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Acute administration of reserpine induces Fos expression in striatopallidal neurons, an effect blocked by pretreatment with the D2 dopamine agonist quinpirole. Pretreatment with the NMDA antagonists (+)MK-801 or CPP attenuated reserpine-mediated striatal Fos induction whereas pretreatment with ketamine or the inactive isomer (-)MK-801 did not. These results support a role of NMDA glutamate receptors in regulating the activity of the striatopallidal pathway.  相似文献   
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BACKGROUND: There has been a reluctance to use regional blocks for women with multiple sclerosis as effects on the course of the disease are unclear. We assessed the views of UK consultant obstetric anaesthetists regarding management of women with multiple sclerosis. METHODS: Following Obstetric Anaesthetists' Association approval a questionnaire was sent to UK consultant members. Opinions were sought on antenatal assessment, labour analgesia, anaesthesia for elective and emergency caesarean section, and modification in technique for those with multiple sclerosis. Enquiries were made of postnatal problems ascribed to regional blocks. RESULTS: Of the 592 replies analysed, 91% of respondents had seen fewer than 10 cases of multiple sclerosis in the past 10 years. Antenatal assessment was recommended by many with postnatal relapse most commonly discussed (64%). Many highlighted the need for informed consent and minimising local anaesthetic dose. For labour analgesia 79% would perform a regional block; a further 20% would do so in certain circumstances. For elective caesarean section, epidural rather than spinal anaesthesia was preferred by 4%; 2% would not use a regional block, preferring general anaesthesia. For emergency caesarean section with time only for single-shot spinal, 3% would give a general anaesthetic. Deterioration of symptoms after delivery were reported by 20% with 3% attributing symptoms such as prolonged block, leg weakness, bladder dysfunction and postnatal relapse to regional blocks. CONCLUSION: Most UK anaesthetists would perform regional blocks for labour and caesarean section in multiple sclerosis, although the experience of each anaesthetist is limited. Many emphasised the need for thorough pre-assessment and informed consent.  相似文献   
996.

Background

The hypercoagulable state results from a complex interplay of blood coagulation factors, coagulation-inhibitory factors, platelets and the vascular endothelium. Imbalance of the complex interplay between these factors results in thrombosis often complicated by embolism. The causes of thrombosis are varied and maybe congenital or acquired. The current interest is centered on the congenital deficiency of coagulation inhibitors as there is an increasing awareness of their involvement in thrombosis, especially in the young.

Methods

A total of 42 patients with thrombosis were studied. The most common clinical presentation was deep vein thrombosis. All the cases were evaluated for coagulation inhibitors Antithrombin, resistance to activated protein C, Protein C and Protein S using standard assay kits.

Results

Resistance to activated protein C (n=10) was seen to be the commonest cause of thrombophilia. This was followed by deficiency of Antithrombin (n-4), Protein C (n=3) and Protein S (n=2). Majority of our cases were in the third decade of life.

Conclusion

The identification of the underlying aetiology is important for instituting specific therapy and patient management.Key Words: Thrombophilia, Coagulation inhibitors  相似文献   
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Biology of colorectal liver metastases: A review   总被引:1,自引:0,他引:1  
Metastatic growth is a selective, non-random process, which in the case of colorectal cancer, frequently occurs in the liver and is the major cause of cancer related death in these patients. This review summarises attempts to find biological and molecular markers of metastasis and their role in establishment of secondary tumours. Recent evidence suggests that liver metastases are phenotypically different to the primary from which they were derived and thus represent a separate disease entity.  相似文献   
999.
PURPOSE: The Drusen Laser Study evaluated macular laser to prevent choroidal neovascularization (CNV) and vision loss in high-risk age-related maculopathy (ARM). DESIGN: Prospective, interventional, randomized, controlled clinical trial in five hospital centers. METHODS: Patients in the unilateral group had neovascular ARM and drusen in the study eye. Study eyes were randomized to laser-treated or no-laser groups. For patients in the bilateral drusen group, eyes were randomized to right eye, laser or no laser; and left eye, alternative. Laser treatment comprised 12 argon spots. Outcome was best-corrected visual acuity and CNV signs, which were monitored for 3 years. RESULTS: In the unilateral group, vision loss occurred in 21 (28.8%) of 73 patients in laser vs 13 (19.7%) of 66 no-laser patients (P=.214). Incidence of CNV was 27 (29.7%) of 91 in laser vs 15 (17.65%) of 85 no-laser patients (P=.061). CNV onset was approximately 6 months earlier in laser-treated compared with no-laser patients (P=.05). In the bilateral group, vision loss occurred in six (8.3%) of 72 laser-treated vs 10 (13.9%) of 72 fellow eyes (P=.3877). CNV incidence was 12 (11.6%) of 103 in laser-treated vs seven (6.8%) of 103 fellow eyes (P=.225). There was no difference in onset of CNV. CONCLUSIONS: Results do not support prophylactic laser of the fellow eye of patients with neovascular ARM. Its role in patients with bilateral drusen remains unclear.  相似文献   
1000.
OBJECTIVES: We examined correlates of deliberate sexual abstinence among gay/bisexual men, heterosexual men, and women in a national probability sample of adults with HIV. METHODS: Participants in the HIV Cost and Services Utilization Study (HCSUS; n=1339) answered questions about oral, anal, or vaginal sexual intercourse in the past 6 months; those who reported none of these behaviors (n=415) were asked about their reasons for abstinence. Of these, 201 participants (11% of gay/bisexual men, 18% of women, 18% of heterosexual men) indicated that their abstinence was deliberate. Multivariate models were used to predict deliberate abstinence. RESULTS: In multivariate analyses, not having a primary relationship partner/spouse was a significant correlate of deliberate abstinence for all 3 groups. Higher perceived responsibility for limiting disease transmission and nondrinking status were related to deliberate abstinence only among gay/bisexual men. Worse health was associated with deliberate abstinence only among heterosexual men. CONCLUSIONS: Perhaps because HIV is more common in gay communities, abstinence choices may be more closely linked to a higher sense of responsibility for reducing transmission among gay/bisexual men, and their illness may be less of an impediment to sexual activity.  相似文献   
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