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101.
A prospective study was designed to assess the value of scrotal ultrasound in the diagnosis of testicular neoplasm. Comparison of findings yielded by ultrasound with those made on surgical exploration of the scrotal contents in 56 patients showed a sensitivity of 94.6%, specificity of 57.9% and an overall accuracy of ultrasound of 82.1%. While capable of distinguishing intra-from extratesticular structure, scrotal ultrasound is not specific enough to differentiate a tumour from benign diseases involving testicular parenchyma. Still, it may add new information to the clinical examination of the scrotum, and reduce the number of probatory surgical procedures in patients with the finding of an intrascrotal mass. This paper describes the ultrasound pictures of a normal testis, testicular tumours and extratesticular disease that are most often considered in the differential diagnosis of testicular tumours.  相似文献   
102.
Ileal and jejunal resections were carried out to investigate their effect on the faecal bile acid excretion and on the development of 1,2-dimethylhydrazine (DMH)-induced colonic cancer in rats. Both resection types raise the total daily faecal bile acid level compared to the control sham-operated group, whereas ileal resection has a more pronounced effect. The incidence of tumours was found higher in groups with enhanced faecal bile acid level. Our findings show a connection between the daily faecal bile acid excretion and the incidence of DMH-induced colonic cancer.  相似文献   
103.
Forty-five patients with mild hypertension were treated for 2 months with either metoprolol or pindolol in a randomized, blind, crossover study. The effects of metoprolol (100-300 mg/day) and pindolol (5-15 mg/day) on triglyceride (TG), cholesterol (C), high-density lipoprotein cholesterol (HDL-C), and HDL subfraction (HDL2-C and HDL3-C) levels were compared in males and females separately. Pindolol and metoprolol significantly elevated (10% above baseline level) the plasma TG level in both males and females. After metoprolol treatment, the HDL-C level remained unchanged in both sexes; however, a shift was found between HDL2-C and HDL3-C:HDL2-C decreased and a concomitant elevation in HDL3-C was observed. Pindolol significantly decreased total C, HDL-C, and HDL2-C levels in males. A similar trend (although the changes were not significant) was found in females. The results demonstrate the role of beta blockers in the inhibition of TG-rich lipoprotein elimination. These findings suggest that during long-term administration of metoprolol and pindolol, risks and benefits from beta-blocker therapy must be carefully considered. Continuous monitoring of lipid profiles is suggested during this treatment in order to avoid the potential worsening effect of beta blockers on risk factors of ischemic heart disease.  相似文献   
104.
105.
The model of biliary tract infection induced in rats given suspension of E. coli into the bile duct is described. To prevent leakage of microorganisms after the administration, a temporary ligation of the bile duct followed. Contemporary groups of sham-operated and control rats (given saline by intrabiliary injection) were compared to assess the significance of the changes. The effect of biliary infection was concentration dependent. If 0.1 ml of the concentration containing 10(2), 10(3) and 10(6) colony-forming units/ml was injected, the mortality of rats reached 8%, 57% and 65%, respectively within 24 h. Blood and bile cultures from all dead animals grew E. coli. To evaluate the effect of chronic biliary infection, the concentration of 10(2) colony-forming units/ml was used. Serum concentrations of total and conjugated bilirubin, cholesterol and creatinine, activities of S-alanine-aminotransferase, S-aspartate-aminotransferase, alkaline phosphatase, the count of leucocytes in blood, total body weight with weight of the liver were investigated on days 1, 4 and 12 after the treatment. The results showed: an increase in leucocytes (21 +/- 4.2 10(9)/l, p less than 0.02 vs control animals) on day 4, an augmentation of serum cholesterol on day 1, (2.1 +/- 0.9 mmol/l, p less than 0.02 vs control animals), the presence of E. coli in blood on day 1 and its persistence in the bile on days 1, 4 and 12. Except the bile, all of the other symptoms were reversible by day 12.  相似文献   
106.
