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711.
Gholamhosein Hasanshahi Jaber Karimi Fatemeh Jahan Habib Abbasipour Alireza Askarianzade Ali Hossein Rahimi 《Archives Of Phytopathology And Plant Protection》2013,46(6):681-689
The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), has worldwide distribution and found wherever cruciferous plants is grown. In this study, fluctuations of parasitism rate of P. xylostella by Oomyzus sokolowskii on different cauliflower cultivars were evaluated in the field during 2011 at research station of the Shahed University (South of Tehran). This investigation was conducted on the eight cauliflower cultivars including Smilla, Snow mystique, White cloud, Buris, Galiblanka, Snow crown, SG and Tokita in a randomised complete block design with five replications. The results showed that density of total larva and pupa of the diamondback moth on Buris and Snow crown cultivars is lower than other cultivars. The highest and the lowest percentage of parasitism by O. sokolowskii was observed on Buris cultivar (7.93?±?0.91%) and SG cultivar (1.28?±?0.36%) during the season, respectively. 相似文献
712.
Mohammad Reza Ay Abolfazl Mehranian Asghar Maleki Hossien Ghadiri Pardis Ghafarian Habib Zaidi 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2013,29(3):249-260
Beam hardening filters have long been employed in X-ray Computed Tomography (CT) to preferentially absorb soft and low-energy X-rays having no or little contribution to image formation, thus allowing the reduction of patient dose and beam hardening artefacts. In this work, we studied the influence of additional copper (Cu) and aluminium (Al) flat filters on patient dose and image quality and seek an optimum filter thickness for the GE LightSpeed VCT 64-slice CT scanner using experimental phantom measurements. Different thicknesses of Cu and Al filters (0.5–1.6 mm Cu, 0.5–4 mm Al) were installed on the scanner’s collimator. A planar phantom consisting of 13 slabs of Cu having different thicknesses was designed and scanned to assess the impact of beam filtration on contrast in the intensity domain (CT detector’s output). To assess image contrast and image noise, a cylindrical phantom consisting of a polyethylene cylinder having 16 holes filled with different concentrations of K2HPO4 solution mimicking different tissue types was used. The GE performance and the standard head CT dose index (CTDI) phantoms were also used to assess image resolution characterized by the modulation transfer function (MTF) and patient dose defined by the weighted CTDI. A 100 mm pencil ionization chamber was used for CTDI measurement. Finally, an optimum filter thickness was determined from an objective figure of merit (FOM) metric. The results show that the contrast is somewhat compromised with filter thickness in both the planar and cylindrical phantoms. The contrast of the K2HPO4 solutions in the cylindrical phantom was degraded by up to 10% for a 0.68 mm Cu filter and 6% for a 4.14 mm Al filter. It was shown that additional filters increase image noise which impaired the detectability of low density K2HPO4 solutions. It was found that with a 0.48 mm Cu filter the 50% MTF value is shifted by about 0.77 lp/cm compared to the case where the filter is not used. An added Cu filter with approximately 0.5 mm thickness accounts for 50% reduction in radiation-absorbed dose as measured by the weighted CTDI. The FOM results indicate that with an additional filter of 0.5 mm Cu or minimum 4 mm Al, a good compromise between image quality and patient dose is achieved for CT images acquired at tube voltages of 120 and 140 kVp. The results seem to indicate that an optimum filter for high kVp acquisitions, routinely used in cardiovascular imaging, should be 0.5 mm copper or 4 mm aluminium minimum. 相似文献
713.
Feridoun Karimi-Busheri Victoria Zadorozhny Ewa Carrier Habib Fakhrai 《Cell and tissue banking》2013,14(2):175-186
Cryopreservation is a common procedure widely used in biological and clinical sciences. Similar protocols are also applied in preserving cancer stem cells, a field with high promises and challenges. Specific cell surface membrane proteins are considered to be biomarkers of cancer stem cells and they may play a critical role in differentiating stem cells from non stem cells. We have looked at the possible effect of long-term cryopreservation on the molecular integrity of breast MCF7 and lung, A549 and H460, cancer stem cells and to assess if these cells are more sensitive to long-term storage process. We analyzed the expression of CD24 and CD38 as two potent biomarkers of lung cancer stem cells and EpCAM and ALDH that are used as biomarkers of a wide range of cancer stem cells. We also selected three genes essential for the normal functioning of the cells, Fos, MUC1, and HLA. Our results indicate a pattern of down-regulation in the expression of the genes following freezing, in particular among cell surface marker proteins. Global gene expression of the post-thaw breast and lung cancer stem cells also reveals a significant down-regulation in freeze-thaw cells independent from each other. Analyzing the canonical pathways between two populations reveals a significant alteration in the gene expression of the pathways involved in cell cycle, mitosis, and ataxia telangiectasia mutated pathways. Overall, our results indicate that current protocols for long-term storage of lung and breast cancer stem cells may substantially influence the activity and function of genes. 相似文献
714.
