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71.
Total lower abdominal wall resection was required to remove a recurrent exophytic bladder carcinoma in a 36-year-old woman. The resulting 25 x 30-cm fascial defect was repaired with Marlex mesh. Bilateral rectus femoris myocutaneous flaps were rotated to close the 25 x 18-cm area of skin deficiency. These provided the advantages of robust cover of the lower abdominal wall in a single-stage procedure and primary closure of the donor sites. 相似文献
72.
Rebecca J Sommer Adam J Hume Jessica M Ciak John J Vannostrand Megan Friggens Mary K Walker 《Toxicological sciences》2005,83(2):363-371
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase. 相似文献
73.
Cell proliferation in adult hippocampus is decreased by inescapable stress: reversal by fluoxetine treatment. 总被引:17,自引:0,他引:17
Adult hippocampal neurogenesis has been demonstrated in several species and is regulated by both environmental and pharmacological stimuli. The present study seeks to determine whether hippocampal proliferation and neurogenesis are altered in adult animals exposed to inescapable shock (IS) in the learned helplessness model of depression. We report that exposure to avoidance testing, regardless of pre-exposure to IS, decreases cell proliferation in the hippocampus, extending previous studies demonstrating downregulation of neurogenesis by exposure to acute stressors. In addition, when the analysis was conducted 9 days after exposure to IS we observed a significant decrease in cell proliferation compared to nonshocked animals. Administration of fluoxetine, a serotonin selective reuptake inhibitor, from days 2-8 blocked the downregulation of cell proliferation resulting from IS. Fluoxetine treatment also reversed the deficit in escape latency observed in animals exposed to IS. Finally, at the 9 day time point, there was no significant difference in blood levels of corticosterone between nonshocked and IS exposed animals, indicating that the decreased cell proliferation that is observed is not due to increased levels of this adrenal steroid. These findings demonstrate that exposure to IS, which results in a state of behavioral despair, decreases hippocampal cell proliferation and that this effect can be reversed by fluoxetine treatment. 相似文献
74.
Sensitization of striatal N-methyl-
-aspartate receptors (NMDAR) has been linked to events leading to the motor response changes associated with the administration of dopaminomimetics to parkinsonian animals and patients. To determine whether tyrosine phosphorylation of NMDAR subunits contributes to the apparent long-term enhancement in synaptic efficacy of these receptors, we examined the effect of unilateral nigrostriatal dopamine system ablation with 6-hydroxydopamine followed by twice-daily treatment with
-DOPA on the phosphorylation state of rat striatal NR2A and NR2B subunits. Three weeks of intermittent
-DOPA administration produced a shortening in the duration of the rotational response to dopaminergic challenge and other changes mimicking those occurring in patients with Parkinson's disease. Concurrently, tyrosine phosphorylation of NR2A and especially of NR2B subunits increased ipsilateral to the lesion (20±5% and 46±7% of intact striatum, respectively; p<0.01) without attendant changes in subunit protein levels. Selective blockade of NR2B subunits with ACEA 10-1244, but not of NR2A subunits with MDL 100,453, reversed the
-DOPA-induced response alterations. The intrastriatal injection of a tyrosine kinase inhibitor, genistein, at a dose (2.0 μg) that normalized the response shortening, attenuated the NR2A and NR2B phosphorylation increase by about 12% and 24%, respectively (p<0.01). Taken together, these results suggest that augmented tyrosine phosphorylation of NR2B subunits, alone or in combination with the smaller rise in NR2A subunit phosphorylation, contributes to the apparent enhancement in striatal NMDAR sensitivity and thus to the plastic alterations in dopaminergic responses in
-DOPA-treated parkinsonian rats. 相似文献
75.
Feng-Chun Tsai Daniel Marelli Jessica Bresson David Gjertson Reza Kermani Abbas Ardehali Fardad Esmailian Michele Hamilton Gregg C Fonarow Jaime Moriguchi Mark Plunkett Antoine Hage Julie Tran Jon A Kobashigawa Hillel Laks 《American journal of transplantation》2002,2(6):539-545
Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection. 相似文献
76.
77.
The purpose of this study is to develop a new vascularized epiphyseal plate model in the New Zealand White rabbit using a metatarsal epiphyseal plate having limited longitudinal growth potential. Such a model could be utilized in various experiments aimed at manipulating epiphyseal plate growth. The viability of the harvested live subject grafts was demonstrated with continued epiphyseal uptake during Tc99-MDP radionuclide bone scanning. The currently described models used in epiphyseal transplant research all involve long bone epiphyseal plates with significantly greater growth potential than the new metatarsal model. This new model therefore fills a void in the field by allowing investigators to transplant a growth plate with limited growth potential into any heterotopic site and study the effects of various hormonal and physical influences upon epiphyseal plate growth performance. © 1995 Wiley-Liss, Inc. 相似文献
78.
