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121.
Nashat S. Moawad MD Heidi Gibbons MS James Liu MD Noam Lazebnik MD 《Journal of ultrasound in medicine》2009,28(10):1281-1288
Objective. The purpose of this study was to compare 3‐dimensional (3D) and 2‐dimensional (2D) ovarian follicle counts and 3D counts using stored volumes between experienced and inexperienced operators. Methods. Follicles larger than 5 mm were counted on 1 randomly selected ovary. Two‐dimensional follicle counts were compared with stored 3D volumes by the same experienced operator (registered diagnostic medical sonographer [RDMS]). Counts using 3D stored data were compared between the experienced operator and inexperienced operator (principal investigator [PI]). The mean difference in follicle counts was computed, and a 1‐sample Student t test was performed to test the hypothesis that the mean of the differences was 0. Comparison of the 2 methods and observers by Bland‐Altman plots was used to determine any systematic differences based on the total number of follicles per selected ovary. Results. Mean differences differed from 0 (P < .005) for all 3 comparisons: 2D RDMS versus 3D RDMS, 2D RDMS versus 3D PI, and 3D RDMS versus 3D PI. For the comparison of 2D versus 3D counts done by the RDMS, 5 ovaries (10%) had a difference of more than 5 follicles counted; for the 2D RDMS versus 3D PI, 11 ovaries (22%) had a difference of more than 5 follicles; for the 3D RDMS versus 3D PI, 8 ovaries (16%) had a difference of more than 5 follicles. Mean differences in counts ranged 0.29 to 1.04 for ovaries with 10 or fewer follicles compared with 3.94 to 9.00 for ovaries with more than 10 follicles. Conclusions. Follicle counts using 3D volumes were similar to 2D counts, and 3D follicle counts done by an inexperienced operator were similar to counts done by an experienced sonographer. 相似文献
122.
In this article, we introduce the special issue entitled Innovation and Integrity in Intervention Science. Its focus is on essential problems and prospects for intervention research examining two related topics, i.e., methodological issues and research integrity, and challenges in the transfer of research knowledge into practice and policy. The main aims are to identify how to advance methodology in order to improve research quality, examine scientific integrity in the field of intervention science, and discuss future steps to enhance the transfer of knowledge about evidence-based intervention principles into sustained practice, routine activities, and policy decisions. Themes of the special issue are twofold. The first includes questions about research methodology in intervention science, both in terms of research design and methods, as well as data analyses and the reporting of findings. Second, the issue tackles questions surrounding the types of knowledge translation frameworks that might be beneficial to mobilize the transfer of research-based knowledge into practice and public policies. The issue argues that innovations in methodology and thoughtful approaches to knowledge translation can enable transparency, quality, and sustainability of intervention research. 相似文献
123.
B Shohat H Joshua 《International journal of cancer. Journal international du cancer》1971,8(3):487-496
Intraperitoneal administration of Withaferin A 24 h after inoculation of Ehrlich ascites carcinoma resulted in an immediate inhibition of tumor growth, followed by complete disappearance of the malignant cells after 3-4 days. During this period a striking proliferation of macrophages in the peritoneal cavity and clustering of viable acid-phosphatase-rich macrophages around Ehrlich ascites tumor cells was observed. In addition, giant cell formation in the peritoneal cavity of the tumor-rejecting mice was commonly seen. No significant difference was found in the number of lymphocytes and polymorphonuclears of the peritoneal exudate of the tumor-rejecting mice as compared to untreated tumor-bearing mice. A similar sequence of changes with an even more striking proliferation of macrophages terminating again in complete tumor regression was observed after reinoculation of Ehrlich ascites cells to Withaferin A cured mice. Growth of Ehrlich ascites tumor cells in normal mice was prevented by passive transfer of serum or peritoneal cells, but not by spleen cells taken from immune mice. Humoral antibodies in the serum of immune mice were demonstrated by the complement fixation, the passive cutaneous anaphylaxis, and the cytotoxic tests. One-day-old suckling litters born to immune mothers were also refractory to Ehrlich ascites implantation. However, Ehrlich ascites cell growth was not affected if the litters were injected previously with a cell-free tumor homogenate. 相似文献
124.
Bensafi M Porter J Pouliot S Mainland J Johnson B Zelano C Young N Bremner E Aframian D Khan R Sobel N 《Nature neuroscience》2003,6(11):1142-1144
Neural representations created in the absence of external sensory stimuli are referred to as imagery, and such representations may be augmented by reenactment of sensorimotor processes. We measured nasal airflow in human subjects while they imagined sights, sounds and smells, and only during olfactory imagery did subjects spontaneously enact the motor component of olfaction--that is, they sniffed. Moreover, as in perception, imagery of pleasant odors involved larger sniffs than imagery of unpleasant odors, suggesting that the act of sniffing has a functional role in creating of olfactory percepts. 相似文献
125.
Surgery for rectal cancer in complex and entails many challenges. While the laparoscopic approach in general and specific to colon cancer has been long proven to have short term benefits and to be oncologically safe, it is still a debatable topic for rectal cancer. The attempt to benefit rectal cancer patients with the known advantages of the laparoscopic approach while not compromising their oncologic outcome has led to the conduction of many studies during the past decade. Herein we describe our technique for laparoscopic proctectomy and assess the current literature dealing with short term outcomes, immediate oncologic measures (such as lymph node yield and specimen quality) and long term oncologic outcomes of laparoscopic rectal cancer surgery. We also briefly evaluate the evolving issues of robotic assisted rectal cancer surgery and the current innovations and trends in the minimally invasive approach to rectal cancer surgery. 相似文献
126.
