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61.
BACKGROUND: Aspirin is an effective and generally accepted treatment drug during the acute stage of ischemic brain infarction. The association between the pretreatment aspirin dosage and fatal outcome among these treated patient groups has not been analyzed previously. OBJECTIVE: The aim of the study was to evaluate 14- and 30-day poststroke survival in patients treated with 325 mg immediately on admission to the hospital for prestroke antiaggregation/anticoagulation treatment. METHODS: This prospective study was conducted in a government tertiary care facility. The medical records of all 1245 patients admitted to the hospital for stroke from 1997 to 2002 were reviewed. The association between demographic parameters, stroke risk factors, stroke subtype, prestroke antiaggregation/anticoagulation treatment, and risk of fatal poststroke outcome, 14 days and 30 days after the event, was analyzed using Cox survival analyses. RESULTS: During the 14-day poststroke period, 320 patients (25%) died. By day 30 poststroke, 386 patients (31%) had died. Older age, female gender, chronic heart disease, and cardiac arrhythmias were associated with increased risk of increased fatal outcome. Mortality was higher in patients with stroke caused by cardioembolism (P < 0.0001) and was significantly lower in patients with small-vessel occlusion (P < 0.0001). Prestroke medium-dose aspirin treatment was associated with a relative reduction in 30-day poststroke period mortality (P < 0.0001). Conversely, prestroke low-dose aspirin treatment was associated with increased mortality (P < 0.0001). CONCLUSION: Prestroke medium-dose aspirin treatment was associated with reduced 30-day poststroke mortality, whereas low-dose prestroke aspirin therapy was associated with increased 30-day poststroke mortality.  相似文献   
62.
Dorsal root ganglia (DRG) are key elements in sensory signaling under physiological and pathological conditions. Little is known about electrical coupling among cells in these ganglia. In this study, we injected the fluorescent dye Lucifer yellow (LY) into single cells to examine dye coupling in DRG. We found no dye coupling between neurons or between neurons and their attendant satellite glial cells (SGCs). In mouse DRG, we observed that in 26.2% of the cases SGCs that surround a given neuron were dye coupled. In only 3.2% of the cases SGCs that make envelopes around different neurons were coupled. The data from mouse ganglia were very similar to those from rat and guinea pig DRG. The results obtained by injection of the tracer biocytin were very similar to those observed with LY. The coupling incidence within the envelopes increased 3.1-fold by high extracellular pH (8.0), but coupling between envelopes was not affected. Acidic pH (6.8) reduced the coupling. High extracellular K+ (9.4 mM) increased the coupling 2.4-fold and 4.7-fold within and between envelopes, respectively. Low extracellular Ca2+ (0.5, 1.0 mM) partly reversed the effect of high K+ on coupling. The results showed that SGCs in mammalian sensory ganglia are connected by gap junctions. This coupling is very sensitive to changes in pH, and can therefore be modulated under various physiological and pathological conditions. The dependence of the coupling on extracellular K+ and Ca2+ suggests that the permeability of gap junctions can be altered by physiological and pharmacological stimuli.  相似文献   
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64.
OBJECTIVE: Parotid gland enlargement due to diffuse pathologic processes represents a diagnostic challenge for the surgeon. In such cases, fine-needle aspiration is inconclusive and superficial parotidectomy is usually performed. MATERIAL AND METHODS: The authors treated eight patients who underwent open incisional biopsy of the parotid gland with continuous monitoring of the facial nerve. RESULTS: In all cases, fine-needle aspiration cytology did not provide a definitive diagnosis while open incisional biopsy provided an accurate diagnosis of a lymphoproliferative disorder, with no operative complications. CONCLUSION: In certain infiltrative parotid diseases such as lymphoepithelial or lymphoproliferative diseases, when fine-needle aspiration biopsy is insufficient as tissue architecture is an important component of the pathological diagnosis, an open incisional biopsy can be considered. This procedure can provide an accurate histological diagnosis while avoiding superficial parotidectomy.  相似文献   
65.
OBJECTIVE: The purpose of this study was to determine whether the rate of preeclampsia in pregnant diabetic women is increased in those women with early-pregnancy proteinuria of 190 to 499 mg/24 hours compared with women with proteinuria of <190 mg/24 hours. STUDY DESIGN: Secondary analysis was performed with relevant data from 194 pregnant women with type 1 and type 2 diabetes mellitus whose condition required insulin and who were enrolled previously in a multicenter trial of low-dose aspirin for the prevention of preeclampsia. The women were assigned to 1 of 3 groups, based on the level of proteinuria at enrollment (13-26 weeks of gestation). Group 1 comprised women with <190 mg protein/24 hours (n=94); group 2 comprised women with 190 to 499 mg protein/24 hours (n=35); and group 3 comprised women with >/=500 mg protein/24 hours (n=65). The rate of preeclampsia, according to strict predefined criteria, was then determined. RESULTS: The rate of preeclampsia was not increased statistically significantly in patients with early-pregnancy proteinuria of 190 to 499 mg/24 hours (7/35 women; 20%) when compared with women with proteinuria of <190 mg/24 hours (16/94 women; 17%). CONCLUSION: We did not find an increased rate of preeclampsia in women with pregestational diabetes mellitus with early-pregnancy proteinuria of 190 to 499 mg/24 hours when compared with women with pregestational diabetes mellitus with proteinuria of <190 mg/24 hours.  相似文献   
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67.
