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61.
Epidermal growth factor (EGF) is a potent growth factor for many tissues including the gastrointestinal tract. EGF is present in the gut lumen and is absorbed through the mucosa in the developing animals. In addition, EGF has been found to alter the immune system. In this study, we investigated thein vitro effect of EGF on normal colonic lamina propria lymphocyte DNA synthesis and ornithine decarboxylase activity. Human colonic lamina propria lymphocytes were isolated by collagenase-EDTA digestion. The effect of EGF on Con A-stimulated lymphocyte thymidine incorporation was tested. We observed that EGF suppressed DNA synthesis and ornithine decarboxylase (ODC) activity in lamina propria lymphocytes. EGF did not alter the time course of thymidine incorporation into LPL stimulated by the combination of phorbol 12,13-dibutyrate (PDB) and ionomycin. Our data suggest that (1) EGF suppresses DNA synthesis in human colonic lamina propria lymphocytes as well as ODC activity and (2) this inhibition may be mediated through protein kinase C or calcium flux. We postulate that EGF may have a role in modulating the human gut immune system.This work was supported in part by grant CA43280 from the National Institutes of Health.  相似文献   
62.

Introduction and aim

Operative fixation of distal radius fractures using fixed-angle devices has become increasingly common. Although good to excellent results have been reported in acute fractures, little is currently known regarding the fixation of healing displaced distal radius fractures that were presented late. The aim of this study was to evaluate the results of internal fixation of distal radius fractures presented late (>21 days) as compared with an acute-care control group.

Methods

Forty patients operated on for displaced distal radius fractures, presenting more than 21 days after injury (delayed treatment (DT) group), were compared with 75 age-matched controls with acute fracture repair (≤21 days). The same surgical approach was used in both groups, together with dorsal soft-tissue and brachioradialis release. No osteotomy was required. Direct and indirect reduction aids were used. A fixed-angle device (DVR; Biomet Inc., Warsaw, IN, USA) was used in both groups. Mean follow-up was 3.4 years. Quick DASH (Disabilities of the Arm, Shoulder and Hand) and Short Form 12 scores were used to evaluate outcome, as well as radiographic analysis for Arbeitsgemeinschaft für Osteosynthesefragen(AO)/Orthopaedic Trauma Association(OTA) classification, volar tilt, radial inclination and radial length.

Results

Average age was 53 years in both groups and male to female (M/F) ratio was similar in the study groups. Mean time to surgery was 30 days in the DT group and 8 days in the control group. There were significantly more type C (91.5% vs. 67.5%) fractures in the control group. The average quick DASH score was 27.1 in the DT group as compared with 6.3 in the control group (p < 0.03); however, when controlling for two outlier cases with complications (hardware irritation and a sensory neuropathy) there was no significant difference. Volar tilt, radial inclination and length were similar in both groups and were within normal anatomical values.

