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81.
We retrospectively examined the effectiveness of prophylaxis with cotrimoxazole in preventing Pneumocystis carnii pneumonia in recipients of kidney and combined kidney-pancreas transplants between 1985 and 1989. Cotrimoxazole prophylaxis (480 mg daily or 300 mg/m2), when used, was started within 2 months after transplantation and usually continued until 6 months after surgery. Eight (3.7%) of the 214 patients who were not given prophylaxis were infected with Pneumocystis carinii, and there were 4 fatalities (50% mortality). There were no cases among the 161 patients given prophylaxis (P 0.03). No serious adverse effects were noted in the prophylaxis group. It is concluded that prophylaxis against Pneumocystis carinii infection is well tolerated and should be given as soon as possible to all organ transplant recipients for at least 6 months.  相似文献   
82.
83.
Methanol is a widely used solvent and a potential fuel for motor vehicles. Human kinetic data of methanol are sparse. As a basis for biological exposure monitoring and risk assessment, we studied the inhalation toxicokinetics of methanol vapor in four female and four male human volunteers during light physical exercise (50 W) in an exposure chamber. The relative uptake of methanol was about 50% (range 47-53%). Methanol in blood increased from a background level of about 20 to 116 and 244 microM after 2 h exposure at 0, 100 ppm (131 mg/m3) and 200 ppm (262 mg/m3), respectively. Saliva showed substantially higher levels than blood immediately after exposure. This difference disappeared in a few minutes; thereafter the concentrations and time courses in blood, urine, and saliva were similar, with half times of 1.4, 1.7, and 1.3 h, respectively. The postexposure decrease of methanol in exhaled air was faster, with a half time of 0.8 h. The methanol concentrations were approximately twice as high in all four types of biological samples at 200 compared to 100 ppm. No increase in urinary formic acid was seen in exposed subjects. Our study indicates non-saturated, dose-proportional kinetics of methanol up to 200 ppm for 2 h. No gender differences were detected. Similar, parallel patterns were seen with regard to the methanol time courses in blood, urine, and saliva, whereas the concentration in exhaled air decreased markedly faster. Thus, apart from blood and urine, saliva also seems suitable for biomonitoring of methanol exposure.  相似文献   
84.
PURPOSE: Legumain, a novel asparaginyl endopeptidase, has been observed to be highly expressed in several types of tumors including colorectal cancer. However, there is no study examining the relationship of legumain expression to clinocopathologic and biological variables in colorectal cancers. EXPERIMENTAL DESIGN: We investigated legumain expression in 164 primary colorectal cancers, 34 corresponding distant normal mucosa samples, 89 adjacent normal mucosa samples, and 33 lymph node metastases using immunohistochemistry. We also did Western blotting analysis on three additional colorectal cancers and three colonic cell lines. RESULTS: Legumain expression was increased in primary tumors compared with distant or adjacent normal mucosa (P < 0.05), but there was no significant change between primary tumors and metastases (P > 0.05). Legumain expression was positively related to poorer differentiation/mucinous carcinoma (P = 0.04), higher degree of necrosis (P = 0.03) and apoptosis (P < 0.0001), positive proliferating cell nuclear antigen (P < 0.0001) and p53 expression (P = 0.049), and had a positive tendency towards stromelysin 3 (P = 0.058) and PINCH positivity (P = 0.05). The patients with tumors that showed both weak and lower percentage of the legumain expression, either in tumor (P = 0.01) or in stroma (P = 0.04), had a better prognosis. CONCLUSIONS: The legumain expression may be involved in colorectal cancer development and have a prognostic value in the patients.  相似文献   
85.

Background  

Ovarian carcinomas from 30 BRCA1 germ-line carriers of two distinct high penetrant founder mutations, 20 carrying the 1675delA and 10 the 1135insA, and 100 sporadic cases were characterized for somatic mutations in the TP53 gene. We analyzed differences in relation to BRCA1 germline status, TP53 status, survival and age at diagnosis, as previous studies have not been conclusive.  相似文献   
86.
A pharmacological, behavioural and nursing intervention strategy was evaluated for prevention of cisplatin (50 mg m-2) induced emesis in ovarian cancer patients. 46 patients received metoclopramide 2.5 mg kg-1 i.V., b.i.d., dexamethasone 20 mg i.V., lorazepam and biperiden as well as training in relaxation, nutritional advice and continuity in nursing care. Controls (n = 34) received standard treatment (metoclopramide 10-20 mg i.v. or dixyracin 20 mg i.V.). The intensity and duration of nausea and vomiting were significantly lower and measures of quality of life higher for patients on the experimental ward during the three cycles that were studied. No significant changes in emesis were observed between the cycles. There was no correlation between emesis and any of the parameters of quality of life measured. The reliability and validity of nausea ratings are discussed and we suggest that an underreporting of nausea and vomiting might be common.  相似文献   
87.
