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991.
Rhodes grass ( Chloris gayana Kunth. cv. common) is a halophytic forage grass. Like most halophyles, its growth is positively affected by low levels of salinity but is inhibited by high salinity. However, such a definition is not clear and not unmistakable: NaCl concentrations which inhibit the growth of the whole plant stimulate the growth of single roots when applied to them individually.  相似文献   
992.
《Developmental cell》2023,58(7):597-615.e10
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993.
ObjectiveTo elaborate the significance of combined detection of cystatin C, urinary micro-albumin (mAlb) and β2-microglobulin (β2-MG) in diagnosis of the early renal injury in pregnancy-induced hypertension syndrome.MethodsA total of 120 patients with pregnancy-induced hypertension syndrome who were admitted to this hospital for treatment between November 2015 and October 2018 were enrolled as subjects, and divided into the control group (without complication of renal injury, n = 76) and the observation group (with complication of renal injury, n = 44) according to the complications of early renal injury. Furthermore, 60 patients who participated in the antenatal care in this hospital were enrolled as the normal subjects (normal group). Automatic biochemistry analyzer was utilized to measure CysC, urinary mAlb and β2-MG in serum to evaluate the specificity, sensitivity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of single or combined measurements of these indexes in diagnosis of the early renal injury in pregnancy-induced hypertension syndrome.ResultsIn the observation group, the levels of CysC, urinary mAlb and β2-MG were higher than those in the control group, while the levels in the normal group were the lowest (P < 0.05). Combined measurement of CysC, urinary mAlb and β2-MG showed a higher accuracy (90.0%) in diagnosis of the early renal injury in pregnancy-induced hypertension syndrome than the single measurements, and the difference had statistical significance (P < 0.05). Besides, the sensitivity, specificity, PPV and NPV of the combined measurements were 94.59%, 87.30%, 81.40% and 94.49%, slightly higher than the single measurements, with no statistical significance in differences (P > 0.05).ConclusionCysC, urinary mAlb and β2-MG can reflect the renal injury effectively, and the combined measurements shows potent accuracy in diagnosis of the early renal injury in pregnancy-induced hypertension syndrome, thereby providing the scientific evidence for early diagnosis and stipulation of rational therapeutic regimen and improving the pregnancy outcome.  相似文献   
994.
This study investigates morphological adaptations of rat extensor digitorum longus muscle to chronic low-frequency stimulation (10 Hz, 10 h/d, up to 61±7d). During the early stimulation period (2–4 d), increased basophilia and accumulation of RNA were seen predominantly in type-IIB fibers. Putative satellite cell activation, as indicated by 3H-thymidine incorporation, was also evident during this phase. By 12 d, fiber composition remained unaltered, but there was a decrease in the cross-sectional area of the type-IIB fibers. Following 28 d of low-frequency stimulation, the percentage of type-IIB fibers decreased from 43±3% to 0%, while type-IID fibers increased from 30±3% to 60±6%. The fraction of type-IIA fibers tended to increase (controls 19±3%; stimulated 29±4%), whereas that of the type-I fibers was unaltered (4±1%). At this time, the cross-sectional area of type-IID fibers was unaltered, but that of type-IIA and type-I fibers increased. Further stimulation resulted in a return of type-IID fibers to control levels (23±5%), and a marked increase in type-IIA fibers (45±8%). The percentage of type-I fibers increased from 4±1% to 8±1%. Throughout each stage of chronic stimulation, there was no histological evidence of fiber degeneration and regeneration. These results indicate that, in contrast to the rabbit, chronic low-frequency stimulation-induced fiber conversion in the rat extensor digitorum longus muscle is entirely due to fiber transformation.  相似文献   
995.
