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91.
92.
Weiss E Wetterstrom W Nadel D Bar-Yosef O 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(26):9551-9555
The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73-100] "broad spectrum revolution" (BSR) hypothesis, which posits that the transition to farming in southwest Asia entailed a period during which foragers broadened their resource base to encompass a wide array of foods that were previously ignored in an attempt to overcome food shortages. Although these resources undoubtedly included plants, nearly all BSR hypothesis-inspired research has focused on animals because of a dearth of Upper Paleolithic archaeobotanical assemblages. Now, however, a collection of >90,000 plant remains, recently recovered from the Stone Age site Ohalo II (23,000 B.P.), Israel, offers insights into the plant foods of the late Upper Paleolithic. The staple foods of this assemblage were wild grasses, pushing back the dietary shift to grains some 10,000 years earlier than previously recognized. Besides the cereals (wild wheat and barley), small-grained grasses made up a large component of the assemblage, indicating that the BSR in the Levant was even broader than originally conceived, encompassing what would have been low-ranked plant foods. Over the next 15,000 years small-grained grasses were gradually replaced by the cereals and ultimately disappeared from the Levantine diet. 相似文献
93.
94.
OBJECTIVES/HYPOTHESIS: The objective was to extend our knowledge of the effect of birth control pills on voice quality in women based on various acoustic measures. STUDY DESIGN: A longitudinal comparative study of 14 healthy young women over a 36- to 45-day period. METHODS: Voices of seven women who used birth control pills and seven women who did not were recorded repeatedly approximately 20 times. Voice samples were analyzed acoustically, using an extended set of frequency perturbation parameters (jitter, relative average perturbation, pitch period perturbation quotient), amplitude perturbation parameters (shimmer, amplitude average perturbation quotient), and noise indices (noise-to-harmonics ratio, voice turbulence index). RESULTS: Voice quality and stability were found to be better among the women who used birth control pills. Lower values were found for all acoustic measures with the exception of voice turbulence index. Results also provided preliminary indication for vocal changes associated with the days preceding ovulation. CONCLUSION: In contrast to the traditional view of oral contraceptives as a risk factor for voice quality, and in keeping with the authors' previous work, the data in the present study showed that not only did oral contraceptives have no adverse effect on voice quality but, in effect, most acoustic measures showed improved voice quality among women who used the birth control pill. The differences in the noise indices between groups may also shed light on the nature of the effect of sex hormones on vocal fold activity. It was suggested that hormonal fluctuations may have more of an effect on vocal fold regulation of vibration than on glottal adduction. 相似文献
95.
Amir O Biron-Shental T 《Current opinion in otolaryngology & head and neck surgery》2004,12(3):180-184
PURPOSE OF REVIEW: Sex hormone fluctuations were shown to affect female vocal folds and laryngeal function. Laryngeal changes are evident throughout the span of life, starting at puberty with the arousal of the hormonal system, fluctuating systematically during the reproductive years with the menstrual cycle, and then changing again with the decline of hormonal activity at menopause. This paper reviews recent developments in this field. RECENT FINDINGS: Early studies that explored this relation were based merely on subjective impressions of voice quality, recent studies have used more objective tools for examining this relation, including histologic observations, stroboscope, electroglottography (EGG), and computerized acoustic analyses. In these studies, the larynx was shown to be a hormonal target organ and, as such, sex hormones affect its morphology, histology, and function, similar to their effect on the genitals and other organs. SUMMARY: Examining the relation between sex hormones and the larynx could assist in understanding the mechanisms of voice production, and it could provide the clinician with supplemental diagnostic information on different medical conditions. 相似文献
96.
BACKGROUND: The incidence of ovarian metastasis in women with clinical stage I endometrial carcinoma is generally reported to be 5%, leading to the practice of removing the ovaries at surgery even in young patients. METHODS: A retrospective study of 84 patients with clinical stage I endometrial cancer was carried out. Patients were excluded if the pathologic study revealed any evidence of extrauterine, apart from adnexal, spread or if the peritoneal cytology was positive. Patients with serous papillary or clear cell tumor histology were also excluded. RESULTS: Sixty-seven patients fulfilled the inclusion criteria. Only three (4%) patients were found to be in surgical stage IIIA, all three had grade 3 tumors. Of these patients, two had uterine serosal involvement and one had a microscopic tumor implant in a fallopian tube; none had ovarian metastasis. CONCLUSIONS: The risk of ovarian metastasis in women with well to moderately differentiated endometrial cancer, myometrial invasion limited to less than one half of the myometrium, negative peritoneal cytology and no evidence of metastatic lymph node spread is negligible. Young patients with a preoperative histological diagnosis of well to moderately differentiated endometrial carcinoma may be surgically staged, leaving the final decision regarding removal of the ovaries pending a thorough pathological review of the surgical specimens. 相似文献
97.
