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61.
62.
Thiiobenzyhdrazide (Htbh) and its Cu(II) complexes, [Cu(Htbh)2Cl2] and [Cu(tbh)2] were synthesized and characterized by various physicochemical studies. In vivo and in vitro antitumour activity of Htbh, [Cu(Htbh)2Cl2] and [Cu(tbh)2] has been tested. LD50 values were calculated for all the three compounds. It was observed that the antitumour effect of [Cu(Htbh)2Cl2] is maximum. Light microscopic study of the treated tumour mass demonstrated that certain cellular degradation, such as disappearance of mitotic figures, loss in cellular compactness, distortion of nucleus and disruption of cytoplasmic boundaries, takes place in the tumour region of complex treated mice. Further, tumour bearing mice administered with Cu(II) complexes showed reversal of tumour growth associated induction of apoptosis in lymphocytes.  相似文献   
63.
In an ongoing effort to discover an effective, topical, dual‐function, non‐surfactant contraceptive vaginal microbicide, a novel series of 2,2′‐disulfanediylbis(3‐(substituted‐1‐yl)propane‐2,1‐diyl) disubstituted‐1‐carbodithioates were designed by using a bioisosterism approach. Thirty‐three compounds were synthesized, and interestingly, most demonstrated multiple activities: they were found to be spermicidal at a minimal effective concentration of 1–0.001 %, trichomonacidal against drug‐susceptible and resistant Trichomonas strains at minimal inhibitory concentration (MIC) ranges of 10.81–377.64 and 10.81–754.14 μM , respectively, and fungicidal at MIC 7.93–86.50 μM . These compounds were also found to be non‐cytotoxic to human cervical (HeLa) epithelial cells and vaginal microflora (Lactobacilli) in vitro. The most promising compound, 2,2′‐disulfanediylbis(3‐(pyrrolidin‐1‐yl)propane‐2,1‐diyl)dipyrrolidine‐1‐carbodithioate ( 5 ), exhibited spermicidal activity 15‐fold higher than that of the marketed spermicide Nonoxynol‐9 (N‐9) and also demonstrated microbicidal potency. To identify common structural features required for spermicidal activity, a 3D‐QSAR analysis was carried out, as well as in vivo efficacy studies and fluorescent labeling studies to determine the biological targets of compound 5 .  相似文献   
64.
BACKGROUND: A survey conducted by the central iodine-deficiency disorders team in Himachal Pradesh, a state in the goiter-endemic belt of India, revealed that 10 of its 12 districts have an endemic prevalence of goiter. The survey was conducted to provide health program managers data to determine whether it would be necessary to initiate intervention measures. OBJECTIVE: To assess the status of urinary iodine excretion and household salt iodization levels after three decades of a complete ban on the sale of noniodized salt in this goiter-endemic state in India as measured by assessment of urinary iodine excretion levels and iodine content of salt at the household level. METHODS: The guidelines recommended by WHO/ UNICEF/ICCIDD for a rapid assessment of salt iodization were adopted. In each of the 12 studied districts, all senior secondary schools were enlisted and one school was selected by using a random sampling procedure. Two hundred fifty children 11 to 18 years of age were included in the study. Urine samples were collected from a minimum of 170 children and analyzed using the wet digestion method. Salt samples were also collected from a minimum of 170 children and analyzed using the spot testing kit. RESULTS: All districts had a median urinary iodine excretion level > 200 microg/L and 82% of the families were consuming salt with an iodine content of 15 ppm or higher. CONCLUSIONS: The results of the present study high-light the successful implementation of the salt iodization program in the state of Himachal Pradesh. This positive impact may be due to the comprehensive strategy adopted by the state government to improve the quality of salt, development of an effective monitoring information system and effective information, education, and communication activities.  相似文献   
65.
The chemical stability and transparency of functional glasses make them a suitable candidate for interactive screen displays, optical grade lenses, etc. Such applications demand glasses with increased scratch resistance to maintain their original optical and mechanical properties. For decades, indentation hardness has been used as a parameter to judge the scratch resistance of glasses. Recent technological advancements in research have shed light on the fundamental difference between the indentation hardness and scratch hardness values. Further, it is also essential to understand the fundamental behavior of glasses under various environments such as abrasive and corrosive conditions. To this extent, this review aims to provide a comprehensive overview of the experimental approaches to quantify and understand the scratch resistance of glasses. Specifically, we introduce the basic differences between indentation and scratch experiments, and various scratch quantification models available in the literature for glasses. We also discuss, in detail, the scratch experiments that have been performed on glasses and the role of various environmental conditions. Overall, through this review article, we outline the understanding on scratch behavior of glasses thus far, thereby, shedding light on the open questions which can enable the design of improved scratch-resistant glasses.  相似文献   
66.
