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131.
We evaluated the data of the National Collegiate Athletic Association Injury Surveillance System on collegiate wrestling with a focus on musculoskeletal injuries. Over 800,000 athlete-exposures during an 11-year period compose these data. Findings particular to wrestling and a comparison with other collegiate sports are included. Collegiate wrestling had a relatively high rate of injury at 9.6 injuries per 1000 athlete-exposures. It was second to spring football in total injury rate. Most injuries in this study were not serious, with 6.3% resulting in surgery and 37.6% resulting in a week or more off from wrestling. There was only one catastrophic, nonfatal injury. The knee, shoulder, and ankle were the most commonly injured regions, and injuries to them were often the more serious. Sprains, strains, and contusions were the most common injury types. Takedowns and sparring were the most common activities at the time of injury. Mechanism of injury was evaluated; rotation about a planted foot and contact with environmental objects were identified as areas needing further attention. Illegal action accounted for only 4.6% of injuries in competition. Competition had a significantly higher injury rate than practice, but the injury profiles of these two areas showed both to be equally important. The preseason and regular season had higher injury rates than the postseason, but, again, the injury profiles of these periods were similar. Injury percentages were similar among the 10 weight classes.  相似文献   
132.
Insights into Src kinase functions: structural comparisons   总被引:1,自引:0,他引:1  
Recent structures of Src tyrosine kinases reveal complex mechanisms for regulation of enzymatic activity. The regulatory SH3 and SH2 domains bind to the back of the catalytic kinase domain via a linker region that joins the SH2 domain to the catalytic domain. Members of a subgroup of the Src kinase family show distinct features in this linker and in the loops that interact with it. Hydrophobicity of key residues in this region is important for intramolecular regulation. The kinases Abl, Btk and Csk seem to have the same molecular architecture as Src. Structural comparisons between serine/threonine and tyrosine kinases indicate a specific twisting mechanism involving the N- and C-terminal lobes of the catalytic domain. This motion could provide insights into the various mechanisms used to regulate kinase activity.  相似文献   
133.
BACKGROUND AND OBJECTIVE: Experience with recombinant human erythropoietin (rHuEPO) in the treatment of the anemia secondary to myelofibrosis with myeloid metaplasia (MMM) is slight up to now. We present our results of the treatment of 6 patients and a review of the literature in search of possible parameters predicting response to this treatment. DESIGN AND METHODS: From January 1994 to June 1996 all transfusion-dependent patients with MMM diagnosed in our hospital were included in this study. We established a minimum period of 4 weeks of treatment and a maximum of 12 if no response was observed. Initial dosages used were 100 U/kg s.c. 3 times weekly, increasing by 50 U/kg every 4 weeks where no response was observed. Response was defined as a reduction > or = 30% of the previous transfusional needs. The review of the literature was made using a MEDLINE search (January 1990-December 1996) on the keywords erythropoietin, myelofibrosis, and agnogenic myeloid metaplasia. A statistical study was made in search of possible parameters to predict response. The parameters studied include age, sex, hemoglobin, serum erythropoietin (sEPO) levels, transfusional dependency, transfusional requirements per month prior to treatment, maximum dosages used and dosage at which response was obtained. RESULTS: Only 2 of our 6 patients responded, both at a dosage of 600 U/kg/week (200 U/kg 3 times weekly s.c.). In addition to our 6 patients we have found only 28 other patients in the literature. For statistical calculation 2 of our patients were not considered as they did not complete the period of study. The overall rate of response was 17/32 (53.1%). In the univariate analysis comparing responders and non-responders we found a tendency to significance with respect to sex (p = 0.07), sEPO (p = 0.07) and transfusional needs in units of packed red blood cells per month (PRBC/m) (p = 0.13). In this way patients with low sEPO, females and those with low transfusional needs (< 3 PRBC/m) respond better. This better response in females could be explained by the fact that their disease situation was more stable (with both lower sEPO levels and transfusional dependency). The best cut-off point in the sEPO to predict response was 123 mU/mL. No important side-effects have been observed except three cases of aggravation of splenomegaly. In two cases this condition improved when the rHuEPO was discontinued. The association of rHuEPO with hydroxyurea or interferon does not seem to affect the response. INTERPRETATION AND CONCLUSIONS: Though the number of patients is low, our data suggest that some MMM patients, in particular females and individuals with low sEPO levels and with low transfusional needs, might benefit from rHuEPO in terms of elevation of hemoglobin levels. Unfortunately, transfusion dependent-patients, i.e. those in whom a beneficial effect of rHuEPO would be most welcome, are unlikely to respond, and more generally, treatment is not cost effective in medically responsive patients.  相似文献   
134.