To determine the extent to which electrophysiologic tests of the afferent visual pathway are affected by vitrectomy, the procedure was performed in 15 eyes of 11 adult Dutch-belted rabbits. An electroretinogram (ERG), visually evoked cortical potential (VECP), and electrically evoked cortical potential (EECP) were obtained preoperatively and sequentially after surgery. For electrical stimulations, biphasic impulses were delivered to the retina. Post-vitrectomy declines of 49, 25, and 41% from the median baseline amplitudes and increases of 13, 18, and 17% from the median baseline latency values were found for ERG, VECP, and EECP, respectively. At 90 min, 13 to 30% of eyes still had an amplitude more than 10% below baseline on at least one of the three tests, whereas 10 to 47% of eyes had an abnormal latency more than 10% above baseline on at least one of the three tests. Amplitudes were more likely than latencies to return to near baseline, but for eyes that remained subnormal, the decline was greater for amplitudes than latencies. Significant alterations in retinal function, manifested by declines in amplitudes and increases in latencies of the ERG, VECP, and EECP, persist in a large proportion of eyes up to 90 min post-vitrectomy. 相似文献
98.
BACKGROUND: Apoptosis (i.e., programmed cell death) plays a major role in the development of astrocytic tumors, which are the most common tumors of the central nervous system. ARTS, a proapoptotic protein that is localized in the mitochondria, promotes apoptosis by functioning as an XIAP antagonist and a caspase activator. METHODS: To investigate the role of ARTS in astrocytoma, the authors examined protein expression and apoptotic activity in 72 astrocytic tumors, which included low-grade astrocytomas, anaplastic astrocytomas, and glioblastomas. RESULTS: Whereas normal astrocytes did not express the ARTS protein, astrocytoma cells strongly expressed ARTS, and the expression of this protein increased with increasing tumor grade. Furthermore, increased levels of ARTS were significantly associated with higher rates of apoptosis (as measured using the terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick end-labeling [TUNEL] assay as well as an immunohistochemical staining assay for active caspase-3) in these tumors. Levels of two other apoptosis-related proteins, p53 and Bcl-2, also were examined using immunohistochemical methods; ARTS expression was found to be positively correlated with expression of the former and negatively correlated with expression of the latter, which is known to possess antiapoptotic activity. CONCLUSIONS: The results of the current study suggest that ARTS levels reliably reflect the ability of cells to undergo apoptosis, which serves as a defense mechanism against the development and progression of astrocytoma. Furthermore, ARTS expression, when taken into consideration in combination with tumor grade, was the only independent predictor of survival identified in the current analysis. Thus, the authors conclude that ARTS may possess utility as a prognostic marker, as well as a therapeutic tool, for patients with astrocytoma. 相似文献
99.
Melamed O Gerstner W Maass W Tsodyks M Markram H 《Trends in neurosciences》2004,27(1):11-4; discussion 14-5
100.
Tokar M Yerushalmi R Bobilev D Levi I Geffen D Shpilberg O 《Leukemia & lymphoma》2004,45(9):1853-1856
Chemotherapy and radiotherapy have been the principal modalities of treatment for diffuse large B-cell non-Hodgkin's lymphoma (B-NHL) for over 30 years. Various treatment regimens have been designed over the years to try to increase response and cure rates. The role of surgery has been generally restricted to defined and limited situations including diagnostic tissue biopsies and treating abdominal emergencies such as organ rupture or perforation. We present two cases of refractory B-NHL, where surgery was used as a part of stepwise and multi-modal treatment with curative intent. In both cases, the treatment approach included standard dose chemotherapy, eradication of residual mass by surgery, high dose chemotherapy (HDC) with stem cell support and posttransplantant immunotherapy. Currently, 2 years after completing the therapy, both patients are well with no evidence of active disease. Based on our experience with 2 patients we believe that in specific cases of residual chemo-resistant lymphomatous mass, surgery should be considered as a part of a multimodal approach. 相似文献