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991.
The protein content and allergen composition was studied of cashews from 8 different origins (Benin, Brazil, Ghana, India, Ivory Coast, Mozambique, Tanzania, Vietnam), subjected to different in‐shell heat treatments (steamed, fried, drum‐roasted). On 2D electrophoresis, 9 isoforms of Ana o 1, 29 isoforms of Ana o 2 (11 of the acidic subunit, 18 of the basic subunit), and 8 isoforms of the large subunit of Ana o 3 were tentatively identified. Based on 1D and 2D electrophoresis, no difference in allergen content (Ana o 1, 2, 3) was detected between the cashews of different origins (P > 0.5), some small but significant differences were detected in allergen solubility between differently heated cashews. No major differences in N‐ and C‐terminal microheterogeneity of Ana o 3 were detected between cashews of different origins. Between the different heat treatments, no difference was detected in glycation, pepsin digestibility, or IgE binding of the cashew proteins.  相似文献   
992.
Clenbuterol residue analysis by HPLC-HPTLC in urine and animal tissues   总被引:1,自引:0,他引:1  
A method for clenbuterol residue analysis in urine and animal tissues has been developed. The detection limits are 0.25 micrograms/l and 0.5 micrograms/kg, respectively. The recovery in urine varies from 85% to 90% and in animal tissues from 70% to 74%. The beta 2-agonist was liberated from the tissues by an enzymatic digestion, purified on Chem Elut columns using alkaline conditions and extracted with 0.01 mol/l HCl. Clenbuterol was quantified by high-performance liquid chromatography (HPLC) on a RP-8 column and a post-column reaction procedure. High-performance thin-layer chromatography (HPTLC) was performed on silica gel 60 plates and clenbuterol visualized by means of the modified Ehrlich's TLC spray reagent. Since this method is sensitive, as is HPLC, it was used to obtain a confirmation and to exclude false positive results.  相似文献   
993.
994.
Sorption of carbaryl (1-naphthyl-N-methyl-carbamate) from aqueous suspension to smectite was studied using Fourier transform infrared (FTIR), high-performance liquid chromatography (HPLC) (for batch sorption), and quantum chemical methods. The amount of carbaryl sorbed was strongly dependent on the surface-charge density of the smectite with more sorption occurring on the two "low" surface-charge density smectites (SHCa-1 and SWy-2) compared to that of the high surface-charge SAz-1 smectite. In addition, the amount of carbaryl sorbed was strongly dependent on the nature of the exchangeable cation and followed the order of Ba approximately Cs approximately Ca > Mg approximately K > Na approximately Li for SWy-2. A similartrend was found for hectorite (SHCa-1) of Cs > Ba > Ca > K approximately Mg > Na approximately Li. Using the shift of the carbonyl stretching band as an indicator of the strength of interaction between carbaryl and the exchangeable cation, the observed order was Mg > Ca > Ba approximately K > Na > Cs. The position of the carbonyl stretching band shifted to lower wavenumbers with increasing ionic potential of the exchangeable cation. Density functional theory predicted a cation-induced lengthening of the C=O bond, resulting from the carbonyl group interacting directly with the exchangeable cation in support of the spectroscopic observations. Further evidence was provided by a concomitant shift in the opposite direction by several vibrational bands in the 1355-1375 cm(-1) region assigned to stretching bands of the carbamate N-Ccarbonyl and Oether-Ccarbonyl bonds. These data indicate that carbaryl sorption is due, in part, to site-specific interactions between the carbamate functional group and exchangeable cations, as evidenced by the FTIR data. However, these data suggest that hydrophobic interactions also contribute to the overall amount of carbaryl sorbed. For example, the FTIR data indicated thatthe weakest interaction occurred when Cs+ was the exchangeable cation. In contrast, the highest amount of carbaryl sorption was observed on Cs-exchanged smectite. Of all the cations studied, Cs has the lowest enthalpy of hydration. It is suggested that this low hydration energy provides the carbaryl with greater access to the hydrophobic regions of the siloxane surface.  相似文献   
995.
