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71.
Objectives and methods.The risk of second primary malignancies (SMN) was studied in a cohort of 4,416 one-year survivors of a breast cancer. The role of the menopausal status and of the initial treatment modalities (surgery, radiotherapy, and chemotherapy) was investigated. Results.Excluding second primary breast cancer and non-melanoma skin cancer, a total of 193 (4.4%) patients developed a SMN between 1973 and 1992, compared with 136 expected (Standardised Incidence Ratio, SIR=1.4, 95% CI (1.2–1.6)). No trend towards either an increase or a decrease was noted in the SIR with time after treatment (p=0.2). The greatest increase in the relative risk concerned soft tissue cancers (SIR=13.0, 95% CI: 6.8–22.3), followed by leukaemia (SIR=3.1, 95% CI: 1.7–5.0), melanoma (SIR = 2.7, 95% CI: 1.4–4.8), kidney (SIR=2.5, 95% CI: 1.2–4.5), ovary (SIR=2.0, 95% CI: 1.2–3.1) and uterine tumours (SIR=1.9, 95% CI: 1.4–2.5). The SIR was 3.0 (95% CI 1.8–4.7) in women under 40 at the time of the breast cancer, 1.9 (95% CI : 1.4 – 2.4) in those aged 40–49 and 1.2 (95% CI 1.0–1.4) in those aged 50 or more. In the 2,514 women who had received radiotherapy as initial treatment without chemotherapy, the SIR for all SMN was 1.6 (95% CI: 1.1–2.3) fold higher than in those who had not received radiotherapy as initial treatment. Conclusion.In conclusion, this study confirms the increased risk of second malignancies in women treated for a breast cancer, and particularly in those who were younger at the time of treatment for breast cancer. Our results also suggest that radiotherapy may play a role in the onset of these second lesions.  相似文献   
72.
The simultaneous use for the purpose of comparison of human bait catch and light trap collection for sampling anopheles populations specially the Anopheles gambiae s.l. in the area of Bignona, Senegal shows that: light traps provide more information on the specific composition of anopheles fauna; the performance of light traps and that of human baits are comparable indoor during the period of high density of anopheles. Outdoor, light traps catch fourth less females A. gambiae. But the two methods always vary in the same pattern and identically reflect the density variations of the populations; there is no significant difference between the repletion status, the physiological age and the sporozoite index of females A. gambiae s.l. collected with each of the 2 methods. Light trap collection may therefore be considered a reliable sampling method for A. gambiae s.l. specially inside houses in some areas where this method can efficiently permit to complete the human bait catch for a malaria transmission study.  相似文献   
73.
74.
BACKGROUND: Host-related and environment-related factors have been shown to play a role in the development of tuberculosis (TB), but few studies were carried out to identify their respective roles in resource-poor countries. METHODS: A multicentre case-control study was conducted in Guinée, Guinea Bissau, and The Gambia, from January 1999 to March 2001. Cases were newly detected smear positive TB patients. Two controls were recruited for each case, one within the household of the case, and one in the community. RESULTS: Regarding host-related factors, univariate analysis by conditional logistic regression of 687 matched pairs of cases and household controls showed that TB was associated with male sex, family history of TB, absence of a BCG scar, smoking, alcohol, anaemia, HIV infection, and history and treatment of worm infection. In a multivariable model based on 601 matched pairs, male sex, family history of TB, smoking, and HIV infection were independent risk factors of TB. The investigation of environmental factors based on the comparison of 816 cases/community control pairs showed that the risk of TB was associated with single marital status, family history of TB, adult crowding, and renting the house. In a final model assessing the combined effect of host and environmental factors, TB was associated with male sex, HIV infection, smoking (with a dose-effect relationship), history of asthma, family history of TB, marital status, adult crowding, and renting the house. CONCLUSION: TB is a multifactorial disorder, in which environment interacts with host-related factors. This study provided useful information for the assessment of host and environmental factors of TB for the improvement of TB control activities in developing countries.  相似文献   
75.
The natural history of renal function following orthotopic heart transplant   总被引:2,自引:0,他引:2  
BACKGROUND: The outcome of solid organ transplantation has dramatically improved after the introduction of the calcineurin inhibitor cyclosporine. With the increasing longevity of heart transplant recipients, the long-term effects of cyclosporine on renal function have become more evident. The natural history of kidney function following orthotopic heart transplant is not well defined and long-term follow up studies are scant. METHODS: We conducted an observational study on patients who received a heart transplant at Saint Louis University Hospital between January 1, 1983 and December 31, 1988. Patients were followed up for 15 yr or until death whichever occurred first. In order to assess the effect of heart transplantation and cyclosporine exposure on long-term renal function we restricted the statistical analysis to patients who survived the first year post-transplantation. RESULTS: A total of 68 patients received orthotopic heart transplants at Saint Louis University Hospital between 1983 and 1988. Forty-eight (71%) patients survived for more than 1 yr. All patients were treated with cyclosporine based triple immunosuppressive regimen, with gradual cyclosporine dose reduction over time. The mean duration of follow-up was 8 yr. The estimated GFR at 5 and 10 yr post-transplant were significantly lower than estimated GFR at baseline and 1 yr post-transplant. There was no significant difference between estimated GFR at 15 yr and estimated GFR at baseline or 1 yr post-transplant. The cumulative incidence of chronic renal failure (GFR < or = 29 mL/min/1.73 m2) at 5, 10 and 15 yr was 4.2, 10.4 and 12.5%, respectively (p < 0.05). The cumulative incidence of severe chronic renal failure (GFR < or = 15 mL/min/1.73 m2) at 5, 10 and 15 yr was 2.1, 8.3 and 8.3%, respectively. The mortality rate was 8, 37, and 52% at 5, 10, and 15 yr, respectively. The 10 and 15 yr survivors had an estimated GFR at 1 yr post-transplant that was significantly higher than the non-survivors. Age, pre-transplantation estimated GFR, pre-transplantation diabetes and pre-transplantation hypertension are risk factors associated with > or = 10 mL/min/1.73 m2 decrement in estimated GFR. CONCLUSION: Heart transplant survivors beyond the first year post-transplant have a significant decrease in renal function and significant mortality observed over time. Age, pre-transplant GFR, pre-transplant diabetes and pre-transplant hypertension are important risk factors for decrement in renal function.  相似文献   
76.