Cherkas PS  Huang TY  Pannicke T  Tal M  Reichenbach A  Hanani M 《Pain》2004,110(1-2):290-298
Damage to peripheral nerves induces ectopic firing in sensory neurons, which can contribute to neuropathic pain. As most of the information on this topic is on dorsal root ganglia we decided to examine the influence of infra-orbital nerve section on cells of murine trigeminal ganglia. We characterized the electrophysiological properties of neurons with intracellular electrodes. Changes in the coupling of satellite glial cells (SGCs) were monitored by intracelluar injection of the fluorescent dye Lucifer yellow. Electrophysiology of SGCs was studied with the patch-clamp technique. Six to eight days after axotomy, the percentage of neurons that fire spontaneously increased from 1.6 to 12.8%, the membrane depolarized from -51.1 to -45.5 mV, the percentage of cells with spontaneous potential oscillations increased from 19 to 37%, the membrane input resistance decreased from 44.4 to 39.5 MOmega, and the threshold for firing an action potential decreased from 0.61 to 0.42 nA. These changes are consistent with increased neuronal excitability. SGCs were mutually coupled around a given neuron in 21% of the cases, and to SGCs around neighboring neurons in only 4.8% of the cases. After axotomy these values increased to 37.1 and 25.8%, respectively. After axotomy the membrane resistance of SGCs decreased from 101 MOmega in controls to 40 MOmega, possibly due to increased coupling among these cells. We conclude that axotomy affects both neurons and SGCs in the trigeminal ganglion. The increased neuronal excitability and ectopic firing may play a major role in neuropathic pain.  相似文献   
68.
The relationships between acute life events and type of depression were evaluated among inpatient adolescents with schizophrenia. Forty-two adolescent inpatients were assessed, 25 with schizophrenia and 17 with personality disorder. Acute life events and other psychosocial situations were identified with the ICD-10 Axis V semistructured interviews. The Depression Equivalent Questionnaire for Adolescents (DEQ-A) and the Positive and Negative Symptom Scale (PANSS) were used to measure quality and severity of depression. In the patients with schizophrenia, psychosocial situations were related to the anaclitic type of depression, whereas in the subjects with personality disorder, they were highly correlated with introjective depression. In the schizophrenic group, the psychosocial situations related to depression were of a more intrapersonal nature and, in the personality-disordered group, they were more interpersonal. Environmental factors play an important role in the course of schizophrenia in adolescents and should remain a focus of study. Object relations theory may be of heuristic value in the investigation of these factors.  相似文献   
69.
Sadeh M  Gilad R  Dabby R  Blumen SC 《Neurology》2004,62(8):1424-1425
Muscle strength was assessed in 11 patients with radial or posterior interosseus palsy. Apparent weakness was found in the dorsal and palmar interossei and the abductor digiti minimi. These muscles insert on the extensor expansions, and their activation is associated with concomitant contraction of finger flexors and extensors. This apparent weakness may be due to their unopposed traction on the extensor expansion by the paralyzed extensor digitorum.  相似文献   
70.
OBJECTIVE: To examine the association between prelabor uterine contraction frequency (UCF) and the success of tocolytic therapy for preterm labor (PTL). STUDY DESIGN: Eleven centers conducted a prospective, observational study of UCF recorded between 22(0/7) and 36(6/7) weeks' gestational age or until delivery > or = 2 times/d on > or = 2 d/wk in women with singleton pregnancies with and without risk factors for preterm birth. Uterine contraction data obtained from patients diagnosed with PTL allowed comparison of mean UCF both before and after an acute episode of PTL treated with either intravenous, subcutaneous or oral tocolysis. The signed rank test was used to analyze differences in UCF before and after tocolytic therapy and between women who were or were not successfully treated with a labor-inhibiting agent. RESULTS: Of 454 enrolled women, 128 were diagnosed with PTL, and 74 were successfully treated with a labor-inhibiting agent. The mean UCF preceding PTL was not different between those women successfully treated and those who delivered as a consequence of the PTL episode. There was no difference (P = .653) in mean UCF between the week before PTL (UCF 0.60 +/- 0.8, median 0.30) and the first week of monitoring after successful tocolysis (UCF 0.82 +/- 1.4, median 0.27). CONCLUSION: The mean UCF immediately preceding PTL does not predict tocolytic success or failure.  相似文献   
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