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41.
In 224 patients, renal stones were removed from the urinary tract using either direct extraction with a basket or forceps (59 patients), ultrasonic lithotripsy (164 patients), or infusion chemotherapy (one patient). Residual stone fragments were present more frequently in patients treated with ultrasonic lithotripsy (27%) than with direct extraction (5%). Other complications included hemorrhage (eight patients), catheter dislodgement (four patients), large amounts of urine extravasation (three patients), glycine ascites (three patients), infection (two patients), pneumothorax (one patient), and a prolonged ileus (one patient). More complications occurred among the first 50 patients than the last 50 patients, even though more difficult cases, including patients with staghorn calculi, were accepted during the latter period. Although a learning curve exists, complications can be minimized by attempting to treat more favorable cases during the initial experience.  相似文献   
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Matrix metalloproteinases (MMPs) are involved in the regulation of the extracellular matrix (ECM) of the myocardium and thus the pathogenesis of vascular and cardiac hypertrophy. In this study, we investigated contribution of plasma matrix metalloproteinases to development of left ventricular hypertrophy (LVH) and diastolic dysfunction in hypertensive subjects. Hypertensive patients with (n = 27) and without LVH (n = 23) were included. All participants underwent a complete transthoracic echocardiographic examination, including recordings of the mitral annular early, late, systolic and diastolic velocities by Doppler imaging. Plasma concentrations of MMP-3 and MMP-9 were determined by the one-step sandwich enzyme immunoassay method. Plasma MMP-3 and MMP-9 concentrations were significantly higher in patients with LVH than those without LVH (2.4 +/- 1.2 vs 1.5 +/- 0.7 ng/ml, p = 0.006 and 5.2 +/- 2.8 vs 3.3 +/- 1.7 ng/ml, p = 0.003, respectively). MMP-3 and MMP-9 levels were also correlated with left ventricular posterior wall thickness and Doppler indices of diastolic dysfunction. Our findings have suggested that increased MMP levels may contribute to LVH and left ventricular diastolic dysfunction. Therefore, treatment of hypertension with MMP lowering drugs, such as angiotensin converting enzyme inhibitors and angiotensin receptor blockers, may have favorable effects on LVH and left ventricular diastolic dysfunction.  相似文献   
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BACKGROUND AND OBJECTIVES: Freckles (ephelides) are small, light brown macules of sun-exposed areas in fair-skinned subjects. On the other hand, freckle-like pigmentation of the axilla is a highly characteristic feature of neurofibromatosis. To what extent (clinically and pathologically) are the two pigmentary defects similar? And to what extent are café-au-lait patches and freckle-like lesions similar pathologically? SUBJECTS AND METHODS: Ten cases of neurofibromatosis and 10 cases of freckles were examined clinically. Two biopsies were taken from the former; one obtained from an axillary freckle-like lesion, and the other from a café-au-lait patch. One biopsy only was taken from freckles. The biopsies were processed for haematoxylin and eosin, silver stain and transmission electron microscopy. RESULTS: Obvious differences were detected between freckles (ephelides) and freckle-like lesions in cases of neurofibromatosis. Café-au-lait patches and freckle-like lesions showed the same pathological changes of lentigo simplex, with increased melanin pigment from the basal layer up to the stratum corneum, moderate elongation of the rete ridges and mild inflammatory infiltrate intermingled with melanophages. Electron microscopy revealed an increase in melanocyte number and the presence of giant melanin granules in freckle-like pigmentation as well as café-au-lait patches. These ultrastructural freckles (ephelides) showed an increase in activity but not the number of melanocytes. CONCLUSIONS: The term freckle-like should be changed to lentiginous macules of neurofibromatosis. On the other hand, the café-au-lait patches should be considered as lentiginous patches. Freckles should be restricted to sun-exposed areas in fair-skinned persons only.  相似文献   
46.
增效联磺片的体外溶出度和体内生物利用度   总被引:2,自引:0,他引:2  
邵俊  毛凤斐  屠锡德 《药学学报》1992,27(5):375-380
建立了测定体外溶出介质中磺胺嘧啶(SD)、磺胺甲噁唑(SMZ)和甲氧苄啶(TMP)及血浆中SD,SMZ,TMP和两个代谢产物N4-acetyl-SD和N4-acetyl-SMZ的反相高效液相色谱法,并对市售两种增效联磺片(片剂A和B)进行了体外溶出度和人体内生物利用度的研究。体外溶出度实验表明:两种片剂相同主药的T50差异非常显著(P<0.001),片剂A主药的溶出比B快。生物利用度试验表明:片剂B相对于A的口服吸收分数为0.73(SD),0.78(SMZ)和0.83(TMP),口服片剂后各主药的体内过程符合表观一级吸收和一级消除的单室模型。  相似文献   
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FF Wagner  ; WA Flegel 《Transfusion》1995,35(4):284-291
BACKGROUND: Transfusion-associated graft-versus-host disease (TA-GVHD) may occur in transfusions of blood from HLA-homozygous persons to HLA- heterozygous persons who share a haplotype. STUDY DESIGN AND METHODS: Two mathematical models were developed to calculate the upper and lower limit of the associated risks in various populations using a combination of serology- and DNA sequence-based HLA haplotype frequencies. RESULTS: For nondirected transfusion, the range of the estimated risk in United States whites is 1 of 17,700 to 39,000 (1/6,900-48,500 in Germans; 1/1,600-7,900 in Japanese). The risk in directed donation between parents and children is increased at least 21- fold for US whites, 18-fold for Germans, and 11-fold for Japanese. CONCLUSION: For nondirected transfusions, the estimates of TA-GVHD risk derived in this model are lower than estimates of previously published models, are in better agreement with the clinical experience, and explain in part the observed discrepancy between TA-GVHD incidence in the United States and that in Japan. Most notably for US whites, the relative increase in risk in directed transfusion is larger than previously thought.  相似文献   
49.
Two families with Emery-Dreifuss muscular dystrophy (EMD) are described. Several unusual features for EMD are emphasized. One of the patients had severe neuromuscular disability with inability to walk during early childhood. This patient also had mild bifacial paresis. His brothers had the typical slow progression of EMD. In some of the patients, muscle weakness distribution was more widespread than has usually been reported, with prominent involvement of finger extensors. It is suggested that there is a wide phenotypic spectrum in EMD. In both families, the disease segregated with markers spanning the EMD locus in Xq28. © 1993 John Wiley & Sons, Inc.  相似文献   
50.
In 1996, 24 920 AIDS cases were reported in the WHO European Region, bringing the cumulative total to 185 808 cases including 6969 (4%) paediatric cases (<13 years). For the first time since the start of the epidemic, the annual number of cases reported d  相似文献   
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