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101.
102.
The fine structure of the nuclear zone of neonatal mouse lenses can vary considerably according to the fixation used. When normal neonatal mouse lenses are fixed in a commonly used chilled glutaraldehyde solution, the nuclear zone develops a grossly visible opacity, and irregular sized protein granules appear in the subsequent sections. Similar artifacts of aggregated irregular sized protein granules appear when cataractous mouse lens are conventionally processed. These artifacts can be avoided by soaking the lens in 0.15 M reduced glutathione solution for 10-15 min before fixation in a phosphate buffered 2% glutaraldehyde solution (pH 7.4) at 27-35 C. Normal lenses treated in this manner maintain translucency in the nuclear zone throughout the fixation-embedding procedure, and the resulting sections show finely uniform granularity with the cell membrane well preserved. Similarly processed nuclear portions of cataractous lenses of Nakano mice show uniformly aggregated protein granules, measuring about 350A in diameter. The cell membranes in the cataractous zone are also not interrupted.  相似文献   
103.
Breast-conserving therapy must be carefully indicated amongpatients with Paget's disease of the breast, because the diseaseis often associated with an underlying in situ or invasive carcinoma,even when there are no palpable mass or mammography findings.We report a 52-year-old woman who complained of skin color changeof her right nipple for 11 months. No mass was palpable in herbreasts, and mammography did not show any density or calcification.Nipple biopsy revealed Paget's disease of the breast with ductalcarcinoma in situ (DCIS) in the breast epithelium just beneaththe nipple. Magnetic resonance imaging (MRI) of the breast demonstrateddiffuse segmental enhancement in two different quadrants. Accordingto the pattern of enhancement, the lesions depicted by MRI werediagnosed as an extensively spreading type of DCIS. Based oninformed consent, the patient received a total mastectomy. Thehistopathological examination demonstrated non-invasive ductalcarcinoma with comedo-necrosis. The histological mapping withsubserial sectioning demonstrated an extent of the lesions thatcorresponded accurately to the lesions defined by MRI. We concludethat MRI may play an important role in selecting candidatesfor breast-conserving therapy out of those patients with mammaryPaget's disease with no clinical evidence of an underlying breastcarcinoma.  相似文献   
104.
According to the World Health Organization (WHO) guidelines for patients with moderate or severe pain, morphine has been used as a "gold standard" treatment for cancer pain. Recent clinical experiences have demonstrated that when morphine is used to control pain in cancer patients, psychological dependence is not a major concern. However, undue anxiety about psychological dependence on morphine in cancer patients has caused physicians and patients to use inadequate doses of opioids. In basic research, we reported that the morphine-induced rewarding effects can be dramatically suppressed under a neuropathic pain-like state induced by sciatic nerve ligation and an inflammatory pain-like state produced by intraplantar injection of formalin or carrageenan in rodents. The use of morphine for the treatment of pain is sometimes accompanied with side effects such as emesis, constipation and drowsiness. We show that the lower doses of morphine produce emesis, whereas antinociceptive doses of morphine show no emetic responses in ferrets. These findings provide further evidence that an adequate dose of morphine is useful and safe in a clinical setting.  相似文献   
105.
Congenital cystic adenomatoid malformation (CCAM) is a congenital pulmonary anomaly, which may lead to fetal hydrops, pulmonary hypoplasia, and fetal or neonatal death. Recently, diagnosis and surgery for fetus have been improved. We experienced a case of CCAM, classified in Stocker class I, with a single cyst of about 5 cm in diameter. A 32 year-old pregnant woman had a fetus diagnosed as CCAM at 25 th gestational week. The thoraco-amniotic shunt placement using a modified double pig tail catheter was performed at 27 th gestational week under general anesthesia with 1% isoflurane in oxygen 2 l x min(-1) and nitrous oxide 4 l x min(-1), and 100 microg of fentanyl. Fetal movement was suppressed during surgery. This fetal therapy was effective and the cyst disappeared after surgery. The baby was delivered with caesarian section under spinal anesthesia with 0.5% bupivacaine 2.5 ml. On the next day, right lung lobectomy was accomplished under general anesthesia with fentanyl 0.2 mg and pancuronium 6.0 mg. Anesthesia with isoflurane, nitrous oxide, and fentanyl was useful for the fetal surgery of thoraco-amniotic shunt placement. Consequently, caesarian section and lung lobectomy were completed successfully.  相似文献   
106.
