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991.
Stenosis of vessels proximal to the renal artery is an unusual cause of allograft ischemia. We report four patients who had such 'suprarenal' arterial stenoses leading to graft dysfunction that was reversed with revascularization. We additionally review the existing literature on this entity, outline the etiologies of such stenoses, as well as discuss the surgical and non-surgical therapeutic options in patients with this uncommon cause of allograft dysfunction.  相似文献   
992.
993.
Restless legs syndrome (RLS) and periodic limb movements in sleep (PLMS) are disorders that are common and disturbing to uremic patients. The treatment of these is problematic. Eight patients on chronic hemodialysis and continuous peritoneal dialysis completed a double-blind placebo-controlled crossover study using incremental doses of pergolide up to 0.25 mg at bedtime for treatment of RLS and sleep disruption. Five patients (62.5%) noted subjective improvement in restless legs symptoms and sleep quality. Objective results were improved only slightly by treatment. The percentage of the first hour in bed during which leg movements occurred decreased from 20.5 +/- 6.0 to 11.5 +/- 3.3, p < 0.05. However, findings during sleep were less positive. The following measures were not significant between placebo and treatment: leg movements per hour of sleep [53.7 +/- 22.3 vs 35.8 +/- 11.8 (p = 0.2)]; and percentage of sleep time spent with leg movements [5.5% +/- 3.2 vs 4.4% +/- 1.4 (p = 0.37)]. Patients continued to have very disrupted sleep, and we could not document an objective improvement in sleep architecture. Thus, although pergolide at the dose of 0.25 mg at bedtime provided subjective improvement in symptoms of restless legs and quality of sleep, and objectively decreased leg movements during the first hour in bed, objectively sleep continued to be disrupted. In this small patient group, the response to pergolide was not uniform, and further investigation is required to test effectiveness at higher doses.  相似文献   
994.
Infectious mononucleosis (IM) syndrome is typically caused by EBV, but also by drugs and other organisms such as CMV and HBV. It demonstrates a wide range of clinical and laboratory characteristics, presumably depending on the age of onset. However, associations of laboratory abnormalities with the clinical features have not been well documented. We evaluated here, the associations among patients with IM syndrome using of multiple regression (MR) and multiple logistic regression (MLR) analyses. We examined 90 (40 males, 50 females) patients, who were admitted to our hospital with IM syndrome. The diagnostic criteria were fever and presence of atypical lymphocytes (> 5% of the WBC or the count including monocytes > 5000/microliter), and at least 3 of 7 clinical features: tonsillitis, lymphadenopathy, skin rash, hepato-, spleno-megaly, hepatic dysfunction. The diagnosis of EBV was serologically confirmed in 41 cases. MR revealed that the higher age group tended to have lower platelet counts, and that lower platelet counts were associated with higher ALT levels. In addition, MLR revealed that patients with skin rash tended not to have splenomegaly. The frequency of splenomegaly was not related to age, contrary to the findings of previous reports. These findings are useful to differentiate IM syndrome based on laboratory data.  相似文献   
995.
The purpose of the study was to examine the effects of manipulating lung volume (LV) on phonatory and articulatory kinematic behavior during sentence production in healthy adults. Five men and five women repeated the sentence "I sell a sapapple again" under five LV conditions. These included (1) speaking normally, (2) speaking after exhaling most of the air from the lungs, (3) speaking at end expiratory level (EEL), (4) speaking after a maximal inhalation, and (5) speaking after a maximal inhalation while attempting to maintain as normal a mode of speech as possible. From a multichannel recording, measures were made of LV, sound pressure level (SPL), fundamental frequency (F0) and semitone standard deviation (STSD), and upper and lower lip displacements and peak velocities. When compared with the reference condition, the sentence was spoken significantly more quickly at the lowest LV. SPL increased significantly for the high LV condition, as did the women's F0 and STSD. Upper lip displacements and peak velocities generally decreased for LVs other than the reference condition. Lower lip movements showed inconsistent changes as a function of LV. Adjustments to the LV for speech led to SPL and F0 changes consistent with a coordinated control of the respiratory system and the larynx. However, less consistent effects were observed in the articulatory kinematic measures, possibly because of a less direct biomechanical and neural control linkage between respiratory and articulatory structures.  相似文献   
996.
Analysis of transgenic mice expressing familial amyotrophic lateral sclerosis (ALS)-linked mutations in the enzyme superoxide dismutase (SOD1) have shown that motor neuron death arises from a mutant-mediated toxic property or properties. In testing the disease mechanism, both elimination and elevation of wild-type SOD1 were found to have no effect on mutant-mediated disease, which demonstrates that the use of SOD mimetics is unlikely to be an effective therapy and raises the question of whether toxicity arises from superoxide-mediated oxidative stress. Aggregates containing SOD1 were common to disease caused by different mutants, implying that coaggregation of an unidentified essential component or components or aberrant catalysis by misfolded mutants underlies a portion of mutant-mediated toxicity.  相似文献   
997.
