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21.
Lipoprotein (a) (Lp(a)) and other lipid values have been correlated with angiographically defined [table: see text] coronary artery disease. To study this relationship in Indian patients, plasma levels of Lipoprotein (a) and other lipids were assessed in 74 patients undergoing Coronary arteriography and also in 53 age and sex matched healthy male blood bank donors who served as controls. Total cholesterol (mg/dl) (211 +/- 56 vs 186 +/- 43; p < 0.001), low density lipoprotein Cholesterol (mg/dl) (117 +/- 40 vs 88 +/- 29; p > 0.001) and low density lipoprotein/high density lipoprotein cholesterol ratio (2.6 +/- 0.8 vs 2.2 +/- 0.9; p < .001) were significantly higher in patients than controls. High density lipoprotein-cholesterol (mg/dl) (43.5 +/- 6 vs 42.1 +/- 7; p-ns) very low density lipoprotein-cholesterol (mg/dl) (49.7 +/- 17 vs 56.1 +/- 25; p-ns) and triglycerides (mg/dl) (155 +/- 101 vs 167 +/- 88; p-ns) were not statistically different in two groups. Lipoprotein (a) levels showed highly skewed distribution. Patients (n = 74) showed almost five fold higher lipoprotein (a) levels (mg/dl) as compared to controls (n = 53) [105 +/- 565 vs 23 +/- 76]. Patients with very high lipoprotein (a) levels [values of more than 40 mg/dl] (n = 18) had high density lipoprotein cholesterol and total cholesterol significantly lower than rest of the patient group. [high density lipoprotein cholesterol (mg/dl) 41.00 +/- 3.7 vs 44 +/- 6.4; p < 0.01 and total cholesterol (mg/dl) 192 +/- 34 vs 217 +/- 53; p < 0.05].  相似文献   
22.
One hundred and forty eight subjects with euthyroid solitary thyroid nodules (STN) were taken up for radionuclide perfusion study. They were found to have a cold STN on 99mTc thyroid static scan. All had fine needle aspiration cytology (FNAC), and except for subjects with chronic lymphocytic thyroiditis, were subjected to surgery for tissue diagnosis by histopathology. The diagnostic findings in these patients of solitary thyroid nodules were correlated with the histopathology. Radionuclide perfusion study is considered useful to differentiate benign from malignant cold thyroid solitary nodules with high degree of sensitivity (95%) and specificity (87.9%).  相似文献   
23.
The middle cranial fossa approach: an anatomical study   总被引:1,自引:0,他引:1  
Chopra R  Fergie N  Mehta D  Liew L 《Surgical and radiologic anatomy : SRA》2003,24(6):348-51; discussion 352-3
Hearing preservation surgery has become an option for an increasing number of patients with vestibular schwannomas due to diagnosis at an earlier stage. The middle cranial fossa approach represents one such surgical approach for resection of vestibular schwannomas with hearing preservation. We have undertaken an anatomical study of the middle cranial fossa approach to the internal auditory meatus using 20 fresh temporal bones. By simulating the surgical approach it was possible to analyze critically two of the main recognized subapproaches to the internal acoustic meatus. The results confirmed that the angle subtended by the facial nerve and "blue-lined" semicircular canal was much less than 60 degrees but equally important was the degree of individual variability. Furthermore the roof of the geniculate fossa was not infrequently dehiscent. The distance measured from the inner table of the craniotomy to the superior semicircular canal was on average 22 mm, similar to previous reports and utilized by some in their approach in this challenging surgery. From this anatomical study it appears that safe dissection of this area is facilitated by observing the more acute angle between the facial nerve and superior semicircular canal and by taking advantage of the relationship between the inner table and important landmarks.  相似文献   
24.
Phorbol myristate acetage (PMA) and Ca2+ ionophore A23187 mimic early signal transduction pathways and activate purified human T cells to secrete large quantities of interleukin-2 (IL-2) and to proliferate. Despite producing 50-100-fold more IL-2 than phytohaemagglutinin (PHA)-activated peripheral blood lymphocytes (PBL), PMA/A23187-stimulated human T cells proliferate less than cells activated by PHA. Washing the cells to remove PMA/A23187 was found to increase cellular proliferation two to five-fold. High-affinity IL-2R (HA-IL-2R) were found to be expressed by human T cells that had been washed 24 hr after PMA/A23187 stimulation and recultured without stimulus for an additional 48 hr, but not by T cells constantly exposed to PMA/A23187 for 72 hr. Radioligand binding studies with [125I]IL-2 demonstrated that while the alpha (p55) and beta (p70-75) subunits of HA-IL-2R were both present on the constant PMA/A23187-stimulated T cells, they did not appear to associate to form functional HA-IL-2R. This defect in the expression of bio-active HA-IL-2R on constant PMA/A23187-stimulated human T cells seems to account for their low proliferative response.  相似文献   
25.
