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61.
62.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
63.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
64.
Immunopathophysiological mechanisms in endometriosis-associated reproductive failure were studied in appropriate populations: infertile and fertile women with and without endometriosis. The incidence of sera positive for any of the autoantibodies tested among infertile women with endometriosis (n = 25) was similar to that observed in the three control groups [unexplained infertility patients (n = 25) and fertile women with (n = 10) and without (n = 25) endometriosis]. The mean volume of peritoneal fluid was significantly elevated in women with endometriosis (both fertile and infertile) as compared with patients without endometriosis (fertile or infertile). The concentration of peritoneal fluid leukocytes and the percentage of cells positive for macrophage markers were significantly increased and the percentage of T lymphocytes significantly decreased in infertile women with endometriosis but not in patients with unexplained infertility and fertile women with endometriosis, as compared with fertile controls without endometriosis. Macrophages from infertile patients with endometriosis had higher sperm phagocytosis than did those from infertile women without endometriosis or fertile subjects with or without endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic to the in-vitro development of 2-cell mouse embryos were significantly higher in infertile patients with endometriosis than in unexplained infertility patients and fertile women with or without endometriosis. It is concluded that immunological mechanisms of endometriosis-associated infertility exist but that these peritoneal immunological factors in infertile women with endometriosis are related to their subfertility rather than to the presence of ectopic endometrial implants. This is supported by the lack of immunological abnormalities observed among fertile women with endometriosis. These immunological abnormalities are lacking in patients with unexplained infertility.   相似文献   
65.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
66.
Leukemic cells from 32 cases of acute leukemia were cultured in vitro with the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) to study their differentiative potential. Three cases of acute undifferentiated leukemia (AUL) were studied intensively. We found that culturing of leukemic cells with TPA can induce changes in cell surface antigens. In particular, MCS-2, a "pan" granulocyte/monocyte marker, was inducible in vitro in AUL and in acute myelogenous leukemia, while it was not inducible in acute lymphoblastic leukemia. BA-2 (recognizing the Mr 24,000 protein) and TA-1 (recognizing the Mr 170,000 and Mr 95,000 proteins) were also inducible in cases of AUL, acute myelocytic leukemia, and acute monoblastic leukemia, although these antigens are not limited only to leukemias of the myelomonocytic lineage. Our studies also indicate that undifferentiated cells could be induced to nonspecific esterase and sometimes to chloroacetate esterase reactivity while losing terminal deoxynucleotidyl transferase. Morphological studies in these cases revealed cytological maturation following TPA treatment. In most cases, these changes were also partially inducible by culturing cells in medium alone or with the addition of dimethyl sulfoxide but not to the extent that was demonstrated by TPA. Our studies showed that MCS-2 is a very good, specific marker of acute nonlymphocytic leukemia. A potential use for TPA to aid in the subclassification of patients with AUL is also suggested.  相似文献   
67.
The vasa vasorum and angioplasty   总被引:2,自引:0,他引:2  
Interruption of flow in the vasa vasorum may lead to medial necrosis and aneurysm formation. The purpose of this study was to determine whether angioplasty produces significant alterations in the morphology or blood flow of the vasa vasorum of the dilated artery. The morphology of the canine vasa vasorum was studied before and after angioplasty; in a separate experiment vessel wall blood flow (VWBF) in canine carotid arteries was measured after angioplasty to determine whether physiologic regulation of the blood flow was disrupted by arterial dilation. No morphologic changes could be demonstrated in the vasa vasorum of the dilated artery; however, VWBF was increased by 1194 +/- 215% (mean +/- standard error, p less than 0.01) between 90 and 120 minutes after angioplasty. VWBF in the adjacent nondilated arterial segment was also increased (720 +/- 177% between 10-30 minutes, p less than 0.01) but returned toward normal after 60 minutes. Adenosine caused a "paradoxical" decrease in VWBF (p less than 0.05) of the dilated arterial segment while causing increased VWBF (p less than 0.05) in the thoracic aorta. Angioplasty appears to produce persistent hyperemia in the dilated arterial wall. A paradoxical response to adenosine suggests that vasa vasorum in the dilated arterial segment are maximally vasodilated. This may be due to mechanical disruption of vasomotor tone or to release of vasoactive substances.  相似文献   
68.
Gregg I 《Thorax》2000,55(9):807
  相似文献   
69.
The influence of reported paternal attitudes on the decision to breast-feed   总被引:1,自引:0,他引:1  
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions.  相似文献   
70.
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