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101.
The survival of patients with Hodgkin's disease has dramatically improved over the past 30 years because of advances in treatment. However, concern for the risk of long-term complications has resulted in a number of trials to evaluate reduction of therapy. The consequences of these trials on recurrence, development of long-term complications, and survival remain unknown. One major consequence of successful treatment of Hodgkin's disease is the development of second malignant neoplasms. We sought to determine the factors most important for development of second tumors in pathologically staged and treated Hodgkin's disease patients followed for long intervals to provide background information for future clinical trials and guidelines for routine patient follow-up. Between April 1969 and December 1988, 794 patients with laparotomy staged (PS) IA-IIIB Hodgkin's disease were treated with radiation therapy (RT) alone or combined radiation therapy and chemotherapy (CT). There were 8,500 person-years of follow-up (average of 10.7 person-years per patient). Age and gender-specific incidence rates were multiplied by corresponding person-years of observation to obtain expected numbers of events. Observed to expected results were calculated by type of treatment, age at treatment, sex, and time after Hodgkin's disease. Absolute (excess) risk was expressed as number of excess cases per 10,000 person-years. Seventy-two patients have developed a second malignant neoplasm. Eight patients developed acute leukemia, 10 had non-Hodgkin's lymphoma (NHL), and 53 patients developed solid tumors at a median time of 5 years, 7.25 years, and 12.2 years, respectively, after Hodgkin's disease. One patient developed multiple myeloma 16.5 years after Hodgkin's disease. The relative risk (RR) of developing a second malignancy was 5.6. The absolute excess risk per 10,000 person-years (AR) of developing a second malignancy was 69.6 (7.0% excess risk per person per decade of follow-up). The highest RR occurred for the development of leukemia (RR = 66.2), however because of the low expected risk, the AR was only 9.3. The RR of solid tumors after Hodgkin's disease was lower (4.7); however, the AR was greater (49) than for acute leukemia. Among the solid tumors, breast, gastrointestinal, lung, and soft tissue cancers had the highest absolute excess risks. The risk for developing breast cancer after Hodgkin's disease was greatest in women who were under the age of 25 at treatment. The most significant risk factor for the development of both leukemia and solid tumors was the combined use of radiation therapy and chemotherapy. The RR following RT alone was 4.1 (AR = 51.1); for RT + CT (initially or at relapse) the RR was 9.75 (P < 0.05, nonoverlapping confidence limits, AR = 123.9). Survival following development of a second malignancy was poor in patients with leukemia, gastrointestinal tumors, lung cancer, and sarcoma. Survival from other malignancies including NHL and breast cancer was more encouraging. Second malignant neoplasms are a major cause of late morbidity and mortality following treatment for Hodgkin's disease. The most significant risk factor for the development of second tumors is the extent of treatment for Hodgkin's disease. Recommendations are presented for both prevention and early detection of these tumors.  相似文献   
102.
103.

Background  

The WHO recommends that adults with uncomplicated P. falciparum successfully treated with a blood schizonticide receive a single dose of primaquine (PQ) 45 mg as a gametocytocidal agent. An earlier pilot study suggested that 75 mg of bulaquine (BQ), of which PQ is a major metabolite, may be a useful alternate to PQ.  相似文献   
104.
对于大多数胃食管反流病 (GERD)病人而言 ,治疗的主要目的在于控制症状和防止复发。而伴有糜烂性食管炎者 ,其主要目标则为愈合糜烂和 /或防止并发症。目前发现 ,大多数GERD病人 ,不论其内镜表现如何 ,短时间内使用抑酸药后 ,症状在 6个月内复发。要维持原来的疗效 ,确保糜烂愈合 ,用最小剂量质子泵抑制剂 (PPI)作维持治疗已是公认的较理想方法。当然长期维持治疗的选择也应顾及病人意愿。如果症状发作不频繁 ,那么按需治疗是一个合理的处理方案。事实上 ,病人也仅在症状复发时才会正规、持续地服药。对这类病人 ,以PPI作为按…  相似文献   
105.
The surface glycoprotein CD36 (GPIV) is known to mediate the adhesion of Plasmodium falciparum malaria-infected red blood cells and to be a receptor for extracellular matrix proteins such as collagen and thrombospondin. The murine monoclonal IgM antibody NL07, which is specific for CD36, has now been shown to also be a potent inhibitor of the adhesion of P falciparum malaria-infected red blood cells to C32 melanoma cells. Treatment of platelets with NL07 monoclonal antibody resulted in rapid degranulation, release of ATP and serotonin, increase in [Ca2+]i, and tyrosine phosphorylation of a substrate protein of 130 kD. In about one-half of the experiments, activation with NL07 resulted in the formation of small aggregates of 10 to 30 platelets, whereas in the other half of the experiments, large aggregates were seen similar to those induced by adenosine diphosphate (ADP) and these large aggregates could be converted to the small aggregates by ATP alpha S or by AP-2 or other antibodies against GPIIb and/or IIIa. Microaggregates of 2 to 5 platelets were seen with Glanzmann's platelets that constitutively lack GPIIb/IIIa. Aggregate formation was not seen with heat-treated serum, in the presence of anti C1q antibodies, or when using C5-, C8-, or C9-deficient human sera. Although activation of platelets with purified complement components results in a slow morphologic change without aggregation, involvement of CD36 results in rapid complement-mediated activation leading to formation of small aggregates that is largely independent of GPIIb/IIIa and that, under certain circumstances, proceeds to the formation of large ADP-dependent aggregates.  相似文献   
106.

