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41.
JP Wei  GJ Burke 《Canadian Metallurgical Quarterly》1997,63(12):1097-100; discussion 1100-1
Tc-99m-sestamibi has been shown to localize parathyroid adenomas effectively, but controversy continues as to the use of this scan before initial surgery for primary hyperparathyroidism. We analyzed the cost utility of obtaining this study before initial surgery for primary hyperparathyroidism. Twenty-two consecutive patients with primary hyperparathyroidism underwent dual-phase Tc-99m-sestamibi scan before initial bilateral neck exploration. Surgical findings were correlated with the results of sestamibi scan. There were 15 women and 7 men, with a mean age of 50.5 years (range, 22-76). Preoperative mean total calcium was 11.74 mg/dL (range, 10-15), ionized calcium was 6.19 mg/dL (range, 5.2-7.7), and intact parathyroid hormone was 153.5 pg/mL (range, 83.1-551). Postoperative mean ionized calcium was 4.56 mg/dL (range, 4.1-5.57). Twenty sestamibi scans had a positive localization, and 2 scans had no localization. At surgery, 18 solitary adenomas, 3 diffuse hyperplasias, and 1 patient with four normal parathyroid glands were found. Sixteen sestamibi scans were true positive (solitary adenoma), 4 scans were false positive (2 diffuse hyperplasia, 1 wrong side, and 1 lymph node), 1 negative scan was true negative (diffuse hyperplasia), and 1 negative scan was false negative (adenoma). One patient (four normal glands) at the second operation had a supernumerary fifth gland adenoma excised from the mediastinum. Preoperative Tc-99m-sestamibi scan did not offer any advantage when a complete bilateral neck exploration is performed. Sixteen of (84%) adenomas were correctly localized, but 18 of 19 adenomas were in the neck and were easily found. The 1 ectopic adenoma was not found by scanning or with initial surgery. The 4 of 22 (18%) false-positive localizations and the 2 of 22 (9%) negative scans contributed nothing to the surgery. Of the 22 localizing sestamibi scans, surgery was not altered to affect the outcome. At a cost of $550 per sestamibi scan and with the error inherent in the scan, it is not cost effective to obtain Tc-99m-sestamibi scan before initial surgery for primary hyperparathyroidism.  相似文献   
42.
Agenesis of the corpus callosum in a mother and son   总被引:1,自引:0,他引:1  
Most reported familial cases of agenesis of the corpus callosum have followed either an autosomal recessive or an X-linked recessive pattern of inheritance. To the best of our knowledge, there is only one previous report of a family showing clear-cut autosomal dominant inheritance. We present the second such family, among whom a mother and her son had moderately severe coordination problems and low-normal intelligence. We suggest that agenesis of the corpus callosum, when transmitted as an autosomal dominant trait, is clinically characterized by a relatively milder phenotype than that occurring when inheritance is either autosomal or X-linked recessive and may be more common than has been thought.  相似文献   
43.
We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE. Thus, the age-dependent and coordinate diminution in cell proliferative activity and cell death events may serve to maintain the thickness of the OE as mice mature and age.  相似文献   
44.
In the preceding paper (Latham, G. J., Bacheller, D. J., Pietroni, P. , and von Hippel, P. H. (1997) J. Biol. Chem. 272, 31677-31684), we demonstrated that the T4 gp44/62-ATP clamp loader binds to the C-terminal face of the gp45 sliding clamp. Here we extend these results by exploring the structural relationship between the gp43 polymerase and the gp45 sliding clamp. Using fluorescence intensity and polarization techniques, as well as photo-cross-linking methods, we present evidence that gp43, like gp44/62, binds to the C-terminal face of gp45. In addition, we show that g43 binds to the gp45 clamp in two distinct interaction modes, depending on the presence or absence of template-primer DNA. When template-primer DNA is present, gp43 binds tightly to gp45 to form the highly processive DNA polymerase holoenzyme. Gp43 also binds to gp45 in the absence of template-primer DNA, but this interaction is more than 100 times weaker than gp43-gp45 binding on DNA. Specific interactions between gp43 and the C-terminal face of gp45 are maintained in both modes of binding. These results underscore the pivotal role of template-primer DNA in modulating the strength of protein-protein interactions during DNA synthesis and provide additional insight into the structural requirements of the replication process.  相似文献   
45.