Conclusions

Delayed primary operative fixation of displaced unstable distal radial fractures is a viable option for cases that were presented late, with predictable, favourable results. Neither extensile approaches nor formal osteotomies are required.  相似文献   
63.
64.
Transthoracic parametric Doppler (TPD), unlike conventional ultrasonography, measures signals originating from movements of pulmonary blood vessel walls. In this pilot study, we tested TPD in 15 patients diagnosed with pulmonary embolism on computed tomography pulmonary angiography. Results were mapped to the upper, middle, and lower thirds of the right lung. In the lower third, TPD yielded 100% specificity and positive predictive value for acute pulmonary embolism. If validated in a larger series, this rapid bedside technique might obviate the need for computed tomography in specific cases. This could be advantageous in patients who are unstable, in intensive care, or have allergies to iodinated contrast material.  相似文献   
65.
Endometriosis is associated with an increased risk of ovarian cancer. Few studies have also shown increased risk of breast cancer. BRCA1/2 mutations are linked to an increased risk of breast and ovarian cancers but their relation to endometriosis is unknown.  相似文献   
66.
Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled immune activation and is traditionally associated with inherited gene defects or acquired causes. In addition to abnormalities in cytotoxic granules and lysosomes, various primary immune deficiency disorders (PID) have been identified among patients suffering from HLH. Our purpose was twofold: to better characterize and detail the association between PID and HLH.  相似文献   
67.
Gender-specific differences in the prevalence, incidence, comorbidities, prognosis, severity, risk factors, drug-related aspects and outcomes of various medical conditions are well documented. We present a literature review on the extent to which research in this field has developed over the years, and reveal gaps in gender-sensitive awareness between the clinical portrayal and the translation into gender-specific treatment regimens, guidelines and into gender-oriented preventive strategies and health policies. Subsequently, through the lens of gender, we describe these domains in detail for four selected medical conditions: Asthma, obesity and overweight, chronic kidney disease and coronavirus disease 2019. As some of the key gender differences become more apparent during adolescence, we focus on this developmental stage. Finally, we propose a model which is based on three influential issues: (1) Investigating gender-specific medical profiles of related health conditions, rather than a single disease; (2) The dynamics of gender disparities across developmental stages; and (3) An integrative approach which takes into account additional risk factors (ethnicity, socio-demographic variables, minorities, lifestyle habits etc.). Increasing the awareness of gender-specific medicine in daily practice and in tailored guidelines, already among adolescents, may reduce inequities, facilitate the prediction of future trends and properly address the characteristics and needs of certain subpopulations within each gender.  相似文献   
68.
69.
OBJECTIVES: To determine the safety of pedicle screw fixation in thoracic spine deformity correction. METHODS: One hundred twelve pedicle screws were surgically placed in 25 patients with degenerative, posttraumatic, and Scheuermann kyphosis and idiopathic and neuromuscular scoliosis. Screw position was evaluated using intraoperative and postoperative radiographs and thin-slice computed tomography. RESULTS: Of the total 112 thoracic pedicle screws that were inserted, 98 screws (87.5%) were fully contained within the cortical boundaries of the pedicle. When comparing proximal screws (T1-T8) with distal screws (T9-T12) and convex placed screws with concave ones, a statistically significant difference in screw placement was evident (P < 0.05). More misplaced screws were seen proximally and on the concave side. Of the 14 malpositioned screws, 2 (1.8%) demonstrated aortic abutment. There were no neurologic deficits, vascular injuries, or mechanical failures recorded. CONCLUSIONS: Placement of thoracic pedicle screws is both feasible and safe.  相似文献   
70.
The association between clinical coronary artery disease, cerebrovascular disease, and aortic atherosclerosis has not been examined in the general population. Transesophageal echocardiography was performed in 581 subjects, a random sample of the Olmsted County (Minnesota) population aged >/=45 years, participating in the Stroke Prevention: Assessment of Risk in a Community (SPARC) study. The frequency and severity of atherosclerosis of the thoracic aorta were determined in the population and the association between clinical coronary artery disease, cerebrovascular disease, and aortic atherosclerosis was examined. Previous myocardial infarction, angina pectoris, and coronary artery bypass surgery were significantly associated with aortic atherosclerosis, adjusting for age and gender (p 4-mm thick, ulcerated plaques, or mobile debris), adjusting for age and gender (p <0.05). Age, smoking, pulse pressure, previous myocardial infarction (odds ratio [OR] 4.67; 95% confidence interval [CI] 1.42 to 15.40), and coronary artery bypass surgery (OR 5.12; 95% CI 1.01 to 26.01) were independently associated with aortic atherosclerosis. Among subjects with atherosclerosis, age, smoking, pulse pressure, hypertension treatment, and coronary artery disease (OR 2.50; 95% CI 1.18 to 5.30) were independently associated with complex atherosclerosis. Weak associations were observed between previous ischemic stroke, transient ischemic attack, and aortic atherosclerosis, associations that were not significant after age- and gender-adjustment (p >0.2). Thus, coronary artery disease is strongly associated with aortic atherosclerosis and complex atherosclerosis in the general population. Cerebrovascular disease is weakly associated with aortic atherosclerosis, thereby questioning the overall importance of aortic atherosclerosis in the pathogenesis of cerebrovascular events in the general population.  相似文献   
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