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111.
The ventral arc of the pubis is frequently used for sexing adult human hip bones. This study addresses the issues of the anatomical and developmental bases for the ventral arc. Dissection of seven adult pelves (four females and three males) demonstrates that the sexes are identical in the muscular and ligamentous attachments to this ridge of bone. The tendons of gracilis and adductor brevis, which are fused for a variable extent, arise from the ridge of bone, and the fibers of the ventral pubic ligament attach to its medial border. Lateral placement of the ventral arc is defined in terms of the minimum distance between the ridge of bone and the inferior border of the symphyseal face of the pubis. The hypothesis that lateral placement of the ventral arc is positively correlated with pubic length was tested using two random samples of adult female hip bones (N = 50 for both whites and blacks) from the Hamann-Todd collection. The correlation between these variables is significant. The results support the argument that lateral placement of the ventral arc is related to the amount of postadolescent growth occurring at the symphyseal border of the pubis. Therefore, the ventral arc should not be considered as an independent criterion from pubic length in sexing adult hip bones.  相似文献   
112.
Two adjacent catchments in the Otway Ranges of Victoria, Australia (Redwater and Clearwater) produce water with markedly different concentrations of dissolved organic carbon (DOC) during summer. Water from Redwater Creek had a DOC concentration of 32 mg L–1, while water from Clearwater Creek had a DOC concentration of 3.8 mg L–1. Examination of the catchments revealed that while climate, topography, vegetation and land use were similar, the soils were different. The objective of this study was to examine the relationship between the concentration and chemical composition of DOC in stream waters and the nature of soils in the two catchments. Soil mapping determined that clayey soils formed on Cretaceous sediments (Cretaceous soils) occurred throughout both catchments, but that Redwater Catchment also contained a large area (39%) of sandy soils formed on Tertiary sediments (Tertiary soils). The concentration of DOC in forest floor leachate was high in both the Tertiary and Cretaceous areas; however, the concentration of DOC in water draining areas dominated by Tertiary soils was greater than that in water draining areas dominated by Cretaceous soils. Laboratory experiments showed that the Cretaceous soils had higher adsorption capacities for forest floor leachate DOC than the Tertiary soils. The difference in DOC concentrations of the streams was therefore attributed to the difference in adsorption capacity of catchment soils for DOC. Adsorption capacities of the soils were found to be a function of their clay contents and specific surface areas.Solid-state3C nuclear magnetic resonance spectroscopy and pyrolysis-mass spectrometry were used to determine the chemical structure of DOC found in streams and forest floor leachate samples and that remaining in solution after interaction with soil. Chemistry of DOC in forest floor leachate was similar before and after interaction with soil, indicating no preferential adsorption of a particular type of carbon. Thus, differences between the chemical structure of stream DOC and forest floor leachate DOC could be attributed to microbial modifications during its movement through soils and into the streams, rather than losses by adsorption.  相似文献   
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The formation of organic sulfur from inorganic sulfate was investigated in hardwood forest floor and mineral horizons. All samples converted sulfate-sulfur into a non-salt extractable form which was recoverable only under conditions which release organic matter. This conversion was inhibited by azide, and depending upon the horizon, by erythromycin, candicidin, chloramphenicol and tetracycline. The form of sulfur generated in the 02 forest floor layer and in Al-horizon soil was characterized after isolation by pyrophosphate extraction at pH 8. The organosulfur extracts exhibited an average C:N:S ratio of 103:6:1. The ester sulfate content of the 02 extract was 61% by hydriodic acid (HI) reduction and 62% by hydrolysis in 3N HCl at 121 °C. However, compared to hydrolysis, reduction yielded lower estimates of ester sulfate for two of the three soil extracts analyzed. In view of the electrophoretic heterogeneity of all extracts, it is suggested that some may contain stable ester linkages that hydrolyze only after prolonged treatment and that the standard procedure for HI-reduction may provide conditions of temperature and contact time with the acid which are insufficient for the release of sulfate from these esters.Author to whom reprint requests should be addressed  相似文献   
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Biogeochemistry of lead in an urban forest in Athens,Greece   总被引:1,自引:0,他引:1  
The distribution and cycling of lead (Pb) was examined in an urban forest of Aleppo pine stand in Athens. Concentrations of the soluble fraction of Pb in bulk and throughfall deposition were low, reflectingthe change in petrol form in recent years. However, Pb concentrations in forest floor remain high due to Pb accumulation in previous years. The soil A horizon showed unexpectedly high levels of Pb concentration resulted probably from Pb migration from organic horizons. Pb concentrations in pine needles, litterfall and wood were low, whereas tree bark acted as a sink for Pb and stored high amounts of the metal.  相似文献   
116.
