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681.
Mild-to-moderate thrombocytopenia has been reported as an occasional finding in patients with iron deficiency. The present case describes a multiparous woman who presented with increased menorrhagia, severe anemia (3.0 g/dl) and thrombocytopenia (9,000 platelets/mm3). Her bone marrow examination showed iron deficiency, megakaryocytopenia, and erythroid hypoplasia but no other evidence of a primary marrow disorder. Her symptoms, the thrombocytopenia and the megakaryocytopenia, resolved with iron replacement. This case demonstrates the profound degree to which thrombopoiesis can be affected in iron deficiency.  相似文献   
682.
Infection of resistant or susceptible mice with Trichuris muris provokes mesenteric lymph node responses which are polarized towards Th2 or Th1, respectively. These responses are well documented in the literature. In contrast, little is known about the local responses occurring within the infected intestine. Through microarray analyses, we demonstrate that the gene expression profile of infected gut tissue differs according to whether the parasite is expelled or not. Genes differentially regulated postinfection in resistant BALB/c mice include several antimicrobial genes, in particular, intelectin (Itln). In contrast, analyses in AKR mice which ultimately progress to chronic infection provide evidence for a Th1-dominated mucosa with up-regulated expression of genes regulated by gamma interferon. Increases in the expression of genes associated with tryptophan metabolism were also apparent with the coinduction of tryptophanyl tRNA synthetase (Wars) and indoleamine-2,3-dioxygenase (Indo). With the emerging literature on the role of these gene products in the suppression of T-cell responses in vitro and in vivo, their up-regulated expression here may suggest a role for tryptophan metabolism in the parasite survival strategy.  相似文献   
683.
The present study compared imitation performance in patients with ideomotor apraxia (IMA), eight right hemispheric-damaged patients, and eight control participants without neurological damage in three experiments. Experiment 1 confirmed in the Goldenberg test that IMA patients were particularly impaired in hand gestures and combined finger and hand gestures, but not in the imitation of finger gestures, compared to the other two groups. Experiment 2, however, demonstrated that finger selection is not per se preserved in imitative behaviour in patients with IMA. Experiment 3 confirmed this finding in an experiment under visual control. Together, the results add evidence to the idea that imitation should be viewed from a goal-directed rather than a body-mapping perspective, and that highest priority is given to more distal aspects of imitation as reaching for the correct object, rather than the means used to achieve the goal of a modelled action.  相似文献   
684.
硝苯啶的光解分析法及其在透皮吸收研究中的应用   总被引:1,自引:0,他引:1  
A new method of analysis for low concentrations nifedipine was developed according to the principle of a photodegradation analytical method that has been reported by the authors previously, and was used to study percutaneous absorption. The absorbance of sample solution was measured before and after light irradiation at 237 nm for 2 h. In this method, calibration graph was linear in the range of 1~20μg/ml for △A237. The average recovery for nifedipine was 98.80%. No interference from propylene glycol, azone, m-nifedipine, nitrendipine, verapamil and propranolol was observed. It is shown that azone can promote markedly percutaneous absorption of nifedipine.  相似文献   
685.
It is widely accepted that patients with frontal lesions have problems inhibiting automatic response tendencies. Whereas inhibition deficits of overlearned responses have been extensively investigated using interference tasks like the Stroop task (J. R. Stroop, 1935), it is controversial whether patients with frontal brain lesions also have problems inhibiting imitative responses. Using an interference paradigm, the present study investigated imitative response tendencies in patients with frontal lesions. In addition, it tested whether patients deficient in the inhibition of imitative responses correspondingly have problems inhibiting overlearned responses. It was found that the group with frontal lesions displayed significantly stronger imitative response tendencies than the group with nonfrontal lesions. Furthermore, it was shown that the inhibition of imitative responses is functionally unrelated to Stroop interference.  相似文献   
686.
687.
BACKGROUND: Racial differences in stroke mortality are widely recognized, but it is unclear whether or not these differences are due mainly to blacks having a greater stroke incidence or higher case fatality rates compared to those of whites. OBJECTIVES: The aim of this study was to describe the race-specific US trends in hospital discharge rates and in-hospital mortality among stroke patients for the period 1980-1999. It was hypothesized that the hospital discharge rates and in-hospital mortality among stroke patients would be greater for blacks than for whites. METHODS: Data from the National Hospital Discharge Survey for the period 1980-1999 were used to identify stroke subjects according to the codes of the International Classification of Diseases, ninth revision (codes 430-434 and 436). Direct standardization and Poisson regression were used to compare hospitalized stroke morbidity and mortality rates between blacks and whites. The main outcome measures were the number of stroke discharges and in-hospital deaths for black and white stroke patients. RESULTS: Between the years 1980 and 1999, the hospital discharge rates for stroke increased for blacks (n = 8,700) and decreased for whites (n = 46,154); the in-hospital mortality rates decreased for both black and white stroke patients. Generally, the risk of a stroke hospitalization was greater for blacks than for whites by more than 70%, whereas both groups were similar in terms of in-hospital mortality rates among stroke patients. CONCLUSIONS: Differences between blacks and whites in terms of stroke mortality are more likely due to differences in stroke incidence rather than case fatality. These data imply that greater attention should be given to primary/secondary prevention and that additional research is needed to understand the reasons for these patterns.  相似文献   
688.
BACKGROUND/AIMS: Peripheral arterial disease (PAD) has been suggested as a contributing factor to the development of intradialytic muscle cramps in patients on maintenance hemodialysis. METHODS: To test this hypothesis, 122 patients from two dialysis centers were studied. The presence of PAD was determined by measurement of the ankle-brachial index (ABI) in the lower extremities of patients pre- and postdialysis. The experience of intradialytic cramps was assessed using patient history and review of medical records. RESULTS: PAD defined as a predialysis ABI < or =0.90 had an overall prevalence of 16.4% among patients studied. The prevalence of PAD was age-dependent, reaching 37.5% in patients 80-89 years old. Intradialytic muscle cramps were common, with 52.1% of patients reporting cramps within the previous two months, but there was no relationship between cramps during dialysis and PAD (p > 0.05). CONCLUSIONS: PAD was common in hemodialysis patients, but there was no association between the presence of PAD and the prevalence of intradialytic muscle cramps.  相似文献   
689.
690.
The effect of gadolinium diethylenetriaminepentaacetic acid (DTPA) on the sensitivity of cranial magnetic resonance (MR) imaging was measured in a prospective blinded study. Twenty-two consecutive patients with benign extraaxial tumors underwent MR imaging on a 1.5-T system without and with intravenous administration of Gd-DTPA. Readers independently interpreted the unenhanced and enhanced images without clinical information. The interpretations were compared with the anatomically verified diagnoses. Gd-DTPA improved the sensitivity of MR imaging for benign extraaxial tumors, especially in cases of residual or recurrent acoustic neuromas, multiple tumors (e.g., neurofibromatosis), or inconclusive unenhanced MR images. Enhancement with Gd-DTPA impaired the identification of a skull base tumor.  相似文献   
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