Abstract: Peroxisomal disorders are a newly described group of inherited neurological diseases. In disorders of peroxisomal biogenesis, e.g., Zellweger syndrome, owing to the lack of peroxisomes, catalase, a peroxisomal enzyme, is found to be present in the cytoplasm instead. We observed higher catalase activity (7.59 ± 0.41 mU/mg of protein) in cultured skin fibroblasts from Zellweger patients than in control fibroblasts (4.45 ± 0.29 mU/mg of protein). Moreover, we also found that the majority of the catalase in Zellweger cells was present in the inactive form. The specific activities following reactivation in Zellweger and control cells were 12.1 and 4.9 mU/mg of protein, respectively. To understand the molecular basis of higher levels of catalase in Zellweger than control cells, we examined the rate of synthesis and turnover of catalase and levels of catalase mRNA and protein levels in Zellweger cells as compared with control cells. The initial rates of synthesis of catalase in Zellweger (1.68 ± 0.15 mU/mg of protein) and control (1.51 ± 0.14 mU/mg of protein) cells were similar. The rates of turnover of catalase in Zellweger (t1/2 = 47 ± 8 h) and control (t1/2 = 49 ± 7 h) were also similar. Consistent with the enzyme activity, the levels of catalase protein were higher in Zellweger cells as compared with control cells. On the other hand, there was no difference in the level of catalase mRNA between control and Zellweger cells. Although the rate of synthesis in Zellweger and control cells were initially similar, it was down-regulated to a lower level at ~72 h of culture in control fibroblasts as compared with Zellweger cells, which continued to synthesize catalase at the same rate up to 5 days in culture. The presence of similar levels of mRNA in control and Zellweger cells and continued synthesis of catalase in Zellweger cells at a higher level as compared with control cells suggest a loss of regulation at the translational level.  相似文献   
996.
Abstract: A detailed analysis of the generation and subsequent metabolism of inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] following muscarinic cholinoceptor stimulation in primary cultures of rat cerebellar granule cells has been undertaken. Following incubation of cerebellar granule cell cultures with [3H]inositol for 48 h, labelling of the inositol phospholipid pool approached equilibrium. Significant basal labelling of inositol pentakisphosphate (InsP5) and inositol hexakisphosphate (InsP6), as well as inositol mono- to tetrakisphosphate, fractions was observed. Addition of carbachol (1 m M ) caused an immediate increase in level of Ins(1,4,5)P3 (peak increase two-fold over basal by 60 s), which was well-maintained over the initial 300 s following agonist addition. In contrast, only a modest, more slowly developing, increase in inositol tetrakisphosphate accumulation was observed, whereas labelling of InsP5 and InsP6 was entirely unaffected by carbachol stimulation. Analysis of the products of Ins(1,4,5)P3 and inositol 1,3,4,5-tetrakisphosphate metabolism in broken cell preparations strongly suggested that Ins(1,4,5)P3 metabolism occurs predominantly via the inositol polyphosphate 5-phosphatase route, with metabolism via the Ins(1,4,5)P3 3-kinase being a relatively minor pathway. In view of the pattern of inositol (poly)phosphate metabolites observed on stimulation of the muscarinic receptor, it seems likely that, over the time course studied, the inositol polyphosphates are derived principally from phosphoinositide-specific phospholipase C hydrolysis of phosphatidylinositol 4,5-bisphosphate, although some hydrolysis of phosphatidylinositol 4-phosphate cannot be excluded.  相似文献   
997.
Cognitive and speech development are delayed in children with Down syndrome (DS). We investigated the effect of dolphin-assisted therapy (DAT), a form of animal-assisted intervention, on the development of speech/language and social behavior in children with DS. We hypothesized that DAT would improve the social and cognitive functions with respect to verbalization and thereby promote task performance. A semi-crossover design was used to study 45 children with DS: 18 received a weekly one-hour session of DAT for 6 weeks (group A), 12 children (group B) started with swimming pool sessions (control period of 6 weeks) and thereafter received DAT, and 17 children (group C) were put on a waiting list (control period of 6 weeks) before receiving DAT. The parameters “verbalization,” “impulsiveness,” “proper understanding of rules,” “recognition of persons,” and “establishing contacts” were measured using the Matson Evaluation of Social Skills for Individuals with Severe Retardation (MESSIER) before and after DAT, as well as before and after each of the control periods. Repeated measures ANOVA revealed no significant changes for any of the variables during the control periods (swimming pool, waiting list). Following the period of DAT there was a significant improvement in “verbalization” and “recognition of persons,” while “impulsiveness” decreased. No significant changes were found for the other parameters. “Verbalization” continued to increase during the follow-up period of 6 months, while “recognition of persons” slightly decreased. The results of this study provide support for our hypothesis. Through improvements in verbalization and the recognition of persons, the execution of tasks among children with DS receiving DAT improved. Additional studies are needed to determine if these positive effects of DAT are long-term.  相似文献   
998.
