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991.
Background. Variation at the apolipoprotein E (apo E) locus influence lipid and lipoprotein levels in the normal population, and is associated with premature coronary artery disease. Patients with end-stage kidney disease or undergoing dialysis treatment are particularly prone to develop accelerated atherosclerosis. Methods. To evaluate the influence of genetic variation at the apo E locus, apo E genotypes and serum lipid and lipoprotein levels were measured in 51 subjects undergoing continuous ambulatory peritoneal dialysis (CAPD). Results. The distribution of apo E phenotypes and apo E allelic frequency among the CAPD subjects (&egr;2 0.049; &egr;3 0.745; &egr;4 0.206) corresponded to the healthy Swedish population. In the CAPD subjects, total serum and LDL cholesterol levels were high (6.7±1.5 mmol/l and 4.2±1.3 mmol/l respectively) and HDL cholesterol levels were low (1.2±0.5 mmol/l). When directly comparing the two major apo E groups, E 3/3 subjects (n=30) and E4/3 and 4/4 subjects, &egr;4-carriers, (n=16), LDL cholesterol levels were significantly higher among &egr;4-carriers (4,8±1.1 vs 4.0±1.2 mmol/l, P<0.03), but total serum cholesterol levels was not higher among the &egr;4-carriers (7.3±1.3 vs 6.5±1.5 mmol/l, P<0.08). Serum triglycerides or HDL cholesterol levels did not differ significantly between &agr;3-homozygotes and &egr;4-carriers. Conclusions. The results demonstrate a strong effect of variation of the apo E locus on LDL cholesterol levels in CAPD subjects, suggesting that &egr;4-carriers may be more susceptible to accelerated development of atherosclerosis in this condition.  相似文献   
992.
A 32–year–old man had an unusual gunshot wound to the leg, causing a peroneal nerve palsy. Sonography provided useful complementary findings to the electrodiagnostic localization of the injury.  相似文献   
993.
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506, have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients). CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7 pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury of the liver graft, possibly by modulating effects of TNF-α.  相似文献   
994.
OBJECTIVE: To determine the course of events during the onset of hyperprolactinemic amenorrhea, a nonhuman primate model was sought that did not require suckling or interference with the in situ hypothalamic-pituitary axis. DESIGN: Because removal of the adenohypophysis from hypothalamic influence results in secretion of large quantities of prolactin (PRL) but little of the other adenohypophyseal hormones, we explored the possibility of establishing pituitary allografts in monkeys. Normally cycling female rhesus monkeys were immunosuppressed with a daily regimen of cyclosporin A (CyA; 10 to 15 mg/kg per day) and then subcutaneously grafted with a pituitary from another animal (allograft). Blood samples were obtained daily via saphenous vein puncture during control, only CyA-treatment, and allografted-plus CyA- menstrual cycles. SETTING: Oregon Regional Primate Research Center, Beaverton, Oregon. PARTICIPANTS: Female Macaca mulatta exhibiting regular menstruation. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Prolactin, luteinizing hormone (LH), estradiol (E2), and progesterone (P) levels were determined in harvested serum. RESULTS: Temporary survival of 5 of 11 (45%) allografts was assumed based on elevations in serum PRL. Of the viable grafts, 4 of 5 (80%) resulted in reproductive dysfunction, as first evidenced by delay or loss of the preovulatory rise in E2. When the peak of follicular E2 was delayed, then the LH surge occurred, but it was also delayed. If follicular E2 levels did not peak, then the LH surge was absent as was luteal P production. CONCLUSION: These data suggest that in the etiology of PRL-induced infertility in women, the first event is a suppression of follicular E2 production. In addition, the hypothalamus probably remains responsive to the positive feedback of E2 during early or moderate hyperprolactinemia.  相似文献   
995.
996.
