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21.
SMJ Mortazavi MA Mosleh-Shirazi AR Tavassoli M Taheri AR Mehdizadeh SAS Namazi A Jamali R Ghalandari S Bonyadi M Haghani M Shafie 《Dose-response》2013,11(2):281-292
The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1st phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2nd phase, 30 male rats were divided into 2 groups of 15 animals. The 1st group received microwave exposure. The 2nd group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response. 相似文献
22.
S Garcovich AR Di Giampetruzzi G Antonelli A Garcovich B Didona 《Journal of the European Academy of Dermatology and Venereology》2010,24(8):881-884
Background Pityriasis rubra pilaris (PRP) is a rare inflammatory dermatosis with frequent clinical presentation as erythroderma. Conventional systemic treatment is often unsatisfactory and limited by long‐term toxicity. The use of tumour necrosis factor (TNF) antagonists has been reported previously in single cases, but lacking long‐term follow‐up or comparison between different biological agents. Objectives To assess the long‐term efficacy and safety of TNF‐alpha antagonist, infliximab and etanercept, either in monotherapy or in combination therapy of severe, refractory adult‐onset PRP. Methods Seven patients of adult‐onset PRP, six newly diagnosed type‐I and 1 type‐II, which were resistant or ineligible to conventional systemic treatment, received a single course of infliximab or etanercept therapy, alone or in combination with low‐dose acitretin (>0.25 mg/kg/daily). After complete remission and treatment discontinuation, a follow‐up period of 12 months was evaluated for relapses. Results Six patients obtained complete remission after a single course of anti‐TNF‐alpha therapy: mean therapy duration was 19.3 weeks (range 6–48 weeks). All patients obtained significant clearing (>75% of body surface area) of skin lesions at week 12. Two patients with marked keratoderma developed localized disease recurrence during treatment. During follow‐up, only a single patient, affected by type II PRP, had disease relapse. Conclusions Both TNF‐alpha antagonists proved successful for the treatment of refractory, adult‐onset PRP, yielding complete and persistent clinical responses in type‐I PRP. Infliximab was associated with a more rapid onset of action, while treatment duration was comparable with etanercept. PRP type II warranted long‐term therapy and showed relapse after drug discontinuation. 相似文献
23.
Nelson KE Galai N Safaeian M Strathdee SA Celentano DD Vlahov D 《American journal of epidemiology》2002,156(7):641-653
Although the incidence of and mortality from acquired immunodeficiency syndrome have declined recently in the United States, data are needed on the incidence of human immunodeficiency virus (HIV) and risk behaviors among injection drug users (IDUs). The authors studied the temporal trends of HIV incidence and risk behavior, ascertained through semiannual confidential interviews, between 1988 and 1998 in a cohort of 1,532 HIV-seronegative IDUs in Baltimore, Maryland. An additional 338 HIV-negative drug users were recruited in 1994 and were studied by using the same methods. Overall, 277 persons seroconverted to HIV during 8,826.45 person-years of follow-up, an incidence of 3.14 per 100 person-years. The incidence per 100 person-years declined over time from 4.45 in 1988-1990 to 3.35 in 1991-1994 to 1.84 in 1995-1998, a decline of 12% per year. HIV infections were associated with injection of cocaine, more frequent injection, needle sharing, and injection in a shooting galley. Sexual behavior variables associated with HIV incidence included a sexually transmitted infection, male homosexual behavior, and sex with another IDU. These data suggest that high-risk behavior and HIV incidence among IDUs have decreased recently in Baltimore. Nevertheless, additional prevention strategies are needed in these populations. 相似文献
24.
Benzo[a]pyrene at an environmentally relevant dose is slowly absorbed by, and extensively metabolized in, tracheal epithelium 总被引:2,自引:0,他引:2
Gerde P; Muggenburg BA; Thornton-Manning JR; Lewis JL; Pyon KH; Dahl AR 《Carcinogenesis》1997,18(9):1825-1832
While tobacco smoke has been conclusively identified as a lung carcinogen,
there is much debate over which smoke constituent(s) are primarily
responsible for its carcinogenicity. Previous studies in our laboratory
suggested that highly lipophilic carcinogens are slowly absorbed in the
thicker epithelium of the conducting airways, potentially allowing for
substantial local metabolism. The bioactivation of polycyclic aromatic
hydrocarbons in airway epithelium may, hence, be important in tobacco
smoke-induced carcinogenesis. In the present study, the hypothesis of slow
absorption and substantial local metabolic activation of highly lipophilic
carcinogen in airway epithelium was tested in dogs. A single dose of
tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid
suspension was instilled in the trachea, just anterior to the carina. At
intervals of a few minutes up to 30 min over a 3-h period, blood samples
were drawn from the azygous vein, which drains the area around the point of
instillation, and from the systemic circulation. Tissue samples were taken
at the end of the experiment. The concentration of BaP with depth into the
tracheal mucosa was determined with autoradiography. BaP was slowly
absorbed into the trachea with a half-time of approximately 73 min, which
is consistent with diffusion-limited passage through the epithelium and
lead to local doses in the tracheal epithelium that were more than a
1000-fold those of other tissues. The long retention of BaP in the
epithelium provided the local metabolizing enzymes with high substrate
levels over a long period, resulting in extensive metabolism. At 3 h after
the exposure, 23% of the BaP-equivalent activity remained in the tracheal
mucosa. Of this fraction, 13% was parent compound, 28% was organic
extractable, 31% was water-soluble, and 28-7% of the instilled dose was
bound to tracheal tissues. These results explain the tendency of highly
lipophilic carcinogens, such as BaP, to induce tumors at the site of entry
and, furthermore, indicate that the highly lipophilic components of tobacco
smoke and polluted air may be the most important contributors to lung
tumors of the conducting airways.
