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The expression of surface tissue factor procoagulant activity and its shedding by blood monocytes can be induced by several stimuli. Few of these defined situations, other than the presence of bacteria and their toxins, are commonly present in the young human infant. In this study, measurements were made of the percentage of monocytes expressing surface tissue factor apoprotein (TFA) in blood taken from babies in the early weeks of life. Mononuclear cells were separated from blood in an environment free of detectable endotoxin. After exposure to a polyclonal rabbit antibody raised to purified brain TFA and subsequent exposure to a fluorescin-labeled murine anti-rabbit IgG, the cell fluorescent activity was analyzed by flow cytometry. The percentage of monocytes showing strong fluorescence was determined. In every instance when systemic bacterial infection was present, more than 60% of the monocytes examined showed fluorescence indicative of the presence of surface TFA. In a single case of fungal Candida septicemia, none of the monocytes was positive. More than 60% of cells were found to be positive in certain instances where infection was highly probable but not proven. Positive cells were found in three cases of isoimmune hemolytic disease of the newborn, as had been anticipated from previous studies, whereas less than 25% of monocytes derived from babies in the absence of discernible infection or isoimmune hemolytic disease expressed surface TFA (p less than 0.001). These findings provide insight into a possible mechanism of coagulation activation in sepsis and may prove to be a useful predictor of the presence of infection or endotoxemia in young infants.  相似文献   
3.

Background  

Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.  相似文献   
4.
Segel  MC; Paulus  DD; Hortobagyi  GN 《Radiology》1988,169(1):49-54
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer.  相似文献   
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Donor insemination (DI) using cryopreserved semen commenced at The Royal Women's Hospital in 1976. Over the next 15 years we performed 5953 treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live births. In-vitro fertilization (IVF) using donor spermatozoa commenced in 1986. Over the next 5 years we performed 303 treatment cycles for 185 couples. Including subsequent transfer of cryopreserved embryos, a total of 33% of couples achieved a successful pregnancy by IVF. Statistical analysis indicated that, for DI pregnancies, the most important semen variable was the percentage post-thaw motility, whilst for normal fertilization in IVF it was the pre-freeze motility. These results may be explained by the compensatory effects of post-thaw processing of spermatozoa for IVF, but not for DI in our clinic.   相似文献   
7.
Cattermole TJ 《Injury》1999,30(7):491-495
A retrospective analysis of all skiing injuries experienced by members of the British Antarctic Survey between 1989 and 1995 was undertaken to test the hypothesis that skiing was responsible for a disproportionate number and severity of injuries compared with other activities. Fifty-nine new consultations for skiing injuries were recorded. This represented 3.2% of all consultations (annual range 1.3-6.7%), or 9.7% of all consultations due to trauma. The mean incidence was 84.3/1000 population/year. The annual proportion and rate of consultation fluctuated but no overall trends were noted. The lower limb was the commonest site of injury (76.3%), with the ratio of lower limb: upper limb injuries being 6.4:1. The commonest single injury was an isolated medial collateral ligament knee sprain (23.7% of all consultations). Head injuries comprised 8.5% and ulnar collateral ligament thumb sprains 5.1%. Assessment of injury by the Injury Severity Score (ISS) showed that skiing injuries were significantly more likely to be non-trivial (ISS > 2) than work-related injuries [chi 2(1, N = 56) = 55.6, p < 0.001] or injuries of all causes [chi 2(1, N = 56) = 65.0, p < 0.001]. They were significantly more likely to need radiological investigation than all injuries [chi 2(1, N = 59) = 22.0, p < 0.001]. The most severe (ISS 13), survivable injury seen during the study period resulted from a skiing accident. This excess of non-trivial injury raises important management issues, particularly as the majority (81%) were recreational.  相似文献   
8.

Objective

Patients with chronic obstructive pulmonary disease (COPD) present systemic inflammation. Strenuous resistive breathing induces systemic inflammation in healthy subjects. We hypothesized that the increased respiratory load that characterizes COPD can contribute to systemic inflammation in these patients.

Patients and methods

To test this hypothesis, we compared leukocyte numbers and levels of circulating cytokines (tumor necrosis factor alpha [TNFα], interleukin-1β [IL-1β], IL-6, IL-8, and IL-10), before and 1 hour after maximal incremental inspiratory loading in 13 patients with stable COPD (forced expiratory volume in one second [FEV1] 29 ± 2.5% ref) and in 8 healthy sedentary subjects (FEV1 98 ± 5% ref).

Results

We found that: (1) at baseline, patients with COPD showed higher leukocyte counts and IL-8 levels than controls (p < 0.01); and, (2) one hour after maximal inspiratory loading these values were unchanged, except for IL-10, which increased in controls (p < 0.05) but not in patients with COPD.

Conclusions

This study confirms the presence of systemic inflammation in COPD, shows that maximal inspiratory loading does not increase the levels of pro-inflammatory cytokines (IL-1β, IL-8) in COPD patients or controls, but suggests that the former may be unable to mount an appropriate systemic anti-inflammatory response to exercise.  相似文献   
9.
ObjectiveTo determine the prevalence of Trichomonas vaginalis (T. vaginalis) in HIV/AIDS patients attending two different hospitals in southeast Nigeria.MethodsWe collected 970 urine samples from HIV/AIDS patients attending two different hospitals in southeast Nigeria. Samples were processed by microscopy and cultural methods.ResultsOut of the 970 screened, 355 (36.60%) were positive for T. vaginalis. Subjects with the least CD4+ count in the range of 40-140 cells/mL had the highest number of positive samples (180, 50.70%), while those in the range of 480-580 cells/mL had the least value (2, 0.56%). Those in the rural areas had a higher number of positive samples (155, 38.75%) than their urban counterparts (200, 35.09%) with respect to the total number examined in each group but this was not statistically significant (P>0.05). Out of the 355 positive cases, the university undergraduate students’ group had the highest percentage incidence of 53.00% followed by the low-income group with 47.08%.ConclusionsIt can be concluded that the occurrence of T. vaginalis increases with decrease in the CD4+ counts in HIV/AIDS patients in Nigeria. Since T. vaginalis may be an important cofactor in promoting the spread of HIV and, in some circumstances, may have a major impact on the epidemic dynamics of HIV, there is a need to take measures to check the spread of this parasitic infection.  相似文献   
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