This study examined the relative impact of different self-reward strategies on maintenance of breast self-examination (BSE) practice among 1649 women trained to do BSE. Training groups were randomized into four conditions: (a) self-reward instructions and materials delivered at the end of the BSE training session; (b) self-reward suggestions delivered through the mail each month, contingent upon the BSE performance; (c) external monetary rewards and self-reward suggestions delivered through the mail each month on an intermittent schedule, contingent upon BSE practice; and (d) a no-reward control condition. Follow-up assessments 12 months following training revealed a pattern of evidence in support of the benefits of external monetary rewards and self-reward prompts on BSE frequency and quality; however, it is likely that the value of that condition lies in the external reward component.  相似文献   
26.
The mechanism of cholera toxin (CT)-stimulated arachidonate metabolism was evaluated. CT caused rapid in vitro synthesis of prostaglandin E2 (PGE2) in murine smooth muscle-like cells (BC3H1), reaching maximal levels within 3 to 4 min. In comparison, cyclic AMP (cAMP) levels were unchanged, and addition of dibutyryl cAMP did not affect PGE2 synthesis. CT-induced PGE2 synthesis was prevented by actinomycin D or cycloheximide, indicating a need for de novo protein synthesis. Northern blot analysis of total RNA from BC3H1 cells revealed that exposure to CT resulted in an increase in abundance of mRNA encoding phospholipase A2 (PLA2)-activating protein (PLAP). PLAP is a regulatory protein that increases the enzymatic activity of cellular PLA(2), which in turn causes increased hydrolysis of arachidonate from membrane phospholipids. Furthermore, CT evoked the accumulation of PLAP mRNA in J774 (murine monocyte/macrophage) and Caco-2 (human intestinal epithelial) cells in vitro, but the responses were more delayed than that of BC3H1 cells. A protein band of approximately 35 kDa, which corresponded to the size of PLAP, was observed in sodium dodecyl sulfate extracts of Caco-2 cells by Western blot (immunoblot) analysis using affinity-purified antibodies to PLAP synthetic peptides. Synthesis of PLAP protein was increased after 2 h of exposure to CT. Exposure of mouse intestinal loops to either CT or live Salmonella typhimurium for 3 h increased mucosal PLAP mRNA levels. The role of PLAP in CT-induced PGE2 synthesis provides an attractive explanation for the reported suppression of CT-induced intestinal secretion by inhibitors of protein synthesis.  相似文献   
27.
28.
The effect of exercise training prior to acute myocardial infarction (AMI) on left ventricular (LV) remodeling is poorly understood. This study investigated the protective effect of 3 weeks of swimming exercise training prior to AMI on cardiac morphology and function. Male Sprague-Dawley rats (n = 35) were randomly assigned to 3 groups: swimming training (n = 14, 90 min, 5 days/wk, 3 wk), sedentary (n =14), and controls (n = 7, no exercise, no MI). At the end of the training/sedentary period, rats were subjected to AMI (ExMI and SedMI) induced by surgical ligation of the left coronary artery. Thereafter, the rats remained sedentary for a 4-wk recovery period. Trans-thoracic echocardiography was performed in each group at the end of the exercise/sedentary period (pre-AMI), 24 hr after AMI, and following recovery (4 wk after AMI). No differences were observed in LV dimensions and function pre-AMI among the 3 groups; however, LV-end systolic diameter (LVESD) and LV-end systolic area (LVES-area) were significantly lower in the prior trained rats, 24 hr post-AMI with no additional change 4 wk post-AMI, during remodeling. Both LV-shortening fraction (SF%) and fractional area change (FAC%) were higher in the trained animals 4 wk post-AMI (39+/-12% vs 23+/-8%; p 0.002, and 48+/-14% vs. 38+/-9%; p 0.07, respectively). In conclusion, 3 wk of swimming exercise training prior to AMI significantly attenuated LV remodeling and improved LV function, despite no changes in LV dimensions or systolic function at the end of the exercise session. The data suggest that even a short-term training period is sufficient to induce cardiac protection.  相似文献   
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30.
In cases of obscure gastrointestinal bleeding, when a source for blood loss is not apparent from examination of the colon and upper gastrointestinal tract, the small bowel usually becomes the focus of investigation. A tumor with interesting pathologic features was found in a patient who presented with recurrent episodes of massive obscure gastrointestinal hemorrhage. This case highlights the importance of considering small intestinal tumors as the likely cause of obscure gastrointestinal hemorrhage in young patients and how a noninvasive test, eg, abdominal computed tomography scan, might obviate the need for more invasive testing.  相似文献   
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