Pastry products are produced from heterogeneous multilayered dough systems. The main ingredients are flour, water, fat and sugar for puff pastry, and the same plus yeast for fermented pastry. Key aspects in pastry production are (i) building laminated dough containing alternating layers of dough and bakery fat and (ii) maintaining this multilayered structure during processing to allow for steam entrapment for proper dough lift during baking. Although most authors agree on the importance of gluten and fat for maintaining the integrity of the different layers, detailed studies on their specific function are lacking. The exact mechanism of steam entrapment during dough lift and the relative contribution of water set free from the fat phase during baking also remain unclear. This review brings together current knowledge on pastry products and the factors determining (intermediate) product quality. Its focus is on flour constituents, fat, water, and (where applicable) yeast during the different production stages of pastry products. Future research needs are addressed as the knowledge on biochemical and physical changes occurring in flour constituents and other ingredients during pastry production and their effect on product quality is currently inadequate.  相似文献   
67.
The reflectance spectra of chirped fiber Bragg gratings can depend substantially on the direction from which the measurement is taken. The measured difference between forward and backward reflectance spectra measured in a linearly chirped grating was shown to be due to the measured excess loss. Simulation using the popular transfer-matrix model demonstrated that the observed asymmetric behavior could be obtained only when excess loss has an asymmetric spectral shape about the local Bragg wavelengths. Application of cladding mode excess losses to the result of a transfer-matrix model accounted for the experimental observation.  相似文献   
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69.
The alloys of Fe–6Si–8B and Fe–6Si–8B–1Mn were prepared using high energy planetary ball mill. X-ray diffraction patterns of the milled samples confirmed the formation of the alloys by dissolution of Si in Fe after 30 and 24 h of milling for the Fe–6Si–8B and Fe–6Si–8B–1Mn samples respectively. The lattice parameter was found to increase continuously with milling time and the rise was steeper for the quaternary alloy. After 36 h of milling, the crystallite size for the two samples were reduced to 98 and 86 nm respectively. Mössbauer spectra suggested the formation of minor amount of α-Fe2O3. The value of saturation magnetization was 162 Am2/kg for Fe–6Si–8B alloy obtained after 18 h of milling. However, the value decreased with increased milling time as well as with Mn-addition. The remanance value showed similar tendency as that for saturation magnetization. In contrast, the coercivity value was found to be increasing with milling time and with Mn-addition.  相似文献   
70.
During mammalian spermatogenesis, the chromatin of the spermatogenic cells is profoundly reorganized. Somatic histones are partly replaced by testis-specific histones. These histones are then replaced by transition proteins and finally by protamines. This series of nucleoprotein rearrangements results in a highly condensed sperm cell nucleus. In contrast to spermatozoa from other species, human spermatozoa still contain a significant amount of histones, including testis-specific histone 2B (TH2B). In the present study it is shown that an antibody targeting tyrosine hydroxylase, which has been found previously to cross-react with rat TH2B, also specifically immunoreacts with human TH2B on Western blots, in immunohistochemistry of human testis tissue, and in immunocytochemistry of decondensed human spermatozoa. In human testis tissue, TH2B immunostaining first apparent in spermatogonia, shows marked variation, especially at the pachytene spermatocyte stage, and then reaches an intense signal in round spermatids. Shortly before spermatid elongation, a portion of the spermatid nucleus, corresponding to the acrosomal region, loses its immunoreactivity. During condensation of the spermatid nucleus, the immunodetectability of TH2B disappears gradually, from the anterior region of the nucleus onwards. At the final stages of spermiogenesis, the immunostaining is completely absent. Immunocytochemical staining of spermatozoa revealed no TH2B immunosignal, but immunostaining was observed when spermatozoa obtained from semen were decondensed to make nuclear proteins accessible to the antibody. There was, however, a striking intercellular variability in the intensity of staining of spermatozoa within an ejaculate. In a population of 35 men attending our Andrology Clinic, we observed interindividual differences in total sperm TH2B content, which showed a significant, although not very pronounced, negative correlation with normal morphology (P = 0.05).  相似文献   
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