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1.
BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
2.
Microdialysis has been used to determine the concentration of salicylic acid in skin tissue and plasma periodically for 4 h to evaluate the effect of ointment bases on topical and transdermal delivery of salicylic acid. The ointment bases examined were solbase (water-soluble), poloid and white petrolatum (oleaginous), hydrophilic poloid (water in oil (w/o) type emulsion lacking water) and absorptive ointment (w/o-type emulsion containing water). The ointments (0.1 g) containing 25 μmol salicylic acid were applied for 2 h to the surface of rat skin (1 cm2) with (intact) or without the stratum corneum. For intact skin, the extent of topical delivery from different ointments, evaluated by the area under the concentration-time curve (AUC) of salicylic acid in the skin tissue (AUCskin), increased in the order solbase. white petrolatum, poloid, hydrophilic poloid. absorptive ointment. The ratio of AUCskin (topical delivery) to the AUC of salicylic acid in plasma (AUCplasma, transdermal delivery) varied remarkably among the different bases, the greatest ratio being observed for absorptive ointment. When the ointments were applied to skin surface without stratum corneum, AUCskin for solbase was much higher (about 45 times that for intact skin), whereas only a small (two-fold) increase was observed for poloid and hydrophilic poloid and the increase was negligible for white petrolatum and absorptive ointment. For skin without the stratum corneum, the ratio AUCskin/AUCplasma for the different ointments was comparable, although the magnitudes of AUCskin and AUCplasma still varied substantially. The variance of AUC values arises as a result of the different rates of release of salicylic acid from the bases. These results indicate that: the topical and transdermal delivery of salicylic acid in intact skin varies substantially among different ointment bases, and the greatest topical delivery is observed for absorptive ointment; use of absorptive ointment increases the retention of salicylic acid in the stratum corneum; and the stratum corneum functions strongly as a penetration barrier for solbase, moderately for poloid and hydrophilic poloid, and less for absorptive ointment and white petrolatum.  相似文献   
3.
Upper gastrointestinal endoscopy was performed in patients withrheumatoid arthritis (RA) during the period 1989–1991,and biopsy specimens were obtained from the stomach and fromthe duodenum for examining amyloid deposits. Among 407 patients,gastrointestinal amyloidosis was confirmed in 54 (13.3%). Twenty-twopatients were regarded as having slight amyloid deposits, while32 patients were categorized as having marked amyloid deposits.The incidence of clinical manifestations suggestive of systemicamyloidosis was more frequent in the marked deposits group thanin the slight deposits group (47% vs 14%, P < 0.05). Amongthe patients who died of manifestations associated with amyloidosis,the survival period following endoscopy was shorter in the markeddeposits group than in the slight deposits group. These findingssuggest that gastroduodenal biopsies may be useful for diagnosingsecondary amyloidosis and that the degree of amyloid depositsseems to be correlated with the clinical manifestations of RA. KEY WORDS: Rheumatoid arthritis, Complications, Secondary amyloidosis, Diagnosis, Endoscopy, Biopsy, Prognosis  相似文献   
4.
Various types of fibromatosis have been reported in infancy and early childhood. We describe an infant with diffuse fibromatosis on the scalp. A one year and five months-old girl showed a diffuse and hard mass 3 × 5 cm in diameter and no tenderness on the scalp. Two months later, the size of the mass had increased and several other tumors appeared on the lateral head. The magnetic resonance imaging (MRI) disclosed that a large and diffuse tumor had spread from the frontal to occipital head; a ‘helmet-like’ configuration of the tumor was exhibited on sagittal MR images. The tumor showed high signal intensity on T2-weighted images and was enhanced with Gd-DTPA. Histological examination showed a fibroblastic proliferation with intervening thick collagen bundles. The patient was diagnosed as having diffuse fibromatosis. The tumor at the resection site immediately recurred, whereas the tumor in the frontal head showed marked regression. Three months after the resection, new tumors appeared in the occipital head. The size and number of these tumors have remained unchanged for more than 18 months. The sites and appearance of the tumors were identical to that of juvenile hyaline fibromatosis (JHF) in this patient. However, JHF usually includes fibroblasts associated with large amounts of hyalinized collagen-like material, which were not present in our patient. The different histology of JHF comparing our case and other reported cases may depend on the different phase of the disease progression at resection. Long-term observation is necessary for the appropriate diagnosis and evaluation of prognosis in this patient.  相似文献   
5.