We conducted a prospective survey on the incidence of respiratory
complications associated with tracheal intubation and extubation in 1005
patients who underwent elective general anaesthesia over a 4-month period.
During induction of anaesthesia, respiratory complications occurred in 46
patients (4.6%; 95% confidence limits (CL): 3.3, 5.9%). The common
complications were coughing (1.5%) and difficult ventilation through a
facemask (1.4%). Tracheal intubation was difficult in eight patients
(0.8%). Complications occurred immediately after tracheal extubation in 127
patients (12.6%; 95% CL: 10.6, 14.7) and in the recovery room in 95
patients (9.5%; 95% CL: 7.6, 11.3%). The common complications immediately
after extubation were coughing (6.6%) and oxygen desaturation (SaO2 <
90%) (2.4%), and in the recovery room, airway obstruction (3.8%) and
coughing (3.1%). The incidence of complications was significantly higher
immediately after tracheal extubation than during induction of anaesthesia
(P << 0.001). Even when all incidents of coughing that occurred after
tracheal extubation were disregarded as a complication, the overall
incidence was still higher immediately after extubation (7.4%) than during
induction of anaesthesia (P < 0.01). We conclude that the incidence of
respiratory complications associated with tracheal extubation may be higher
than that during tracheal intubation.
相似文献
79.
Paul A. Demers Thomas L. Vaughan Thomas D. Koepsell Joseph L. Lyon G. Marie Swanson Raymond S. Greenberg Noel S. Weiss 《American journal of industrial medicine》1993,23(4):629-639
Lifetime job histories from a population-based, case-control study were analyzed to investigate the relationship between multiple myeloma and employment in various occupations and industries. Interviews were obtained from 89% (692) of eligible incident cases and 83% (1683) of eligible controls. An elevated risk was observed among persons ever employed as painters [odds ratio (OR) + 2.1, 95% confidence interval (CI) + 1.2–3.6], particularly for those employed for 10 or more years (OR + 4.1, 95% CI + 1.8–10.4). A small excess risk was observed among agricultural workers employed for 10 or more years (OR + 1.3, 95% CI + 1.0–2.2), with a higher relative risk observed among farm laborers (OR + 1.8, 95% CI + 1.0–4.0). Among agricultural workers who reported having been highly exposed to pesticides, the OR was 5.2 (95% CI + 1.6–21.1). Some evidence, based on smaller numbers, was also found to support an association with firefighting and employment in the petroleum- and coal-products manufacturing industries. Little evidence was found to support the previously noted association with wood exposure, and no evidence for an association with employment in the rubber or petroleum refining industries was found. This study lends further support to previously reported associations between multiple myeloma and employment among painters and agricultural workers. © 1993 Wiley-Liss, Inc. 相似文献
80.
This North Carolina case study addresses the migration of anesthesiologists into subspecialty, clinical areas of anesthesiology over a 4-year period (1984 to 1987). Three hundred fourteen members of the North Carolina Society of Anesthesiologists (NCSA) were surveyed using a one-page questionnaire. The response rate was 93.6%. The questionnaire elicited data to characterize the magnitude of change in anesthesiologist manpower, to assess emerging subspecialization, to describe the flux of anesthesiologists entering and leaving practice, and to detail evolving modes of practice. Results indicated a net increase in manpower averaging 8.8% per year in academic programs, whereas clinical community practitioners increased physician positions at a rate three times the former (27% increase per year). Of 184 anesthesiologists recruited to North Carolina over 4 years, 75 different residency programs were represented; 48% of new anesthesiologists were from southern educational programs and 44% entered practice with fellowships (i.e., postgraduate year 4 to 5). The principal fellowship was cardiac (33%). Subspecialty areas were represented in all 53 reporting clinical practices. The principal practice mode emerging was hospital-based, same day surgery (85%) followed by pediatric anesthesia (81%), perioperative pain management (68%), obstetric anesthesia (63%), and an anesthesia "clinic" (54%). Respondents expected additional practice options over the next 3 years with anesthesia for ambulatory diagnostic and therapeutic modalities projected to emerge at the fastest rate. In conclusion, anesthesiologists in North Carolina seem to be filling unmet needs in obstetric and cardiac anesthesia, critical care, ambulatory surgery, and pain therapy units. These observations may represent a vignette of the national scene. 相似文献