Sidrah Nausheen Sajid B. Soofi Kamran Sadiq Atif Habib Ali Turab Zahid Memon M. Imran Khan Zamir Suhag Zaid Bhatti Imran Ahmed Rajiv Bahl Shireen Bhutta Zulfiqar A. Bhutta 《PloS one》2013,8(10)
Objective
To assess performance of the WHO revised verbal autopsy tool for ascertaining the causes of still birth in comparison with reference standard cause of death ascertained by standardized clinical and supportive data.Methods
All stillbirths at a tertiary hospital in Karachi, Pakistan were prospectively recruited into study from August 2006- February 2008. The reference standard cause of death was established by two senior obstetricians within 48 hours using the ICD coding system. Verbal autopsy interviews using modified WHO tool were conducted by trained health workers within 2- 6 weeks of still birth and the cause of death was assigned by second panel of obstetricians. The performance was assessed in terms of sensitivity, specificity and Kappa.Results
There were 204 still births. Of these, 80.8% of antepartum and 50.5% of intrapartum deaths were correctly diagnosed by verbal autopsy. Sensitivity of verbal autopsy was highest 68.4%, (95%CI: 46-84.6) for congenital malformation followed by obstetric complication 57.6%, (95%CI: 25-84.2). The specificity for all major causes was greater than 90%. The level of agreement was high (kappa=0.72) for anomalies and moderate (k=0.4) for all major causes of still birth, except asphyxia.Conclusion
Our results suggest that verbal autopsy has reasonable validity in identifying and discriminating between causes of stillbirth in Pakistan. On the basis of these findings, we feel it has a place in resource constrained areas to inform strategic planning and mobilization of resources to attain Millennium Development Goals. 相似文献715.
在巴基斯坦对仓鸮食性的季节变化进行了研究。通过分析连续3年在6个地区搜集的2 360个仓鸮回吐食物团,发现其食物主要是小型哺乳动物(95.6 %)。其中,家(Suncus murinus)有最高的比例,达65.6%(冬季最多78%,夏季最少27%)。就生物量而言,小型哺乳动物占仓鸮食物总生物量的99% 。 相似文献
716.
717.
Among grain legumes, faba bean is becoming increasingly popular in European agriculture due to recent economic and environmental
interests. Faba bean can be a highly productive crop, but it is sensitive to drought stress and yields can vary considerably
from season to season. Understanding the physiological basis of drought tolerance would indicate traits that can be used as
indirect selection criteria for the development of cultivars adapted to drought conditions. To assess genotypic variation
in physiological traits associated with drought tolerance in faba bean and to determine relationships among these attributes,
two pot experiments were established in a growth chamber using genetic materials that had previously been screened for drought
response in the field. Nine inbred lines of diverse genetic backgrounds were tested under adequate water supply and limited
water conditions. The genotypes showed substantial variation in shoot dry matter, water use, stomatal conductance, leaf temperature,
transpiration efficiency, carbon isotope discrimination (Δ13C), relative water content (RWC) and osmotic potential, determined at pre-flowering vegetative stage. Moisture deficits decreased
water usage and consequently shoot dry matter production. RWC, osmotic potential, stomatal conductance and Δ13C were lower, whereas leaf temperature and transpiration efficiency were higher in stressed plants, probably due to restricted
transpirational cooling induced by stomatal closure. Furthermore, differences in stomatal conductance, leaf temperature, Δ13C and transpiration efficiency characterized genotypes that were physiologically more adapted to water deficit conditions.
Correlation analysis also showed relatively strong relationships among these variables under well watered conditions. The
drought tolerant genotypes, ILB-938/2 and Melodie showed lower stomatal conductance associated with warmer leaves, whereas
higher stomatal conductance and cooler leaves were observed in sensitive lines (332/2/91/015/1 and Aurora/1). The lower value
of Δ13C coupled with higher transpiration efficiency in ILB-938/2, relative to sensitive lines (Aurora/1 and Condor/3), is indeed
a desirable characteristic for water-limited environments. Finally, the results showed that stomatal conductance, leaf temperature
and Δ13C are promising physiological indicators for drought tolerance in faba bean. These variables could be measured in pot-grown
plants at adequate water supply and may serve as indirect selection criteria to pre-screen genotypes. 相似文献
718.