Two distinct hereditary defects, vitamin D-dependent rickets type I (VDDR I) and type II (VDDR II), have been recognized in vitamin D metabolism. VDDR I is suggested to be a deficiency of the renal 25-hydroxyvitamin D (25(OH)D)-1α-hydroxylase. Muscle weakness and rickets are the prominent clinical findings. A normal physiologic dose of 1α-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 is sufficient to maintain remission of rickets in this disorder. VDDR II consists of a spectrum of intracellular vitamin D receptor (VDR) defects and is characterized by the early onset of severe rickets and associated alopecia. This can be attributed to mutations in the VDR gene. Massive doses of vitamin D analogs and calcium supplementation is usually required for the treatment; however, the response to therapy is sometimes variable.  相似文献   
6.
Cholestatic hepatocellular carcinoma, which grows into the bile duct and causes obstructive jaundice, is rare and difficult to diagnose. A case is presented in which cholestatic hepatocellular carcinoma was detected by deposit of Lipiodol. This is also the first case that was successfully treated by endoscopic retrograde biliary drainage and transcatheter arterial embolization.  相似文献   
7.
Ruptured intracranial aneurysms are rare in the pediatric population compared to adults. This has incited considerable discussion on how to treat children with this condition. Here, we report a child with a ruptured saccular basilar artery aneurysm that was successfully treated with coil embolization. A 12-year-old boy with acute lymphoblastic leukemia and accompanying abdominal candidiasis after chemotherapy suddenly complained of a severe headache and suffered consciousness disturbance moments later. Computed tomography scans and cerebral angiography demonstrated acute hydrocephalus and subarachnoid hemorrhage caused by saccular basilar artery aneurysm rupture. External ventricular drainage was performed immediately. Because the patient was in severe condition and did not show remarkable signs of central nervous system infection in cerebrospinal fluid studies, we applied endovascular treatment for the ruptured saccular basilar artery aneurysm, which was successfully occluded with coils. The patient recovered without new neurological deficits after ventriculoperitoneal shunting. Recent reports indicate that both endovascular and microsurgical techniques can be used to effectively treat ruptured cerebral aneurysms in pediatric patients. A minimally invasive endovascular treatment was effective in the present case, but long-term follow-up will be necessary to confirm the efficiency of endovascular treatment for children with ruptured saccular basilar artery aneurysms.  相似文献   
8.
Altered intrahepatic pathway of para-umbilical vein in portal hypertension   总被引:2,自引:0,他引:2  
The object of this study was to determine the frequency and characteristics of altered paraumbilical vein in the hepatic parenchyma, developed from portal hypertension, using computed tomography (CT). Two hundred and ninety-two patients who presented with portal hypertension from 1986 to 1996 were studied retrospectively. The pathway of the dilated para-umbilical vein was demonstrated by contrast-enhanced CT. Thirty-one (11%) patients had a dilated para-umbilical vein arising from the left portal vein into the falciform ligament. In 24 (77%) of these patients, the para-umbilical vein followed the expected route, passing through the fissure of ligamentum teres hepatis. The remaining seven patients (23%) displayed the unusual pathway, with the vein arising from the left branch of the portal vein and passing into the hepatic parenchyma. In these seven patients, four had one collateral vein, and three patients had two collateral veins in the liver parenchyma. The dilated para-umbilical vein frequently passes through the hepatic parenchyma in patients with portal hypertension.  相似文献   
9.
BACKGROUND: We report our experience with Gas-less laparoscopy-assisted surgery (Gas-less LAS), hand-assisted laparoscopic surgery (HALS) and pure laparoscopic surgery (LS) for renal carcinoma and compare the characteristics and usefulness of these methods. METHODS: Seventeen, 14 and 16 patients were subjected to Gas-less LAS, HALS and LS, respectively. The study started with Gas-less LAS and then gradually shifted to HALS and LS. We evaluated the operative and postoperative parameters for each group. The learning curve effect was evaluated based on data from the first 10 cases of each group, which were operated on by the same surgeon and operation team. RESULTS: The learning curve of operation times in the LS group demonstrated that the operation time for this procedure is acceptable even in early-stage cases. Differences in mean operative time between the three surgical groups, excluding the conversion cases, were not statistically significant; however, there was a significant difference in blood loss volume between the groups (P 相似文献   
10.
Azoospermia is the most frequent cause of male infertility. After excluding the obvious urological reasons and the effect of Klinefelter's syndrome, azoospermia may be caused by an abnormality in the crucial gene(s) expressed during male germ cell differentiation. Recently, two candidate genes for azoospermia have been cloned from the azoospermic factor (AZF) locus on the Y chromosome long arm (Yq). One is YRRM (Y chromosome RNA recognition motif) gene, and the other is DAZ (deletion in azoospermia) gene. Both genes encode RNA binding protein and their expression is restricted to the testis. Therefore they are good candidates for AZF, although their function remains unclear. Here, the genes on the Y chromosome possibly involved in spermatogenesis and the role of the Y chromosome in evolution are discussed.  相似文献   
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