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991.
992.
The healing process of vertebral fracture was investigated in 37 senile osteoporotic patients on serial magnetic resonance imagings (MRIs), including enhancement study with gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA). The healing process was classified retrospectively into six categories in terms of the changes and recovery of T1 and T2 signal intensity and in terms of the local vascularity. Two types of damage foci were identified, and, in each type, three patterns of healing were noted. In the partial collapse type, the focus of damage in the fractured vertebral body was located near the cranial or caudal endplates; in the total collapse type, the focus was located at the center of the body. In each of these two types, fracture healing was smooth, belated, or resulted in nonunion. In the partial collapse type, vertebral fractures healed smoothly (smooth pattern) in 8 cases, belatedly (belated pattern) in 11, and resulted in nonunion (nonunion pattern) in 5. In the total collapse type, vertebral fractures healed smoothly (smooth pattern) in 6 cases, belatedly (belated pattern) in 4, and resulted in nonunion (nonunion pattern) in 3. The percent height of the anterior wall, central portion, and posterior wall was defined to allow accurate calculatation of the collapse of the fractured vertebral body. Chronological changes in the vertebral body height were investigated. Progressive collapse of the vertebral body was minimal in the smooth pattern cases, and most severe in the nonunion pattern cases. Statistical analysis indicated that prediction of the course of the fracture was difficult only with the height of the fractured vertebral body in acute phase. Enhancement study with Gd-DTPA showed that, in fractures with favorable prognosis, the ischemic area in the body tended to be smaller from the beginning, and restoration of vascularity was prompt. On the contrary, in fractures with unfavorable prognosis, the ischemic area was wider, and restoration of vascularity was poor.  相似文献   
993.
994.
We measured bone mineral density (BMD) in the radius by dual energy X-ray absorptiometry in 34 patients with rheumatoid arthritis (RA) and in 40 healthy controls. The BMD in RA patients in their fifties and sixties, but not in their forties and seventies, was significantly lower than that in the control subjects. The decrease in total radial BMD correlated with grip strength, RA activity and RA stage. The de crease in distal radial BMD correlated with RA activity, but not with grip strength. The levels of serum parathyroid hormone, alkaline phosphatase, and urinary hydroxyproline/creatinine were significantly higher in the patients. From these findings, we suggest that the bone loss in RA patients is affected by severity of inflammation, disuse, postmenopausal osteoporosis and secondary hyperparathyroidism.  相似文献   
995.
Summary. In order to ensure fertility, mammalian spermatozoa have to undergo acrosome reaction, the most obvious morphological change during this being the exposure of the inner acrosomal membrane. In the present study, the acrosome-reacted human spermatozoa were successfully separated without loss of viability by using cell affinity chromatography on Concanavalin A (Con A) Sepharose. Con A demonstrated affinity for both the intact and the acrosome-reacted spermatozoa regardless of their viability; the latter, however, gave higher affinity than the former against Con A. Prior to the column chromatography, the immotile spermatozoa and the seminal plasma were excluded by means of a modified swim-down procedure and the resulting spermatozoa were subsequently immobilized by slow rate cooling in ice-cold water. Cell affinity chromatography was performed at 4 °C. To prevent mechanical trapping of the spermatozoa among the packed gel beads, the column was interconnected with a reservoir, the vertical drive of which was allowed to lose the gel bed and thereby release the trapped spermatozoa. Stepwise competitive elution with 5.0 μM mannose and 25% heat-inactivated human serum was capable of separating the intact spermatozoa and the acrosome-reacted spermatozoa from each other. The acrosome reaction rate of sperm fraction which was adsorbed to Con A Sepharose and eluted with 25% serum was found to be 83±2.3%, and motility and viability of these fractions were measured to be 80±6.3% and 83±7.6%, respectively ( n = 8, mean±SD). The status of the acrosome in a final preparation (motility 92%, acrosome reaction rate 88%) was observed by scanning electron microscopy, and 81% spermatozoa lost their acrosome cap.
Acrosome-reacted spermatozoa—  相似文献   
996.
We retrospectively studied the incidence of difficult laryngoscopy in 53 subjects with obstructive sleep apnea syndrome (OSAS) undergoing uvulopalatopharyngoplasty (UPPP) and 72 subjects with chronic otitis media undergoing tympanoplasty (control group). The incidence of difficult laryngoscopy in the UPPP group was significantly higher than in the control group (18.9%vs 4.2%,P<0.001). To analyze the anatomical findings of difficult laryngoscopy in UPPP patients, cephalometric roentgenograms were compared between patients in whom direct laryngoscopy was difficult (difficult patients,n=10) and patients in whom direct laryngoscopy was not difficult (nondifficult patients,n=43). Cephalometric atlanto-occipital distance (cAOD) was less than 4mm in 80% of the difficult patients, and there were significant differences between the difficult patients and the nondifficult patients (2.8±3.3 mmvs 6.7±3.0 mm, mean ±SD,P<0.001). There were significant differences in cephalometric effective mandibular length/cephalometric posterior depth of mandible ratio (cEML/cPDM) between the difficult patients and the nondifficult patients (4.0±0.6vs 4.5 ±0.8,P<0.01); however, the calculation of cEML/cPDM was more difficult than cAOD. We concluded that OSAS patients undergoing UPPP are at high risk for difficult laryngoscopy, and that cAOD calculated from cephalometric roentgenograms is an easy and sensitive predictive indicator for the estimation of difficult laryngoscopy.  相似文献   
997.
998.
A case of primary myelofibrosis complicated with pericardial effusion and proteinuria is described. A 66-year-old female was admitted to our hospital because of abdominal fullness and shortness of breath. On admission, hepatosplenomegaly and pericardial effusion were observed. Blood examination revealed leukoerythroblastic anemia and thrombocytosis with tear drop cells and giant platelets. Bone marrow aspiration was dry tap and its biopsy showed remarkable myelofibrosis. Urinalysis indicated severe proteinuria. Although neutrophilic alkaline phosphatase score was low, no signs of acute blastic crisis of chronic myelogenous leukemia was found. The diagnosis of an atypical type of primary myelofibrosis was obtained. Administration of MCNU was started in August 1987. Hepatosplenomegaly, pericardial effusion and proteinuria were gradually improved after the administration. The etiology of the pericardial effusion and proteinuria were not obvious, however, these facts suggest that these abnormal findings might be related to PMF itself and MCNU was effective to PNF.  相似文献   
999.
1000.
We describe a patient with severely diseased ascending aorta and small internal mammary arteries, who underwent off-pump coronary artery bypass to the left anterior descending coronary artery and right coronary artery using composite arterial grafts consisting of the pedicled proximal internal mammary artery and interposed radial artery graft. The interposed radial artery graft provides advantages, such as making coronary anastomosis on the beating heart easier and to increasing the flow potentiality of the internal mammary artery.  相似文献   
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