To investigate the possible use of a biodegradable microporous synthetic tube for fallopian tube replacement, polyetherurethane/poly-L-lactide (PU/PLLA) grafts in the uterine horn of the rat were studied and their patency and healing characteristics compared with those of nonbiodegradable polytetrafluoroethylene (PTFE; Teflon) grafts as well as with those of reanastomosed uterine horns. Regarding the healing characteristics, the PU/PLLA grafts were superior to the PTFE graft, as was indicated by the regeneration of endometrium and the extensive perigraft tissue ingrowth. However, the graft/uterine anastomoses of the PU/PLLA and PTFE grafts became obstructed by a plug of mucosal folds, all reanastomosed, uterine horns in the control experiments remaining open. In conclusion, although biodegradable microporous PU/PLLA uterine horn grafts have better healing characteristics than PTFE grafts, they easily obstruct at the graft/uterine junction. Mucosal suturing and/or the use of splints may contribute to the feasibility of biodegradable microporous artificial fallopian tubes in tubal surgery.  相似文献   
107.
An alteration in cell/matrix interactions is one of the suggested mechanisms leading to cyst formation in polycystic kidney diseases. Most of these interactions are mediated by β1-integrins, a subfamily of integrin receptors, formed by the association of the β1-chain with different α-subunits. To date, no study on α-integrin subunit distribution during the early stages of cyst development has been reported. Using immunofluorescence, we analyzed the distribution of α-integrin subunits (α1, α2, α3, α5, and α6) and basement membrane proteins in kidneys of fetuses with autosomal dominant (ADPKD) or autosomal recessive polycystic kidney disease (ARPKD). The distribution was compared with that observed in normal fetal and post-natal kidneys, and in fetal cystic dysplasia and Meckel syndrome. Marked increase in α1-integrin staining was observed in normal and cystic collecting duct cells of both polycystic diseases (PKD), compared with normal and cystic controls. The distribution of integrin subunits α2, α3, and α6 was irregular in cyst epithelial cells of PKD and cystic controls. The increased expression of the α1-subunit specifically observed in PKD collecting duct cells may be an early consequence of the genetic defect in ARPKD. In ADPKD it parallels the reported expression of polycystin, the protein product of PKD1. The irregular expression of α2, α3, and α6 integrin subunits observed in all types of cysts suggests that cell/matrix interactions are altered early and may participate in the development of cysts, perhaps by contributing to the deregulation of cell survival in cystic diseases. Received May 28, 1996; received in revised form October 2, 1996; accepted October 25, 1996  相似文献   
108.
Cumulative dose-response curves were constructed from evoked compound electromyographic (EMG) recordings in man to compare the sensitivity to pancuronium of the adductor pollicis, the hypothenar and the first dorsal interosseous muscles. Also, the EMG and mechanomyography-based sensitivity of the adductor pollicis muscle were compared. The EMG and the mechanomyogram were evaluated in random sequence in each of 21 adult thiopental, fentanyl and diazepam anesthetized patients. The EMG-based ED50 were 36-38 micrograms.kg-1 with no differences between muscles. The EMG-based ED90 of the adductor pollicis and the hypothenar muscles were 62-65 micrograms.kg-1 compared to the 60 micrograms.kg-1 of the first dorsal interosseous muscle (P < 0.05). ED50 (34 micrograms.kg-1), and ED90 (56 micrograms.kg-1) obtained from the adductor pollicis mechanomyogram were significantly lower than those based on the EMG (P < 0.05). It is concluded that differences in sensitivity to pancuronium exist between the three muscles when evaluated from the EMG, and that the apparent sensitivity of a given muscle to a muscle relaxant may depend upon whether the response is evaluated using EMG or mechanomyography.  相似文献   
109.
L T?r?k  I Borka  G Szabó 《Orvosi hetilap》1992,133(2):101-103
A Waldenstr?m macroglobulinemia case, manifested in the form of non-specific skin-symptoms (cold urticaria and cold purpura) is described in a 37 years old female patient. As new skin-symptoms progressive telangiectasia and naevi aranei could be observed. Involvement of skin may be explained by macroglobulins with kryoprotein properties, making early diagnosis possible at the same time.  相似文献   
110.
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid.  相似文献   
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