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51.
We isolated bacteria from ticks, lice and fleas. Partial small subunit rRNA sequences were obtained for each isolate and the closest matches in the FastA database were determined. These bacteria were mostly Gram-positive (Firmicutes), although representatives from the Proteobacteria (alpha, beta, gamma subdivisions) and CFB group were also isolated. Most of the isolates we found were from genera that were present in most of the ectoparasites studied, but a few genera were restricted to one species of ectoparasite. The most commonly isolated genera were Stenotrophomonas, Staphylococcus, Pseudomonas, Acinetobacter and Bacillus. Species of Bacillus and Proteus, which have biopesticide potential, were found in some of these ectoparasites. Overall, the communities of bacteria were similar to those found in other studies of parasitic arthropods. 相似文献
52.
Staphylococcal toxin-induced T cell proliferation in atopic eczema correlates with increased use of superantigen-reactive Vbeta-chains in cutaneous lymphocyte-associated antigen (CLA)-positive lymphocytes 总被引:2,自引:0,他引:2 下载免费PDF全文
Staphylococcal superantigens have been implicated in the pathogenesis of atopic dermatitis (AD). This may occur through superantigenic activation of T lymphocytes and their subsequent induction of the skin homing receptor CLA on activated cells. We investigated the proliferative responses of peripheral blood mononuclear cells (PBMC) from 10 patients with an infective exacerbation of AD and six normal controls to the staphylococcal superantigens, staphylococcal enterotoxin A and B (SEA, SEB) and toxic shock syndrome toxin-1 (TSST-1), and the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A). We also assessed CLA and T cell receptor (TCR) Vbeta-chain expression by immunofluorescence and flow cytometry before and after stimulation. PBMC from AD patients showed two-fold increased proliferation to SEA and SEB (P < 0.01) compared with normals, whereas the response to mitogenic stimulation was identical. Analysis of (TCR) Vbeta-chain expression demonstrated increased use of superantigen-reactive Vbeta families in freshly isolated PBMC in AD patients compared with controls. This pattern of Vbeta-chain expression was only observed in the CLA+ but not the total population of T cells. Furthermore, there was a positive correlation between the enhanced PBMC proliferative response and increased expression of superantigen-reactive Vbeta families in atopic patients. These data support the concept that superantigens are important in the pathogenesis of this common condition, and also provide evidence that the increased use of certain Vbeta families in circulating, CLA+, skin homing lymphocytes is of functional significance. 相似文献
53.
54.
The possibility of interfering with the normal function of tick hemolymph using antihemolymph antibodies taken in with the bloodmeal, was investigated. Cell free hemolymph from repleteAmblyomma americanum andDermacentor variabilis ticks was used to immunize rabbits. Immunized rabbits developed high antihemolymph antibody titers (ca. 105) and had no ill side effects. Rabbits were simultaneously infested with larvae, nymphs, and adult ticks. The biological performance of ticks fed on immunized rabbits was virtually identical to that of ticks fed on nonimmunized rabbits. Usually, the mean engorgement weights of nymphs and females and the weights of the egg masses of both species were slightly higher for ticks fed on the nonimmunized rabbits but differences were not significant (P>0.05) due to a large standard deviation. The possibility of deactivating a single hemolymph component with specific antibodies is discussed.Journal article 4979 of the Agricultural Experiment Station, Oklahoma State University, Stillwater, OK, USA 相似文献
55.
Zusammenfassung Atemphysiologische Untersuchungen an 19 Patienten mit Ventilationsstörungen der Lunge mit dem Atmungsanalepticum Micoren ergeben eine Ventilationssteigerung um 60% des Ausgangswertes, eine Abnahme der arteriellen CO2-Spannung und eine Zunahme des Blut-pH, somit eine ventilationsbedingte Verschiebung der Blutgase in Richtung einer relativen respiratorischen Alkalose. Im Mittelpunkt der Untersuchung steht die Frage einer über die Atmungserregung hinaus bei der respiratorischen Acidose und Atemdepression erzielbaren Erregbarkeitsänderung der Zentren. Im Gegensatz zu Patienten ohne respiratorische Acidose läßt sich bei Kranken mit respiratorischer Acidose eine Steigerung der Erregbarkeit auf CO2-Reiz und eine wahrscheinlich begrenzte Verzögerung der unter O2-Atmung drohenden zentralen Depression nachweisen. Indikationen und klinische Gesichtspunkte einer medikamentösen Atmungserregung werden unter besonderer Berücksichtigung der respiratorischen Acidose besprochen.Mit freundlicher Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
56.
