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51.
Thrombogenesis in the left atrial appendage (LAA) has been related to the special morphology of this cavity and to its size and degree of dysfunction. However, no study has focused on LAA function in conjunction with left atrial (LA) function in both sinus rhythm (SR) and nonrheumatic idiopathic atrial fibrillation (AF) in relation to clinical status (cardioembolic stroke). Forty-three patients in SR (14 patients with stroke, 29 control subjects) and 45 patients in AF (27 patients with stroke, 18 control subjects) were examined by transthoracic and transesophageal echocardiography. Baseline clinical characteristics and standard transthoracic and transesophageal measurements of the LA and LAA (size, fractional area change, flow measurements, spontaneous echo contrast, and thrombus) were recorded and compared in relation to cardiac rhythm. Patients in the stroke-SR group showed a significant decrease of fractional area change in the LA (32%+/-15%) and LAA (34%+/-15%) in relation to control subjects (43%+/-10%, p = 0.035, 49%+/-13%, p = 0.006, respectively). Patients in the stroke-AF group showed significant reduction of appendage flow measurements (outward velocity = 22+/-13 vs 33+/-19 cm/sec, p = 0.036), whereas no differences were detected in the center of the LA. In multiple regression analysis, the presence of cardioembolic stroke was positively associated with the presence of spontaneous echo contrast (p = 0.0253) and spontaneous echo contrast negatively associated with appendage inward flow velocity (p<0.001). Cardioembolic stroke in patients in SR is associated with a global decrease of shortening in both cavities and in patients with AF, with a reduction of LAA flow parameters. Patients with spontaneous echo contrast, thrombus, or both showed further reduction of shortening and flow velocities in both cavities, indicating a more advanced stage of dysfunction.  相似文献   
52.
The nature of the physiological stimulus inducing decidualization in the endometrium is unknown. In this study we attempted to verify a recent report that relaxin can induce decidualization in intact mice primed with a high dose of estradiol valerate (5 micrograms) and a low dose (10 micrograms) of medroxyprogesterone acetate. In our study, neither s.c. nor intrauterine relaxin, nor intraluminal arachis oil, (an established deciduogenic stimulus) were able to induce decidualization. In addition, while oil was able to induce decidualization (increased uterine weight, and positive Pontamine Sky Blue and stromal alkaline phosphatase reactions) in ovariectomized mice treated with a regimen of estradiol and medroxyprogesterone acetate designed to produce optimum uterine sensitivity, no decidualization occurred in response to either s.c. or intraluminal relaxin. This study fails to provide any support for a role for relaxin as a deciduogenic stimulus.  相似文献   
53.
The development of a new diffusion cell for in vitro transdermal permeation is described. The so-called Kelder cells were used in combination with the ASPEC system (Automatic Sample Preparation with Extraction Columns), which is designed for the automation of solid-extractions (SPE). Instead of SPE columns, 20 Kelder cells were placed in the racks. This allowed automatic sampling of up to 20 cells for 24 h in a dynamic mode. The cells consist of an inlet compartment, a donor compartment and a receptor compartment. The size and the depth of the inlet compartment were important to avoid entrapment of air bubbles in the receptor compartment. The Kelder cells mimic blood flow beneath the skin by replacement of the permeating drug every 2 min. Hence sink condition are more easily maintained than with the static Franz diffusion cell. The performance of the cells was tested with permeation experiments using atropine as a model drug permeating through an artificial membrane (Silastic). The use of this skin model minimized the variability in permeation of atropine as compared with human skin.  相似文献   
54.
55.
Two generations of outcome research demonstrate the potential efficacy of marital therapy in the treatment of depression. After reviewing treatment outcome studies on marital therapy for depression, we examine basic research linking aspects of the marital relationship to depressive symptoms. In doing so, we highlight a number of theoretical perspectives and research findings that can inform work with couples in which one spouse is depressed. Finally, we identify potential innovations that may lead to a third generation of marital interventions for depression and several avenues of inquiry for a third generation of outcome research on marital therapy for depression.  相似文献   
56.
