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21.
The mechanism of disinhibition produced by (±)-baclofen was studied using intracellular recording in area CA1 of rat hippocampal slices. Baclofen reversibly depressed monosynaptic IPSPs evoked by direct activation of interneurons in the presence of the excitatory amino acid receptor antagonists 6,7-dinitroquinoxaline-2,3-dione (DNQX) andd,l-2amino-5-phosphonovalerate (APV). Ba2+ prevented baclofen-induced hyperpolarization of pyramidal neurons but not depression of monosynaptic IPSPs by baclofen. Baclofen reversibly depressed monosynaptic IPSPs when applied close to the recording site, but was ineffective when applied close to the stimulating site in stratum radiatum. These results suggest that baclofen disinhibits pyramidal neurons in area CA1 of the rat hippocampus by activating receptors on the terminals of inhibitory neurons that are coupled to a Ba2+-insensitive effector mechanism.  相似文献   
22.
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
23.
The return of fertility following discontinuation of norethisterone oenanthate (NET EN) 200 mg injectable contraceptive after use for a minimum period of six months or more was studied in 69 women who discontinued the method for planning pregnancy. Former users of copper intra-uterine device (CuT 200) were enrolled as a control group. Another 161 women who had discontinued NET EN due to other reasons (e.g. amenorrhoea, excessive bleeding or personal reasons) were also studied for return of fertility after ensuring that they were not using any other method of contraception and were exposed to the risk of pregnancy. The subjects from both groups were followed for a period of one year. The cumulative conception rates at one year were 72.5 and 83.6 per 100 subjects for ex-NET EN and ex-CuT 200 users who had discontinued the method for planning pregnancy and this difference was not statistically significant (P > 0.05). The median time for conception for ex-NET EN users was 7.8 months as compared to 3.7 months in ex-CuT 200 users but the cumulative conception rates at the end of one year show that future return of fertility in NET EN users does not appear to be adversely affected.

In 51 subjects who had discontinued NET EN due to amenorrhoea, the return of fertility was predictably slower and less. The return of fertility in subjects who discontinued NET EN for other reasons (e.g. excessive bleeding and other personal reasons) was similar to ex-NET EN and ex-CuT 200 users.  相似文献   

24.
Dyssynchronous ventricular contraction in severe heart failurecontributes to low cardiac output, worsening symptoms, and poorprognosis. Recognition of the effect of dyssynchrony in heartfailure, and the possibility of manipulating the sequence ofelectrical cardiac activation to improve the efficiency of mechanicalevents, led Cazeau et al. to attempt four-chamber pacing in1994.1 This early system could stimulate both atria and bothventricles extrinsically, and could dictate the temporal relationshipbetween atrial systole and ventricular systole, and the ventriculo-ventricularrelationship. Modern cardiac resynchronization therapy (CRT),involving pacing of the right and left ventricles, with rightatrial pacing to optimize atrio-ventricular delay, has evolvedrapidly from this beginning. Left bundle branch block (LBBB) on the surface electrocardiogram(ECG) has been considered a marker of mechanical dyssynchronyas it represents a delay in conduction of depolarization tothe left ventricle, with the greatest delay usually being in  相似文献   
25.
26.
BACKGROUND: An objective of exercise-based cardiac rehabilitation is improvement in patient-reported outcomes such as health-related quality of life as well as anxiety and depressive symptoms. There are no direct comparisons of the effectiveness of inpatient and outpatient exercise-based cardiac rehabilitation programmes on patient-reported outcomes. METHODS: In this non-randomized study we collected patient-reported outcomes data with the MacNew Heart Disease health-related quality of life questionnaire and the Hospital Anxiety and Depression Scale at baseline, 1 month and again 3 months after admission to exercise-based cardiac rehabilitation in a cohort of 216 consecutive patients enrolled either in a 4-week inpatient exercise-based cardiac rehabilitation (n=62) or a 3-month outpatient exercise-based cardiac rehabilitation (n=87) and in a usual care group (n=67) to document the natural course in patient-reported outcome variables without exercise-based cardiac rehabilitation. RESULTS: Although MacNew health-related quality of life scores improved more with inpatient than outpatient exercise-based cardiac rehabilitation by month 1, the improvement was still significant in both groups at month 3 and also in the usual care group when compared to baseline. The health-related quality of life scores in the inpatient group, however, decreased between month 1 and 3 whereas they continued to improve in the outpatient group. The significant reduction in both anxiety and depressive symptoms in both exercise-based cardiac rehabilitation groups by month 1 was maintained at month 3 only with outpatient exercise-based cardiac rehabilitation. No significant changes over the 3 months were observed in the usual care group. CONCLUSION: Significant improvements of 1-month patient-reported outcomes are achieved in patients attending inpatient as well as outpatient exercise-based cardiac rehabilitation when compared with no exercise-based cardiac rehabilitation. In contrast to inpatient exercise-based cardiac rehabilitation, however, outpatient exercise-based cardiac rehabilitation leads to a further improvement of patient-reported outcomes. These results suggest that, if patients have to be admitted for inpatient exercise-based cardiac rehabilitation, this programme should be followed by an outpatient exercise-based cardiac rehabilitation to further improve and stabilize these patient-reported outcome variables.  相似文献   
27.
