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101.
Some key issues regarding gender differences in the prevalence of mental disorders, the course of mental illness, and the use of services are reviewed, along with their diagnosis and psychopharmacologic treatment. Implications for clinical practice are examined, as are directions for future research that will ensure the presence of women's mental health as a major element in the national agenda on women's health.  相似文献   
102.
The ability to resolve isomeric protonated dipeptides was investigated with the new technique of differential ion mobility mass spectrometry that uses "modifier" molecules to enhance differential mobility. Two pairs of protonated peptides [glycine-alanine (GlyAla) and alanine-glycine (AlaGly), glycine-serine (GlySer) and serine-glycine (SerGly)] and eight different modifiers (water, 2-propanol, 1,5-hexadiene, 2-chloropropane, chlorobenzene, dichloromethane, acetonitrile, and cyclohexane) were used in the initial study. Separation of the protonated peptides was found to be dependent on the mass and proton affinity of the modifier and combinations of functionalities present in the modifier and the analyte ion. Six of the eight modifiers (water, 2-propanol, chlorobenzene, cyclohexane, dichloromethane, and acetonitrile) were able to separate the protonated isomeric peptide pairs, and generally, modifiers with electron-rich groups performed the best. In the presence of some modifiers, a reduction of ion current was observed under the highest field conditions (>115 Td). Dopant-catalyzed isomerization, likely by proton-transport catalysis, and field-induced fragmentation may have contributed to these losses. Two high vapor pressure modifiers, 1,5-hexadiene and 2-chloropropane, significantly influenced ion formation leading to the formation of stable cluster populations that could be observed in the mass spectrometer. Although not a major concern, both fragmentation and influence of modifier evaporation warrant further studies in order to fully understand and possibly eliminate them.  相似文献   
103.
Increased cardiovascular mortality occurs in diabetic patients with or without coronary artery disease and is attributed to the presence of diabetic cardiomyopathy. One potential mechanism is hyperglycemia that has been reported to activate protein kinase C (PKC), preferentially the beta isoform, which has been associated with the development of micro- and macrovascular pathologies in diabetes mellitus. To establish that the activation of the PKCbeta isoform can cause cardiac dysfunctions, we have established lines of transgenic mice with the specific overexpression of PKCbeta2 isoform in the myocardium. These mice overexpressed the PKCbeta2 isoform transgene by 2- to 10-fold as measured by mRNA, and proteins exhibited left ventricular hypertrophy, cardiac myocyte necrosis, multifocal fibrosis, and decreased left ventricular performance without vascular lesions. The severity of the phenotypes exhibited gene dose-dependence. Up-regulation of mRNAs for fetal type myosin heavy chain, atrial natriuretic factor, c-fos, transforming growth factor, and collagens was also observed. Moreover, treatment with a PKCbeta-specific inhibitor resulted in functional and histological improvement. These findings have firmly established that the activation of the PKCbeta2 isoform can cause specific cardiac cellular and functional changes leading to cardiomyopathy of diabetic or nondiabetic etiology.  相似文献   
104.
OBJECTIVE: This study assessed the clinical performance of dentin-bonded crowns, in which ceramic crowns are bonded to underlying dentin with a resin composite-based luting material and a dentin bonding agent. METHOD AND MATERIALS: Twenty-five patients who had received such restorations more than 1 year previously were recalled for evaluation of their crowns. RESULTS: Sixty dentin-bonded complete-coverage restorations were assessed. Forty-one of the crowns had been placed on incisor teeth. The mean time since placement of the restorations was 2.43 years. Fifty-seven of the 60 restorations were intact. The three failures had resulted from cracks in the restorations, which had not clinically debonded. No secondary caries was detected at the crown margins, and anatomic form was assessed as excellent for 56 crowns. Root canal treatment had been required in one case. Color match was rated very good for 47 crowns. All 25 patients were satisfied with their restorations. CONCLUSION: Dentin-bonded crowns may be found to have a low rate of failure and to provide a high level of patient satisfaction.  相似文献   
105.