Hypersensitivity syndrome (HSS) usually refers to severe drug eruption associated with systemic symptoms and eosinophilia. Interleukin (IL)-5 regulates eosinophil counts with the help of IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF). Blood IL-5 levels have been reported to be increased in patients with eosinophilia secondary to parasitic infections or idiopathic eosinophilia, but have never been evaluated in drug-induced eosinophilia. The aim of our study was to determine whether IL-5, IL-3 and GM-CSF are involved in eosinophilia in patients with drug-induced HSS. Plasma levels of IL-3, IL-5 and GM-CSF were assayed by ELISA in seven patients with drug-induced HSS, in eight patients with cutaneous adverse drug reactions not associated with eosinophilia, and in five patients with eosinophilia unrelated to drug treatment. IL-5 levels were normal in all eight patients with drug eruptions without eosinophilia, and increased in five of the seven patients with HSS. In the latter patients, IL-5 levels peaked several days before highest eosinophil counts were noted, and returned to normal within a few days, even when eosinophilia persisted. In patients with eosinophilia unrelated to drug treatment, IL-5 levels, although significantly increased remained lower than in HSS patients. IL-3 and GM-CSF could not be detected in any group, at any time. Our results show that IL-5 is involved in drug-related eosinophilia. As IL-5 production was only involved in the early stages of the reaction, it is suggested that IL-5 mainly derives from activated lymphocytes rather than eosinophils. Our results support the clinical relevance of previous in vitro findings. Further studies are needed to test whether assays of IL-5 production by lymphocytes of patients stimulated by the suspected drug and/or its metabolites, are useful in establishing causality in drug-induced reactions associated with eosinophilia.  相似文献   
135.
Strobe rearing prevents the convergence of inputs with different response timings onto area 17 simple cells. J. Neurophysiol. 80: 3005-3020, 1998. The preceding paper showed that the loss of direction selectivity in simple cells induced by strobe rearing reflects the elimination of spatially ordered response timing differences across the receptive field that underlie spatiotemporal (S-T) inseparability. Here we addressed whether these changes reflected an elimination of certain timings or an alteration in how timings were associated in single cells. Timing in receptive fields was measured using stationary bars undergoing sinusoidal luminance modulation at different temporal frequencies (0.5-6 Hz). For each bar position, response phase versus temporal frequency data were fit by a line to obtain two measures: absolute phase and latency. In normal cats, many individual simple cells display a wide range of timings; in layer 4, the mean range for absolute phase and latency was 0.21 cycles and 39 ms, respectively. Strobe rearing compressed the mean timing ranges in single cells, to 0.08 cycles and 31 ms, respectively, and this compression accounted for the loss of inseparability. A similar compression was measured in layer 6 cells. In contrast, the range of timing values across the simple-cell population was relatively normal. Single cells merely sampled narrower than normal regions of the timing space. We sought to understand these cortical changes in terms of how inputs from the lateral geniculate nucleus (LGN) may have been affected by strobe rearing. In normal cats, a wide range of absolute phase and latency values exists among lagged and nonlagged LGN cells, and these thalamic timings account for most of the cortical timings. Also, S-T inseparability in many simple cells can be attributed to the convergence of lagged and/or nonlagged inputs. Strobe rearing did not change the sampling of lagged and nonlagged cells, and the geniculate timings continued to account for most of the cortical timings. However, strobe rearing virtually eliminated cortical receptive fields with mixed lagged and nonlagged timing, and it compressed the timing range in cells dominated by one or the other geniculate type. Thus strobe rearing did not eliminate certain timings in LGN or cortex, but prevented the convergence of different timings on single cells. To account for these results, we propose a developmental model in which strobe stimulation alters the correlational structure of inputs based on their response timing. Only inputs with similar timing become associated on single cortical cells, and this produces S-T separable receptive fields that lack the ability to confer a preferred direction of motion.  相似文献   
136.
