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991.
992.
The goal of this study was to determine the frequency and methods of intraoperative fetal and uterine monitoring during maternal surgery in the United States. Maternal surgery was defined as nonobstetric surgery during pregnancy that required general or regional anesthesia. We mailed a 21-item questionnaire to the perioperative nurse managers of US hospitals at which more than 2,000 babies are delivered annually (n = 579). Nearly 60% of responding hospitals routinely used some form of fetal monitoring during maternal surgery; more than 40% of responding hospitals did not use intraoperative fetal and uterine monitoring routinely during maternal surgery.  相似文献   
993.
In this paper we investigate the important contribution of multiple public health surveillance systems to policy in chronic disease control and prevention. We show that, typically, surveillance for chronic diseases relies on multiple data sources, often created for another purpose. We also define the concept of burden for chronic conditions based on data from multiple sources. An example from a state illustrates a model for combining data for use in policy development. These applications illustrate the central role of statistical methods in ensuring the appropriate use of data from multiple surveillance systems.  相似文献   
994.
Bone formation is linked closely to angiogenesis. Because prostaglandin E2 (PGE2) is a potent stimulator of bone formation, its effects were evaluated on vascular endothelial growth factor, a secreted endothelial cell-specific mitogen, and a potent angiogenic protein. Prostaglandin E2 increased vascular endothelial growth factor protein in conditioned media of osteoblastic RCT-3 cells within 3 hours. Prostaglandin E2 also increased the steady-state levels of vascular endothelial growth factor mRNA in a dose-dependent manner. The increased expression of vascular endothelial growth factor mRNA produced by PGE2 was rapid (maximal at 1 hour) and was enhanced by the protein synthesis inhibitor cycloheximide (5 micrograms/ml). The increase in vascular endothelial growth factor mRNA by PGE2 was inhibited strongly by pretreatment for 3 hours with dexamethasone (10(-7) M). Stimulation of vascular endothelial growth factor by PGE2 and its suppression by dexamethasone implicate the involvement of vascular endothelial growth factor in bone metabolism.  相似文献   
995.
The specialized reproductive functions of angiosperm pistils are dependent in part upon the regulated activation of numerous genes expressed predominantly in this organ system. To better understand the nature of these pistil-predominant gene products we have analyzed seven cDNA clones isolated from tomato pistils through differential hybridization screening. Six of the seven cDNAs represent sequences previously undescribed in tomato, each having a unique pistil- and/or floral-predominant expression pattern. The putative protein products encoded by six of the cDNAs have been identified by their similarity to sequences in the database of previously sequenced genes, with a seventh sequence having no significant similarity with any previously reported sequence. Three of the putative proteins appear to be targeted to the endomembrane system and include an endo-beta-1,4-glucanase which is expressed exclusively in pistils at early stages of development, and proteins similar in sequence to gamma-thionin and miraculin which are expressed in immature pistils and stamens, and in either sepals or petals, respectively. Two other clones, similar in sequence to each other, were expressed primarily in immature pistils and stamens and encode distinct proteins with similarity to leucine aminopeptidases. An additional clone, which encodes a protein similar in sequence to the enzyme hyoscyamine 6-beta-hydroxylase and to other members of the family of Fe2+/ascorbate-dependent oxidases, was expressed at high levels in pistils, stamens and sepals, and at detectable levels in some vegetative organs. Together, these observations provide new insight into the nature and possible functional roles of genes expressed during reproductive development.  相似文献   
996.
BACKGROUND & AIMS: Secretory mucins play an important role in gastric cytoprotection and are derived from a heterogeneous family of genes. The aim of this study was to determine the specific type and location of mucin gene expression in the human stomach. METHODS: Expression cloning was performed by screening a human gastric complementary DNA expression library with antisera against deglycosylated gastric mucin. RNA analysis and immunohistochemistry were used to quantify and localize mucin gene expression. RESULTS: Sequencing of positive clones revealed two clones containing tandem repeats. The first contained a 169-amino acid repeat and was named MUC6 (as previously described). The second contained the same 8-amino acid repeat consensus sequence (APTTSTTS) as complementary DNAs previously isolated from a tracheobronchial complementary DNA library and was labeled MUC5 (or MUC5AC). RNA analysis indicated that the gastric epithelium contains high levels of MUC5 and MUC6 messenger RNA with little or no MUC2, MUC3, and MUC4 messenger RNA. Immunohistochemical analysis showed that surface mucous cells of the cardia, fundus, and antrum expressed MUC5 peptide. In contrast, MUC6 peptide expression was limited to mucous neck cells of the fundus, antral-type glands of the antrum and cardia, and Brunner's glands of the duodenum. CONCLUSIONS: MUC5 and MUC6 represent major secretory mucins in the stomach and are localized to distinct cell types.  相似文献   
997.
