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The integrin alpha 4 beta 7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are molecules involved in the normal recirculation of lymphocytes between the blood and the gastrointestinal tract. These molecules may play a complementary and significant role in animal models of colitis. We have investigated the structural interaction between alpha 4 beta 7 and MAdCAM-1. Site-directed mutagenesis studies of the MAdCAM-1 molecule has led to the identification of the amino acid residue (LDT) in the loop between beta strands C and D of the Ig-superfamily-like folds being involved in the adhesive and cell activation functions of MAdCAM-1 with alpha 4 beta 7.  相似文献   
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OBJECTIVES: To explore 2 facets of dopamine receptor sensitivity in alcoholics: (1) whether reduced sensitivity of central dopamine receptors is correlated with anxiety, depression, or novelty seeking and (2) whether this reduction is associated with poor treatment outcome. METHOD: Sixty-four alcohol-dependent patients were assessed according to their clinical outcome, sensitivity of central dopamine receptors (apomorphine-induced growth hormone secretion), mood states, and personality traits before and after detoxification. RESULTS: Patients with poor treatment outcome displayed a blunted growth hormone response before, but not after, detoxification. Growth hormone response was not significantly correlated with novelty seeking. Relapsing patients tended to be less depressed than patients who remained abstinent during observation. CONCLUSION: This study did not support the hypothesis that reduced sensitivity of dopamine receptors is associated with anxiety, depressed mood, or high novelty seeking in alcoholism.  相似文献   
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Recent scientific studies have demonstrated the efficacy of various forms of immunotherapy for the treatment of allergic diseases. Traditional subcutaneous immunotherapy, sublingual, oral, and intranasal immunotherapy have been shown to significantly reduce symptoms and favorably modulate the immune response. Outcome studies that use patient response data from standardized surveys represent the next challenge to all practicing allergists.  相似文献   
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Y chromosome deletions encompassing the AZFc region have been reported in 13% of azoospermic men and 7% of severely oligozoospermic men. We examined the impact of these Y deletions on the severity of testicular defects in 51 azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after testicular sperm extraction (TESE) and 30 men with severe oligozoospermia undergoing ICSI after ejaculation of spermatozoa. In addition, five azoospermic patients shown previously to have Y chromosome deletions underwent histological evaluation of their previously obtained testis biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y chromosome AZFc region. Of these 10, five had spermatozoa retrievable from the testis, and in two cases the wives became pregnant. Of the 41 azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa retrievable from the testis, and in 12 cases (29%) the wives became pregnant. Four of 30 (13%) severely oligozoospermic patients were found to be deleted for AZFc and in three (75%) of these pregnancy was achieved. The other 26 severely oligozoospermic couples who had no AZFc deletions underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The embryo implantation rate was not significantly different for azoospermic (22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the total of 19 infertile men who had Y chromosome deletions, 14 had deletions within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14 had some spermatozoa (however few in number) in the ejaculate or testis. Five of the Y-deleted men had deletions that extended more proximally on the Y chromosome, and in none of these could any spermatozoa be observed in either ejaculate or testis. These results support the concept that, in azoospermic or oligozoospermic men with Y chromosome deletions limited to intervals 6D-6F (AZFc), there are generally very small numbers of testicular or ejaculated spermatozoa. Larger Y deletions, including and extending beyond the AZFc region and encompassing more Y genes, tend to be associated with a total absence of testicular spermatozoa. In those cases where spermatozoa were retrieved, the presence of Y deletions had no obvious impact on fertilization or pregnancy rate.  相似文献   
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ALX40-4C is an antiretrovirus agent that has been found to have some inhibitory properties against human immunodeficiency virus (HIV) replication in vitro. The compound was designed as a competitor of the HIV Tat protein for TAR binding. In addition to its anti-HIV properties, it has demonstrated the ability to inhibit in vitro replication of herpes simplex virus types 1 and 2 as well as human cytomegalovirus. Subsequently, in vivo pharmacokinetic evaluation of ALX40-4C necessitated the establishment of a detection system for the measurement of ALX40-4C in subject serum. For this purpose, an indirect-competition enzyme-linked immunosorbent assay with generated rabbit anti-ALX40-4C antiserum was developed. The original assay took 12 h to complete and required many manipulations. Herein, we describe alterations to the system that resulted in the overall reduction in assay time and manipulation. We demonstrate that our alterations do not affect the specificity or sensitivity of the assay compared to that of the original system. ALX40-4C levels in spiked serum samples as well as drug levels from patient samples were used to validate the assay.  相似文献   
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BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) strains can be genetically classified into genetic lineages known as genetic types or subtypes according to phylogenetic analyses of complete or partial nucleotide sequences of their genomes. The genetic classification of HIV-1 and HCV strains has important implications for the development of globally effective vaccines and for the management of patients. MATERIALS AND METHODS: A new method, termed combinatorial DNA melting assay (COMA), allows rapid accessing of comparative genetic information between related DNA sequences, making it possible to rapidly and accurately genotype unknown HIV-1 and HCV strains. COMA is mainly based on the differential melting properties of long DNA heteroduplexes. Combinatorial arrays of DNA heteroduplexes are formed when captured PCR-amplified reference DNA with known nucleotide sequences are combined with solution-phase complementary and antigenically labeled DNA with unknown sequences. Genetic divergence between the known and the unknown sequences is inferred as the experimentally derived melting curves of the two strands of the DNA heteroduplexes increasingly diverge. RESULTS: COMA was successfully applied to the genetic classification of HIV-1 and HCV strains into phylogenetic lineages or subtypes. CONCLUSIONS: Use of this assay should accelerate current efforts to understand the global molecular epidemiology of HIV-1 and HCV and may extend to the genetic characterization of other genetically diverse infectious pathogens associated with numerous diseases.  相似文献   
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