扁桃体切除术是耳鼻咽喉科最常见的手术之一,临床上治疗由于扁桃体肥大所致的儿童睡眠阻塞性呼吸暂停综合征,最常用的手术方式为双侧扁桃体切除术。扁桃体在儿童生长发育过程中具有重要的免疫功能,完全切除扁桃体对儿童的免疫功能具有一定的影响。且扁桃体全部切除术后常见一些并发症如出血及疼痛,这使得许多学者提出了扁桃体部分切除术。扁桃体部分切除术较扁桃体全部切除术相比,手术时间短、术后并发症少,在缓解儿童阻塞症状的同时,保留了一部分扁桃体,对于免疫功能也有一定的保留。本文将从扁桃体部分切除术治疗儿童睡眠呼吸暂停综合征的临床疗效以及术后出血、术后疼痛方面作一综述,为扁桃体部分切除术应用于临床提供合理依据。  相似文献   
999.
PurposeTo observe the effect of cynomorium total flavone on the depression model of perimenopausal rat and to analyze the action characteristics of cynomorium total flavone on depression of rat with perimenopausal syndrome.MethodDuplicate the model of rat with perimenopausal depression based on the combined method of incomplete castration and chronic stimulation, and keep drug administration for 35d. And then measure related behavior indicators and the change of biochemical index level in serum and brains; measure the estrogen/androgen receptor (ER/AR) in related tissues and the ERmRNA expression in hypothalamus.ResultIt can be seen that cynomorium total flavone can significantly improve the behavior indicators of rat with perimenopausal depression; obviously or significantly change the level of related biomedical indexes in serum and brains of perimenopausal depressed rat; obviously or significantly increase the expression of ER/AR in related tissues of perimenopausal depressed rat; obviously or significantly increase the ERmRNA expression in hypothalamus.ConclusionCynomorium total flavone can adjust hypothalamic-pituitary-gonadal axis by increasing E2, and make related biomedical indexes and hormone receptors tend to be normal, so as to relieve perimenopausal syndrome and perimenopausal syndrome with depression.  相似文献   
1000.
The Smc5/6 complex facilitates chromosome replication and DNA break repair. Within this complex, a subcomplex composed of Nse1, Nse3 and Nse4 is thought to play multiple roles through DNA binding and regulating ATP-dependent activities of the complex. However, how the Nse1-Nse3-Nse4 subcomplex carries out these multiple functions remain unclear. To address this question, we determine the crystal structure of the Xenopus laevis Nse1-Nse3-Nse4 subcomplex at 1.7 Å resolution and examine how it interacts with DNA. Our structural analyses show that the Nse1-Nse3 dimer adopts a closed conformation and forms three interfaces with a segment of Nse4, forcing it into a Z-shaped conformation. The Nse1-Nse3-Nse4 structure provides an explanation for how the lung disease immunodeficiency and chromosome breakage syndrome-causing mutations could dislodge Nse4 from Nse1-Nse3. Our DNA binding and mutational analyses reveal that the N-terminal and the middle region of Nse4 contribute to DNA interaction and cell viability. Integrating our data with previous crosslink mass spectrometry data, we propose potential roles of the Nse1-Nse3-Nse4 complex in binding DNA within the Smc5/6 complex.  相似文献   
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