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41.
Environmental control in managing patients with immunodeficiency ranges from the exceedingly complex to the relatively simple. At one end of the spectrum is the total isolation technology applied to David, the "Bubble Boy" who lived his entire life behind sterile plastic barriers. At the other end of the spectrum is the simpler technology applied to patients receiving bone marrow transplants who are maintained in ordinary private hospital rooms and attended by personnel who merely observe handwashing precautions. Most properly performed and controlled studies of the use of special isolation procedures to reduce infections derive from patients receiving bone marrow transplants for conditions of aplastic anemia and leukemia or patients receiving chemotherapy for malignancy. The design of isolation procedures for immunodeficient patients borrows from these studies because of the relatively small number of immunodeficient patients. These studies have shown that laminar airflow rooms produce a significantly lower incidence of infections but may not change the mortality of all patients. Also, protective isolation has clearly reduced the incidence and severity of graft-versus-host disease in transplanted patients with aplastic anemia. Recently there has been a trend away from strict isolation procedures because careful studies have indicated that host rather than acquired pathogens are responsible for at least 85% of infections in these special patients. Also, the human stress of prolonged isolation is becoming increasingly recognized. The complex and expensive isolation techniques that were used in David's case are no longer being utilized in immunodeficient subjects, partly because new transplantation technology has made it possible to cross histocompatibility barriers, obviating the need for permanent isolation. 相似文献
42.
A L Guerra A Rossi L M Paiva H K Sato V A Souza P T Sakane E R Baldacci 《Revista de saúde pública》1999,33(4):374-378
OBJECTIVE: A measles outbreak occurred in S. Paulo state, during 1996 and 1997, resulting in 20,921 cases. Forty seven percent of the cases occurred in people between 20 and 29 years of age, and one of the control strategies of the Department of Health was the vaccination of health care workers. The prevalence of antibodies against measles among the hospital pediatricians was investigated. METHODS: One hundred and fifty samples were taken from volunteer pediatricians to test for measles antibodies using ELISA. A questionnaire about their having had measles and the vaccine was filled out. RESULTS: Of the 150 doctors, 122 (81.4%) were female and 28 (18.6%) male, of between 23 and 46 years of age (mean and median 27 years). The majority (98%-147/150) had protective levels of antibodies against measles (>100 UI/ml); 118 (80.3%-118/147) without and 29 (19.7%-29/147) with a history of measles. Only 3 pediatricians (2%-3/150), had negative serology, 2 without and 1 with a history of measles. Out of the 118 without history of measles, 79 (67%-39/118) in spite of the protective level of antibodies against measles, did not know if they, had been vaccinated. Out of the 79 vaccinated pediatricians, 64 (81%-64/79), had been vaccinated 25 years before, and still maintained protective levels of antibodies. Of the 3 doctors with negative serologies only one declared that he had been vaccinated. CONCLUSIONS: Measles seroprevalence among pediatricians of this hospital is high, especially due to preceding vaccination. On the other hand, the 2% of pediatricians with negative serology, in an epidemic situation could constitute a significant population for the acquisition and dissemination of the disease. 相似文献
43.
Lapachol is a naphtoquinone with therapeutic potential against Chagas disease and is also used as an antimalarial agent. To study the reproductive toxicity potential of Lapachol, pregnant Wistar rats were treated with 0.5 mL of distilled water (control group), 0.5 mL of hydroalcoholic solution (vehicle group), or 20 mg of Lapachol in 0.5 mL of hydroalcoholic solution (treated group) by oral gavage from the 8th to the 12th day of pregnancy. The following variables were observed: maternal body weight on days 1, 6, 15, and 21; food intake on days 2, 6, 15, and 21 of pregnancy. The number of live and dead fetuses and the sites of resorptions were counted. The ovaries were weighed and the corpora lutea were counted. Data were analyzed by ANOVA one-way Dunnett test and chi 2 test. Results showed that mothers were uneffected but there was 100% fetal/embryo mortality, indicative of a strong interceptive effect of Lapachol in rats. 相似文献
44.
Meta-analysis has been little explored to make an overall assessment of linkage from different studies. In practice, it is likely that published linkage studies will only report p-values. We compared the performance of the widely used Fisher method for combining p-values with that of pooling raw data. More loci were consistently found by pooling raw data. In the absence of further information, combining p-values can provide an overall, but limited, assessment of different linkage studies. However, meta-analysis would be better viewed as a preliminary step toward the goal of analyzing the pooled raw data. 相似文献
45.
The adult hip: an anatomic study. Part I: the bony landmarks 总被引:2,自引:0,他引:2
T G Armbuster J Guerra D Resnick T G Goergen M L Feingold G Niwayama L A Danzig 《Radiology》1978,128(1):1-10
A comprehensive anatomic, pathologic and radiographic study of the adult hip was undertaken to define bony landmarks which, when altered, are reliable indicators of disease. Methodology included radiography of cadaveric specimens and analysis of over 300 anteroposterior (AP) radiographs of "normal" adult hips. This information was applied to clinical situations with the following conclusions: (a) The diagnosis of protrusio acetabuli is warranted if the acetabular line projects medial to the ilioischial line by 3 mm or more in men and by 6 mm or more in women. (b) In acetabular trauma, an AP and two oblique radiographs (30 degrees anterior oblique and 30--45 degrees posterior oblique) are required for complete evaluation. (c) Characteristic alterations in the joint space allow accurate diagnosis of disease. 相似文献
46.