The present study demonstrates 1alpha,25-dehydroxyvitamin D3 (1alpha-25-(OH)2D3) synergism toward transforming growth factor (TGF)-beta1-induced activation protein-1 (AP-1) activity in mouse osteoblastic MC3T3-E1 cells via the nuclear receptor of the vitamin. 1alpha-25-(OH)2D3 synergistically stimulated TGF-beta1-induced expression of the c-jun gene in the cells but not that of the c-fos gene. We actually showed by a gel mobility shift assay 1alpha-25-(OH)2D3 synergism of TGF-beta1-induced AP-1 binding to the 12-(O-tetradecanoylphorbol-13-acetate response element (TRE). 1alpha-25-(OH)2D3 markedly stimulated the transient activity of TGF-beta1-induced AP-1 in the cells transfected with a TRE-chloramphenicol acetyltransferase (CAT) reporter gene. Also, a synergistic increase in TGF-beta1-induced CAT activity was observed in the cells cotransfected with an expression vector encoding vitamin D3 receptor (VDR) and the reporter gene. However, the synergistic CAT activity was inhibited by pretreatment with VDR antisense oligonucleotides. In addition, in a Northern blot assay, we observed 1alpha-25-(OH)2D3 synergism of TGF-beta1-induced expression of the c-jun gene in the cells transfected with the VDR expression vector and also found that the synergistic action was clearly blocked by VDR antisense oligonucleotide pretreatment. The present study strongly suggests a novel positive regulation by 1alpha-25-(OH)2D3 of TGF-beta1-induced AP-1 activity in osteoblasts via "genomic action."  相似文献   
998.
OBJECTIVE: To determine the utility of CT-determined main pulmonary artery diameter (MPAD) for predicting pulmonary hypertension (PH) in patients with parenchymal lung disease. DESIGN: Retrospective review of right-heart hemodynamic data and chest CT scans in 45 patients. SETTING: Tertiary-referral teaching hospital and VA hospital. PATIENTS: Between October 1990 and December 1995, 36 patients referred for evaluation of parenchymal lung disease or possible pulmonary vascular disease were found to have PH, as defined by mean pulmonary artery pressure (mPAP) > or =20 mm Hg. Nine control patients (mPAP <20 mm Hg) were also identified (4 from hospital records search, 5 after evaluation for possible PH). RESULTS: CT-determined MPAD was 35+/-6 mm in patients with PH and 27+/-2 mm in control subjects. In our group of patients, MPAD > or =29 mm had a sensitivity of 87%, specificity of 89%, positive predictive value (PPV) of 0.97, and positive likelihood ratio (LR) of 7.91 for predicting PH; in the subgroup of patients with parenchymal lung disease (n=28, PH and control subjects), MPAD > or =29 mm had a sensitivity of 84%, specificity of 75%, PPV of 0.95, and positive LR of 3.36 for predicting PH. The most specific findings for the presence of PH were both MPAD > or =29 mm and segmental artery-to-bronchus ratio > 1:1 in three or four lobes (specificity, 100%). There was no linear correlation between the degree of PH and MPAD (r=0.124). CONCLUSIONS: CT-determined MPAD has excellent diagnostic value for detection of PH in patients with advanced lung disease. Therefore, standard chest CT scans can be used to screen for PH as a cause of exertional limitation in patients with parenchymal lung disease. Because CT is commonly used to evaluate parenchymal lung disease, this information is readily available.  相似文献   
999.
In this study, we examined the ability of tumour necrosis factor-alpha (TNF) to stimulate the mitogen-activated protein (MAP) kinase homologues p42/44 MAP kinase, c-Jun NH2-terminal kinase (JNK) and p38 MAP kinase and its effect upon DNA synthesis in primary cultures of bovine aortic endothelial cells (BAECs). TNF strongly stimulated p38 MAP kinase and JNK activity in both a time- and concentration-dependent manner. By contrast, TNF was a very poor activator of p42/44 MAP kinase relative to the known activator of p42/44 MAP kinase in endothelial cells, adenosine triphosphate (ATP). TNF-stimulated activation of p38 MAP kinase, and MAPKAP kinase-2, a known downstream target of p38 MAP kinase, was strongly inhibited by pre-incubation with the p38 MAP kinase inhibitor SB203580, whereas the minor activation of p42/44 MAP kinase was abolished by pre-incubation of the cell with the novel MAP kinase kinase 1 inhibitor PD098059. Addition of TNF resulted in a 50-60% decrease in DNA synthesis in BAECs. Pre-incubation with PD098059 or co-incubation with ATP failed to modify the inhibitory effect of TNF upon DNA synthesis. SB203580 reduced basal DNA synthesis by approximately 50%; however, if failed to modify the inhibition mediated by TNF. These results indicate that TNF strongly activates both p38 MAP kinase, JNK and, to a minor extent, p42/p44 MAP kinase. It is likely that only one of these kinases, JNK, plays a role in the regulation of DNA synthesis in these cells.  相似文献   
1000.
Rat inner medullary collecting ducts (IMCD3s) possess a luminal Na+-dependent, active urea secretory transport process, which is upregulated by water diuresis. In this study of perfused IMCDs microdissected from base (IMCD1), middle (IMCD2), or tip (IMCD3) of the inner medulla, we tested whether furosemide diuresis alters active urea transport. Rats received furosemide (10 mg/d s.c. for 3-4 d) and were compared with pair-fed control rats. Furosemide significantly decreased urine osmolality and urea clearance, and increased blood urea nitrogen. IMCD3s from furosemide-treated rats had significantly lower rates of active urea secretion than IMCD3s from control rats. IMCD2s showed no active urea transport in control or furosemide-treated rats. IMCD1s from control rats had no active urea transport, but IMCD1s from furosemide-treated rats expressed significant rates of active urea reabsorption. In IMCD1s, this active urea reabsorptive transport process was inhibited by: (i) 0. 25 mM phloretin (bath); (ii) 1 mM ouabain (bath); and (iii) replacing bath Na+ with NMDG+; it was stimulated by 10 nM bumetanide (bath). In summary, we found that furosemide decreased active urea secretion in IMCD3s and induced active urea reabsorption in IMCD1s. The new Na+- dependent, active urea reabsorptive transport process may be a basolateral Na+-urea antiporter.  相似文献   
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