PSA-based screening substantially increases the prostate cancer detection rate and the percentage of organ-confined tumors. It appears that there is some benefit from screening for prostate cancer because of the increased amount of potentially curable disease discovered and the fact that 96% of the pathologically staged tumors detected have histologic features associated with aggressive cancer. Additional evidence that nearly all tumors detected on the basis of initial PSA screening are apt to be clinically significant may be derived from the information that PSA-based screening decreases the incidence of incidental A1 grade III and A2 tumors but does not increase the detection of clinically insignificant A1 grade I and II tumors. At this time, PSA represents the most effective and valuable tool to detect early prostate cancer; therefore, PSA should be used to improve early diagnosis of prostate cancer. Some advances have been made with the introduction of age-specific reference ranges and the ability to measure free to total PSA ratios. The data presented support the clinical usefulness of age-specific reference ranges for serum PSA. Calculation of the free to total PSA ratio is valuable in deciding which screening volunteers require further evaluation, increases the specificity of PSA screening, and as demonstrated may be useful in deciding which patients with isolated PIN should undergo repeat biopsies. Based on these facts, PSA truly can be described as the most important and useful marker for adenocarcinoma of the prostate. Based on these encouraging results and the obligingness of the social insurances, we will be able to continue PSA screening for early detection of prostate cancer for all concerned Tyrolean men in the future.  相似文献   
46.
The year 1996 was the 21st birthday of the Australian and New Zealand Annual Scientific Meeting on Intensive Care. With this maturity many of the issues that were so troublesome to intensive care in the early years relating to identity, training, recognition, and standards have largely resolved. There are, however, no signs of complacency. We need to improve the image of a career in intensive care to trainees, expand research opportunities, and respond to the ever-changing challenges coming from administrative reorganization, budgeting constraints, and increasing public expectations. I believe the foundations have been well laid to ensure a continuing contribution by Australian and New Zealand intensivists to clinical intensive care, their hospitals, ANZICS, and a place in the global research effort in intensive care.  相似文献   
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OBJECTIVE: To determine effect of electrical muscle stimulation (EMS) on rate and degree of return to function of the limb and development of degenerative joint disease (DJD) after surgical creation and subsequent stabilization of the cranial cruciate ligament (CrCL)-deficient stifle. ANIMALS: 12 clinically normal adult large (19.5 to 31.5 kg) dogs. PROCEDURE: Dogs were anesthetized, and the right CrCL was severed via arthrotomy, destabilizing the stifle. After 3 weeks, the stifle was surgically stabilized. Three weeks later, 6 dogs were subjected to an EMS treatment protocol for the thigh muscles. At 5, 9, 13, and 19 weeks after stifle destabilization, treated (n = 6) and control (n = 6) dogs were evaluated for return of stifle function. Gross and histologic evaluations of the stifles were performed at 19 weeks after stifle destabilization. RESULTS: Treated dogs had significantly (P = 0.001) better lameness score than did control dogs. There was less palpable crepitation of the stifle in treated dogs (P = 0.06); treated dogs also had significantly (P = 0.01) fewer radiographic signs of bone changes. Thigh circumference was significantly (P = 0.02) larger in treated dogs. There was less gross cartilage damage (P = 0.07) in the EMS-treated dogs, but more medial meniscal damage (P = 0.058, cranial pole; P = 0.051, caudal pole). CONCLUSIONS: Improved lameness scores, larger thigh circumference, and decreased radiographically apparent bony changes observed for the treated group of dogs support the hypothesis that dogs treated by EMS after surgical stabilization of the CrCL-deficient stifle had improved limb function, with less DJD, than did dogs treated with the currently accepted clinical protocol of cage rest and slow return to normal activity. However, results of force plate evaluation did not support the hypothesis. Increased meniscal damage in dogs treated by EMS may be cause for concern.  相似文献   
50.
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