Urinary excretion of cross-linked N-telopeptide of type I collagen (NTx) has been reported to be a specific marker of bone resorption [18]. We assessed a new immunoassay for NTx as an indicator of changes in bone resorption caused by spontaneous menopause and compared cross-sectionally the levels of urinary NTx, hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), hydroxyproline (OH-Pr), other serum biochemical indices, and lumbar spine and proximal femur bone mineral density (BMD). Eighty-one Japanese women aged 22–77 participated in this study; 36 were premenopausal and 45 were postmenopausal. Urinary HP, LP, and NTx stayed at low levels in the premenopausal period and rose 21%, 30%, and 67% in the postmenopausal period, respectively. The rise in LP and NTx was statistically significant (P < 0.01), suggesting that NTx is mostly released from bone matrix when bone resorption is accelerated. When premenopausal women were divided into two age groups and postmenopausal women were divided into two groups according to years since menopause (YSM) there were significant differences in LP and NTx between women <4 YSM and women aged <40 and those women aged 41+ (P < 0.01 and P < 0.05, respectively). A significant 110% increase in urinary NTx and a 48% increase in urinary LP were observed in postmenopausal women compared with age-matched premenopausal women aged 45–55. All biochemical markers other than serum PTH correlated significantly with each other (r = 0.243–0.858, P < 0.05–0.0001). Urinary NTx inversely correlated with lumbar spine BMD. When postmenopausal women were divided into three groups, the correlation between bone resorption and formation markers in women 0-1 YSM was greater than in women 2–10 YSM and in women 11 + YSM, indicating that resorption and formation are coupled at the early postmenopausal period. We conclude that urinary NTx is responsive to changes in bone metabolism caused by estrogen deficiency and may be a more sensitive and specific marker than HP, LP, or OH-Pr in the early postmenopausal years. Received: 15 February 1995 / Accepted: 18 October 1996  相似文献   
997.
Objective. Rapidly destructive hip disease (RDHD) is an uncommon disorder of the hip that has been considered a disease of unknown cause and distinct from ischemic necrosis of the femoral head. The objective of this study was to investigate ischemic necrosis of the femoral head as one potential cause of RDHD. Design and patients. In 600 patients who underwent MR imaging of the hip, 20 cases of ischemic necrosis involving the entire femoral head in 18 patients (3%) were retrospectively studied with routine radiography and MR imaging. All patients had surgically confirmed ischemic necrosis of the femoral head. Results and conclusions. All patients showed rapid destruction of the femoral head on routine radiography and MR imaging as compared with the gradual onset of clinical symptoms. Plain radiographs showed several bone fragments at the inferomedial aspect of the femoral head (75%), acetabular erosions (55%), eccentric depression at the lateral articular surface of the femoral head conforming to the adjacent acetabulum (35%), and mild osteoarthritis (15%). Bone sclerosis was often present at sites of impaction between the femoral head and the acetabulum. MR imaging showed marked distention of the joint capsule in all cases. In 14 of 20 cases, the contents of the joint space showed predominantly low or intermediate signal intensity on T1- and T2-weighted images. Ischemic necrosis involving the entire femoral head may represent one of the causes of RDHD.  相似文献   
998.
999.
The phenotype in the rd mouse is similar to the clinical presentation of Leber congenital amaurosis (LCA) in humans. Recently a nonsense mutation in the beta subunit of the cGMP phosphodiesterase (Pdeb) gene has been defined as the cause for the rd phenotype in the mouse and has raised the question as to whether mutations in the human PDEB gene might cause LCA. We have previously cloned and characterized the human homologue of the mouse Pdeb gene and have mapped it to chromosome 4p16.3. In this study, a total of 23 LCA families of various ethnic backgrounds have been investigated. Linkage analysis using highly polymorphic (CA)n microsatellites has excluded the PDEB gene as a cause for LCA in 6 families. In the remaining 17 families, we have searched for mutations in the 22 exons of the PDEB gene using single-strand gel electrophoresis (SSGE). Multiple exonic polymorphisms have been determined. However, no DNA changes in the PDEB gene have been identified in our study population which could be causative for the LCA phenotype.  相似文献   
1000.
The proliferative activity of gastric adenomas from 18 patients (42 endoscopic procedures) was compared with follow-up results. These cases were gastric adenomas proven by follow-up with repeated endoscopic procedures for more than 2 years, or were confirmed as gastric adenocarcinoma thereafter by histopathologic examination. Among the eighteen cases, nine showed carcinoma in the subsequent biopsies (group 1) and the remaining nine did not result in carcinoma (group 2). The proliferating cell nuclear antigen (PCNA) positivity rates of the two groups were significantly different (P < 0.01). The average PCNA positivity in group 1 was 33.1%, while it was 10.0% in group 2. The risk of developing carcinoma increased as the PCNA positivity increased: 0% in the low PCNA positivity group, 41% in the mid-positivity group and 89% in the high positivity group. We concluded that growth fraction could be taken into account as one of the most important prognostic factors for gastric adenoma, and accordingly repeated endoscopic biopsies with close follow-up should be carried out especially in the high PCNA positivity group.  相似文献   
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