An 80-year-old man had been on maintenance hemodialysis for nondiabetic chronic renal failure from June 1996. He underwent investigation of an abnormal chest X-ray and was referred to our hospital with a diagnosis of squamous cell carcinoma in the upper lobe of the right lung. On February 20, 2003, right upper lobectomy was performed. The postoperative course was uneventful and he was discharged on postoperative day 13. Two weeks later he was readmitted with a wound infection. Although he received antibiotics, drainage, and wound lavage, his fever persisted and chest X-ray showed inflammatory changes in the right lower lung field. He was placed on mechanical ventilation for dyspnea. After this, his respiratory function became stable and he could be weaned from the ventilator within 2 weeks. The subsequent course was uneventful and he was discharged 1 month after re-admission. This patient needed ventilation due to weakness caused by wound infection. Such infection is uncommon but can be fatal for a compromised host, so we administered antibiotics for 3 days until the wound closed.  相似文献   
107.
Treatment of congenital pseudarthrosis of the tibia (CPT) remains a challenge. To clarify the current situation in treatment, a multicenter study was carried out to obtain information on the results of CPT treatment. The objective of this study was to propose appropriate treatment guidelines for CPT. Records of 73 patients with CPT who underwent surgical treatment were collected from 32 hospitals. The modality of the treatment was 26 with Ilizarov technique, 25 with free vascularized fibular graft, 7 with a combination of the two techniques, 6 with intramedullary nailing with free bone grafting, 5 plating with free bone grafting, and 4 with other treatments. Fifty-four procedures resulted in union, 7 resulted in delayed union, 7 were left un-united, 1 underwent amputation, and the results were unknown in 4. According to the results of this study, the most acceptable methods of treatment of CPT are the Ilizarov method and the vascularized fibular graft.  相似文献   
108.
We investigated the role of the caspase activation cascade in apoptosis induced by ionizing radiation or hydrogen peroxide (H(2)O(2)) in human leukemia HL60 cells. Electron paramagnetic resonance (EPR) spectra revealed that hydroxyl and hydrogen radicals were generated in the culture medium after exposure to radiation or H(2)O(2). Initial accumulation of DNA fragments at 2 h after exposure was delayed in irradiated cells compared with H(2)O(2)-treated cells, although formation of abasic sites immediately after exposure was significantly higher in irradiated cells and similar quantities of hydroxyl radicals were produced under both conditions. Activity assay of caspases revealed that caspase-3, -8 and -9 were activated 2 h after exposure to H(2)O(2), whereas in irradiated cells caspase-3 and -9 activation occurred 4 h after exposure but increased caspase-8 activation was not observed. Release of cytochrome c into cytosol was seen at 2 h after radiation and H(2)O(2) treatment. Radiation did not affect proapoptotic proteins (Bax and Bid), whereas H (2)O(2) increased accumulation of Bax in the mitochondrial membrane 2 h to 6 h after treatment, independently of the truncation of Bid by activated caspase-8. Moreover, treatment with the caspase-8 inhibitor Z-IETD-FMK increased cell survival and prevented accumulation of DNA fragments in H(2)O(2)-treated cells, but not in irradiated cells. These results suggest that, unlike the caspase cascade of H(2)O(2)-induced apoptosis, cytochrome c and caspase-9 are important for the intrinsic pathway of radiation-induced apoptosis, independent of caspase-8.  相似文献   
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