determine the incidence of E. coli O157:H7-infecting lytic bacteriophage has been published. Therefore, the current study was designed to determine (1) the incidence of E. coli O157, Salmonella spp., and Listeria and (2) the incidence of E. coli O157:H7-infecting bacteriophage in the feces of feedlot steers in commercial feedlots in the United States. Fecal samples (n=60) were collected from four feedlots in two Southern Great Plains states (total (n=240 fecal samples). Salmonella and E. coli O157:H7 were found in 3.8% and 11.7% of the fecal samples, respectively. Bacteriophage targeting E. coli O157:H7 were found in all four feedlots, in 15% of the individual fecal samples, and in 55% of the cattle pens. Our results indicate that such bacteriophage are widespread in feedlot cattle, suggesting that further research into the ecological role of bacteriophage in the gastrointestinal tract is needed.  相似文献   
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