Its incidence has decreased in recent decades due to advances in the treatment of patients with primary rectal cancer, but LRRC still occurs in 6-10% of these patients. LRRC is often accompanied by ...severe, progressive pain and has a major impact on quality of life. Curative treatment is possible based on surgical resection combined with chemoradiotherapy. Radical resection is the most important prognostic factor in curative treatment. Neo-adjuvant systemic therapy may further improve outcomes in LRRC patients. Many patients are not eligible for surgical treatment due to the presence of metastases or irresectability of the local recurrence. These patients should receive optimal palliative care for the disabling pain. Radiotherapy is effective against local pain in around 75% of patients but the duration of palliation is limited.
Since patients with incurable metastatic colorectal cancer (CRC) only have a relatively limited life expectancy, and resection of the primary tumour is accompanied by both morbidity and mortality, it ...is under debate whether resection of the primary tumour has an effect on survival or quality of life. The rationale behind the resection strategy is that prophylactic surgery prevents future complications. With current new chemotherapy regimens, a relatively low number of patients with metastatic CRC require surgery for their primary tumour. Many studies concerning the management of incurable stage IV CRC have been performed and most studies suggest a survival benefit for patients undergoing surgical resection of the primary tumour compared with those who received palliative treatment. However, in stage IV CRC with unresectable metastases, the role of a palliative resection of the primary tumour has never been assessed properly. Because randomised clinical trials are lacking, it is difficult to draw conclusions from the present literature.
Diverse natural and anthropogenic activities in the Highveld of South Africa contribute to elevated levels of inorganic and organic gaseous pollutant species. The primary aims of this investigation ...were to determine spatial and temporal distributions of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3), as well as benzene, toluene, ethylbenzene and xylene (BTEX) in this area. Sampling was conducted on a monthly basis for a year at eight strategically selected sites. The highest NO2, SO2 and BTEX concentrations were measured at sites with significant local sources and/or sites impacted by more remote sources, as indicated by overlay back trajectories. O3 concentrations were found to be lower at sites with high levels of NO2, SO2 and BTEX. NO2 and SO2 peaked during winter, while O3 peaked in spring. NO2 and SO2 temporal concentration variations were ascribed to differences in seasonal meteorological conditions, as well as additional sources in winter. The O3 peak coincided with a seasonal CO peak, which was identified as an important precursor for O3 formation. No distinct seasonal trend was observed for BTEX. The annual average concentrations for SO2, NO2, O3 and benzene were below the South African annual standards at all sites.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Diverse natural and anthropogenic activities in the Highveld of South Africa contribute to elevated levels of inorganic and organic gaseous pollutant species. The primary aims of this investigation ...were to determine spatial and temporal distributions of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3), as well as benzene, toluene, ethylbenzene and xylene (BTEX) in this area. Sampling was conducted on a monthly basis for a year at eight strategically selected sites. The highest NO2, SO2 and BTEX concentrations were measured at sites with significant local sources and/or sites impacted by more remote sources, as indicated by overlay back trajectories. O3 concentrations were found to be lower at sites with high levels of NO2, SO2 and BTEX. NO2 and SO2 peaked during winter, while O3 peaked in spring. NO2 and SO2 temporal concentration variations were ascribed to differences in seasonal meteorological conditions, as well as additional sources in winter. The O3 peak coincided with a seasonal CO peak, which was identified as an important precursor for O3 formation. No distinct seasonal trend was observed for BTEX. The annual average concentrations for SO2, NO2, O3 and benzene were below the South African annual standards at all sites.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Diverse natural and anthropogenic activities in the Highveld of South Africa contribute to elevated levels of inorganic and organic gaseous pollutant species. The primary aims of this investigation ...were to determine spatial and temporal distributions of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3), as well as benzene, toluene, ethylbenzene and xylene (BTEX) in this area. Sampling was conducted on a monthly basis for a year at eight strategically selected sites. The highest NO2, SO2 and BTEX concentrations were measured at sites with significant local sources and/or sites impacted by more remote sources, as indicated by overlay back trajectories. O3 concentrations were found to be lower at sites with high levels of NO2, SO2 and BTEX. NO2 and SO2 peaked during winter, while O3 peaked in spring. NO2 and SO2 temporal concentration variations were ascribed to differences in seasonal meteorological conditions, as well as additional sources in winter. The O3 peak coincided with a seasonal CO peak, which was identified as an important precursor for O3 formation. No distinct seasonal trend was observed for BTEX. The annual average concentrations for SO2, NO2, O3 and benzene were below the South African annual standards at all sites.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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