Background  

Injecting drug use is a key risk factor, for several infections of public health importance, especially hepatitis B (HBV) and hepatitis C (HCV). In England and Wales, where less than 1% of the population are likely to be injecting drug users (IDUs), approximately 38% of laboratory reports of HBV, and 95% of HCV reports are attributed to injecting drug use.  相似文献   
107.
We have investigated whether the skin-homing T lymphocytes identified by the cutaneous lymphocyte antigen (CLA) are increased in the synovial membrane of patients with psoriatic arthritis. Twenty-six synovial samples (13 psoriatic arthritis, seven rheumatoid arthritis, six osteoarthritis) were obtained from involved knees. Lesional skin biopsies were taken from nine of the patients with psoriatic arthritis and six patients with psoriasis alone. All samples were single- and dual-stained for CLA and CD3 (to identify T lymphocytes) using HECA-452 (anti-CLA) and anti-CD3 monoclonal antibodies. E-selectin expression was also determined. The percentage of dual-stained lymphocytes was significantly greater in psoriatic skin than in synovium (P < 0.001) and similar between psoriatic and rheumatoid synovium. There was no significant difference in the percentages of CLA-positive cells in psoriatic skin in patients with psoriatic arthritis compared with psoriasis alone. The intensity of endothelial E-selectin expression was significantly greater in skin psoriasis than in synovium (P < 2 x 10(- 5)), and rheumatoid synovium had significantly greater expression than psoriatic synovium (P < 0.05). However, there was no significant correlation between E-selectin expression and the percentages of CLA- positive lymphocytes. This study provides further evidence that the CLA antigen is enriched on skin-homing lymphocytes. Conversely, the link between skin and joint inflammation in psoriatic arthritis does not seem to be explained by increased trafficking of CLA T cells to psoriatic synovium.   相似文献   
108.
109.

Background and purpose:

Limited data on the brain penetration of potential stroke treatments have been cited as a major weakness contributing to numerous failed clinical trials. Thus, we tested whether interleukin-1 receptor antagonist (IL-1RA), established as a potent inhibitor of brain injury in animals and currently in clinical development, reaches the brain via a clinically relevant administration route, in experimental stroke.

Experimental approach:

Male, Sprague-Dawley rats [either naïve or exposed to middle cerebral artery occlusion (MCAo)] were given a single s.c. dose of IL-1RA (100 mg·kg−1). The pharmacokinetic profile of IL-1RA was assessed in plasma and CSF up to 24 h post-administration. Brain tissue distribution of administered IL-1RA was assessed using immunohistochemistry. In a separate experiment, the neuroprotective effect of the single s.c. dose of IL-1RA in MCAo was assessed versus a placebo control group.

Key results:

A single s.c. dose of IL-1RA reduced damage caused by MCAo by 33%. This dose resulted in sustained, high concentrations in plasma and CSF, penetrated brain tissue exclusively in areas of blood–brain barrier breakdown and co-localized with morphologically viable neurones. CSF concentrations did not reflect massive parenchymal infiltration of IL-1RA in MCAo animals compared to naïve.

Conclusions and implications:

These data are the first to show that a potential treatment for stroke, IL-1RA, rapidly reaches salvageable brain tissue via an administration route that is clinically relevant. This allows confidence that IL-1RA, as a candidate for further clinical development, is able to confer its protective actions both peripherally and centrally.  相似文献   
110.
This review summarizes a series of experiments aimed at answering the question whether the hippocampus in rats can serve as an animal model of amnesia. It is recognized that a comparison of the functions of the rat hippocampus with human hippocampus is difficult, because of differences in methodology, differences in complexity of life experiences, and differences in the degree of hippocampal damage. Notwithstanding, rats and humans with hippocampal damage are similarly impaired on analogous tasks that assess spatial memory, spatial pattern separation, spatial configural and arbitrary associations, temporal order memory, temporal pattern separation, sequential learning, and temporal associations. These data suggest that the rat can serve as a model of memory dysfunction (amnesia) as it relates to spatial and temporal processing of new information.  相似文献   
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