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101.
Venous Dysfunction and the Change of Blood Viscosity During Head-Up Tilt   总被引:1,自引:0,他引:1  
The precise stimulus that induces vasovagal syncope is still unclear. We have previously demonstrated that the peripheral distribution of blood volume (venous pooling) is a strong predictor of tilt induced vasovagal reaction. We hypothesized that an increase in venous pooling during tilt accentuates the measured increase in blood viscosity. This hypothesis is based on the previously demonstrated increase in venous pressure and subsequent increase in transcapillary fluid transudation during tilt. The increased blood viscosity, in turn, increases vascular shear rate, which may alter the vasoconstrictive and other cardiovascular responses to decreased preload. We measured blood viscosity (supine and tilt) in 56 patients with a history of orthostatic intolerance (37 with venous pooling [VP] and 19 without venous pooling [non-VP]). VP and non-VP were separated into subgroups based on blood pressure and heart rate response to tilt. There was a positive correlation between blood viscosity and plasma aldosterone in the supine. In the group as a whole, neither supine blood viscosity nor its increase during tilt differed between VP and non-VP. However, the tilt induced increase of blood viscosity was significant only in patients with tilt provoked tachycardia plus normal blood pressure response in VP group. We suggest that the increase of blood viscosity in this group led to the normal blood pressure response. The positive correlation between supine blood viscosity and supine plasma aldosterone indicates that the normal blood pressure response in this group possibly was via stimulation of the renin-angiotensin-aldosterone system.  相似文献   
102.
To assess the effects of right ventricular (RV) pacing on body surface QRST distributions, we recorded QRST isointegral mops (I-maps) during sinus rhythm and RV pacing in 25 patients with anterior myocardial infarction (MI), 19 with inferior MI, and 14 without MI. The QRST values at each lead point recorded during sinus rhythm and RV pacing with an 87-lead system were analyzed with a paired t-test in each patient. An abnormal decrease in the QRST value of the I-map was assessed by the difference map, which indicated a −"2SD area," where the QRST integral value was less than the normal range (mean – 2SD) caiculated from 608 normal individuais. The I-maps were similar during the two activation sequences in patients with and without MI. However, during RV pacing, QHST values significantly decreased over the upper right anterior chest and increased over the lower left anterior chest and back. The ΣDMs (sum of QRST integral vaiues beiow the normal range) for both activation sequences were strongly correlated in patienis with anterior MI and with inferior MI (r = 0.91 and r = 0.92, respectively; P < 0.001). Although small but significant changes in QRST values were detected, the distribution of the "-2SD area" and the ΣDM were similar during both activation sequences in patients with prior MI. Thus, these findings demonstrate that an altered activation sequence produces small but significant changes in QRST values but that I-maps still provide information that is useful for the diagnosis of MI during RV pacing.  相似文献   
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Seminal vesicle cysts are uncommon abnormalities in the pelvis. The case of a seminal vesicle cyst that extended through the inguinal canal is reported. A 35-year-old man presented with left inguinal swelling. He was diagnosed with a left inguinal hernia. However, the interpretative diagnosis was a spermatic cord tumor. The operation was changed to tumor resection. The tumor existed along with the vas deferens from part of the parietal peritoneum outside the inguinal tunnel to the deep pelvic space. The cylinder-shaped tumor was 3 cm in diameter and 20 cm long. Pathological examination revealed a seminal vesicle cyst that extended through the inguinal canal. To the best of our knowledge, this is the first case report of a seminal vesicle cyst inguinal hernia.  相似文献   
105.
A single-crystal X-ray diffraction analysis has been made of the structure of the cyclic octapeptide cyclo(l -Pro-Sar)4. The material [C32H48O8N8 · (21/4) H2O° (1/2) CH3OH, Mr = 799.43] crystallizes in the monoclinic space group C2 with cell dimensions a = 14.544 (3), b = 11.902 (2), c = 14.064 (3), and β = 122.26 (2)° (Λ = 1.54178 Å, T = 293 K). The final R value for the 1980 observed reflections is 0.079. The ring conformation has the peptide bond sequences of cis-cis-trans-trans-cis-cis-trans-trans (Pro-Sar-Pro peptide bond linkages are cis-cis -or trans-trans). The pyrrolidine rings in the four proline residues take an envelope form in which the γ-carbon atom deviates from the plane of the remaining four atoms in the ring.  相似文献   
106.
