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11.
To determine whether the vomeronasal system of the Brazilian short-tailed opossum (Monodelphis domestica) is important to the response to conspecific chemical signals, the authors tested female opossums with conspecific odors, before and after ablation of their accessory olfactory bulbs (AOBs). Anesthesia and sham treatments did not modify females' discrimination of conspecific odors when tested against water, between male and female odors, or between different odors from the same male donors. Odor investigation was partially diminished following partial ablation of the AOB, and complete ablation of the AOBs further impaired the ability of females to discriminate between certain odors. These findings provide the first evidence for the importance of the vomeronasal system in the detection of chemosignals of known origin in opossums.  相似文献   
12.
Regression of v-src DNA-induced sarcomas is under host genetic control.   总被引:1,自引:0,他引:1  
Previous results have established that subcutaneous inoculation of chickens (line SC) with a v-src(+) subviral DNA fragment induces the formation of progressor sarcomas at the wing web site of inoculation. Because the sarcoma cells are incompetent for production of exogenous progeny virus, this system is a useful model of tumor expansion by sarcoma cell division, in the absence of infection-mediated recruitment of new tumor cells. The present study was undertaken to define conditions that modulate the pattern of growth (regression vs progression) of v-src DNA-induced sarcomas. These conditions were found to include the line of chicken or the presence on the subviral v-src(+) DNA fragment of a viral replication-specific sequence that includes env.  相似文献   
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This article reviews the results obtained on 262 VK partial and total temporomandibular joint (TMJ) procedures followed up to 10 years. VK I total joint (placed 1982 to 1986) cumulative success rate was 44% at 6 years and 20% at 10 years, while VK II (placed 1986 to 1990) cumulative success rate was 80% at 6 years. Material wear of the Teflon FEP surface of the VK I fossa was the most common reason for failure. There were no VK II material failures. A significant improvement in clinical success parameters for both prostheses was found if no previous surgeries were done before VK I or VK II total joint placement. Rib grafts were not helpful after removal of total joint prostheses if patients had a history of multiple procedures. Total TMJ prostheses must be reserved for patients with alternative surgical failures or when these procedures are no longer indicated. Close monitoring by clinical examination and imaging is necessary.  相似文献   
16.
Objective: The objectives of this study were to assess the efficacy of medical management for vulvar vestibulitis and to examine several historical variables and determine their predictive values as to which treatments will be most successful.Methods: Seventy-four patients diagnosed with vulvar vestibulitis were evaluated. Each patient was treated using a sequence of consecutive medical therapies for vulvar vestibulitis. These therapies were topical aqueous 4% lidocaine with intercourse, topical corticosteroid therapy, oral amitriptyline, topical low-dose 5-fluorouracil (5-FU) cream, intralesional alpha-interferon, and a low-oxalate diet in combination with oral calcium citrate. The patients were followed over 3-30 months and their responses to therapy were assessed. In addition, a statistical analysis was performed to determine the positive predictive values of certain historical variables and specific treatment successes. Results: Forty-nine patients reported positive responses to one of the initiated therapies. More specifically, 18.1% of the patients who used lidocaine, 33.8% who used topical corticosteroids, 57.1% who used amitriptyline, 16.7% who used 5-FU, none who received interferon, and 50% who tried a low-oxalate diet had positive responses to therapy. No historical variables were predictive of which therapies would have the most successful outcome.Conclusions: Medical management is effective in alleviating the symptoms of vulvar vestibulitis. Various aspects of a patient's history are not helpful in selecting the therapy that will be most effective.  相似文献   
17.
Background: Based on a clinical observation that the conversion rate of laparoscopic cholecystectomy (LC) to open cholecystectomy (OC) is higher in males, we decided to review our records and to verify whether a significant difference in conversion rates exists between sexes. Methods: A retrospective study on conversion rates of elective laparoscopic cholecystectomy (LC) into open cholecystectomy (LC) in relation to gender was carried out in 329 patients: 267 females and 62 males. Results: Our data revealed that the probability of conversion is fivefold greater in males than females, 21% vs 4.5%, respectively (p=0.0001). We attribute this striking difference to significantly more adhesions (p=0.0002) and anatomical difficulties (p=0.003) in males during LC, leading to conversion. Conclusions: We conclude that conversion of LC to OC is more prevalent among males and is probably attributable to a greater incidence of anatomical difficulties.  相似文献   
18.
Social class and health are inextricably linked, so it will take more than improvements in direct health care to reduce inequalities, says the report of Sir Douglas Black's working party. Its recommendations, therefore, go beyond health and social service provision and have given the report broader political implications than had been expected. Here, Stephen Halpern looks in detail to the Black report's findings and proposals and the reactions to it.  相似文献   
19.
Political dogma or an attempt to bring hospital services closer to the people? The Government's policy on hospital size as expressed in a new consultation paper is sure to be controversial; Stephen Halpern looks at the proposals and their implications for hospital staff, patients and the NHS.  相似文献   
20.
When a hospital is continually evolving one year brings no dramatic changes but evolution goes on. Stephen Halpern visited a long established hospital in Wales.  相似文献   
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