137.
A review of the biomedical literature suggests that lymphocyte and neutrophil counts are probably the only blood cell count parameters whose independent pre-therapeutic prognostic values are significantly documented in lung cancer (and only in non small cell lung cancer). The independent pre-therapeutic prognostic value of these two parameters remains quite controversial however, and further studies should be conducted, and in particular, comparisons between neutrophils, lymphocytes, and serum cyfra 21-1. For the therapeutic follow-up, further prognostic evaluation studies are also necessary for blood cell count parameters as well as for serum cyfra 21-1. Clinical biologists still have to convince clinicians and/or journal editors that it is not scientifically acceptable for publications to omit detailing the analytical and pre-analytical methodologies used for blood cell count measurements.  相似文献   
138.
Analogues of 3-amino-7-(2,6-dichlorobenzyl)-6-methyltriazolo[4,3-b]pyridazine PC25 containing amide or carboxylic acid function were synthesized and tested for anticonvulsant activity. The compounds having the imidazole ring substituted with an amide group have been found to be generally more active against maximal electroshock-induced seizures in mice (15.2 < or = ED50 < or = 37.5 mg kg(-1) orally). Furthermore, maximum activity was generally associated with a 2,6-dichlorobenzyl substitution pattern. 3-Amido-7-(2,6-dichlorobenzyl)-6-methyltriazolo[4,3-b]pyridazine 4b was also protective in the pentylenetetrazole-induced seizures test (ED50 = 91.1 mg kg(-1) orally) and blocked strychnine-induced tonic extensor seizures (ED50 = 62.9 mg kg(-1) orally). Moreover, calculated electrostatic isopotential maps of the whole active compounds were quite similar and, consequently, could be associated to optimum anticonvulsant activity.  相似文献   
139.
Metastasis to the orbit from pancreatic adenocarcinoma is rare. A 38-year-old man with metastatic adenocarcinoma of the right orbit at initial examination is described. Two months later he was diagnosed with a pancreatic primary tumor. The incidence and pattern of orbital metastasis in carcinomas is briefly discussed.  相似文献   
140.
Survivin is a member of the inhibitor of apoptosis protein (IAP) family. We investigated the antiapoptotic mechanism of Survivin, as well as its expression in 60 human tumor cell lines used for the National Cancer Institute's anticancer drug screening program. In cotransfection experiments, cell death induced by Bax or Fas (CD 95) was partially inhibited (mean +/- SD, 65% +/- 8%) by Survivin, whereas XIAP, another IAP family member, almost completely blocked cell death (93% +/- 4%) under the same conditions. Survivin and XIAP also protected 293 cells from apoptosis induced by overexpression of procaspase-3 and -7 and inhibited the processing of these zymogens into active caspases. In vitro binding experiments indicated that, like other IAP-family proteins, Survivin binds specifically to the terminal effector cell death proteases, caspase-3 and -7, but not to the proximal initiator protease caspase-8. Using a cell-free system in which cytosolic extracts were derived from control- or Survivin-transfected cells and where caspases were activated either by addition of cytochrome c and dATP or by adding recombinant active caspase-8, Survivin was able to substantially reduce caspase activity, as measured by cleavage of a tetrapeptide substrate, AspGluValAsp-aminofluorocoumarin. Similar results were obtained in intact cells when Survivin was overexpressed by gene transfection and caspase activation was induced by the anticancer drug etoposide. Survivin was expressed in all 60 cancer cell lines analyzed, with highest levels in breast and lung cancers and lowest levels in renal cancers. These findings indicate that Survivin, which is commonly expressed in human tumor cell lines, can bind the effector cell death proteases caspase-3 and -7 in vitro and inhibits caspase activity and cell death in cells exposed to diverse apoptotic stimuli. Although quantitative differences may exist, these observations suggest commonality in the mechanisms used by IAP-family proteins to suppress apoptosis.  相似文献   
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