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排序方式: 共有320条查询结果,搜索用时 234 毫秒
1.
Circannual variation in lymphocyte subsets, revisited   总被引:2,自引:0,他引:2  
BACKGROUND: Circadian and circannual variations in lymphocyte subsets, especially CD8+ T-lymphocytes, have been reported. This study focuses on CD4+ T-lymphocyte seasonal variation over a 6-year 8-month period. STUDY DESIGN AND METHODS: Lymphocyte subsets were quantitated monthly for four healthy individuals from 1986 through 1992 as part of a flow cytometry quality-control program. RESULTS: In general, there were no significant seasonal changes in the total number of white cells or in total lymphocyte counts. The absolute numbers of CD4+ T-lymphocytes were lowest in summer when the CD8+ T-lymphocytes were highest. Mean CD4+ T-lymphocyte counts were 846, 967, 618, and 695 per microL for Subjects 1 through 4, respectively, in winter and 432, 670, 355, and 766 per microL, respectively, in summer. Two healthy subjects had CD4+ T-lymphocyte counts lower than 300 per microL on one or more occasions during the study period. In three of the four subjects, the percentage of B-lymphocytes in winter was almost double that in summer. In one of the four subjects, no circannual rhythm was observed in these lymphocyte subpopulations. CONCLUSION: The seasonal variation in CD4+ T- lymphocyte counts demonstrated in three healthy individuals over almost 7 years is again of interest in light of renewed consideration of using surrogate tests, such as CD4+ T-lymphocyte counts, to screen for AIDS- like diseases that may be in the blood supply.  相似文献   
2.
The family history in family practice: a questionnaire study   总被引:9,自引:7,他引:2  
Summerton  N; Garrood  PV 《Family practice》1997,14(4):285-288
OBJECTIVES: Our aims were to investigate family medical history taking in general practice, and to evaluate the value attached to the family medical history as an aid to decision making in general practice. METHOD: A postal questionnaire survey was conducted among all 291 GPs working within the Calderdale and Kirklees Health Authority area. Each questionnaire was followed by a reminder. The main outcome measures were answers to questions on routine and opportunistic family history taking and a question about transmitting knowledge about genetic risk to other members of the family. Questions were also posed about the value attached to the family medical history as an aid to decision making. RESULTS: A total of 193 GPs returned the questionnaire (response rate 66.3%). On registration, 94.3% of GPs indicated that enquiries were made about a family history of coronary heart disease. Breast and colorectal cancer were specifically asked about by 48.4% and 30.7% of GPs, respectively. One-fifth of respondents indicated that they asked a general question about family medical history. A little over one-quarter of respondents indicated that they made opportunistic enquiries about the family history or suggested that the patient should inform other members of the family about possible risks. In the scenarios highlighted in this study, the majority of respondents felt that the family medical history had value as an aid to decision making. This was particularly the case for checking a patient's cholesterol (92.1%) and for initiating referrals in younger patients with possible cancer-related symptoms (three-quarters of respondents). CONCLUSION: GPs value the family medical history as an aid to decision making. Unfortunately, apart from enquiries about coronary heart disease, routine or opportunistic family history taking is not occurring in practice. Mechanisms need to be sought to extract information from the family medical history so that it can be more effectively used by GPs.   相似文献   
3.
Fatal Familial Insomnia is a hereditary prion disease characterized by a mutation at codon 178 of the prion protein gene cosegregating with the methionine polymorphism at codon 129 of the mutated allele. It is characterized by disturbances of the wake-sleep cycle, dysautonomia and somatomotor manifestations (myoclonus, ataxia, dysarthria, spasticity). PET studies disclose severe thalamic and additionally cortical hypometabolism. Neuropathology shows marked neuronal loss and gliosis in the thalamus, especially the medio-dorsal and anterior-ventral nuclei, olivary hypertrophy and some spongiosis of the cerebral cortex. Detailed analysis of 14 cases from 5 unrelated families showed that patients ran either a short (9.1+ 1.1 months) or a prolonged (30.8 + 21.3 months) clinical course according to whether they were homozygote met/met or heterozygote met/val at codon 129. Moreover, homozygotes had more prominent oneiric episodes, insomnia and dysautonomia at onset, whereas heterozygotes showed ataxia and dysarthria at onset, earlier sphincter loss and epileptic Grand Mai seizures; they also displayed more extensive cortical involvement on PET and at postmortem examination. Our data suggest that the phenotype expression of Fatal Familial Insomnia is related, at least partly, to the polymorphism at codon 129 of the prion protein-gene.  相似文献   
4.
Nocturnal frontal lobe epilepsy (NFLE) has become clinically relevant in recent years. NFLE represents a spectrum of clinical manifestations, ranging from brief, stereotyped, sudden arousals, often recurring several times per night, sometimes with a quasi-periodic pattern, to more complex dystonic-dyskinetic seizures and to prolonged "somnambulic" behaviour. Episodes of increasing intensity have been labelled as paroxysmal arousal (PA), nocturnal paroxysmal dystonia (NPD) and episodic nocturnal wandering (ENW). NFLE affects both sexes with a higher prevalence for men, is frequently cryptogenetic and displays a strong familial trait for parasomnias and epilepsy (NFLE). Seizures appear more frequently between 14 and 20 years of age, but can affect any age and tend to increase in frequency during life. Interictal and ictal scalp electroencephalography (EEG) are often normal, the use of sphenoidal leads may be helpful. Carbamazepine taken at night is often effective at low doses, but a third of the patients are resistant to anti-epileptic drugs (AED) treatment. A familial form, characterized by an autosomal dominant transmission, has also been described. Autosomal dominant nocturnal frontal lobe epilepsy is a genetic variant of NFLE, in itself both clinically and biologically heterogeneous. NFLE should be suspected in the presence of frequent stereotyped paroxysmal nocturnal motor events arising or persisting into adulthood. Videopolysomnography is mandatory to confirm the diagnosis.  相似文献   
5.
In a retrospective cohort study undertaken in 12 European countries, 249 female narcoleptic patients with cataplexy (= 216) and without cataplexy (= 33) completed a self‐administrated questionnaire regarding pregnancy and childbirth. The cohort was divided further into patients whose symptoms of narcolepsy started before or during pregnancy (308 pregnancies) and those in whom the first symptoms of narcolepsy appeared after delivery (106 pregnancies). Patients with narcolepsy during pregnancy were older during their first pregnancy (< 0.001) and had a higher body mass index (BMI) prior to pregnancy (< 0.01). Weight gain during pregnancy was higher in narcoleptic patients with cataplexy (< 0.01). More patients with narcolepsy–cataplexy during pregnancy had impaired glucose metabolism and anaemia. Three patients experienced cataplexy during delivery. The rate of caesarean sections was higher in the narcolepsy–cataplexy group compared to the narcolepsy group (< 0.05). The mean birth weight and gestational age of neonates were within the normal range and did not differ across groups. Neonatal care was affected adversely by symptoms of narcolepsy in 60.1% of those with narcolepsy during pregnancy. This study reports more obstetric complications in patients with narcolepsy–cataplexy during pregnancy; however, these were not severe. This group also had a higher BMI and higher incidence of impaired glucose metabolism during pregnancy. Caesarian section was conducted more frequently in narcolepsy–cataplexy patients, despite cataplexy being a rare event during delivery. Furthermore, symptoms of narcolepsy may render care of the infant more difficult.  相似文献   
6.
Hypocretin/orexin signalling varies among sleep–wake behaviours, impacts upon cardiovascular autonomic control and is impaired in patients with narcolepsy with cataplexy (NC). However, evidence concerning disturbed cardiovascular autonomic control in NC patients is contrasting, and limited mainly to waking behaviour. We thus investigated whether control of cardiovascular variability is altered in NC patients during wakefulness preceding sleep, light (1–2) and deep (3–4) stages of non‐rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Polysomnographic recordings and finger blood pressure measurements were performed on nine drug‐free male NC patients and nine matched healthy control subjects during spontaneous sleep–wake behaviour in a standardized laboratory environment. Indices of autonomic function were computed based on spontaneous fluctuations of systolic blood pressure (SBP) and heart period (HP). During wakefulness before sleep, NC patients showed significant decreases in indices of vagal HP modulation, cardiac baroreflex sensitivity and amplitude of central autonomic (feed‐forward) cardiac control compared with control subjects. During NREM sleep, the negative correlation between HP and subsequent SBP values was greater in NC patients than in control subjects, suggesting a greater contribution of central autonomic commands to cardiac control. Collectively, these results provide preliminary evidence that autonomic control of cardiac variability by baroreflex and central autonomic (feed‐forward) mechanisms is altered in NC patients during spontaneous sleep–wake behaviour, and particularly during wakefulness before sleep.  相似文献   
7.
8.

