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71.
PURPOSE: To evaluate the effects of dissolvable collagen punctal plugs on the symptoms, tear stability and volume in aqueous deficient dry eyes. METHODS: Sixty-two aqueous deficient dry eye patients of mixed aetiology underwent lacrimal punctal occlusion with dissolvable collagen plugs. The subjects were randomly allocated to one of two treatment groups: group I (n = 36) had their lower puncta occluded and group II (n = 26) had both their upper and lower puncta occluded. The effectiveness of this treatment was clinically assessed by (1). scoring subject symptoms and (2). measuring the tear parameters of tear thinning time (TTT) and tear meniscus height (TMH) as indicators of tear stability and volume, respectively. Following baseline measurements, patients were reviewed at time intervals of 5 and 12 days post-occlusion. A group of age- and gender-matched normals (n = 45) was recruited for comparison (group III). RESULTS: Tear volume and stability were significantly higher in group III compared with I and II at baseline. In the treated groups on both days 5 and 12: (1). symptom score reduced significantly from a median value of 7 to 3 (p = <0.001); (2). tear stability increased significantly from a median value of 3 to 5 s by day 5 (p 相似文献   
72.
Purpose:  To determine the accuracy of distance autorefractions obtained by two 'open field' devices, the Tracey Visual Function Analyzer and the Shin-Nippon NVision-K 5001, by comparison with subjective refraction.
Methods:  Both eyes of 50 healthy phakic participants underwent subjective refraction. Autorefractions were then performed on undilated pupils using the Tracey and a modified Shin-Nippon autorefractor and these were repeated within 50 days. Agreement with subjective refraction was calculated for sphere, mean spherical equivalent (MSE) and cylindrical vectors J 0 and J 45. Intratest and intertest variability were also evaluated.
Results:  The mean age of the participants was 37.4 years. Subjective refraction MSE ranged from −6.25 D to +3.62 D, mean −0.49 D ± 1.79 D. Bias between subjective refraction and Tracey was −0.001 D, +0.045 D, +0.017 D, and −0.015 D for sphere, MSE, J 0 and J 45 respectively; these were not significant. Bias between subjective refraction and Shin-Nippon was +0.004 D, +0.033 D, +0.106 D, and −0.021 D; only the J 0 vector was significantly different ( p  < 0.0001) although this difference was small. Intratest variability for Tracey was low, measured at 0.189 D for sphere and 0.178 for MSE, and for the Shin-Nippon 0.099 D and 0.086 D respectively. Tracey intertest variability revealed small, statistically significant bias for sphere and MSE (+0.071 D and +0.070 D, p  = 0.011, 0.013). Shin-Nippon reproducibility showed no significant bias.
Conclusions:  Autorefraction measurements captured by both the Tracey and Shin-Nippon devices agree well with subjective refraction. The Shin-Nippon shows lower intratest variability.  相似文献   
73.
To identify the role of protein kinase C (PKC) isoforms in multidrug resistance in tumor cells, we examined the PKC isoform pattern in the multidrug resistant P388/ADR cell line and studied the effect of down regulation of PKC isoforms on intracellular daunorubicin accumulation and P-glycoprotein expression. Using monoclonal antibodies to PKC alpha, beta and gamma and flow cytometry technique we showed that P388/ADR cells overexpressed PKC alpha and beta as compared to drug sensitive P388 cells. Prolonged treatment of P388/ADR cells with phorbol myristate acetate (PMA), a procedure that is known to down regulate PKC, resulted in the down regulation of total PKC activity and the PKC beta isoform (at the protein level) that was accompanied by the correction of daunorubicin accumulation in P388/ADR cells. The level of expression of P-glycoprotein in PMA treated cells was similar to that of untreated cells. These results suggest that PKC beta regulates the drug efflux function of P-glycoprotein.  相似文献   
74.
Consequent to the promising results reported with 99mTc(V)-DMSA for imaging certain types of soft tissue tumors, we have developed methods to prepare this radiopharmaceutical in three ways: from freshly prepared reagents, through the use of a two component kit and use of the standard renal DMSA kit by a modified recipe. The 99mTc(V)-DMSA complex has been subjected to paper electrophoretic and chromatographic procedures and also biodistribution studies. The distinctly different behaviour of this new product compared to that of the well known renal DMSA complex has been clearly established. Scintiimaging in a preliminary clinical trial in patients with medullary carcinoma of the thyroid has been encouraging.  相似文献   
75.
Value of scintigraphic localization of obscure gastrointestinal bleeding.   总被引:1,自引:0,他引:1  
A total of 51 technetium-99m (99mTc)-labelled autologous red cell (LRC) scans performed on 49 patients for the localization of obscure gastrointestinal bleeding over a 5-year period was reviewed. The sensitivity for LRC scanning was 72.7% with a positive predictive value of 84.2%. Forty patients underwent both LRC scanning and visceral angiography during the same admission; angiography had a sensitivity of 38.9% compared with 66.7% for LRC scanning and the positive predictive values were 77.8% and 85.7%, respectively. Overall, the site of bleeding was located in 22 (45%) of 49 patients, but LRC scanning alone was successful in identifying the lesion in 16 (33%) cases. In patients who continue to bleed to the point of requiring operation, a combination of scintigraphy and angiography will localize a source in 70% of patients.  相似文献   
76.
