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排序方式: 共有231条查询结果,搜索用时 15 毫秒
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J A Sorenson C R Mitchell J D Armstrong H Mann D G Bragg F A Mann I B Tocino M M Wojtowycz 《Investigative radiology》1987,22(10):772-780
We evaluated the effects of unsharp masking and highly efficient scatter rejection on film-screen chest radiographs of cancer patients. Unsharp masking significantly improved the detectability of lung nodules and visibility of anatomic structures in poorly penetrated areas of the chest. Highly efficient scatter rejection by an improved antiscatter grid provided only modest additional benefits. The study supports the conclusion that nodule detection in poorly penetrated areas on conventional chest radiographs is limited primarily by display contrast, whereas in the well-penetrated lung fields it is limited primarily by confusing background structures, rather than inadequate contrast. A method for analyzing clinical nodule detection data by transforming the FROC data to ROC coordinates also is demonstrated. 相似文献
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LEE JS IM HH JUNG Y JUNG IS JANG JY CHUN YK CHO YD KIM JO CHO JY KIM YS SHIM CS & KIM BS 《Neurogastroenterology and motility》2006,18(6):493-494
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future. 相似文献
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IM Hann 《Journal of clinical pathology》1989,42(2):221-222
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Oocyte morphology predicts outcome of intracytoplasmic sperm injection 总被引:10,自引:14,他引:10
Serhal PF; Ranieri DM; Kinis A; Marchant S; Davies M; Khadum IM 《Human reproduction (Oxford, England)》1997,12(6):1267-1270
To examine the influence of cytoplasmic morphology on the success rate of
intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II
oocytes was assessed after cumulus stripping. The main abnormalities
detected were excessive granularity, cytoplasmic inclusions such as
vacuoles, smooth endoplasmic reticulum clustering and refractile bodies.
Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out
of 161 with excessive granularity and 112 out of 138 with cytoplasmic
inclusions. Very poor oocytes were not injected. No difference was found in
fertilization rate. The embryos achieved cleaved normally and a similar
number of good quality embryos among the three groups was noted. The
outcome of transfer of embryos derived solely from normal oocytes (group A:
72 patients, 183 embryos) was compared with those from oocytes with
cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A,
17 clinical pregnancies (24% per patient, implantation rate 10%) were
established. In group B, only one clinical pregnancy (3% per patient,
implantation rate 1%) was established, from the transfer of embryos derived
from oocytes with homogeneous granularity of the cytoplasm. No pregnancy
resulted following the transfer of embryos from eggs with cytoplasmic
inclusions. The difference was statistically significant. The outcome of
ICSI is dependent on the quality of the oocytes retrieved. Normal
fertilization and early embryo development were achieved in oocytes with
abnormal cytoplasm morphology, but the resulting embryos failed to
demonstrate the same implantation potential as those derived from oocytes
with normal cytoplasm.
相似文献
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Philpotts LE Lee CH Horvath LJ Lange RC Carter D Tocino I 《AJR. American journal of roentgenology》2000,175(4):1047-1050
OBJECTIVE. The purpose of this study was to determine the mammographic and histologic features of cancerous lesions underestimated using 11-gauge vacuum suction biopsy. MATERIALS AND METHODS. Retrospective review of 11-gauge vacuum suction biopsy was performed to identify lesions diagnosed as atypical ductal hyperplasia or carcinoma. The histology of the core and surgical specimens was compared. Of 158 cases of cancer, underestimation occurred in 15 (9.5%). The mammographic and histologic features were assessed. RESULTS. Of 15 underestimated cases, six were atypical ductal hyperplasia that proved to be cancer (5 ductal carcinoma in situ and 1 invasive) and nine were ductal carcinoma in situ that proved to have invasion. The underestimation rate for calcifications was 16.3% (14/86) and for masses was 1.6% (1/64) (p = 0.007). Most (5/6) underestimated atypical ductal hyperplasia cases were reported as "markedly atypical," and four of nine underestimated ductal carcinoma in situ cases were reported as "possible invasion." No significant difference was seen in the number of core specimens obtained or the sizes of the lesions for underestimated cases versus accurately diagnosed cases. The percentage of calcifications retrieved was significantly different (p = 0.017). No underestimations were found among cases in which the entire mammographic lesion was removed at vacuum suction biopsy. CONCLUSION. The cancer underestimation rate with vacuum suction biopsy was 9.5%. The underestimation rate for calcifications (16.3%) was significantly higher than that for masses (1.6%) (p = 0.007). The percentage of the lesion removed was an important factor in reducing underestimation, as reflected by the percentage of calcifications retrieved and the instances of complete resolution of the lesion seen on mammography. 相似文献
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