Multiple parameters of immune function were measured serially before and one and five weeks following operation in 14 patients with fibrocystic disease of the breast (Group A) and in 20 patients with stage 1-2 infiltrating duct carcinoma (Group B). These parameters included the following: WBC, total number and percentage of lymphocytes, numbers of B cells, T cells, T-active, T-helper and T-suppressor cells and the ratio between the latter as well as spontaneous suppressor or helper activity and the graft-versus-host reaction. Prior to operation no statistically significant difference was found between the two groups except for the number of T-helper cells, which was higher in Group B (p less than 0.05), and the spontaneous suppressor activity, which was higher in Group B (p less than 0.05). The finding of such a high percentage (80%) of negative graft-versus-host reactions five weeks after operation together with the high suppressor activity may indicate the presence of tumor micrometastases. The burden of surgery and general anesthesia was stronger in Group B, with a pronounced difference found between the groups (p = 0.0005), but the interaction between the influence of time (surgery and anesthesia) and the groups was not as great (p = 0.4864) and was found to be different for each group. 相似文献
127.
W R Beardslee S Powers S T Hauser J Houlihan A M Jacobson G G Noam E Macias J Hopfenbeck 《Journal of the American Academy of Child and Adolescent Psychiatry》1990,29(3):429-439
This study reports the development of adaptive processes in two groups of adolescents assessed initially and 2 years later with clinical research interviews. Students from a public high school (N = 44) and inpatients on an adolescent psychiatric ward (N = 51) formed the two subject groups. The psychiatrically hospitalized group had significantly improved scores after a 2-year interval on four of six adaptive process Summary Scales: Task Orientation, Relatedness, Self Knowledge, and Inner Synthetic Functions. However, these higher scores did not reach the levels of the high school group at either point of assessment. The scores in the high school group remained stable over time except for an increase in the area of Self Knowledge. The value of this interview-derived assessment, in comparison to other forms of measurement, is discussed, and consideration is given to factors which contribute to the differences between groups. 相似文献
128.
Tsukasa Nagaoka Fuqiang Zhao Ping Wang Noam Harel Richard P Kennan Seiji Ogawa Seong-Gi Kim 《Journal of cerebral blood flow and metabolism》2006,26(8):1043-1051
The magnitude of the blood oxygenation level-dependent (BOLD) signal depends on cerebral blood flow (CBF), cerebral blood volume (CBV) and cerebral metabolic rate of oxygen (CMRO2). Thus, it is difficult to separate CMRO2 changes from CBF and CBV changes. To detect the BOLD signal changes induced only by CMRO2 responses without significant evoked CBF and CBV changes, BOLD and CBV functional magnetic resonance imaging (fMRI) responses to visual stimulation were measured under normal and hypotension conditions in isoflurane-anesthetized cats at 4.7 T. When the mean arterial blood pressure (MABP) decreased from 89+/-10 to 50+/-1 mm Hg (mean+/-standard deviation, n=5) by infusion of vasodilator sodium nitroprusside, baseline CBV in the visual cortex increased by 28.4%+/-8.3%. The neural activity-evoked CBV increase in the visual cortex was 10.8%+/-3.9% at normal MABP, but was negligible at hypotension. Positive BOLD changes of +1.8%+/-0.5% (gradient echo time=25 ms) at normal MABP condition became prolonged negative changes of -1.2%+/-0.3% at hypotension. The negative BOLD response at hypotension starts approximately 1 sec earlier than positive BOLD response, but similar to CBV change at normal MABP condition. Our finding shows that the negative BOLD signals in an absence of CBV changes are indicative of an increase in CMRO2. The vasodilator-induced hypotension model simplifies the physiological source of the BOLD fMRI signals, providing an insight into spatial and temporal CMRO2 changes. 相似文献
129.
Jamie Ward Noam Sagiv 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(10):1261
Number forms, conscious visuo-spatial representations of the sequence of numbers, are found in around 12% of the population. However, their contribution to numerical cognition is not well understood. In this study we contrast the speeded performance of individuals with number forms versus controls on single digit multiplication, subtraction and addition. Previous research has suggested that multiplication may rely more on retrieval of verbal facts whereas subtraction relies more on online calculation using a putatively spatial ‘mental number line’. If people with number forms rely more heavily on visual-spatial strategies than verbal ones then we hypothesised that multiplication may be disproportionately affected by this strategy relative to subtraction, and this was found. 相似文献
130.
Basel-Vanagaite L Taub E Halpern GJ Drasinover V Magal N Davidov B Zlotogora J Shohat M 《European journal of human genetics : EJHG》2007,15(2):250-253
Nonsyndromic mental retardation (NSMR) is the diagnosis of exclusion in mentally retarded individuals without additional abnormalities. We have recently identified a protein-truncating mutation, G408fsX437, in the gene CC2D1A on chromosome 19p13.12 in nine consanguineous Israeli Arab families with severe autosomal recessive NSMR, and have developed a comprehensive prevention program among the at-risk population in the village. The subjects tested were healthy women who were invited to undergo the genetic screening test as a part of their routine pregnancy monitoring. One hundred and seventeen subjects reported a family history positive for mental retardation. We tested 524 pregnant or preconceptional women and found 47 carriers (approximately 1/11), whose spouses were then recommended to undergo testing. We identified eight carrier couples, who were given genetic counseling and offered prenatal diagnosis. Of all the marriages, 28.6% were consanguineous; 16.5% of the total were between first cousins. The high prevalence of the mutation can be explained both by the founder effect owing to the generally high consanguinity rate among the inhabitants of the village, and also because two families with excessive numbers of mentally retarded offspring were unacceptable as marriage partners by the rest of the families. This is the first example of the establishment of a large-scale genetic screening program for autosomal recessive NSMR, which was made possible owing to the high frequency of the specific causative mutation in this isolated population. 相似文献