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1.
Retinal arterial macroaneurysms   总被引:5,自引:0,他引:5  
Retinal arterial macroaneurysms represent a distinct clinical entity. Macroaneurysms are seen in the elderly with a marked female predominance and a strong association with hypertension and arteriosclerotic vascular changes. The classic appearance provides an easy diagnosis; however, variable presentations, such as subretinal hemorrhage, macular exudate, and epiretinal membranes can make the diagnosis difficult. The differential diagnosis of retinal arterial macroaneurysms include retinal telangiectasia, angiomatosis retinae, venous macroaneurysms, background diabetic retinopathy, and cavernous hemangioma. The clinical characteristics of the reported cases are summarized, and our series of 60 patients is presented. The natural history of most macroaneurysms is spontaneous involution without loss of vision. However, visual loss may occur secondary to macular edema, exudate, hemorrhage and neurosensory retinal detachment, and photocoagulation may expedite visual recovery. Photocoagulation treatment may be applied directly to the macroaneurysm, indirectly by surrounding the macroaneurysm, or as a combination of these two methods.  相似文献   
2.
In this study, we report the complete cDNA sequence, genomic organization and expression pattern of the Caenorhabditis elegans ClC chloride channel gene, clh-6. Two different types of reporter gene fusions suggest that clh-6 expression is restricted to two gamma-aminobutyric acid-ergic RME neurons. These results are in striking contrast with the wide tissue distribution of messenger RNA for the related mammalian isoforms, CIC-6 and CIC-7. The restricted expression pattern of clh-6 provides a unique opportunity to study the biological function of a neuronal CIC chloride channel.  相似文献   
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There are cases in which resection of cervico-mediastinal goitres requires additional thoracic access as an adjunct to standard transverse cervicotomy, and typically this takes the form of sternotomy or thoracotomy. The authors propose transclavicular access as an alternative to thoracotomy or sternotomy access for the removal of such goitres. This technical variant is performed by means of resection of the middle third of the clavicle and extraperiosteal disarticulation. They report a case of cervicomediastinal or "plunged" goitre associated with mediastinal metastasis from a follicular thyroid carcinoma in a 77-year-old woman, in whom this technical variant was used. They conclude by stressing the greater effectiveness, ease of execution and relatively limited "aggressiveness" of the technique in comparison with other ways of reaching the mediastinum. The variant proves effective in solving a number of technical, functional and aesthetic problems.  相似文献   
5.
Environmental stressors can substantially affect the adaptive response of rats to novelty in a sexually dimorphic manner. Gender-related differences are also observed in neurochemical and behavioural patterns of adult rats following prenatal exposure to diazepam (DZ). In the present study the behavioural reactivity to novelty is investigated in open field (OF) and in acoustic startle reflex (ASR) tests, in non handled (NH), short-lasting handled (SLH) and long-lasting handled (LLH) adult male and female rats prenatally exposed to DZ. A single daily s.c. injection of DZ (1.5 mg/kg) over gestation days 14-20 decreases GABA/BDZ receptor function in both sexes, as shown by the decreased electrographic hippocampal response to DZ and the increased response to picrotoxin, after intra-locus coeruleus injection of the two compounds. In OF NH DZ-exposed males display a lower total distance travelled (TDT), a higher rearing frequency (RF) and a greater number of transitions in the centre of the arena (CNT) compared to NH rats prenatally exposed to vehicle. Conversely, NH DZ-exposed females show slight changes in TDT and RF and a greater reduction in CNT and in the amount of time spent in the centre of the arena (CAT). These effects are associated with an increase in the peak amplitude of the ASR in both sexes. Short-lasting handling slightly influences DZ-evoked effects in animals of both sexes. In DZ-exposed males long-lasting handling attenuates the reduction in TDT and the enhancement in RF, prevents the increase in CNT and reduces the peak amplitude of ASR. In DZ-exposed females, long-lasting handling increases TDT and RF, induces a lower avoidance of the centre of the arena, and does not modify the peak amplitude of ASR, when compared to controls. These findings indicate that prenatal exposure to DZ differently affects behavioural reactivity in adult male and female rats, and suggest that a long-lasting handling is able to attenuate some behavioural deficits induced by prenatal DZ exposure.  相似文献   
6.
In thyroid surgery, an emergency tracheostomy is mandatory, as is well known, in acute pre- and postoperative asphyxia due to obstruction of the upper airways, especially in cases of malignant tumours. In particular conditions, in the presence of benign thyroid disease and when there is no reduction in the laryngo-tracheal lumen, tracheostomy has an important precautionary function following total thyroidectomy. The authors describe their experience with 6 patients treated by precautionary tracheostomy after total thyroidectomy for benign thyroid disease, analysing the indications and the advantages of this method.  相似文献   
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INTRODUCTION: Because the disparity between the number of patients waiting for kidney transplants and the number of available cadaveric renal allografts continues to increase, there is a clear need to review the inclusion criteria for cadaveric donors. PATIENTS AND METHODS: From January 2001 to March 2004, 24 patients with end-stage renal disease and hepatitis C virus (HCV) seropositivity underwent a kidney transplantation. In 10 transplants in HCV-positive recipients, the donor was HCV-positive (D+/R+) and in 14 cases the donor (1 living donor) was HCV-negative (D-/R+). RESULTS: Two of 3 HCV-RNA-negative recipients who received a HCV-RNA+ kidney became HCV-RNA+ in the posttransplantation period. There was a low rate of acute rejection (8.3%). One D+/R+ patient experienced an acute vascular rejection, which finally resulted in graft loss, due to the resurgence of severe infectious disease. The serum creatinine levels at 6 months posttransplantation were similar in both groups. Acute liver dysfunction was observed in 1 patient. There was no death in the entire series. Graft survival was 92% and 90% for D+/R+ and D-/R+, respectively.  相似文献   
9.
The authors report a simple chart that offers a comprehensive picture of spasticity of the upper limb and provides a more objective method of recording data. Distinction is made between fixed postures and the residual active range of motion at the shoulder and elbow. The presence and function of the muscles can be identified easily on dynamic EMG studies, which are essential for understanding the degree of spasticity and dyssynergy related to a single muscle. When spasticity of the upper arm is managed with a global approach and objectives are defined clearly in advance with the patient and caregivers, treatment of shoulder and elbow deformities can achieve important results for personal hygiene or functional targets.  相似文献   
10.
Serum and erythrocyte levels of the polyamines spermine, spermidine and putrescine, as well as ornithine decarboxylase in erythrocytes, were studied in patients with different neoplasms (breast, lung and colon cancer) and in those with a nonmalignant proliferative disease (familial polyposis). The blood levels of polyamines and the spermine/putrescine ratio were significantly higher in all tumors and in nonmalignant colon polyposis. In erythrocyte ornithine decarboxylase activity, spermine and spermidine levels, as well as spermidine/putrescine and spermine/putrescine ratios showed a significant decrease after surgery and chemotherapy. Our data suggest that high levels of blood polyamines and erythrocyte ornithine decarboxylase activity are related to cell proliferation and cancer treatment, but that levels of polyamines in serum and erythrocytes are still significantly high after cancer treatment and are similar to those in polyposis disease. Polyamines are related to nuclear activity during differentiation; therefore, the altered turnover of polyamines could be a sign of abnormal nuclear function. Since polyamines stimulate protooncogene expression, their high levels could be considered an important cofactor in malignant cell transformation.  相似文献   
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