Recently, cDNAs encoding brain-specific transmembrane-type protein tyrosine phosphatases (PTPs) with single catalytic domain have been cloned. These include PC12-PTP, PCPTP1, PTPBR7, and PTP-SL, whose cytoplasmic domains had high similarity to STEP, a brain-specific nontransmembrane-type PTP. Based on the high similarity and expression pattern, PCPTP1 seems to be identical with PC12-PTP1 and to be the rat homologue of murine PTPBR7. Here, we report the molecular cloning and expression profile of PCPTP1-Ce, a variant of PCPTP1. Both PCPTP1 mRNA and PCPTP1-Ce mRNA seem to be derived from a single common region gene. Nucleotide and deduced amino acid sequence comparison between PCPTP1-Ce and PCPTP1 revealed that the predicted protein product of PCPTP1-Ce is identical with that translated from the third initiation methionine of the longest ORF of PCPTP1, and that these two clones differ in the 5'-untranslated sequences. Northern blot analyses with specific probes for PCPTP1 and PCPTP1-Ce confirmed our previous observation that PCPTP1-Ce mRNA was almost exclusively expressed in the cerebellum, whereas PCPTP1 was widely expressed in various brain regions dissected including cerebellum. In situ hybridization study demonstrated that PCPTP1-Ce mRNA was exclusively expressed in Purkinje cells of the cerebellum. In contrast, PCPTP1 mRNA was predominantly expressed in granule cells and less in Purkinje cells. Moreover, immunohistochemical analysis using an affinity-purified polyclonal antibody raised against the cytoplasmic region of PCPTP1/PCPTP1-Ce demonstrated that Purkinje cells were strongly immunostained, whereas granule cells were stained only faintly in the cerebellum. These observations clearly demonstrated that PCPTP1-Ce mRNA and its protein products are expressed in Purkinje cells and suggest that PCPTP1-Ce may play an important role in Purkinje cell function in the rat cerebellum.  相似文献   
106.
A model of chronic infection of primary cultures of suckling mouse brain (SMB) cells actively producing hepatitis C virus (HCV) is developed. Destruction and repopulation of cells was observed for at least 6 months; this phenomenon was paralleled by virus release in culture medium. Persistent HCV contained in SMB cultures induced a cytopathogenic effect in PS, BHK-21, Vero, HAK, and click embryo cell cultures, its infective titers being 10.0-12.0 lg TCD50/0.2 ml. Persistent HCV formed heterogeneous plaques under agar in chick embryo cells. The polymerase chain reaction (PCR) regularly detected the HCV RNA at the stage of cell destruction in the culture fluid of HCV-infected cell cultures. The cytopathogenic activity of persistent HCV was neutralized by anti-HCV positive patients' sera with the neutralization index of 8.0-9.0 lg. The results of persistent HCV neutralization were confirmed by PCR. Immunofluorescence detected virus-specific HCV antigens in 15-40% of infected cells. Hence, the SMB-HCV system realized the cytopathogenic potential of HCV circulating in the blood of patients with hepatitis C. This system is promising for the study of the pathogenesis of HCV infection at a cellular level, for screening for specific and nonspecific antiviral agents, and for preparing native virus-specific proteins and RNA.  相似文献   
107.
DK Rajan  DL Croteau  SG Sturza  ML Harvill  CJ Mehall 《Canadian Metallurgical Quarterly》1998,18(5):1155-67; discussion 1167-70
Access to the central venous circulation for hemodialysis has traditionally been achieved via the subclavian or jugular venous routes. With ongoing improvements in medical management, many hemodialysis recipients develop exhaustion of these routes and require alternative means of central venous access. Inferior vena caval (IVC) catheters have been placed with a percutaneous translumbar approach to allow central venous access for chemotherapy, harvesting of stem cells, and total parenteral nutrition. Translumbar placement of IVC catheters has become accepted by some as a useful and reliable alternative in patients who require long-term hemodialysis but have exhausted traditional access sites. IVC catheters have been placed in patients with IVC filters, and IVC filters have been placed in patients with IVC catheters. Complications include those associated with central venous catheters, for example, sepsis, fibrin sheaths, and thrombosis. A complication specific to placement of IVC hemodialysis catheters is migration of the catheter into the subcutaneous soft tissues, retroperitoneum, or iliac veins. Translumbar placement of IVC catheters is performed only in patients considered to have few or no other medical options and is not intended as a primary means of central venous access.  相似文献   
108.
The antitumour effect of tea plant root extract (TRE) has been evaluated against Ehrlich ascites carcinoma (EAC) in Balb-C mice. Significant increases of survival times of the TRE-treated, tumour-bearing mice have been confirmed repeatedly with respect to the control group. TRE inhibited the tumour cell growth and reversed the changes of haematological parameters consequent to tumour inoculation.  相似文献   
109.
The conserved residue Asp477 in yeast transketolase is located in the substrate channel of the enzyme and forms a hydrogen bond with the C2-hydroxyl group of the acceptor substrate. The significance of this interaction for the recognition of the preferred acceptor substrates, D-alpha-hydroxyaldehydes was investigated by site-directed mutagenesis. In the wild-type enzyme the kcat/KM values are by three to four orders of magnitude lower for 2-deoxyaldoses or substrates with L-configuration at the C2-atom. In the Asp477 Ala mutant, the kcat/KM values for D-alpha-hydroxyaldehydes are decreased by a thousandfold, while the kcat/KM values for substrates with L-configuration or 2-deoxyaldoses are similar to wild-type enzyme. These results indicate that Asp477 is involved in determining the enantioselectivity of transketolase.  相似文献   
110.
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