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Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment.  相似文献   
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BACKGROUND AND OBJECTIVES: Myofascial pain is the leading cause of chronic low back pain and in most cases can be successfully resolved with trigger point injections of local anesthetics. This type of pain can exist during pregnancy and exceed the analgesia provided by an epidural for labor. METHODS: A 31-year-old primiparous woman received an epidural infusion for labor analgesia. Despite complete resolution of labor pain and a solid, bilateral T10 block, the patient reported discomfort at two discrete locations in her right lumbar paraspinous muscle. RESULTS: The administration of local anesthetic via trigger point injections resulted in successful palliation of the myofascial pain. CONCLUSIONS: Myofascial pain can be an etiology of back pain in the parturient. Trigger point injections, even when used concomitantly with a functioning epidural infusion, can be a valuable aid for the provision of complete analgesia.  相似文献   
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The formation of factor VIII antibodies is a major problem for replacement therapy of haemophilia A patients. Antibodies occur in 5-30% of patients with severe haemophilia A. The reason for antibody formation is still unknown. In this study we correlate for the first time different factor VIII gene mutations, stop- and missense mutations, large and small deletions and intrachromosomal intron 22 recombinations to antibody formation. A total of 364 patients with known inhibitor status of our institute, of the database, and of 3 studies representing intron-22-inversion data are included. The results show that the risk for developing factor VIII antibodies is strongly related to stop mutations. large deletions and intrachromosomal recombinations. A probable explanation could be the complete lack of endogenous circulating factor VIII protein in these cases. Other factors that might be important for the pathogenesis of inhibitor formation, e. g. the antenatal period, as well as possible therapeutic effects, are discussed.  相似文献   
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The aim of the study was to test the hypothesis that magnetic resonance (MR) imaging-guided and -monitored noninvasive ultrasonic surgery can be performed in highly perfused tissues from outside the body. A simulation study was performed to evaluate the optimal sonication parameters. An MR-compatible positioning device was then used to manipulate a focused ultrasound transducer in an MR imager, which was used to sonicate kidneys of five rabbits at various power levels and different durations. Temperature elevation during sonication was monitored with a T1-weighted spoiled gradient-echo sequence. The simulation study demonstrated that a sharply focused transducer and relatively short sonication times (30 seconds or less) are necessary to prevent damage to the overlying skin and muscle tissue, which have a much lower blood perfusion rate than kidney. The experiments showed that the imaging sequence was sensitive enough to show temperature elevation during sonication, thereby indicating the location of the beam focus. Histologic evaluations showed that kidney necrosis could be consistently induced without damage to overlying skin and muscle. The study demonstrated that highly perfused tissues such as the renal cortex can be coagulated from outside the body with focused ultrasound and that MR imaging can be used to guide and monitor this surgery.  相似文献   
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We report the results of a multicentre, double-blind, placebo-controlled study of topical therapy with omega-3-polyunsaturated fatty acids (omega-3-PUFA) in 52 patients suffering from moderate plaque-type psoriasis. In each patient, two similar stable psoriatic plaques served as indicator lesions for the study. One indicator lesion was randomly assigned to treatment with topical preparations of highly purified omega-3-PUFA in one of two concentrations (1 or 10%), and the other was treated with placebo. Efficacy assessment was based on changes in local psoriasis severity index, area involved, erythema, desquamation, induration and pruritus. After 8 weeks of treatment, all indicator lesions had improved significantly, compared with baseline. However, no statistically or clinically relevant differences between the omega-3-PUFA-treated and the placebo-treated lesions were found. Therapy was well tolerated and, apart from one patient who developed perilesional eczema, no clinically relevant adverse events occurred. In conclusion, topical omega-3-PUFA were not effective in a randomized, placebo-controlled, double-blind setting. Results of non-blind trials should be (re-)considered with caution.  相似文献   
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We have used the fluorescence in situ hybridization (FISH) technique to refine the localization of the cystic fibrosis transmembrane conductance regulator (CFTR) gene on human chromosome 7. The result shows that the gene is most likely located within band q31.3.  相似文献   
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Fragments of 32, 26 and 17 kDa of the porcine estradiol receptor were prepared, all of which contain the ligand-binding site. While dimers of the 32 and 26 kDa fragments like those of intact receptor can be dissociated by protonation, the dimer of the 17 kDa fragment obtained by trypsination of the 26 kDa fragment is resistant to lowering the pH from 7.0 to 6.5 and below. Its dissociation can be achieved by 0.5 M MgCl2 at pH 7.0. All fragments are recognized by the MAB 13H2 in Western blots. The antibody also reacts with native receptor and the three fragments, both in their monomer and dimer states. The combining ratios of antibody with receptor, or its fragments, in the monomer and dimer states and the weakening of the estradiol-receptor bond by antibody attachment support the back to back and head to toe model of receptor dimers.  相似文献   
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