DNA polymerase beta mutations in human colorectal cancer.   总被引:15,自引:0,他引:15  
L Wang  U Patel  L Ghosh  S Banerjee 《Cancer research》1992,52(17):4824-4827
Increasing numbers of alterations have been found in protooncogenes (e.g., ras, myc), as well as tumor suppressor genes (e.g., p53, Rb) in various types of tumors. The multiple mutations cannot be explained by the spontaneous mutation rate. It has been suggested that mutator phenotypes leading to the accumulation of these mutations may be required in the early stages of tumorigenesis. To test this hypothesis, the entire coding region of DNA polymerase beta, a repair enzyme, mRNA from colorectal tumors, and corresponding normal mucosa were amplified by polymerase chain reaction, cloned, and sequenced. Mutations in the catalytic domain of DNA polymerase beta were detected in colorectal tumor specimens compared to the normal colorectal mucosa, placenta, and blood samples. Since these mutations changed the structure of polymerase beta, it is expected that the efficiency of the DNA repair system would be impaired and thus may account for the high mutation rate observed in colorectal carcinomas.  相似文献   
77.
Summary Type 2 (non-insulin-dependent) diabetes is associated with the deposition of islet amyloid. The major formative peptide, islet amyloid polypeptide, has recently been characterised and an abnormality of the structure or expression of this gene is a possible candidate for the inherited component of Type 2 diabetes. A restriction fragment length polymorphism of the gene has been identified with Pvu II. To study the relationship between the islet amyloid polypeptide gene and Type 2 diabetes, two distinct genetic approaches have been undertaken. Firstly, non-linkage has been demonstrated in four pedigrees, with four normoglycaemic first degree relatives having an allele associated with diabetes in other family members, and one affected relative not having the putatively associated allele. The LOD score taking age-related penetrance into account was –1.68, making linkage unlikely (p=0.02). Secondly, in a population-based restriction fragment length polymorphism survey, no linkage disequilibrium of the alleles was found between a population of unrelated Caucasian subjects with Type 2 diabetes and a normal population. A mutation in or near the islet amyloid polypeptide gene is thus unlikely to be a common cause of Type 2 diabetes.  相似文献   
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80.
OBJECTIVE--To assess the efficacy and safety of a haemostatic bovine collagen plug (VasoSeal) in reducing patient immobilisation after cardiac catheterisation from a percutaneous femoral arterial approach. DESIGN--A non-randomised, prospective analysis of a new biodegradable haemostatic agent on an intention to treat basis. SETTING--The catheterisation suite of a regional cardiothoracic unit. PATIENTS--A series of 63 patients having various diagnostic investigations and therapeutic interventions agreed to participate in this study. INTERVENTIONS--Cardiac catheterisation was performed from a percutaneous femoral artery approach. Patients taking aspirin and those who required formal anticoagulation were not excluded. Patients were measured for the appropriate sized collagen delivery system at the beginning of the procedure. At the end of the procedure two bovine collagen plugs were applied to the surface of the femoral artery through the channel created by the application device. MAIN OUTCOME MEASURES--Incidence of successful delivery, insertion time, immediate outcome, inpatient complications, success of mobilisation of the patient at one and two hours after the procedure, and whether these variables relate to individual patient characteristics. RESULTS--Successful placement of the device was achieved in 57 of 63 consecutive patients (90.5%). The mean (SD) insertion time was 86 (24) seconds. Six (9.5%) patients did not receive the haemostat because of femoral artery perforation by the tissue dilator (n = 3), inability to compress the femoral artery proximal to the site of delivery (n = 1), pre-existing haematoma (n = 1), or patient withdrawal from the study (n = 1). Uncomplicated mobilisation within two hours of investigation was possible in 54 of 57 (94.7%) patients receiving this device. A sizeable haematoma (> 5 x 5 cm) prevented early mobilisation in the remaining three patients. Mobilisation was uncomplicated in 32 of 34 (94.1%) patients mobilised at two hours and 22 of 23 (95.6%) at one hour (NS). One patient who was mobilised early without complication later developed evidence of claudication in the treated leg. Femoral arteriography showed a smooth intraluminal filling defect attached to the wall of the femoral artery at the puncture site. This obstruction, presumed to be a collagen plug, was treated successfully with angioplasty. Sheath size, arterial pressure, the use of aspirin, heparin or warfarin, and body mass index did not influence patient outcome. The pattern of complications did not relate to a learning curve experience. CONCLUSIONS--The bovine collagen haemostat is a relatively safe and effective device that allows far earlier patient mobilisation than conventional haemostasis after diagnostic and therapeutic interventions from a percutaneous femoral artery approach. These results have important implications for patients undergoing investigation in mobile x ray units or in hospital based day case units.  相似文献   
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