Floor space allowance for pigs has substantial effects on pig growth and welfare. Data from 30 papers examining the influence of floor space allowance on the growth of finishing pigs was used in a meta-analysis to develop alternative prediction equations for average daily gain (ADG), average daily feed intake (ADFI) and gain : feed ratio (G : F). Treatment means were compiled in a database that contained 30 papers for ADG and 28 papers for ADFI and G : F. The predictor variables evaluated were floor space (m2/pig), k (floor space/final BW0.67), Initial BW, Final BW, feed space (pigs per feeder hole), water space (pigs per waterer), group size (pigs per pen), gender, floor type and study length (d). Multivariable general linear mixed model regression equations were used. Floor space treatments within each experiment were the observational and experimental unit. The optimum equations to predict ADG, ADFI and G : F were: ADG, g=337.57+(16 468×k)−(237 350×k2)−(3.1209×initial BW (kg))+(2.569×final BW (kg))+(71.6918×k×initial BW (kg)); ADFI, g=833.41+(24 785×k)−(388 998×k2)−(3.0027×initial BW (kg))+(11.246×final BW (kg))+(187.61×k×initial BW (kg)); G : F=predicted ADG/predicted ADFI. Overall, the meta-analysis indicates that BW is an important predictor of ADG and ADFI even after computing the constant coefficient k, which utilizes final BW in its calculation. This suggests including initial and final BW improves the prediction over using k as a predictor alone. In addition, the analysis also indicated that G : F of finishing pigs is influenced by floor space allowance, whereas individual studies have concluded variable results.  相似文献   
117.
Dienogest (DNG) administration is a well-established treatment for endometriosis but bleeding irregularities remain its main disadvantage. Changes in diet, mainly to vegetable consumption, are beneficial in the treatment of estrogen-related pathologies but their use for endometriosis has been poorly studied. In this study, addition of the phytochemical 3,3′-diindolylmethane (DIM) to DNG therapy has been investigated in in vitro and ex vivo models for endometriosis and in a small cohort of women with endometriosis. Endometrial Ishikawa cells were treated with DNG or DIM at dosages from 10?10?M to 10?5?M for up to 72?h. Cell proliferation was measured by assessing BrdU incorporation. Endometrial tissue from women with endometriosis and controls was incubated with DNG or a combination of DNG and DIM. Tissue viability was determined using a modified colorimetric MTS assay. 17β-estradiol secretion was quantified by an electro-chemiluminescence immunoassay. Finally, DNG as monotherapy or in combination with DIM was randomly administered to women with endometriosis (n?=?8) over 3 months. Bleeding patterns and associated pelvic pain were assessed by Visual Analogue Scale (VAS). DNG and DIM significantly reduced cell proliferation in Ishikawa cells. Ex vivo, DIM reduced viability and estradiol secretion specifically in endometriotic but not in normal endometrial tissue. This effect was enhanced by combination with DNG. Endometriosis associated pelvic pain was significantly reduced in patients taking the DNG-DIM combination therapy compared to those taking DNG alone. Bleeding pattern (number and duration of episodes) was significantly improved by addition of DIM to the DNG treatment. In conclusion, addition of DIM enhances effects of DNG ex vivo and may ameliorate bleeding patterns in endometriosis patients.  相似文献   
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目的:分析因症状性盆腔器官脱垂(POP)接受手术治疗患者的临床资料,探讨不同手术方式的疗效及临床应用。方法:选择2010年7月至2014年12月在青岛大学附属医院因POP接受手术治疗的176例患者为研究对象,其中全盆底重建术97例,阴道骶骨固定术22例,传统手术(经阴子宫切除+阴道壁修补术)57例。回顾性分析不同术式患者的临床资料、手术疗效及病人生活质量评分及性生活影响等相关资料。结果:1三组手术患者在手术时间、出血量及住院费用上均存在不同的差别。其中盆底重建组手术时间及出血量明显低于传统手术组及骶骨固定组(P=0.00)。2176例患者中有163例患者完成术后12个月随访。其中传统手术组患者的客观治愈率低于其他两组患者,差异有统计学意义(P0.05)。3三种术式术后6、12个月PFDI-20评分均较术前下降,且差异有统计学意义(P0.05),三组间术前及术后6个月PFDI-20评分比较无差异;术后12个月传统手术组评分高于其他两组,差异有统计学意义(P0.05)。4在术后恢复性生活的患者当中,盆底重建组及传统组中有患者出现不同程度的性交痛,而骶骨固定组其性生活较前术前明显改善,三组间差异有统计学意义(P0.05)。三组患者术后新发尿失禁的比率无统计学意义。结论:三种术式各具优缺点,但均为症状性POP的有效治疗方式。在临床应用中,要综合评估患者的年龄、合并症、性生活要求及经济情况等,制定和选择最合理的个体化方案。  相似文献   
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