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61.
Using a corticostriatal slice preparation, we have recently shown that tetanic stimulation of the corticostriatal pathway produces long-term depression (LTD) of striatal excitatory synaptic transmission. In the present study we have analysed the relationship between LTD and the striatal release of different endogenous transmitters. Samples of perfusate were collected via a small cannula placed just above the surface of the striatal slice close to the recording electrode, and were analysed by HPLC. The high-frequency stimulation (100 Hz, three trains, 3 s duration, 20 s intervals) used to induce LTD caused a significant but transient increase in the release of both excitatory (aspartate and glutamate) and inhibitory (glycine and GABA) amino acid transmitters. Tetanic stimulation also produced a significant, but transient increase in the release of endogenous dopamine. We conclude that the tetanic stimulation of the corticostriatal pathway is able to induce a large but transient release of excitatory amino acids and of dopamine, whose participation in the induction of striatal LTD has been demonstrated previously. Moreover, the maintenance of this form of synaptic plasticity does not seem to require a sustained change in transmitter release.  相似文献   
62.
OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ2 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.)  相似文献   
63.
We describe a patient with neonatal Marfan syndrome presenting with massive ascending and descending thoracic aortic aneurysm. Because of rapidly progressive respiratory distress due to tracheobronchial compression, emergency replacement of the descending thoracic aorta with a 12-mm PTFE vascular prosthesis was undertaken at 1 month of age. The postoperative course was complicated by bilateral tension pneumothorax contributing to irreversible respiratory failure. The unique clinico-pathological features and the relevant surgical implications of the case are discussed. (J Card Surg 1994;9:109–114)  相似文献   
64.
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient.  相似文献   
65.
To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD.  相似文献   
66.
PURPOSE: The purpose of this study was to identify the risk factors for severe discomfort after mandibular third molar surgery and to assess the validity of the Postoperative Symptom Severity (PoSSe) scale. PATIENTS AND METHODS: In a 2-year prospective study, a total of 255 unilateral impacted mandibular third molar teeth were surgically removed under local anesthesia by 3 surgeons. Standardized surgical and analgesic protocols were followed. At the review appointment, 1 week after surgery, all patients returned a completed follow-up questionnaire (PoSSe scale) and were evaluated clinically for postoperative pain (number of painkillers taken) and trismus (differences in mouth opening). Sixteen predictive variables were evaluated using stepwise logistic regression analysis to identify the risk factors associated with severe discomfort. RESULTS: Severe postoperative discomfort was predicted by these independent variables: gender, tobacco use, ramus relationship/space available, and antibiotic prophylaxis. Oral contraceptive use and operation time were not identified as risk factors. The patients' perceptions of the severity of symptoms (PoSSe scale score) was strongly correlated with clinical assessment of trismus (r = 0.54) and pain (r = 0.42). CONCLUSION: The PoSSe scale resulted in a valid and responsive measure of the severity of symptoms after surgical extraction of lower third molars and reflected the clinical severity of the postoperative discomfort. From a patient's perspective, operative factors had little bearing on the quality of life after removal of mandibular third molars.  相似文献   
67.
Two young brothers were bilaterally affected by pigmentary glaucoma and extensive symmetrical changes of the retinal pigment epithelium (RPE). Fundus changes consisted in widespread salt-and-pepper RPE mottling and pigment clumping, sparing only the peripapillary and foveal areas. During the course of 4 years, one of the two patients suffered multiple, recurrent, exudative and hemorrhagic detachments of the RPE that involved the midperiphery and posterior pole. No exudative lesions appeared in the brother. The medical history and systemic laboratory tests were noncontributory in both patients. The ERG was normal and the EOG subnormal. Dark adaptation was delayed and showed an elevation of the scotopic threshold. These cases seem to support the hypothesis that the RPE is also involved in the pigmentary dispersion syndrome. An inherited defect could affect the pigment epithelium in both the anterior and posterior segments of the eye. The multifocal subretinal exudative pattern that occurred in one of our patients has not been previously observed in hereditary disorders of the RPE.Presented at the XVIth Meeting of the Club Jules Gonin, Bruges, 4–8 September 1988  相似文献   
68.
Body art in the form of tattoos and piercing has become increasingly popular amongst children and teenagers, and is nowadays more socially acceptable despite media reports citing tissue destruction and death. Our study explored the awareness and experience of patients with congenital heart disease, and of cardiologists and professionals responsible for their care.  相似文献   
69.
Haemophilia A: molecular insights.   总被引:1,自引:0,他引:1  
Haemophilia A is the most common inherited bleeding disorder caused by defects in the F8C gene that encodes coagulation factor VIII. This X-linked recessive disorder occurs in approximately 1:5000 males. Haemophilia A is diagnosed based on normal prothrombin time, altered activated partial thromboplastin time and reduced factor VIII activity in plasma. Carrier females are usually asymptomatic and can be identified only by molecular analysis. The most frequent mutations in F8C are intron 22 and 1 inversions, which occur in approximately 50% and 5% of patients, respectively, with a severe phenotype. Large gene deletions are observed in approximately 5% of alleles from patients with severe haemophilia A. The remaining severe cases and all moderate and mild cases result from numerous point mutations and small insertions/deletions, which are de novo mutations in one-third of cases. Thus, molecular diagnosis of carrier status and prenatal diagnosis in families without intron 22 or 1 inversions is based on scanning techniques or gene sequencing. When the disease-causing mutation cannot be identified, molecular diagnosis is performed by linkage analysis of several DNA polymorphic markers linked to F8C. Given the clinical heterogeneity among haemophilic patients, many groups, including our own, have examined the relationships between prothrombotic gene variants and haemophilic phenotype to investigate whether prothrombotic gene variants modify clinical expression of the disease.  相似文献   
70.
PURPOSE: This study examined the association between maternal smoking before and during the first trimester of pregnancy and spontaneous abortion.

METHODS: We have been conducting a hospital-based case-control study on risk factors for spontaneous abortion in the greater Milan area. We collected information from 782 cases of spontaneous abortions and 1543 controls (women who delivered at term healthy infants).

RESULTS: With respect to never smokers, the odds ratio (OR) were 0.7 (95%, confidence interval (CI), 0.5–1.0) for women who quit smoking and 1.3 (95% CI, 1.0–1.6) for those who continued during pregnancy. Women who smoked more than 10 cigarettes/day in the first trimester were at increased risk of miscarriage, with an OR of 1.4 (95% CI, 1.0–2.1). No relationship was evident between the number of cigarettes smoked before conception and the risk of abortion. Likewise, no association emerged between paternal smoking and miscarriage. Moreover, no significant interaction or modification effect was obtained when strata of age and other major characteristics were investigated.

CONCLUSIONS: The risk of abortion associated with cigarette smoking during the first trimester of pregnancy was measurable and noticeable in this population, and accounted for 9% (95% CI, 6–13%) of all cases. The increased risk of spontaneous abortion in women smoking during pregnancy is a further reason to encourage pregnant women to quit.  相似文献   

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