AMS is a preventable disease about which travellers are frequently uninformed and one which physicians may wrongfully assume is limited to the population of ultra high altitude adventurers. These studies on incidence, while not without flaws, point out the frequency of AMS, as well as its significant incidence at moderate and commonly frequented altitudes. The current literature does not fully answer questions about incidence at moderate altitudes, nor about the full effects of altitude on children. Certainly AMS is not a rare complication of travel to altitudes and may indeed be under-recognized and under-treated. Both acetazolamide and dexamethasone provide adequate prophylaxis, and the choice of medications can be to some extent based on experience and patient profile. The best prophylaxis is a slow stepwise ascent, and the best treatment descent. The availability of medications for the amelioration or prevention of symptoms, and succinct advice on prevention by travel planning will make many of our patients' holidays more enjoyable and business trips more productive.  相似文献   
998.
BACKGROUND: Nosocomial infections are a major cause of morbidity and mortality in premature infants. As a rule, their low serum gamma globulin levels at birth subsequently decline to hypogammaglobulinemic values; hence, prophylactic administration of intravenous immune globulin may reduce the rate of hospital-acquired infections. METHODS: In this prospective, multicenter, two-phase controlled trial, 2416 infants were stratified according to birth weight (501 to 1000 g and 1001 to 1500 g) and randomly assigned to an intravenous immune globulin group (n = 1204) or a control group (n = 1212). Control infants were given placebo infusions during phase 1 of the study (n = 623) but were not given any infusions during phase 2 (n = 589). Infants weighing 501 to 1000 g at birth were given 900 mg of immune globulin per kilogram of body weight, and infants weighing 1001 to 1500 g at birth were given a dose of 700 mg per kilogram. The immune globulin infusions were repeated every 14 days until the infants weighed 1800 g, were transferred to another center, died, or were sent home from the hospital. RESULTS: Nosocomial infections of the blood, meninges, or urinary tract occurred in 439 of the 2416 infants (18.2 percent): 208 (17.3 percent) in the immune globulin group and 231 (19.1 percent) in the control group (relative risk, 0.91; 95 percent confidence interval, 0.77 to 1.08). Septicemia occurred in 15.5 percent of the immune globulin recipients and 17.2 percent of the controls. During phase 1 the rate of nosocomial infections was 13.4 percent in the immune globulin group and 17.8 percent in the control group; the respective rates during phase 2 were 21.0 percent and 20.4 percent. The predominant organisms included gram-positive cocci (53.0 percent), gram-negative bacilli (22.4 percent), and candida species (16.0 percent). Adverse reactions were rarely observed during the infusions. Immune globulin therapy had no effect on respiratory distress syndrome, bronchopulmonary dysplasia, intracranial hemorrhage, the duration of hospitalization, or mortality. The incidence of necrotizing enterocolitis was 12.0 percent in the immune globulin group and 9.5 percent in the control group. CONCLUSIONS: Prophylactic use of intravenous immune globulin failed to reduce the incidence of hospital-acquired infections in very-low-birth-weight infants.  相似文献   
999.
Satellite panicum mosaic virus (SPMV) has been purified from pearl millet and obtained in a variety of different crystal forms, at least two of which appear suitable for high resolution X-ray diffraction analysis. The first is of cubic space group P4(2)32 with a = b = c = 183.1 A and two virus particles in the unit cell. The second is of a primitive orthorhombic space group with a = 166.1 A, b = 266.7 A and c = 269.1 A, with four virus particles in the unit cell. While the cubic crystal has as its asymmetric unit one twelfth of the icosahedron, or five capsid protein subunits, the asymmetric unit of the orthorhombic crystals is an entire particle. The cubic crystals diffract to at least 2.8 A resolution. We have also succeeded in crystallizing, but not yet characterizing the master virus, PMV.  相似文献   
1000.
Cryptomonads are unicellular algae with plastids surrounded by four membranes. Between the two pairs of membranes lies a periplastidal compartment that harbours a DNA-containing organelle, termed the nucleomorph. The nucleomorph is the vestigial nucleus of a phototrophic, eukaryotic endosymbiont. Subcloning of parts of one nucleomorph chromosome revealed a gene coding for an Hsp70 protein. We demonstrate the expression of this nucleomorph protein-coding gene and present a model for protein transport from the host to the endosymbiont compartment.  相似文献   
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