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排序方式: 共有692条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
This study examined the feasibility of using outpatient consultation letters as a means of assessing the clinical performance of clerks and house staff in a large teaching hospital. A total of 222 assessments were obtained based on samples of consultation problems from two clinical services. The method involved a two-stage rating scale based on the performance areas of Data Base, Problem Formulation, Diagnostic Tests, Management and Overall Assessment. The technique was investigated in terms of the objectivity, reliability, validity and efficiency of the performance ratings. Product-moment coefficients were used to assess inter- and intrarater agreement in scoring the consultation letters. These analyses identified a consistent difficulty in assessing the category of Data Base. For the remaining performance categories, interrater coefficients in the range .19-.76 and intrarater coefficients in the range .23-.96 were obtained. Other preliminary findings indicated good potential for a reliable and valid assessment. The method is technically feasible, and is based on a novel and reasonably unobtrusive approach to assessing trainee performance in a clinical setting. 相似文献
4.
L McCain 《Plastic surgical nursing》1992,12(1):28-30
The Food and Drug Administration's (FDA's) investigation into the safety of silicone gel-filled breast implants has dominated newspaper, television, and magazine headlines across the country in recent months. ASPRSN member Lynne McCain along with several patients and physicians from the Atlanta, GA area recently had an opportunity to educate lawmakers and staff on the issue of breast implants while on Capitol Hill in October. They later returned to testify before an FDA panel investigating the issue and played a key role in the panel's November decision to recommend keeping the implants on the market until further research was available on the safety of the implants. The following article details the group's efforts with lawmakers in October and before FDA panel members in November, and demonstrates that nurses and patients can make a difference! 相似文献
5.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
6.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
7.
Fumino Iwata Ernest M. Kuehl George F. Reed Lessie M. McCain William A. Gahl Muriel I. Kaiser-Kupfer 《Molecular genetics and metabolism》1998,64(4):237-242
In nephropathic cystinosis, corneal cystine crystals cause severe photophobia and corneal erosions. Topical cysteamine dissolves these crystals, but cannot be marketed because it rapidly oxidizes to the disulfide form, cystamine, at room temperature. Since cystamine itself could be used commercially, we compared the efficacy of cystamine and cysteamine with respect to cystine crystal dissolution in a randomized, double-masked clinical trial. One eye each of 14 patients with cystinosis was randomized to either cystamine or cysteamine, 0.5%, with 0.01% benzalkonium chloride; the companion eye was treated with the alternate preparation. Corneal crystals were photographed and a density score was assigned to each slide based on 13 standard slides. After 8–20 months, 6 patients showed significant reduction of the corneal crystal score in only one eye. In each case, the improved eye was the cysteamine-treated eye. Theoretically, cysteamine should dissolve both intracellular and extracellular crystals, whereas cystamine should dissolve only intracellular crystals because it must first be reduced to the free thiol by the cytoplasmic-reducing environment. Hence, the lack of efficacy of the disulfide cystamine suggests that some corneal cystine crystals in cystinosis patients are extracellular, and that another form of stable, topical cysteamine must be developed for cystinosis patients. 相似文献
8.
A DNA wih a sedimentation coefficient of 7 S (ρcs2so4: = 1.423) was isolated from DNase- and RNase-treated purified virions of each of three different oncogenic RNA viruses: murine sarcoma virus, Rauscher murine leukemia virus, and avian myeloblastosis virus. The naturally occurring DNA of murine sarcoma virus constituted about 2.5% of the total viral nucleic acid and resolved into two components (ρ = 1.698 and ρ = 1.678) when centrifuged to equilibrium in a CsCl density gradient. The viral DNA was complementary to the 18 S viral RNA subunit, but not to the 37 S or 4 S subunits. 相似文献
9.
Ari Whiteman Alice Wang Kelly McCain Betsy Gunnels Robin Toblin James Tseryuan Lee Carolyn Bridges Laura Reynolds Bhavini Patel Murthy Judy Qualters James A. Singleton Kimberley Fox Shannon Stokley LaTreace Harris Lynn Gibbs-Scharf Neetu Abad Kathryn A. Brookmeyer Susan Farrall Cassandra Pingali Anita Patel Ruth Link-Gelles Sharoda Dasgupta Radhika Gharpure Matthew D. Ritchey Kamil. E. Barbour 《MMWR. Morbidity and mortality weekly report》2021,70(19):725
10.
The findings of the study did support the faculty's hypotheses. First, only 50% of the hospitals retain responsibility for the statistical function. This finding was, however, affected by the size of the hospital, with 100% of the hospitals of 400 beds or less retaining such responsibility. Second, the findings showed that only 12.5% of the hospitals had entirely manual statistical systems. However, 50% of the hospitals did compile some statistics manually, including the daily hospital census and discharge service statistics. Finally, in looking at the UT Memphis statistics curriculum and those of 14 other medical record administration programs in the Southeast, the hypothesis that curricula did not mirror this changing practice was confirmed. Although 100% of the programs surveyed had students memorize statistical formulas, only 36% had students working with computers in the statistics course. Of the 14 programs, only 6 specifically covered QA of statistical data in the statistics course, and 9 did not deal at all with how to assess the adequacy of policies and procedures for gathering statistical information. As a result of these findings, UT Memphis has modified its statistical course to increase the emphasis on computerization, QA, and assessment of statistical policies and procedures. These changes will better prepare the UT Memphis graduate for the statistical responsibilities that they will face in the workplace. 相似文献