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71.
The endogenous opioid system is implicated in excessive ethanol-drinking behavior. However, the role of individual opioid receptor subtypes in the mechanism underlying excessive ethanol-drinking behavior is not yet well understood. Therefore, we investigated the ability of a selective micro1-opioid antagonist, naloxonazine, to modulate ethanol-drinking behavior and ethanol discrimination in a rat model with the use of ethanol self-administration and drug discrimination paradigms. The effects of naloxonazine (0.001-10 mg/kg) on ethanol intake were examined in Sprague-Dawley rats under conditions of limited access to 10% (wt./vol.) ethanol and ad libitum access to food and water. Pretreatment with high doses of naloxonazine (1-10 mg/kg) significantly reduced ethanol consumption. When the effects of naloxonazine on food intake in free-feeding male rats were examined, naloxonazine (1.8-10 mg/kg) significantly suppressed 24-h food intake. Another group of rats was trained to discriminate ethanol (1.25 g/kg, i.p.) from saline on a fixed-ratio schedule (FR 10), and ethanol dose-response tests were conducted once rats had acquired ethanol-saline discrimination. Injections were given 15 min before ethanol dose-response tests were conducted, and after characterization of the ethanol dose-response curve, the effects of naloxonazine on ethanol discrimination were assessed by administering naloxonazine (0.001-10 mg/kg, i.p.) 15 min before ethanol administration. Treatment with naloxonazine (0.001-1.8 mg/kg, i.p.) before the ED(100) dose of ethanol partially antagonized the discriminative stimulus of ethanol without having any effect on the response rate. The results support the suggestion of involvement of micro1-opioid receptors in the discriminative effects of ethanol and ethanol-drinking behavior.  相似文献   
72.
The Swedish Knee Arthroplasty Register has data on 4, 381 primary operations performed 1985-1995 for rheumatoid arthritis. Of these, 192 were performed with unicompartmental prostheses and 4143 with tricompartmental. 77% were women and the mean age was 66 years. There were 126 first, 20 second, and 1 third revision in tricompartmental arthroplasties, mainly for loosening, infection and patellar problems. There were 38 first, 3 second, and 1 third revision in unicompartmental arthroplasties, mainly for progression of RA and loosening .

Cumulative revision rates (Kaplan-Meier) were calculated. Tricompartmental knees had a 10-year cumulative revision rate of 5% and uni-knees 25%. Patients treated before 1990, men and patients younger than 55 had higher revision rates than patients treated after 1990, women and older patients, respectively. Cemented tibial components resulted in lower revision rates than uncemented ones. There was no significant difference in revision rates between patellar replaced and unreplaced knees or between the 9 commonest implant types.  相似文献   
73.
A 21-year-old man was injured by a tailboard of a truck. He suffered a severe head injury with bilateral depressed skull fractures necessitating surgical decompression. On admission to the hospital the patient showed bending to pain stimuli (Glasgow Coma Score 5). Anisocoria was noticed from the beginning. Initial intracranial pressure (ICP), measured 3 hours after injury, was 30 mm Hg, and the cerebral perfusion pressure (CPP) was 70 mm Hg. During surgical elevation of the skull fracture on the right side an unexplainable rise of ICP to values of 100 mm Hg occurred, which corresponded to the mean arterial blood pressure (MAP). At the same time both pupils were dilated and fixed indicating a lack of cerebral perfusion. Due to immediate trephination of the opposite side, the ICP was lowered to values below 20 mm Hg, and sufficient cerebral perfusion (above 50 mm Hg) was regained. The patient showed a good recovery and was transferred to a rehabilitation center 5 weeks after injury.This case report emphasizes the importance of early and continuous intracranial pressure monitoring for adequate therapy in neurosurgical emergencies.  相似文献   
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Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed.  相似文献   
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Abstract: Lobular carcinoma in situ (LCIS) has gone from a rare form of mammary cancer to a marker of increased risk. Treatment options have undergone a corresponding change from ipsilateral mastectomy with axillary node dissection to observation once it became clear that the majority of patients did not progress to invasive cancer. However, recent events suggest a re-evaluation of LCIS management options. It is clear that even meticulous observation may fail to detect invasive cancer before systemic spread has taken place. This fact plus the identification of breast cancer genes have brought a renewed interest in prophylactic mastectomy. At the same time pathologists feel that it is possible to identify microscopic features of LCIS pointing to an increased likelihood of developing invasive cancer. As a result physicians are being asked to better quantitate risks for individual patients. Most patients with LCIS do not need bilateral mastectomies, but we are coming closer to identifying the minority that would be better served by prophylactic surgery.  相似文献   
79.
Fungal infections still represent a serious complication after organ transplantation. Early diagnosis and aggressive treatment are crucial. Because of the many diagnostic problems involved, we present a case of mucormycosis--primarily affecting the paranasal sinuses with later intracranial extension--in a highly immunized recipient of a third renal transplant. Although fungal infection was suspected from various imaging techniques, only the detection of typical fungal hyphae in the infected tissue was diagnostic. Neither the blood tests and cerebrospinal fluid examinations performed nor cultures from maxillary sinus fluid were of any diagnostic help. Surgical debridement from a transnasal as well as an intracranial approach and systemic amphotericin B together with the discontinuation of immunosuppression after removal of the rejected graft were able to save the patient. This case stresses the importance of early diagnosis that can only be made from tissue biopsies and allows appropriate timely treatment.  相似文献   
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