F. de Bernardis M. Boccanera L. Rainaldi C. E. Guerra I. Quinti A. Cassone 《European journal of epidemiology》1992,8(3):362-367
Prevalence, serotype and in vitro secretion of aspartyl proteinase, a virulence enzyme, were studied in Candida isolates from the oral cavity of 337 HIV-infected subjects. Controls were 95 age-sex-matched HIV- (seronegative) subjects, belonging to either HIV-risk categories (47) or to the normal, general population (48). Fungi were isolated from 155 HIV+ subjects. C. albicans was the most prevalent species (85.8% of all isolates). 94.6% of C. albicans isolates were serotype A and all were agglutinated by a monoclonal antibody (AF1) directed against a major mannoprotein immunogen of the candidal cell wall, confirming previous results with C. albicans isolates from non-immunodeficient subjects. With regard to the stage of HIV infection, there were no statistically significant differences in the incidence of oral Candida carriage between asymptomatic (stage II) HIV+ and HIV- subjects, and between stage II and lymphadenopathic (stage III) individuals. Also, the low (3.8%) incidence of oral candidiasis in the subjects of the latter stage was insignificant with respect to stage II subjects. However, the incidence of C. albicans in stage IV (AIDS) subjects (46.8%) was significantly higher than in all other subjects, and in almost all cases, fungal isolation was accompanied by oral thrush and lower CD4+ lymphocyte counts (< 400 × 10°/L).All isolates of C. albicans were proteolytic in vitro, as assessed by scoring the proteinase activity on BSA agar and monitoring the secreted proteinase antigen by a highly sensitive (1 ng) and specific immunoenzymatic assay. However, by both methods, the isolates from subjects at stages III and IV of infection produced more secretory proteinase than the isolates from either HIV+ asymptomatic subjects or HIV- controls. The differences could not be attributed to particular culture media or source of Candida isolation (carriage versus active infection). Thus, the isolates of C. albicans from advanced HIV infection are serologically similar but more proteolytic than the isolates from earlier stages of HIV infection or those from HIV-uninfected subjects. The apparently higher virulence of C. albicans from AIDS subjects may represent a co-factor in determining and/or aggravating oral candidiasis in these patients. 相似文献
47.
The midvastus surgical approach in total knee arthroplasty 总被引:2,自引:0,他引:2
We report a study of 2 surgical approaches to the knee in 42 consecutive patients undergoing a total arthroplasty. They were
divided into 2 groups. In Group 1 (n=17) the knee was exposed through classic medial parapatellar arthrotomy and in Group 2 (n=25) the knee was approached through the fibers of the medial vastus. Preoperative assessment did not reveal any statistical
differences between the groups, and blood loss, operation time, biochemistry values and radiographic evaluation were also
similar. However, a higher number of lateral releases, a loss of knee extension and a reduced range of motion were significantly
associated with classical parapatellar arthrotomy. As the number of operative or postoperative complications was not increased,
we recommend the mid-vastus approach for total knee arthroplasty.
Accepted: 3 January 2000 相似文献
Résumé Nous présentons une étude de 42 arthroplasties totales consécutives de genoux qui ont été divisées en deux groupes. Le groupe 1 (n=17) a eu une voie d’abord classique par arthrotomie antéro-interne parapatellaire et le groupe 2 (n=25) a eu un abord à travers les fibres du vastus medialis. Entre les deux groupes, il n’y a pas de différence significative entre les données pré-opératoires, la perte sanguine, le temps opératoire et l’état radiographique. Dans le groupe 1, un plus grand nombre de libérations externes a été nécessaire, une perte de la force d’extension a été notée ainsi qu’une diminution de l’amplitude articulaire. Comme le taux de complications opératoires et postopératoires n’a pas été majoré, nous recommandons ce type d’approche à travers les fibres du vastus medialis pour l’arthroplastie totale de genou.
Accepted: 3 January 2000 相似文献
48.
We report the singular case of an exceptionally large giant communicating artery aneurysm successfully treated with a direct surgical approach. The clinical presentation was a relatively short history of frontal headache. In the pre- and postcontrast CT scans the lesion mimicked an intracranial tumor. At surgery the intraluminal thrombus was partially removed with an ultrasonic surgical aspirator; the decompression allowed the isolation and subsequent temporary dipping of the tracts A1 and A2 of both the anterior cerebral arteries. It was then possible to complete the thrombectomy and to dip the neck of the aneurysm. The report emphasizes the indispensable role of MRI for the accurate diagnosis of giant intracranial aneurysms and the recent improvement of the surgical results concerning this category of aneurysms (mainly related to the present wider availability of technical surgical instrumentation). 相似文献
49.
50.