相似文献
25.
MT Bardella N Molteni L Prampolini AM Giunta AR Baldassarri D Morganti PA Bianchi 《Archives of disease in childhood》1994,70(3):211-213
The use of follow up studies was evaluated in 128 patients with coeliac disease during their first visit to a department for adults. The original diagnosis had been made in childhood in all patients. Fifty eight (45%) of the subjects were following a gluten free diet, 23 (18%) were following a gluten free diet but with occasional gluten consumption, and 47 (37%) had adopted an unrestricted, gluten containing diet for a mean of 11.2 years. There was no correlation in individual subjects between the presence of symptoms, biochemical and immunological abnormalities, severity of histological findings, and the amount of dietary gluten, despite the greater frequency of symptoms in the group following an unrestricted diet than in the other two groups. Short stature and epilepsy with cerebral calcifications only occurred in patients following an unrestricted diet. As only diagnosis based on two or three biopsy samples and regular follow up correlated positively with dietary compliance, it is suggested that a histologically confirmed diagnosis of coeliac disease and regular lifelong follow up are essential in the management of these patients. 相似文献
26.
STOTT DJ; MCLELLAN AR; FINLAYSON J; CHU P; ALEXANDER WD 《QJM : monthly journal of the Association of Physicians》1991,78(1):77-84
The clinical and biochemical characteristics of 15 elderly patientswith low levels of thyrotrophin (TSH) (<0.1 mU/L) but normalfree tri-iodothyronine, (T3) and free thyroxine (T4) (groupS) were compared with 10 euthyroid subjects (group E) and 10hyperthyroid patients (group T). Free T3 and free T4 were significantlyhigher (p<0.05) in group S(6.3±0.5 and 18.6±1.0pmol/l, respectively) than in group E(4.6±0.3, 12.6+0.6).In common with elderly hyperthyroid patients (group T)patientsin group S had few signs or symptoms of thyrotoxocosis, butthe Wayne score (clinical index of hyperthyroidism) was higherin group S than in euthyroid subjects (p<0.05). Thyroid microsomal,thyrogolobulin or thyrotrophin receptor antibodies were commonin group T (n=9)but not in groups S(n=2) or E(n=1). This suggestsa low prevalence of Graves' disease in group S compared to groupT. Combined thyrotrophin releasing hormone (TRH; 200 µgi.v.) and gonadotrophin releasing hormone GnRH; 100 µgi.v.) tests were performed; no cases of low TSH due to hypopituitarismwere identified in group S. During a mean of 7.9 (412)months of observation TSH reverted to the normal range (>0.2mU/L)in 7 of 15 patients in group S; thyroid hormone concentrationsrose above the normal range in four, however, only two patientsrequired treatment for hyperthyroidism. It is unlikely thatthe suppressed TSH of patients in group S was due to mild thyroidhormone excess; although this is often a transitory phenomenon,these patients are at increased risk of developing overt hyperthyroidism. 相似文献
27.
28.
Galai N Safaeian M Vlahov D Bolotin A Celentano DD;ALIVE Study 《American journal of epidemiology》2003,158(7):695-704
The objective of this study was to characterize longitudinal patterns of drug injection behavior for individuals and to identify their early determinants. Participants were 1,339 injection drug users recruited into the AIDS Link to Intravenous Experience (ALIVE) Study in Baltimore, Maryland, through community outreach efforts. The study was initiated in 1988, and follow-up continued through 2000, with semiannual visits. Patterns of self-reported drug injection (yes/no) were defined for each participant, based on the number of drug-use transitions. The effect of baseline factors was assessed using multinomial logistic regression models. Over the 12-year study period, four patterns were noted: 29% of participants remained persistent drug injectors, 20% ceased injection, 14% relapsed once, and 37% had multiple transitions. Persistent injectors had the shortest follow-up and the highest mortality. For persons who changed their behavior, 3.4 years elapsed before their first cessation attempt, on average. Factors differentiating the groups included history of incarceration, young age, participation in drug treatment programs, recent overdose, and commercial sex. The observed long-term injection patterns are consistent with the view of drug addiction as a chronic disease. This view emphasizes the need for prolonged efforts to sustain cessation and to prevent adverse health and social outcomes among injection drug users. 相似文献
29.
WVBS Ramalingam D Chikara G Rajagopal AVSM Prof AR Mehta S Sarkar 《Medical Journal Armed Forces India》2007
Background: Stage III and IV cancers of larynx and hypopharynx often require total laryngectomy which leaves the patient with severe communication handicap. In such laryngectomised patients tracheo-esophageal puncture is the best way for voice rehabilitation using either Blom-Singer® prosthesis or Provox® indwelling valve. 相似文献
30.
Lineage-restricted regulation of the murine SCL/TAL-1 promoter 总被引:10,自引:2,他引:10
Bockamp EO; McLaughlin F; Murrell AM; Gottgens B; Robb L; Begley CG; Green AR 《Blood》1995,86(4):1502-1514