Cardis E Vrijheid M Blettner M Gilbert E Hakama M Hill C Howe G Kaldor J Muirhead CR Schubauer-Berigan M Yoshimura T Bermann F Cowper G Fix J Hacker C Heinmiller B Marshall M Thierry-Chef I Utterback D Ahn YO Amoros E Ashmore P Auvinen A Bae JM Bernar J Biau A Combalot E Deboodt P Diez Sacristan A Eklöf M Engels H Engholm G Gulis G Habib RR Holan K Hyvonen H Kerekes A Kurtinaitis J Malker H Martuzzi M Mastauskas A Monnet A Moser M Pearce MS Richardson DB Rodriguez-Artalejo F Rogel A Tardy H 《Radiation research》2007,167(4):396-416
A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI <0, 20.6; 83 deaths) and ill-defined and secondary cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328 deaths). Stratification on duration of employment had a large effect on the ERR/Sv, reflecting a strong healthy worker survivor effect in these cohorts. This is the largest analytical epidemiological study of the effects of low-dose protracted exposures to ionizing radiation to date. Further studies will be important to better assess the role of tobacco and other occupational exposures in our risk estimates. 相似文献
719.
Agopian A Ronzon F Sauzéat E Sodoyer R El Habib R Buchet R Chevalier M 《Biochimica et biophysica acta》2007,1774(3):351-358
The formulation of human vaccines often includes adjuvants such as aluminum hydroxide that are added to enhance the immune responses to vaccine antigens. However, these adjuvants may also affect the conformation of antigenic proteins. Such structural modifications could lead to changes in antigenicity such that suboptimal protective immune responses could be generated relative to those induced by the vaccine antigens alone. Here, we used attenuated total reflectance infrared spectroscopy (ATR-FTIR) to compare the secondary structures of recombinant HIV-1-gp41 (gp41) in solution or adsorbed to aluminum hydroxide. The gp41 secondary structure content was 72% alpha-helices and 28% beta-sheets in 5 mM formate buffer p(2)H 2.5, while it was 66% beta-sheets and 34% random coil in acetonitril/(2)H(2)O (95/5:v/v). A fully reversible conformational change of gp41 in acetonitril/(2)H(2)O (95/5:v/v) was observed upon addition of either 35 mM formate p(2)H 2.5 or 0.1% (w/v) detergent (Tween 20, Hecameg, Brij 35 or beta-d-octyl-glucopyranoside). When gp41 was adsorbed to aluminum hydroxide in the presence of 0.1% (w/v) detergent, in either formate or in acetonitril/(2)H(2)O (95/5:v/v) its secondary structure remained stable and was identical to that of gp41 in 5 mM formate buffer p(2)H 2.5. The method described here could be applied for the characterization of gp41 conformers for use in immunological screening of antigens, and more generally to all antigenic proteins adsorbed to aluminum hydroxide. 相似文献
720.
Tamir A Basagila E Kagahzian A Jiao L Jensen S Nicholls J Tate P Stamp G Farzaneh F Harrison P Stauss H George AJ Habib N Lechler RI Lombardi G 《Cancer immunology, immunotherapy : CII》2007,56(12):2017-2016
Background Dendritic cells (DCs) are the most effective antigen-presenting cells. In the last decade, the use of DCs for immunotherapy
of cancer patients has been vastly increased. High endocytic capacity together with a unique capability of initiating primary
T-cell responses have made DCs the most potent candidates for this purpose. Although DC vaccination occasionally leads to
tumor regression, clinical efficacy, and immunogenicity of DCs in clinical trials has not been yet clarified. The present
study evaluated the safety and effectiveness of tumor-lysate loaded DC vaccines in advanced colorectal cancer (CRC) patients
with carcinoembryonic antigen (CEA) positive tumors.
Results Six patients HLA-A*0201-positive were vaccinated with autologous DCs loaded with tumor lysates (TL) together with tetanus
toxoid antigen, hepatitis B, and influenza matrix peptides. Two additional patients were injected with DCs that were generated
from their sibling or parent with one haplotype mismatch. All patients received the vaccines every 2 weeks, with a total of
three intra-nodal injections per patient. The results indicated that DC vaccination was safe and well tolerated by the patients.
Specific immune responses were detected and in some patients, transient stabilization or even reduction of CEA levels were
observed. The injection of haplotype mismatched HLA-A*0201-positive DCs resulted in some enhancement of the anti-tumor response
in vitro and led to stabilization/reduction of CEA levels in the serum, compared to the use of autologous DCs.
Conclusion Altogether, these results suggest that TL-pulsed DCs may be an effective vaccine method in CRC patients. Elimination of regulatory
mechanisms as well as adjustment of the vaccination protocol may improve the efficacy of DC vaccination.
An erratum to this article can be found at 相似文献