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71.
72.
Two rare cases of intracranial meningeal melanocytoma are reported with clinical, radiologic, and pathologic findings. In one of these the diagnosis was established by ultrastructural studies that showed premelanosomes and melanosomes in nonarachnoid-derived tumor cells. The other case was diagnosed retrospectively after a very long survival and is still alive 35 years after total excision and radiotherapy. The occurrence of these tumors in the cerebellopontine angle is rare as seen in our case.  相似文献   
73.
Extracellular single neuron activity was recorded in the dorsolateral prefrontal cortex (DL) during bar pressing for food reward. Most of the reward-related neurons were located around the rostral end of the principal sulcus. Neuronal activity was diminished, abolished, or reversed when quinine adulterated food (aversive food) was given as a reinforcement. Cue-related neurons tended to be located more caudally in the DL. The activity of these neurons was not modulated by the nature of the reward as much as that of the reward-related neurons. The results suggest that DL neurons are not functionally homogeneous.  相似文献   
74.
Recent research has indicated that the malaria burden in Asia may have been vastly underestimated. We conducted a prospective community-based study in an impoverished urban site in Kolkata, India, to estimate the burden of malaria and typhoid fever and to identify risk factors for these diseases. In a population of 60452 people, 3605 fever episodes were detected over a 12-month period. The blood films of 93 febrile patients contained Plasmodium (90 P. vivax, 2 P. falciparum and 1 P. malariae). Blood cultures from 95 patients grew Salmonella enterica serotype Typhi. Malaria patients were found to be significantly older (mean age 29 years) compared with patients with typhoid fever (15 years; P<0.001) but had similar clinical features on presentation. Having a household member with malaria, illiteracy, low household income and living in a structure not built of bricks were associated with an increased risk for malaria. Having a household member with typhoid fever and poor hygiene were associated with typhoid fever. A geographic analysis of the spatial distribution of malaria and typhoid fever cases detected high-risk neighbourhoods for each disease. Focal interventions to minimise human-vector contact and improved personal hygiene and targeted vaccination campaigns could help to prevent malaria and typhoid fever in this site.  相似文献   
75.
Laparoscopic duodenojejunostomy for superior mesenteric artery syndrome   总被引:1,自引:0,他引:1  
Superior mesenteric artery syndrome (Wilkie's syndrome) causes acute or chronic compression of the third part of the duodenum. Initially conservative treatment is tried, but on failure of treatment, duodenojejunostomy is the procedure of choice, usually done by open surgery. We present a case of superior mesenteric artery syndrome in which the duodenojejunostomy was done laparoscopically.  相似文献   
76.
Despite the advances in minimally invasive surgery in children, considerable concern exists about employing such techniques in oncologic cases. We report our experience with a 4-year-old girl with a symptomatic tumor in the liver. Contrast-enhanced computed tomography revealed a 3 x 4 cm lesion, confined to segments II and III. Tumor markers were negative and true-cut needle biopsy did not rule out malignancy. We performed a diagnostic laparoscopy using four 5-mm ports. Since the tumor did not cause any alterations of the liver surface, a 5-mm flexible endoscopic ultrasound probe (5 MHz) was applied to reveal the extent of the tumor. Parenchymal dissection was performed with a radiofrequency probe, and the LigaSure device was used to seal larger vessels and bile ducts. The tumor was resected completely and removed in a specimen bag via the umbilical incision. Histology revealed fibrous nodular hyperplasia. The postoperative course was uneventful and the girl was discharged on postoperative day 5. We conclude that laparoscopic resection of confined liver lesions is feasible in children, employing standard principles of oncologic surgery and safety.  相似文献   
77.
78.
Multiple epiphyseal separation in battered baby syndrome is a rare occurrence. We report epiphyseal separations of proximal tibia and distal humerus along with femoral shaft fracture in a child of two and half years of age. In the course of clinical, laboratory, and radiological examinations, the child was diagnosed to be a case of battered baby syndrome. The child was treated and isolated from the mother, who was the culprit for battering the child. We believe, in any epiphyseal injury below 3 years of age, particularly when the distal humerus physis is involved, diagnosis of child abuse should be considered as an etiology.  相似文献   
79.
Second malignancies, mostly in the form of bone sarcomas, are known to occur in hereditary retinoblastomas, which usually present with bilateral disease. Only 2 cases of Ewing’s sarcoma have been reported in the literature following sporadic unilateral retinoblastoma. A 5-year-old boy presented to our hospital with Ewing’s sarcoma of the right humerus (proven by biopsy and immunohistochemistry) following successful treatment of retinoblastoma of the left eye with enucleation and chemotherapy 2 years previously. He was treated with 2 cycles of chemotherapy followed by radiation therapy. At 15 months follow-up, the tumor had reduced in size and the child had a good functional outcome. The cumulative risk of second malignancies in retinoblastoma survivors is 32%. Ninety-eight percent of second malignancies occur in patients with bilateral retinoblastoma. Germ line mutations have been considered in sporadic tumors occurring bilaterally and multifocal unilateral sporadic tumors. Bone and soft tissue sarcomas are the most common second malignancies. Radiation therapy increases the risk of developing a second malignancy in the irradiated field. Unilateral retinoblastomas, which comprise the majority of retinoblastomas, are not immune from the development of second malignancies. Close follow-up of all retinoblastomas—even in the early period—can improve the outcome by facilitating the early detection and aggressive treatment of second malignancies.  相似文献   
80.
Purpose: To report a case of peripheral ulcerative keratitis and central vein occlusion as the initial manifestation of HIV infection. Method: Case report. Result: A 46-year-old male presented with history of pain, redness, and diminished vision of left eye. Examination revealed left eye peripheral ulcerative keratitis (PUK) and right eye central retinal vein occlusion (CRVO). The patient was found to be positive for HIV on serological evaluation. Conclusion: Atypical ophthalmic manifestations may be the initial presenting feature in patients with HIV infection. This highlights the need for increased index of suspicion for HIV infection in young patients with PUK and/or CRVO.  相似文献   
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