Malignant tumors are known to exhibit high rates of glycolytic activity leading to high production of lactic acid. Hence, neoplastic cells have elevated activity of enzymes responsible for glycolysis. Echitamine chloride, an indole alkaloid extracted from the bark of Alstonia scholaris, has been reported to have a highly promising anticancer activity against fibrosarcoma in rats. In the present study, the effect of echitamine chloride on energy metabolism of S-180 cells is investigated to have a better understanding on the mode of action of echitamine chloride. The effect of echitamine chloride on the mitochondrial and cellular respiration of S-180 cells was studied. Also, the effects on glucose utilization, pyruvate utilization and lactate formation were studied on whole S-180 cells and S-180 cell-free homogenate. The levels of glycolytic enzymes such as hexokinase and lactate dehydrogenase were estimated in which particular emphasis has been laid on hexokinase which occurs both in cytosolic and particulate forms in neoplastic cells. Hence the differential effect of echitamine chloride on the levels of total, cytosolic and particulate hexokinase has been investigated. In conclusion, echitamine chloride affects both cellular and mitochondrial respiration, leading to reduction of the cellular energy pool and thereby resulting in the loss of viability of S-180 cells.  相似文献   
57.
BACKGROUND AND PURPOSE: The aim of our study was to characterize the patient profile and prognostic value associated with high positive IgG (>100 GPL) anticardiolipin antibodies (aCL). METHODS: We studied the clinical, laboratory, radiological, and prospective historical features of ischemic cerebrovascular disease in patients with >100 GPL titers. From our neurology department, 27 consecutive patients were prospectively identified and followed up (mean follow-up time, 34 months). RESULTS: The mean age of our cohort was 41 years. Lupuslike illness occurred in 3; 23 had primary antiphospholipid syndrome, including 3 who met criteria for Sneddon's syndrome; 1 patient had progressive systemic sclerosis. Cerebral infarcts occurred in 74% and were recurrent in 37%. Systemic ischemic events, most commonly deep vein thrombosis, occurred in 37%. Tobacco use was documented in 85%, hyperlipidemia in 74%, hypertension in 44%, and diabetes mellitus in 7% of patients. A prominent headache history was present in 67%. Lupus anticoagulant (LA) was present in 72%, approximately one half had positive antinuclear antibodies and thrombocytopenia, and one quarter had a false-positive VDRL. We compared mean GPL levels in patients testing positive for specific laboratory features of antiphospholipid syndrome with those testing negative for these parameters. Only the LA(+) group had a significantly higher mean GPL than the LA(-) group (P=0.006). Brain imaging showed nonlacunar infarcts in 73% and lacunes in 12%. Of 19 cerebral angiograms, 5 (26%) showed large-vessel occlusive disease and 6 (32%) branch obstruction. Echocardiograms were abnormal in 75%: thickened left-sided valves in 33% and vegetations in 12%. Recurrent cerebrovascular ischemic events were observed in 96%, with transient events (mean rate, 25%/y) occurring 5 times more frequently than strokes (mean rate, 5%/y). Using a standardized disability scale blinded to aCL titer, neurological impairment was severe in 7%, moderate in 30%, and mild or nonexistent in 63%, and unrelated to mean GPL value (P=0.567). Titers fluctuated greatly for individual patients, and most did not consistently test as highly positive. An analysis of fluctuation in symptom severity with concurrent GPL values did not show a statistically significant correlation. Compared with historical controls having a wide range of positive titers, the presence of high IgG aCL titers did not confer a worse prognosis for disability and recurrent ischemic events. CONCLUSIONS: Our data suggest that cerebrovascular events associated with high positive GPL are frequently multiple and minor (with no disability-titer correlation), present in relatively young patients, and often associated with tobacco abuse, hyperlipidemia, LA, systemic ischemic events, and occult cardiac disease.  相似文献   
58.
The effects of surgical repair versus non-repair on cell morphology and type X collagen expression were investigated using a rat model of Achilles tendon avulsion. The animals were divided into four groups. In Group 1, tendon was reattached to the original attachment site by suturing through a drill hole in the calcaneus; in Group II, tendon was not reattached and a drill hole was not made; in Group III, tendon was not reattached but a drill hole was made; and the animals in Group IV were sham operated. In Group I (tendon reattached), at 2 weeks postoperatively, many hypertrophic chondrocytes appeared at the reattachment site adjacent to bone and type X collagen was detected immunologically both in the cells and in the extracellular matrix. After 4 weeks, the cells at the original site of attachment were arranged in rows along the newly formed tendon fibers and were stained with type X collagen antibody. By contrast, when tendon was not reattached (Groups II and III), a gap between the original attachment site and the tendon stump was observed through the entire postoperative period. At 8 weeks, the original attachment site was covered by fibrocartilaginous tissue and tendon became attached to the calcaneal fibrocartilage area, which is proximal to the original attachment site. Type X collagen was detected in the cells which were adjacent to bone. In Group IV (sham operation), there were no changes in histology or type X collagen distribution, either at the attachment site or in tendon and bone, compared with the non-operated control rats. These results suggest that surgical reattachment of tendon to the original site is important to help reorganize cells during the repair process. Type X collagen was identified immunohistochemically in the cells adjacent to bone in all the groups, suggesting that it may play a role in maintaining distinct areas of calcified and non-calcified fibrocartilage.  相似文献   
59.