ObjectivesTo evaluate and summarize the evidence linking balance impairment as a risk factor for falls in community-dwelling older adults.Study Design and SettingSystematic review and meta-analysis. English language articles in MEDLINE, EMBASE, CINAHL (1988–2009), under keywords of accidental falls, aged, risk factors, and hip, radius, ulna, and humerus fractures; and bibliographies of retrieved articles. Community-dwelling older adults in a prospective study, at least 1-year duration, age more than 60 years, and samples not specific to a single disease-defined population were included. Sample size, inclusion/exclusion criteria, demographics, clinical balance measurement scale, type of fall outcome, method of fall ascertainment, length of follow-up, and odds ratio (OR) or risk ratio (RR) were extracted. Studies must have reported adjustment for confounders. Random effects meta-analysis to generate summary risk estimate was used. A priori evaluation of sources of heterogeneity was performed.ResultsTwenty-three studies met the selection criteria. A single summary measure could not be calculated because of the nonequivalence of the OR and RR, producing an overall fall risk of RR of 1.42 (1.08, 1.85) and OR of 1.98 (1.60, 2.46).ConclusionsBalance impairment imparts a moderate increase on fall risk in community-dwelling older adults. The type of fall outcome, the length of follow-up, and the balance measurement tool impact the magnitude of the association. Specific balance measurement scales were identified with associations for an increased fall risk, but further research is required to refine recommendations for their use in clinical practice.  相似文献   
28.
Object Intracranial aneurysms are rare in children and have different epidemiological, clinical, and morphological characteristics and outcome from those in adults. Materials and methods We analyzed demographic, clinical, radiologic features, treatment, and outcome in 55 patients <18 years of age, treated from Jan 1995 through December 2005. Results Intracranial aneurysms in children below 18 years constituted 4% of all intracranial aneurysms. Internal Carotid artery (ICA) bifurcation was the commonest location. About half of the aneurysms were complex. Three-fourth of the patients required surgical treatment. Two patients died, constituting 5% mortality. Two patients (5%) had poor outcome, whereas the majority (90%) had a favorable outcome. Conclusions Pediatric aneurysms have male predominance, higher incidence of clinical features of mass effect or seizures, high incidence of large, traumatic/mycotic aneurysms, associated illnesses and ICH/IVH and hydrocephalus, better Hunt and Hess grades at presentation, ICA bifurcation as the commonest site, and better outcome than their adult counterparts.  相似文献   
29.
In this study, we examined the impact of surgeon handedness on total knee arthroplasty (TKA) outcomes. From 1997 to 2001, a right-handed surgeon performed 728 primary TKAs while standing on the side of the operative extremity--377 on the right and 351 on the left. Extension and Knee Society Function and Pain scores were significantly better for right knees than for left knees 1 year after surgery. This is the first report that shows that handedness can play a role in TKA outcomes. Reasons for the difference have not been determined but may be related to dexterity or proprioception. A surgeon should be aware of this potential problem and take precautions to prevent diminished results when operating.  相似文献   
30.
Brain metastasis is the most common intracranial malignancy in adults. Improvements in modern imaging techniques are detecting previously occult brain metastases, and more effective therapies are extending the survival of patients with invasive cancer who have historically died from extracranial disease before developing brain metastasis. This combination of factors along with increased life expectancy has led to the increased diagnosis of brain metastases. Conventional treatment has been whole brain radiotherapy, which can improve symptoms, but potentially results in neurocognitive deficits. Several strategies to improve the therapeutic ratio are currently under investigation to either enhance the radiation effect, thereby preventing tumor recurrence or progression as well as reducing collateral treatment-related brain injury. In this review article, we discuss new directions in the management of brain metastases, including the role of chemical modifiers, novel systemic agents, and the management and prevention of neurocognitive deficits.  相似文献   
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