I. Foo A. J. R. Macfarlane D. Srivastava A. Bhaskar H. Barker R. Knaggs N. Eipe A. F. Smith 《Anaesthesia》2021,76(2):238-250
Intravenous lidocaine is used widely for its effect on postoperative pain and recovery but it can be, and has been, fatal when used inappropriately and incorrectly. The risk-benefit ratio of i.v. lidocaine varies with type of surgery and with patient factors such as comorbidity (including pre-existing chronic pain). This consensus statement aims to address three questions. First, does i.v. lidocaine effectively reduce postoperative pain and facilitate recovery? Second, is i.v. lidocaine safe? Third, does the fact that i.v. lidocaine is not licensed for this indication affect its use? We suggest that i.v. lidocaine should be regarded as a ‘high-risk’ medicine. Individual anaesthetists may feel that, in selected patients, i.v. lidocaine may be beneficial as part of a multimodal peri-operative pain management strategy. This approach should be approved by hospital medication governance systems, and the individual clinical decision should be made with properly informed consent from the patient concerned. If i.v. lidocaine is used, we recommend an initial dose of no more than 1.5 mg.kg-1, calculated using the patient’s ideal body weight and given as an infusion over 10 min. Thereafter, an infusion of no more than 1.5 mg.kg-1.h-1 for no longer than 24 h is recommended, subject to review and re-assessment. Intravenous lidocaine should not be used at the same time as, or within the period of action of, other local anaesthetic interventions. This includes not starting i.v. lidocaine within 4 h after any nerve block, and not performing any nerve block until 4 h after discontinuing an i.v. lidocaine infusion. 相似文献
57.
Clinical aspects of vasospasm 总被引:1,自引:0,他引:1
In summary, clinically significant vasospasm is characterized by several relatively consistent features. Those patients most at risk are adults, of either sex, who have had a subarachnoid hemorrhage about 4 to 9 days previously; who had a poor clinical grade on admission; and in whom a CT scan taken 24 to 48 hours after the ictus showed a thick layer of blood surrounding one or more of the major cerebral vessels. Initially afebrile, affected patients later develop a steady low-grade fever and may have an elevated WBC count, but no infectious source of fever can be found. Patients complain of worsening headache, but not as bad as the one a few days ago; the neck may feel a little more stiff. The pulse is slightly faster than usual, the blood pressure perhaps a bit higher; however, the ECG shows only "cerebral T waves." An antifibrinolytic agent may have been used. The serum sodium concentration has dropped significantly. Such patients need a more thorough examination than usual, directed toward more subtle neurologic signs, and a few extra checks during the day by both physician and nurses, so that we can apply what remedies we have when the patients are just "a little more confused," rather than later, when they are exhibiting decerebrate posturing and coma. 相似文献
58.
Most HIV/AIDS behavior research involving African American women has focused on traditional high risk populations, such as those in drug treatment centers, STD clinics, and hospitals. Few studies have examined the health needs and behaviors of African American women in the general population (i.e., working mothers and homemakers). The Parent Health Project examined beliefs and concepts of illness, including AIDS, of low income African American mothers of young children. We used a variety of methods of community outreach and recruitment strategies to gain access and trust from these African American women, including (1) recruitment of women who had children in a related research project, (2) subject reimbursement, and (3) culturally sensitive community based outreach. Of approximately 200 women contacted, 147 (74%) agreed to participate in a two-hour face-to-face interview about concepts of health and illness. Through our efforts, we were able to gain access to a population generally not studies in HIV/AIDS research. We were also exposed to a number of issues, concerns and behaviors faced by women not classified as high risk, yet who are at risk as a result of their own and/or their sexual partner's(s) risk behaviors. 相似文献
59.
We describe the epidemiology of human rabies postexposure prophylaxis (PEP) in four upstate New York counties during the 1st and 2nd year of a raccoon rabies epizootic. We obtained data from records of 1,173 persons whose rabies PEP was reported to local health departments in 1993 and 1994. Mean annual PEP incidence rates were highest in rural counties, in summer, and in patients 10 to 14 and 35 to 44 years of age. PEP given after bites was primarily associated with unvaccinated dogs and cats, but most (70%) was not attributable to bites. Although pet vaccination and stray animal control, which target direct exposure, remain the cornerstones of human rabies prevention, the risk for rabies by the nonbite route (e. g., raccoon saliva on pet dogs' and cats' fur) should also be considered. 相似文献
60.
Barker BF 《Seminars in diagnostic pathology》1999,16(4):297-301
The odontogenic myxoma is an uncommon tumor that has the potential for extensive bony destruction, extension into surrounding structures, and a relatively high recurrence rate. Treatment often requires bone resection. The bland histologic features of a monotonous proliferation of a loose, mesenchymal fibrous tissue that lacks atypia may easily lead to a misdiagnosis. The primitive dental pulp, the dental papilla, and the tooth follicle are histologically similar to myxoma. These soft tissue fragments often separate from extracted developing teeth that are submitted to the pathologist and may easily be misinterpreted as an odontogenic myxoma. The pathologist must have good clinical and radiographic correlation to avoid a misdiagnosis and to prevent unnecessary additional surgery. 相似文献