Purpose

In Parkinson’s disease (PD) patients, REM sleep behavior disorder (RBD) might precede PD or develop with or after the onset of PD. No previous study has explored differences between these two groups. The aim of this study was therefore to compare clinical features and REM sleep chin electromyographic patterns between patients in whom RBD heralded PD and those in whom RBD occurrence coincided with or followed the clinical manifestations of PD.

Method

Twenty-seven consecutive PD patients (mean age 67.9 years) were enrolled. Detailed clinical, laboratory, and polysomnographic studies were obtained in all participants.

Results

Sixteen of the 27 patients were affected by RBD. These had a significantly higher stage of PD and took significantly higher doses of dopaminergic therapy; their disease duration tended to be longer, and their cognitive status tended to be lower. PD patients in whom RBD preceded PD (n?=?6) did not differ from PD patients without RBD in disease parameters, while PD patients in whom RBD developed with or after PD (n?=?10) showed a significantly higher disease stage, took significantly higher dopaminergic therapy, and had a longer disease duration.

Conclusion

Our findings are compatible with the hypothesis that patients in whom RBD precedes, or does not precede, PD might constitute two possibly distinct clinical and physiopathological groups, based on different progressive neuropathological sequences of events.  相似文献   
9.
Sleep and Breathing - Narcolepsy is a disabling, rare, and chronic sleep disorder, currently classified as distinct central nervous system hypersomnia in narcolepsy type 1 (NT1) and narcolepsy type...  相似文献   
10.
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