For six weeks, recipient (Lewis RT11) and donor rats (LBNF11/n) were fed three diets that varied only in their lipid content. Diet A (MO) contained 19.5% menhaden oil and 0.5% safflower oil and was rich in omega 3 PUFA; diet B (SO) was 20% safflower oil rich in omega 6 PUFA; and diet C (BT) was 20% beef tallow rich in omega 9 monounsaturated fatty acids and saturated fat. In the first set of graft survival studies a group fed laboratory chow was included (CHOW). Heterotopic cardiac transplantation from donor to recipient animals was performed after the six-week feeding period. The effect of these diets on cardiac allograft survival, mixed lymphocyte response, and blood flow in the rejecting grafts was investigated. The median graft survival in days was significantly prolonged in the rats maintained on either MO (12 days) or SO (14.5 days) compared with the BT (8 days)-or lab chow (7.5 days)-fed animals (P < 0.05). Cyclosporine (CsA) administered at subtherapeutic levels further increased the differences between the PUFA-fed animals and the BT-fed group. The myocardial blood flow of the rejecting allografts was measured using an 85Sr-labeled microsphere technique on the fifth posttransplant day. Flow was greatest in the MO-fed group, and both MO and SO groups had significantly higher myocardial blood flow than BT-fed rats (P < 0.05) or those bearing isografts. The allogenic mixed lymphocyte responses of peripheral blood mononuclear cells (PBMC) and splenic lymphocytes were suppressed in MO- and SO-fed groups compared with BT-fed animals. The immunosuppressive effect of dietary PUFA warrants further investigation, and their use as a possible adjunctive treatment in organ transplantation should be considered.  相似文献   
60.
The catecholamines norepinephrine (NE) and dopamine (DA) have been implicated in the sexual differentiation of brain and behavior and in species-specific learning in several species. To determine if these neurotransmitters might be involved in sexual differentiation of the vocal control system and song learning in male zebra finches, NE and DA levels and turnover rates were quantified in 10 behaviorally relevant brain nuclei [6 vocal control (VCN), 2 auditory (AN), and 2 hypothalamic (HN)] at four critical points during sexual differentiation of the VCN and the period of song learning, 25, 35, 55, and 90 days of age. Some birds were pretreated with alpha-methyl-para-tyrosine (alphaMPT) to allow estimation of NE and DA turnover rates. NE and DA levels in microdissected nuclei were quantified using high-performance liquid chromatography with electrochemical detection. AlphaMPT treatment suppressed catecholamine synthesis just as effectively in juveniles as it does in adults and proved an effective method for estimating NE and DA turnover rates. Patterns of NE and DA function in most VCN and AN over development were quite different from those in HN in which NE and DA function changed gradually and showed no striking peaks. NE turnover rates changed significantly over development in all six VCN [nucleus interfacialis (Nlf), high vocal center (HVC), nucleus robustus of the archistriatum (RA), dorsomedial portion of the intercollicular nucleus (DM), Area X of the parolfactory lobe, and lateral portion of the magnocellular nucleus of the anterior neostriatum (IMAN)]; one AN [nucleus mesencephalicus lateralis pars dorsalis (MLd)], and one HN [preopticus anterior (POA)]. NE levels changed significantly in two VCN (Nlf and Area X). In Nlf, RA, Area X, IMAN, and MLd, NE levels and/or turnover rates showed a striking peak at day 25, which was not seen in HN. Both DA levels and turnover rates changed profoundly over development in 5 of 6 VCN (Nlf, RA, DM, Area X, and IMAN) and both AN (MLd and Field L). These nuclei showed striking peaks in DA levels and turnover rates, primarily on day 35 and/or 55, which then declined profoundly by day 90. This contrasted with the minimal change in DA turnover rates seen in one HN (POA) and the sixth VCN, HVC. In several VCN and AN, NE and DA levels and turnover rates during development reached levels never seen in adult males. Previous research has shown that catecholamine function is heightened in VCN during development compared to surrounding tissues. Our data demonstrate that NE and DA function during development shows pronounced peaks in most VCN not seen in HN. This is interesting because both VCN and HN are hormone sensitive, and both show hormone-modulated NE and DA function in adult males. The timing of these peaks suggests that increased catecholaminergic function may be involved in sexual differentiation of the VCN and song learning in finches.  相似文献   
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