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61.
Under laboratory conditions, various studies have shown that changes in immunological parameters must be expected after exposure to ultraviolet (UV) light. The objective of the present study was to evaluate, whether such changes can also be revealed after a vacation to a sunny country without prior adaptation to ultraviolet radiation. In 32 volunteers white blood cells, lymphocyte subpopulations, sIL2-R, sCD14, immunoglobulins and complement factor C3 were determined before and after a vacation in a country with abundant sunshine during winter. The subjects received relevant doses of UVB as confirmed by questionnaires, UVB-dosimetry and the significant increase of 25-hydroxyvitamin D. After vacation, there was a significant decrease of the CD4/8 ratio and the serum concentration of IgG. The serum concentration of sIL2-R, sCD14, IgA and C3 was increased after the journey. Sunshine exposure without prior adaptation may be responsible for significant alterations in the immune system in association with a vacation during winter.  相似文献   
62.
Abstract Immunological data have been suggested to be a potential tool in the diagnosis, classification and monitoring of periodontal diseases. However, the role of circulating antibodies in periodontal patients is poorly understood. Patients suffering from localized juvenile periodontitis (LJP) are often reported to show high titers of serum IgG antibodies against Aetinobaeillus actinomycetemcomitans (A. actinomycetemcotnitans), but several affected patients do not. Most studies use well-known reference strains of the bacterium for testing against the patients' sera. The aim of the present investigation was to study the relationship between serum IgG antibody levels to autologous A. actinomycetemcomitans strains and clinical attachment loss (CAL). In addition, we wanted to assess the patients’serum titers against 4 well-known reference strains of the bacterium as well as their general potential immunoglobulin response. Intravenous blood samples were taken from 23 LJP patients and 10 healthy individuals, and autologous A. actinomycetemcomitans strains were cultured from 18 of the L.JP patients. CAL was measured at 4 different sites around ail present teeth and assessed as a % of teeth with at least 1 site moderately ≥2<5 mm) or severely (≥5 mm) involved. An enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the serum titers of IgG antibodies to A. actinomycetemcomitans antigens. No significant correlation was found between serum IgG antibody titers to autologous strains and CAL. However, there was a trend that low responders had more moderately affected teeth than had high responders and patients with undetectable A. actinomycetemcomitans levels, which is in agreement with a hypothetically protective role of the antibodies. The total counts of immunoglobulin assessed in all participants showed that the predominant class was IgG and the reference group displayed significantly less (p<0.05) IgG and IgG1 counts than the LJP patients. Both the reaction pattern against reference and autologous strains varied widely. We conclude that the specific antibody response against A. actinomycetemcomitans shows a weak correlation to clinical attachment levels in LJP patients.  相似文献   
63.
64.
Skin infection in a man immunosuppressed by corticosteroid treatment was found to be due to Pseudallescheria boydii. Although treatment is often unsatisfactory, infection in this patient responded well to oral ketoconazole and topical miconazole.  相似文献   
65.
肿瘤患者医院感染的分析与预防措施   总被引:7,自引:2,他引:5  
目的了解肿瘤科医院感染特点,为临床减少肿瘤患者感染提供参考信息。方法以主动监测与系统回顾相结合的方法,对2005年全年入住肿瘤科2 679例患者的临床资料进行统计、分析、评定。结果2 679例肿瘤患者发生医院感染120例次,医院例次感染率为4.47%,其中感染1次者179例、2次者31例、≥3次者10例;以呼吸道感染占首位,其中上呼吸道38例、下呼吸道36例,其次为消化道10例、血液9例、手术切口感染8例、泌尿道6例和其他部位感染13例。结论提高机体免疫力、控制内源性感染,是预防与控制肿瘤患者感染的主要措施。  相似文献   
66.
Tumor cells infected with a retrovirus vector (VIK) containing the herpes simplex virus thymidine kinase (HSV-TK) gene can be selectively killed by treatment with nucleoside analogues, such as ganciclovir. To mediate delivery of the HSV-TK gene to "recipient" tumor cells, "donor" C6 rat glioma cells infected with the VIK vector (C6VIK) were superinfected with wild type Moloney murine leukemia virus (WT Mo-MLV). These modified donor cells (C6VIKWT) produced both wild type retrovirus and the VIK vector. In culture, C6VIKWT cells were 300-fold more sensitive to the toxicity of ganciclovir than were C6VIK cells, suggesting that the presence of wild type retrovirus contributed to the toxicity. Co-culture of C6VIKWT cells with the C6 subline, C6BAG, sensitized the latter to ganciclovir treatment. Nude mice inoculated subcutaneously with a mixture of C6VIKWT and C6BAG cells showed regression of subsequent tumors when treated with ganciclovir. The observations show that tumor cells modified in culture by infection with a retrovirus bearing the HSV-TK gene and wild type retrovirus are not only sensitive to ganciclovir, but can transfer this sensitivity to neighboring "naive" tumor cells in culture and in vivo.  相似文献   
67.
Summary The surfaces of 32 encrusted urinary catheters were examined by scanning electron microscopy to investigate the association of bacteria with the encrusting deposits. Deposits consisted of struvite crystals surrounded by aggregates of very small crystallites of hydroxyapatite. Underneath these minerals there was a layer of closely packed bacteria. Impressions of bacteria were also observed in hydroxyapatite. Crystals were often engulfed by the bacterial layer, which thus appeared to bind the crystals to each other and to the catheter surface. This thick layer of bacteria associated with crystals may protect both the bacteria from antibiotics and the crystals from acidic bladder washout solutions intended to dissolve them. Furthermore, the existence of this sessile population explains why urease-producing bacteria are not invariably detected in the urine of patients with encrusted catheters. The observation of this bacterial layer (or biofilm) by scanning electron microscopy provided direct evidence for infection being implicated in catheter encrustation.  相似文献   
68.
The incidence of upper respiratory tract infections (URTI) and salivary immunoglobulin A concentrations [IgAs] of nine individuals were examined during 12 weeks of moderate exercise training, and compared to ten sedentary controls. Changes in maximal oxygen uptake were assessed at initial, mid-point and final evaluations (T1–3), while changes in [IgAs] and salivary immunoglobulin concentration-salivary albumin concentration ratio ([IgAs]:[Albs]) were monitored at T1 and T3. During the 12 week period, symptoms of URTI were self-recorded daily. During the period of training the level of fitness significantly increased (P<0.05) in the exercise group. The number of days recording symptoms of influenza, but not of cold, and total light URTI symptoms was significantly reduced in the exercise group during the last weeks of training. A significant increase in [IgAs] and in [IgAs]:[Albs] was found in the exercise group after training. Both [IgAs] and [IgAs]:[Albs] were significantly related to the number of days showing symptoms of influenza (P<0.01) and the total number of days of sickness (P<0.05). These data provide quantitative support for the belief that regular, moderate exercise results in an increased [IgAs] at rest and [IgAs]:[Albs], which may contribute to a decreased risk of infection. Electronic Publication  相似文献   
69.
The DNA from several clinical isolates of varicella-zoster virus (VZV) were compared with the DNA from the vaccine strain VZV using three restriction endonucleases: BamHI, BgII, and HpaI. When electrophoresed through an agarose gel, the vaccine DNA digestion pattern was significantly different from the digestion patterns of the wild-type DNAs. Variations in the digestion pattern of the separate clinical isolates were also observed.  相似文献   
70.
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