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1.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
2.
DC-SIGN是DC表面识别多种病原微生物的受体.一方面,DC借助DC-SIGN对固有免疫及适应性免疫发挥免疫调节作用;另一方面,DC-SIGN又成为某些病原微生物如肝炎病毒借以逃逸机体免疫防御功能的靶分子.我们就DC-SIGN的结构及功能、与病毒的相互作用等方面进行阐述. 相似文献
3.
Maria I. Georgi Julia Rosendahl Franziska Ernst Dorothee Günzel Jörg R. Aschenbach Holger Martens Friederike Stumpff 《Pflügers Archiv : European journal of physiology》2014,466(9):1689-1712
It has long been established that the absorption of short-chain fatty acids (SCFA) across epithelia stimulates sodium proton exchange. The apically released protons are not available as countercations for the basolateral efflux of SCFA anions and a suitable transport model is lacking. Patch clamp and microelectrode techniques were used to characterize an anion conductance expressed by cultured cells of the sheep and bovine rumen and the sheep omasum and to localize the conductance in the intact tissue. Cells were filled with a Na-gluconate solution and superfused with sodium salts of acetate, propionate, butyrate, or lactate. Reversal potential rose and whole cell current at +100 mV decreased with the size of the anion. Anion-induced currents could be blocked by diisothiocyanato-stilbene-2,2′-disulfonic acid (DIDS), NPPB (200?μmol l?1), or pCMB (1 mmol l?1). In patches of bovine ruminal cells, single channels were observed with a conductance for chloride (327?±?11 pS), acetate (115?±?8 pS), propionate (102?±?10 pS), butyrate (81?±?2 pS), and gluconate (44?±?3 pS). Channels expressed by sheep rumen and omasum were similar. Microelectrode experiments suggest basolateral localization. In conclusion, forestomach epithelia express basolateral maxi-anion channels with a permeability sequence of chloride?>?acetate?>?propionate?>?butyrate. SCFA absorption may resemble functionally coupled transport of NaCl, with the Na+/K+-ATPase driving the basolateral efflux of the anion through a channel. Since protons are apically extruded, the model accurately predicts that influx of buffers with saliva is essential for the pH homeostasis of the ruminant forestomach. 相似文献
4.
BRCA1 and BRCA2 are major breast cancer susceptibility genes. Nineteen single nucleotide polymorphisms (SNPs) at 18 loci have been associated with breast cancer. We aimed to determine whether these predict breast cancer incidence in women with BRCA1/BRCA2 mutations. BRCA1/2 mutation carriers identified through the Manchester genetics centre between 1996 and 2011 were included. Using published odds ratios (OR) and risk allele frequencies, we calculated an overall breast cancer risk SNP score (OBRS) for each woman. The relationship between OBRS and age at breast cancer onset was investigated using the Cox proportional hazards model, and predictive ability assessed using Harrell's C concordance statistic. In BRCA1 mutation carriers we found no association between OBRS and age at breast cancer onset: OR for the lowest risk quintile compared to the highest was 1.20 (95% CI 0.82–1.75, Harrell's C = 0.54), but in BRCA2 mutation carriers the association was significant (OR for the lowest risk quintile relative to the highest was 0.47 (95% CI 0.33–0.69, Harrell's C = 0.59). The 18 validated breast cancer SNPs differentiate breast cancer risks between women with BRCA2 mutations, but not BRCA1. It may now be appropriate to use these SNPs to help women with BRCA2 mutations make maximally informed decisions about management options. 相似文献
5.
6.
Tobias Franiel René Aschenbach Sarah Trupp Thomas Lehmann Friedrich-Carl von Rundstedt Marc-Oliver Grimm Ulf Teichgräber 《Journal of vascular and interventional radiology : JVIR》2018,29(8):1127-1137
Purpose
To evaluate clinical outcomes and possible MR imaging predictors of clinical success after prostatic artery embolization (PAE) with 250-μm hydrogel particles.Materials and Methods
During a span of 1.5 years, 30 patients with moderate to severe lower urinary tract symptoms were included in a prospective, nonrandomized study. Embolization of at least one prostatic artery was considered as technical success. International Prostate Symptom Score (IPSS), quality of life (QOL), peak urinary flow rate (Qmax), residual urine volume, prostate volume, prostate-specific antigen level, and International Index of Erectile Function (IIEF) were recorded at baseline and at 1, 3, and 6 months after PAE. Multiparametric MR imaging was performed before PAE (n = 25) and 1 day (n = 25), 1 month (n = 7), 3 months (n = 7), and 6 months (n = 22) after intervention. A Wilcoxon–Mann–Whitney test was used to assess changes over time, and Spearman rank-correlation coefficient was used for outcome prediction.Results
PAE was technically successful in 90% of patients (n = 27). Clinical success (IPSS < 18 with decrease > 25% and QOL score < 4 with decrease ≥ 1 or Qmax ≥ 15 mL/s and increase of ≥ 3.0 mL/s) rates were 59% (16 of 27), 63% (17 of 27), and 74% (20 of 27) after 1, 3, and 6 mo, respectively. IIEF scores did not differ significantly during follow-up. The following adverse events occurred after PAE: urethral burning (5 of 27), fever (2 of 27), and urethral bleeding, rectal bleeding, cystitis, and penile burning sensation (1 of 27 each). No statistical correlations between initial multiparametric MR imaging changes and clinical parameters after 6 months were found (P values from .14 to .98).Conclusions
PAE with 250-μm hydrogel microspheres led to good clinical success after 6 months with a low complication rate. Significant MR imaging predictors of clinical success were not identified. 相似文献7.
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy. 相似文献
8.
The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases. 相似文献
9.