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71.
Congenital pulmonary atresia with ventricular septal defect: angiographic and surgical correlates 总被引:1,自引:0,他引:1
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries. 相似文献
72.
Time of appearance during development of differences in nigrostriatal tyrosine hydroxylase activity in two inbred mouse strains 总被引:1,自引:0,他引:1
The greater activity of tyrosine hydroxylase (TH) in substantia nigra and corpus striata of adult BALB/cJ than CBA/J mice, is attributable to differences in the number of dopamine neurons in the ventral midbrain tegmentum. To determine if strain differences in TH activity develop postnatally we have measured the development of TH in the midbrain (SN) and in the corpus striatum (CS). In the midbrain neonatal TH activity was 20% of adult levels. Thereafter, TH activity increased rapidly achieving adult levels by 11 days. A 25% "overshoot' above adult values at 15 days was followed by a gradual decrease to adult activity at 4 weeks. In the CS neonatal activity was about 10% of adult levels and increased slowly to reach adult values at 4 weeks. Striatal choline acetyltransferase (CAT) activity in the neonate was only 3.7% of adult values and at 21 days had only reached 70% of adult activity. Neonatal glutamic acid decarboxylase (GAD) activity was relatively high in both brain regions and increased gradually to adult activity by 4 weeks. Strain differences in TH activity were not present at birth but first appeared at 9 days in SN and 11 days in CS. Once established, the differences were maintained. These results suggest that strain differences in TH are most probably a consequence of differences in postnatal neuron survival, although the possibility that some neurons lose their phenotypic expression of TH cannot be excluded. 相似文献
73.
Waleska Teixeira Caiaffa Francisco Incio Bastos Fernando Augusto Proietti ngela Cristina Maia Reis Sueli Aparecida Mingoti Denise Gandolfi Denise Doneda AjUDE-Brasil II Project 《The International journal on drug policy》2003,14(5-6):365
The study describes practices relating to syringe acquisition and disposal by Syringe Exchange Programme (SEP) participants. A cross-sectional multi-city study enrolled 857 injection drug users (IDUs) from six SEPs in different Brazilian regions, and assessed self-reported acquisition and disposal behaviours. Seven hundred and nine males (82.9%) and 146 females (17.1%) were recruited through outreach and interviewed, most from the streets or their neighbourhoods (54.1%). The average age was 28.5 years; 76.4% reported injecting cocaine in the past 6 months. Sources for acquiring new syringes differed significantly between time of injection drug use debut and the 6 months prior to interview. Fifty-three percent of IDUs reported acquiring their syringes in pharmacies when they initiated injection drug use, whereas most reported acquiring new syringes in the 6 months before interview from several simultaneous sources: 69% through SEPs; 58% through pharmacies; 36% from friends and/or sexual partners; and 17% from other health services. Across SEPs, acquisition and disposal varied widely. Most interviewees discarded their syringes on the streets, in open fields, or in the garbage or sewage. Restrictions on syringe availability and unsafe practices may be functioning as barriers to the public health recommendation of one-time use of sterile syringes for IDUs and discouraging community support to SEPs. Further increase in access to legal, inexpensive and timely sterile syringes, as well as counselling about the merits of one-time use and safer disposal must be reinforced as part of efforts to minimise high-risk behaviours and curb the spread of blood-borne infections. 相似文献
74.
Accelerated flap prefabrication with vascular endothelial growth factor 总被引:28,自引:0,他引:28
Li QF Reis ED Zhang WX Silver L Fallon JT Weinberg H 《Journal of reconstructive microsurgery》2000,16(1):45-49
Vascular endothelial growth factor (VEGF) is a potent promoter of angiogenesis that has been shown to enhance revascularization of ischemic tissues, including skin flaps. This study was designed to investigate the value of a single topical application of recombinant human VEGF to accelerate flap viability in a rat model of a non-ischemic prefabricated flap. Prefabricated flaps were created in 48 Sprague-Dawley rats. An autologous tail artery loop was anastomosed to the femoral artery and vein, and implanted subcutaneously in the lower abdomen. Flaps were divided into two groups of 24 each. At the time of loop implantation the control group received 0.9 percent NaCl or a 16 percent vol/wet polyvinyl alcohol (PVA) solution: the treatment group received VEGF in 0.9 percent NaCl or VEGF in PVA. The PVA gel was used to facilitate topical application In each group, 3- x 4-cm flaps nurtured by the tail artery pedicle were elevated and resutured into place after 3, 4, and 5 weeks. The percentage of surviving skin of each flap was determined by planimetry 7 days after flap elevation. Mean skin survival areas at 3, 4, and 5 weeks were control group 0 percent. 8 percent and 17.5 percent; and VEGIF-treated group, 6 percent, 40 percent, and 66.7 percent respectively VEGF significantly improved flap survival by 5 weeks (p = 0.02). These results suggest that VEGF can accelerate maturation of prefabricated flaps. This approach could expand the application of flap prefabrication as a resource for reconstructive surgery. 相似文献
75.