This study compared physiological and productive parameters in 3/4 Holstein × 1/4 Gir dairy cows receiving a prepartum concentrate containing ammonium chloride to reduce urine pH near 7.0 (CON; n = 17), or a commercial anionic supplement to reduce urine pH near 6.0 (SUPP; n = 17). Nonlactating, multiparous, pregnant cows were assigned to receive SUPP or CON beginning 21 d before expected date of calving. Cows were maintained in a single drylot pen with ad libitum access to corn silage, and individually received their prepartum concentrate once daily (0800 h) before calving. Cows from both treatments completely consumed their concentrate allocation within 30 min after feeding. Cow body weight and body condition score were recorded once weekly, urine pH measured every 3 d, and blood samples collected on d ?21, ?14, ?9, ?6, and ?3 relative to expected calving date. After calving (d 0), cows were moved to an adjacent drylot pen with ad libitum access to water and a total mixed ration, and were milked twice daily (0600 and 1700 h). Cow body weight and body condition score were recorded once weekly and individual milk production was recorded daily until 30 d in milk (DIM). Blood samples were collected before each milking during the first 5 DIM, as well as at 6, 9, 16, 23, and 30 DIM before the morning milking. Based on actual calving dates, cows received SUPP or CON for (mean ± standard error) 19.2 ± 1.2 and 19.0 ± 0.9 d before calving, respectively. Urine pH was less in SUPP versus CON cows during the last 15 d of gestation (6.12 vs. 7.15, respectively). Milk yield during the first 5 DIM and throughout the experimental period was greater in SUPP versus CON cows (by 20 and 14%, respectively), whereas serum Ca concentrations did not differ between treatments during the first 5 DIM. Serum concentrations of fatty acids were greater in SUPP versus CON cows 3 d before and at calving (by 52 and 22%, respectively), whereas SUPP cows had lower serum glucose and cortisol concentration at calving (by 23 and 27%, respectively). Hence, the SUPP treatment decreased prepartum urine pH near 6.0 in Holstein × Gir dairy cows without depressing concentrate intake compared with CON, although total dry matter intake was not evaluated to fully investigate feed intake responses. Moreover, the SUPP treatment transiently affected serum glucose, fatty acids, and cortisol concentrations near the time of calving, and resulted in greater milk yield during the initial 30 DIM compared with CON.  相似文献   
996.
【摘要】 目的 探讨糖尿病大鼠骨髓来源内皮祖细胞与正常大鼠在数量及生物学活性方面的差异。方法 雄性SD大鼠按60 mg/kg腹腔快速注射1% STZ的枸椽酸缓冲液建立糖尿病动物模型。密度梯度法分离糖尿病大鼠和正常大鼠骨髓单个核细胞,用EGMTM- 2MV BulletKitTM培养基进行诱导培养,观察细胞形态学特征,流式细胞仪检测细胞表面抗原,摄取Dil- Ac- LDL 与结合 FITC- UEA- 1 双荧光鉴定细胞及检测细胞比例,CCK- 8、Transwell小盒等检测细胞增殖、黏附及迁移能力。结果 内皮祖细胞在体外培养时呈梭形,贴壁生长,均可表达CD34、CD133和VEGFR- 2,且能摄取Dil- Ac- LDL并结合FITC- UEA- 1,证明所培养细胞为内皮祖细胞。糖尿病大鼠骨髓来源的内皮祖细胞数目与正常大鼠相比无明显差异,但其黏附能力明显低于正常大鼠,增殖能力、黏附及迁移能力均降低。结论 与正常大鼠相比,糖尿病大鼠骨髓来源内皮祖细胞数量无明显差异,但生物学活性降低,主要表现在增殖能力、黏附及迁移能力均减弱。  相似文献   
997.
