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Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children.  相似文献   
3.
The effect of a two day fast on maternal plasma volume and plasma protein concentration was explored in pregnant rats. Fasting between days 17 and 19 of gestation prevented the rise in plasma volume observed in ad libitum fed rats. Plasma protein concentration declined between day 17 and day 19 in both fasted and not fasted rats. Placental weight was not reduced by fasting during this stage of gestation. Fetal weight in the fasted group was 91% of the fetal weight of the ad libitum fed group. These results show that acute undernutrition, like longer term food or protein restriction, can prevent adequate plasma volume expansion and slow fetal growth.  相似文献   
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An 87-year-old woman, who had undergone cataract surgery and vitrectomy OD two years previously, had a blind, painful right eye secondary to intraocular hemorrhage and glaucoma. At the initial examination, a flat area of darkly pigmented tissue was noted at the wound site of the previous cataract surgery, and uveal prolapse was diagnosed. One year later, pigmented tissue was also seen at the inferior limbus. Intraocular malignant melanoma was considered, and the eye was enucleated. Histologic study revealed areas of hemorrhage and epithelioid malignant melanoma. It is important to recognize that prolapse of tissue at a surgical wound site may represent an extension of an intraocular malignancy.  相似文献   
6.
A case of spontaneous rupture of the spleen as a complication and presenting factors of systemic amyloidosis is reported with a review of the pertinent literature. the sequelae of amyloid involvement of the spleen is discussed with emphasis on possible mechanisms involved in the causation of spontaneous rupture of this organ.  相似文献   
7.
In a retrospective study of 223 testis cancer survivors and 120 controls matched sociodemographically, we examined the relative impact of sociodemographic and clinical factors on long-term outcomes in the areas of sexual function, relationships, employment, and mental outlook. For most of the survivors, testis cancer did not lead to unemployment (4.5%), divorce (6.8%), or disabling psychological problems. Multivariate analysis results confirm that cancer survivors report significantly more infertility and sexual performance distress, but not more desire distress, than the control group. Survivors' sexual impairment varied according to treatment received (and therefore histologic factors) and sociodemographic variables. Parental status (not having children) and education (college or less) independently predict infertility distress, whereas education and lower occupational level independently predicted sexual performance distress. Adjusting for socioeconomic status (SES), the men with advanced testis cancer who received chemotherapy and standard retroperitoneal lymph node dissection (RPLND) had significantly more infertility and performance distress than those men who received other treatments. Neither the treatment or SES variables predicted disrupted relationships or a deteriorated mental outlook. However, men with sexual impairment distress were more likely to report strained relationships and a pessimistic mental outlook. These findings have implications for treatment decisions and can be used to identify subgroups of survivors who could benefit from counseling and sexual rehabilitation services.  相似文献   
8.
Over the past 10–15 years, there has been increasing interest in the health problems of performing artists. In this review, I will discuss the major playing-related disorders seen in instrumental musicians. Among the 672 instrumentalists evaluated, the major diagnoses identified included musculoskeletal disorders in 64%, peripheral nerve problems in 22.5%. and focal dystonia in 7%. Sixty percent of instrumentalists were female although males predominate in the group with focal dystonia. The average age of those evaluated was 32 years. Among musculoskeletal disorders overuse syndrome is the most common. Frequent peripheral nerve disorders include thoracic outlet syndrome, carpal tunnel syndrome, and ulnar neuropathy. A characteristic distribution of symptoms and signs is identified for each instrument group. Electrodiagnostic studies are an important part of the evaluation of these disorders. With carefully designed treatment, the majority of instrumental musicians can be returned to full and pain-free playing activities. The success rate is highest in some entrapment neuropathies but remains low in focal dystonia. © 1994 John Wiley & Sons, Inc.  相似文献   
9.
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted.  相似文献   
10.
From a study of 71 HIV-1-infected patients receiving abacavir in combination with 1 of 5 different HIV-1 protease inhibitors (indinavir, ritonavir, saquinavir, nelfinavir, or amprenavir), we found that the baseline HIV-1 RNA levels were highly predictive of the viral decay rates. The baseline HIV-1 RNA levels were negatively correlated with the first phase viral decay rates (r = -0.77, P < 0.001) and positively correlated with the second phase viral decay rates (r = 0.68, P < 0.001). In addition, the first phase viral decay rate was positively correlated with CD4+ cell increases. No significant correlation was found between viral decay rates and longer term (24 weeks) virologic responses, and no difference in viral decay rates was found among the 5 study regimens. These data suggest that the potency of the 5 treatment regimens was similar and was not predictive of long-term virologic failure.  相似文献   
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