A series of atomistic simulations was performed to assess the ability of the Schulten dissolved organic matter (DOM) molecule, a well-established model humic molecule, to reproduce the physical and chemical behavior of natural humic substances. The unhydrated DOM molecule had a bulk density value appropriate to humic matter, but its Hildebrand solubility parameter was lower than the range of current experimental estimates. Under hydrated conditions, the DOM molecule went through conformational adjustments that resulted in disruption of intramolecular hydrogen bonds (H-bonds), although few water molecules penetrated the organic interior. The radius of gyration of the hydrated DOM molecule was similar to those measured for aquatic humic substances. To simulate humic materials under aqueous conditions with varying pH levels, carboxyl groups were deprotonated, and hydrated Na+ or Ca2+ were added to balance the resulting negative charge. Because of intrusion of the cation hydrates, the model metal-humic structures were more porous, had greater solvent-accessible surface areas, and formed more H-bonds with water than the protonated, hydrated DOM molecule. Relative to Na+, Ca2+ was both more strongly bound to carboxylate groups and more fully hydrated. This difference was attributed to the higher charge of the divalent cation. The Ca-DOM hydrate, however, featured fewer H-bonds than the Na-DOM hydrate, perhaps because of the reduced orientational freedom of organic moieties and water molecules imposed by Ca2+. The present work is, to our knowledge, the first rigorous computational exploration regarding the behavior of a model humic molecule under a range of physical conditions typical of soil and water systems.  相似文献   
77.
This study aimed at assessing envenomations caused by snakebite in the Gabriel Touré hospital between January 1998 and December 1999. We included in total 112 victims of snakebites proved by the identification of the snake, the fangs traces and envenomation signs. The bites concerned 34 women (30.36%) versus 78 men (69.64%) from the Bamako district, while 66.7% were from a rural environment. The farmers were the most affected category (35.1%). The bite concerned the lower limb in 83.3% of the cases. Snakes such as Echis ocellatus, Bitis arietans, Naja nigricollis and N. katiensis caused the envenomations. The viperine syndrome dominated the clinical picture; its severity depended on the bleeding stage and the delay of administration of the antivenom serum (AVS) after the envenomation: 19 hours for Echis sp. and 2 hours for Naja sp. This study shows that the envenomation accidents caused by snakes are frequent with a lethality rate of 9.8%.  相似文献   
78.
In 1998, circulation of the Rift Valley Fever (RVF) virus was revealed in Diawara by detection of IgM antibodies in sheep and isolation of the virus from mosquitoes caught outside a village. A seroprevalence study was carried out. Finger-prick blood samples, individual and collective details were obtained. One thousand five hundred twenty people (6 months - 83 years) were included. Overall prevalence in this group was approximately 5.2%. The prevalence in infants (6 months - 2 years) was 8.5%. Age, gender, contact with a pond, presence of sheep, and abortion among sheep, and individual or collective travel history were not statistically associated with prevalence. Prevalence increased significantly when the distance to a small ravine, located in the middle of the village, decreased. The results suggest a low, recent, not endemic circulation of the virus. Culex quinquefasciatus was captured near the ravine. This mosquito, similar to Culex pipiens, can play a similar role in human-to-human transmission of the RVF virus.  相似文献   
79.
80.
Eye injuries, most of them preventable, are particularly severe in Africa, because of the risks of infection and delay in treatment. We report a 16-month (March 1997-June 1998) prospective observational survey of eye injuries in children up to the age of 15 years at Treichville-Abidjan University Hospital. During this period, 62 children were treated for these injuries. Ocular traumas represented 4% (n = 245) of new admissions in ophthalmology, and 29% of these injuries occurred in children. The sex ratio was 5:2 boys to girls, and their mean age was 8.66 +/- 3.56 years. Eye injuries occurred most often during play (84%, n = 52). More than 85% (n = 53) of children were alone or without adult supervision at the time of the injury. The causal agent was most often wood (35%) followed by metal (29%). The mean time from injury to hospital admission was 1.8 +/- 0.77 day. Only 19% of patients were admitted the day of injury. Most patients (66%) first sought treatment in a primary care centre. More than 70% (n = 44) of injuries necessitated hospitalisation. Open eyeball wounds were the most common injury (53%) and were associated with endophthalmitis in 16%. The mean recovery of visual acuity was 0.1. At admission, 40 of the injured eyes (64.5%) had monocular blindness; six recovered, for a final blindness rate of 55%. Injuries associated with wooden objects had a final blindness rate of 77% and play-related injuries 63%. The primary posttraumatic sequelae were corneal scars. Eyeball phthysis (14.5%) was secondary to 8 open wounds of the eyeball and one postcontusion retinal detachment. Eye injuries remain a major cause of monocular blindness in children in Cote d'Ivoire. Most of them can be prevented by relatively simple measures including supervision of children and rapid hospitalisation when injury occurs.  相似文献   
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