目的评价经皮椎体成形术(PVP)临床疗效、适应证及相关技术。方法对295例患者553个椎体在X线C臂血管机导引下行PVP,包括骨质疏松症171例,转移性肿瘤103例,骨髓瘤12例,血管瘤2例,外伤7例。一般采用单侧椎弓根穿刺,骨水泥量为2~7ml 。结果骨质疏松症患者总有效率为94.1%(161/171),转移性肿瘤总有效率为81.5%,骨髓瘤患者有效为8例(8/9),外伤患者有效为7例(7/7)。本组患者无严重并发症;18例转移瘤PVP后3~4d行放射治疗;12例采用大平板血管机旋转X线采集和椎体三维重建成像指导手术操作。结论PVP已成为疼痛性压缩性骨折标准治疗方法之一,伴随手术方法和器材不断改进其适应证必将不断扩大。  相似文献   
998.
目的探讨平阳霉素、利多卡因、碘化油乳剂及经利多卡因浸泡的明胶海绵颗粒栓塞子宫动脉治疗子宫肌瘤的可行性和疗效。方法对68例子宫肌瘤患者应用平阳霉素、利多卡因、碘油乳剂及经利多卡因浸泡的明胶海绵颗粒栓塞治疗,观察术中、术后的疼痛反应、临床症状和肌瘤大小的变化、子宫体积变化及标本病理学表现。结果术中、术后患者疼痛反应较轻,需肌注镇痛剂控制难以忍受疼痛者13例,占19.1%;症状缓解率为92.3%,其中89.5%月经异常得以恢复,盆腔疼痛与腹胀及压迫症状消失达90.8%。3~6个月随防肌瘤平均缩小78.9%,子宫体积平均缩小47.5%。结论平阳霉素、利多卡因、碘油乳剂及经利多卡因浸泡的明胶海绵颗粒是治疗子宫肌瘤较为理想的栓塞材料  相似文献   
999.
The effects of number of homogenization passes, pH, and NaCl concentration on the formation and stability of oil-in-water emulsions comprising a mixture of a biosurfactant (Quillaja bark saponin) and a globular protein (β-lactoglobulin) were investigated. The emulsions were characterized as to visual appearance, droplet size, droplet surface charge, and rheology. The emulsions obtained by different conditions (4, 6, or 8 passes; pH 7, 8, or 9; and 0, 100, or 200 mmol L?1 of NaCl) were polydisperse, presented relatively small average droplet sizes (z-average < 323 nm) as well as negative droplet charge (between –20 and –79.6 mV) in all evaluated conditions. Regardless of the number of homogenization passes, the emulsions exhibited low apparent viscosity and pseudoplastic behavior with small yield stress. Viscoelastic behavior was also observed, thus the emulsions were characterized as weak gels. Four homogenization passes were enough to obtain small droplets in the evaluated conditions. Droplet size was not significantly affected by NaCl concentration and pH (p > 0.05). On the other hand, the absolute ζ-potential values significantly decreased and increased upon increased NaCl content and pH, respectively. Regardless of the tested conditions, all emulsions had good stability against phase separation and droplet aggregation, since no significant changes in average droplet size were observed throughout storage (p > 0.05). In the presence of NaCl, in which droplet charge significantly decreased, emulsion was also stable. Thus, we can conclude that electrostatic repulsion as well as steric repulsion was responsible for stabilization.  相似文献   
1000.
Pedro Ximénez wine, aged by thermal treatment during 10, 20 and 30 days in the presence or absence of oak chips, was studied in terms of antioxidant activity, browning and volatile Maillard compounds. The phenolic fractions obtained by the SepPack tC-18 column revealed that the antioxidant activity after 10 days of thermal treatment was due to the presence of phenols and polar compounds possibly formed by the Maillard reaction. After 30 days, however, the antioxidant activity was also due to high-molecular weight procyanidins. Volatile Maillard compounds increased throughout the thermal treatment. It should be noted that there was an increase in the 5-ethoxymethylfurfural content and the presence of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-2-one, which was recently shown to inhibit growth of colon tumor cells. The presence of oak chips had a substantial effect on the contents in volatile Maillard compounds after the thermal treatment with the exception of corylon. The wine obtained after 10 days of thermal treatment was judged to be the best in terms of sensory properties. In fact, it exhibited the optimum balance between varietal and aging aromas due to Maillard compounds.  相似文献   
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