Transdermal nitroglycerine enhances spinal neostigmine postoperative analgesia following gynecological surgery 总被引:4,自引:0,他引:4
BACKGROUND: Intrathecal neostigmine causes analgesia by inhibiting the breakdown of acetylcholine. Experimental data suggest that the production of endogenous nitric oxide is necessary for tonic cholinergic inhibition of spinal pain transmission. The purpose of this study was to determine whether association of transdermal nitroglycerine would enhance analgesia from a low dose of intrathecal neostigmine in patients undergoing gynecologic surgery during spinal anesthesia. METHODS: Forty-eight patients were randomized to one of four groups. Patients were premedicated with use of 0.05-0.1 mg/kg intravenous midazolam and received 15 mg bupivacaine plus 1 ml test drug intrathecally (saline or neostigmine, 5 microgram). Twenty to 30 min after the spinal puncture, a transdermal patch of either 5 mg nitroglycerin or placebo was applied. The control (Con) group received spinal saline and transdermal placebo. The neostigmine group received spinal neostigmine and transdermal placebo. The nitroglycerin group received spinal saline and a transdermal nitroglycerine patch. Finally, the neostigmine-nitroglycerin group received spinal neostigmine and transdermal nitroglycerine. Pain and adverse effects were evaluated using a 10-cm visual analog scale. RESULTS: Patients in the groups were similar regarding age, weight, height, and American Society of Anesthesiologists status. Sensory level to pin prick at 10 min, surgical duration, anesthetic duration, and visual analog scale score for pain at the time of administration of first rescue medication were statistically the same for all groups. The time to administration of first rescue analgesic (min) was longer in the neostigmine-nitroglycerin group (550 min; range, 458-1,440 min; median, 25-75th percentile) compared with the other groups (P < 0.001). The neostigmine-nitroglycerin group required fewer rescue analgesics in 24 h than did the control group (P < 0.0005), whereas the neostigmine group required less analgesics compared with the control group (P < 0.02). The incidence of perioperative adverse effects (nausea, vomiting, headache, back pain) was similar among groups (P > 0.05). CONCLUSION: Although neither intrathecal 5 microgram neostigmine alone nor transdermal nitroglycerine alone (5 mg/day) delayed the time to administration of first rescue analgesics, the combination of both provided an average of 14 h of effective postoperative analgesia after vaginoplasty, suggesting that transdermal nitroglycerin and the central cholinergic agent neostigmine may enhance each other's antinociceptive effects at the dose studied. 相似文献
76.
77.
Ana Teresa Martins Luis Faísca Francisco Esteves Cláudia Simo Mariline Gomes Justo Angélica Muresan Alexandra Reis 《中国神经再生研究》2012,7(2):101-108
Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 ageand education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions. 相似文献
78.
79.
Izabela Guimarães Barbosa Natália Pessoa Rocha Aline Silva de Miranda Rodrigo Barreto Huguet Moisés Evandro Bauer Helton José Reis Antônio Lúcio Teixeira 《Revista brasileira de psiquiatria (S?o Paulo, Brazil : 1999)》2013,35(1):67-69
IntroductionBipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD.ObjectiveThe aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls.Methods87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA.ResultsOn average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications.ConclusionsThe present study suggests that long-term BD patients exhibit increased circulating levels of BDNF. 相似文献
80.
Fernanda Rodrigues Helmo Juliana Reis Machado Camila Souza de Oliveira Guimar?es Vicente de Paula Antunes Teixeira Marlene Ant?nia dos Reis Rosana Rosa Miranda Corrêa 《Disease markers》2013,35(6):939-944
Fetal skin has the intrinsic capacity for wound healing, which is not correlated with the intrauterine environment. This intrinsic ability requires biochemical signals, which start at the cellular level and lead to secretion of transforming factors and expression of receptors, and specific markers that promote wound healing without scar formation. The mechanisms and molecular pathways of wound healing still need to be elucidated to achieve a complete understanding of this remodeling system. The aim of this paper is to discuss the main biomarkers involved in fetal skin wound healing as well as their respective mechanisms of action. 相似文献