Lymphangioma of the kidney   总被引:4,自引:0,他引:4  
Lymphangiomas are rare benign tumors that are congenital malformations of the lymphatic system. Most cases present in children as a soft, cystic mass in the neck and the axilla. Primary renal lymphangioma is exceedingly rare, with only 35 cases reported so far. We report a case of primary lymphangioma arising from the kidney. A 59-year-old man was referred for evaluation of a right renal mass found in an abdominal ultrasonography during a health checkup. Abdominal ultrasonography and computed tomography (CT) revealed a 3.2 x 2.9 cm multiloculated cystic mass in the upper pole of the right kidney. We could not deny malignant disease such as cystic renal cell carcinoma with any diagnostic modalities. The patient was brought to surgery. During the surgical procedure, the tumor was suspected to be lymphangioma of the kidney as a result of a frozen- section histopathological evaluation. Therefore enucleation of the tumor was performed. Pathological evaluation of the specimen revealed lymphangioma arising from the kidney. The patient is free of disease after a 3-month follow-up period.  相似文献   
107.
OBJECTIVES: Most of our knowledge concerning renal obstruction has been derived from experimental animal models, and it is not yet well defined in spontaneous hydronephrosis. The aim of our study is to evaluate the roles of transforming growth factor-beta1 (TGF-beta1) and apoptosis in congenital hydronephrotic kidneys in comparison with experimental models. METHODS: We made histological studies on kidneys from 6-week-old Wistar-Imamichi rats with congenital unilateral hydronephrosis as well as surgical models of complete or partial unilateral ureteral obstruction. The severity of hydronephrotic kidneys was evaluated on routine hematoxylin and eosin (H&E) stained sections, and the tubulointerstitial fibrosis analyzed morphometrically on Masson's trichrome stained sections. Renal tubular atrophy was assessed on periodic acid Schiff (PAS) stained sections, and tubular cell apoptosis assessed with TUNEL technique. The renal TGF-beta1 level was determined by a sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS: We observed a significant loss of kidney weight with profound compensatory growth of the contralateral kidney in rats with congenital hydronephrosis. Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, renal parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. The renal TGF-beta1 level was markedly elevated in hydronephrotic kidneys as compared with normal controls (326.01 +/- 30.64 pg/mg protein vs 227.81 +/- 11.07 pg/mg protein, P < 0.01). The tubular apoptotic score in hydronephrotic kidneys was also significantly higher than normal controls (2.17 +/- 0.50/HPF [high power field]vs 0.14 +/- 0.04/HPF, P < 0.01). The increased TGF-beta1 and apoptotic status paralleled the histological changes of tubulointerstitial fibrosis and tubular atrophy. Similar findings were also obtained in experimental obstructive models. CONCLUSION: In comparison with surgical models of partial and complete ureteral obstruction, our data provide solid morphological and molecular evidences of renal obstruction in rats with congenital hydronephrosis.  相似文献   
108.
Cyclic octapeptide, cyclo[Gly-L-Lys(Z)-Sar-L-Pro]2 (CGLSP2) was synthesized as an ionophore model. Its ion-transport ability through a liquid membrane was investigated in connection with ion extractability and conformational properties. CGLSP2 transported the picrate salts of Ba2+ and Ca2+ efficiently through chloroform membrane in a U-tube (Ba2+> Ca2+ > K+ > Rb+ > Mg2+> Na+). Cyclo[Gly-L-Lys(Z)-Sar-L-Pro] or Boc-[Gly-L-Lys(Z)-Sar-L-Pro]n-OR (n = 1 or 2; R = H or CH3) showed a significant decrease in ion-transport ability. Extraction equilibrium constants (Kex) of CGLSP2 with metal picrates were determined in chloroform-water system. In this case, CGLSP2/cation complexes were found to have a stoichiometry of 1:1. The Kex sequences were Ba2+ > Ca2+ > Mg2+ and K+ > Rb+ > Na+, showing good agreement with the selectivity in ion transport. Conformation of CGLSP2 in chloroform (CDC13) was investigated by 1H and 13C-n.m.r. spectroscopy. Predominant conformation takes a C2 -symmetric structure containing two cis Lys-Sar peptide bonds. Upon complexation with Ca2+ in CDC13/CD3CN mixture (5/3, v/v), the conformation of CGLSP2 converged into a single C2 -symmetric one that was predominant in a free state in CDC13.  相似文献   
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