Objectives: The etiology of breast cancer is only partially understood. Based on the findings that pregnancies reduce breast cancer risk, a possible inverse association between exposure to the placental hormone human chorionic gonadotropin (hCG) and the risk of breast cancer has been suggested. Hydatidiform mole, a gestational trophoblastic disease, is associated with a high expression of hCG. We performed a population-based cohort study in which women with a history of hydatidiform mole were followed up for future cancer outcomes. Methods: All 3371 women with a notification of hydatidiform mole in the Swedish Cancer Registry between 1958 and 1993 were followed up for future cancer outcomes by record linkages within the registry. Results: In a total of 57,075 person-years of follow-up, 59 women had a diagnosis of breast cancer during follow-up, yielding an overall standardized incidence ratio of 1.3 (95% CI 1.0–1.7). Conclusion: This finding is not consistent with the hypothesis of a protective effect of hCG exposure on breast cancer risk, but rather suggests an adverse association.  相似文献   
88.
Background: Concerns remain about the human reproductive toxicity of the widespread per- and polyfluoroalkyl substances (PFAS) during early stages of development.Objectives: We examined associations between maternal plasma PFAS levels during early pregnancy and male offspring reproductive function in adulthood.Methods: The study included 864 young men (age range:18.9–21.2 y) from the Fetal Programming of Semen Quality (FEPOS) cohort established between 2017 and 2019. Plasma samples from their mothers, primarily from the first trimester, were retrieved from the Danish National Biobank and levels of 15 PFAS were measured. Seven PFAS had detectable levels above the limit of detection in >80% of the samples and were included in analyses. Semen quality, testicular volume, and levels of reproductive hormones and PFAS were assessed in the young men. We used weighted quantile sum (WQS) regression to estimate the associations between combined exposure to maternal PFAS and reproductive function, and negative binomial regression to estimate the associations of single substances, while adjusting for a range of a priori–defined fetal and postnatal risk factors.Results: By a 1-unit increase in the WQS index, combined maternal PFAS exposure was associated with lower sperm concentration (8%; 95% CI: 16%, 1%), total sperm count (10%; 95% CI: 17%, 2%), and a higher proportion of nonprogressive and immotile sperm (5%; 95% CI: 1%, 8%) in the young men. Different PFAS contributed to the associations with varying strengths; however, perfluoroheptanoic acid was identified as the main contributor in the analyses of all three outcomes despite the low concentration. We saw no clear association between exposure to maternal PFAS and testicular volume or reproductive hormones.Discussion: In a sample of young men from the general Danish population, we observed consistent inverse associations between exposure to maternal PFAS and semen quality. The study needs to be replicated in other populations, taking combined exposure, as well as emerging short-chain PFAS, into consideration. https://doi.org/10.1289/EHP10285  相似文献   
89.
Highly pathogenic avian influenza viruses (HPAIVs) of hemagglutinin type H5 and clade 2.3.4.4b have widely spread within the northern hemisphere since 2020 and threaten wild bird populations, as well as poultry production. We present phylogeographic evidence that Iceland has been used as a stepping stone for HPAIV translocation from northern Europe to North America by infected but mobile wild birds. At least 2 independent incursions of HPAIV H5N1 clade 2.3.4.4b assigned to 2 hemagglutinin clusters, B1 and B2, are documented for summer‒autumn 2021 and spring 2022. Spread of HPAIV H5N1 to and among colony-breeding pelagic avian species in Iceland is ongoing. Potentially devastating effects (i.e., local losses >25%) on these species caused by extended HPAIV circulation in space and time are being observed at several affected breeding sites throughout the North Atlantic.  相似文献   
90.
PurposeDefects in the iridocorneal angle tissues, including the trabecular meshwork (TM) and Schlemm''s canal (SC), impair aqueous humor flow and increase the intraocular pressure (IOP), eventually resulting in glaucoma. Activation of endothelial tyrosine kinase receptor Tie2 by angiopoietin-1 (Angpt1) has been demonstrated to be essential for SC formation, but roles of the other two Tie2 ligands, Angpt2 and Angpt4, have been controversial or not yet characterized, respectively.MethodsAngpt4 expression was investigated using genetic cell fate mapping and reporter mice. Congenital deletion of Angpt2 and Angpt4 and tamoxifen-inducible deletion of Angpt1 in mice were used to study the effects of Angpt4 deletion alone and in combination with the other angiopoietins. SC morphology was examined with immunofluorescent staining. IOP measurements, electron microscopy, and histologic evaluation were used to study glaucomatous changes.Results Angpt4 was postnatally expressed in the TM. While Angpt4 deletion alone did not affect SC and Angpt4 deletion did not aggravate Angpt1 deletion phenotype, absence of Angpt4 combined with Angpt2 deletion had detrimental effects on SC morphology in adult mice. Consequently, Angpt2−/−;Angpt4−/− mice displayed glaucomatous changes in the eye. Mice with Angpt2 deletion alone showed only moderate SC defects, but Angpt2 was necessary for proper limbal vasculature development. Mechanistically, analysis of Tie2 phosphorylation suggested that Angpt2 and Angpt4 cooperate as agonistic Tie2 ligands in maintaining SC integrity.ConclusionsOur results indicated an additive effect of Angpt4 in SC maintenance and Tie2 activation and a spatiotemporally regulated interplay between the angiopoietins in the mouse iridocorneal angle.  相似文献   
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