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141.
142.
After birth, the hematopoietic system develops along with bone formation in mammals. Osteolineage cells are derived from mesenchymal progenitor cells, and differentiate into several types of bone-forming cells. Of the various types of cell constituents in bone marrow, osteolineage cells have been shown to play important roles in hematopoiesis. Early studies have identified osteoblasts as a hematopoietic stem cell niche component. Since that time, the role of endosteal microenvironment as a critical regulator of hematopoietic stem/progenitor cell (HSC/HPC) behavior has been appreciated particularly under stress conditions, such as cytokine-induced HSC/HPC mobilization, homing/engraftment after bone marrow transplantation, and disease models of leukemia/myelodysplasia. Recent studies revealed that the most differentiated osteolineage cells, i.e., osteocytes, play important roles in the regulation of hematopoiesis. In this review, we provide an overview of recent advances in knowledge of regulatory hematopoietic mechanisms in the endosteal area.  相似文献   
143.
Cognitive Therapy and Research - Increased overgeneral categoric memory has been reported in individuals with dysphoria and a history of depression. In three experiments, we examined whether...  相似文献   
144.

Object

The purpose of this study is to evaluate the outcome of our therapeutic strategy for antenatally diagnosed congenital diaphragmatic hernia (ADCDH).

Methods

We treated 61 cases of ADCDH according to our strategy. Prostaglandin E1 was required to be maintained the patency of the ductus arteriosus (PDA) in 39 cases (Group I) while it was not administered in 22 cases (Group II). Left ventricular end-diastolic dimension (LVDD) and Tei index were measured with echocardiography on days 0, 2, and 7 after birth. Radical surgery was performed on all cases by day 2.

Results

On day 0, Group I showed smaller LVDD and Tei index than those in Group II. Between day 0 and day 2, these parameters increased significantly in Group I, but not in Group II. On day 7, no significant difference in these parameters was observed between the two groups. Five patients died of cardiac and respiratory failure, resulting in a survival rate of 92 %.

Conclusion

Our therapeutic strategy improves the clinical outcome of ADCDH. This can be attributed to two factors: earlier surgery resulting in improved LV function. The latter attenuates pulmonary hypertension and maintains PDA with a consequent decrease in right ventricular afterload to compensate for the low cardiac output resulting from PDA.  相似文献   
145.
Neonatal estrogen treatment (NET) induces morphological changes in male reproductive organs. NET with β-estradiol 17-cypionate is reported to induce inflammation with stromal-epithelial abnormalities in the prostate and seminal vesicles in post-pubertal mice. The aim of this study was to investigate the histopathology of the testis, ductuli efferentes, epididymis, and vas deferens in mice after NET with β-estradiol 17-cypionate. No morphological changes in these organs were observed until 4 weeks after NET. However, some inflammatory cells were found in epididymis and vas deferens 6 weeks after NET. Eight weeks after NET, inflammatory cells spread to the ductuli efferentes and inflammation was severe from 6 to 12 weeks after NET. Inflammatory cells were never seen in the whole testis, but cystic dilatation of the rete testes with spermatogenic disturbance was found around the mediastinum testis. Many inflammatory cells emigrated into the lumen of the epididymis, resulting in complete absence of spermatozoa in the vas deferens. Most of the inflammatory cells penetrating into the epithelial layers of epididymal ducts were neutrophils. These results indicate that in post-pubertal mice, NET with β-estradiol 17-cypionate induces inflammation in the ductuli efferentes, epididymis, and vas deferens, but not in the testis, provoking obstructive azoospermia.  相似文献   
146.
The vesicular glutamate transporters, VGLUT1 and VGLUT2, reportedly display complementary distribution in the rat brain. However, co-expression of them in single neurons has been reported in some brain areas. We previously found co-expression of VGLUT1 and VGLUT2 mRNAs in a number of single neurons in the principal sensory trigeminal nucleus (Vp) of the adult rat; the majority of these neurons sent their axons to the thalamic regions around the posteromedial ventral nucleus (VPM) and the posterior nuclei (Po). It is well known that trigeminothalamic (T-T) projection fibers arise not only from the Vp but also from the spinal trigeminal nucleus (Vsp), and that trigeminocerebellar (T-C) projection fibers take their origins from both of the Vp and Vsp. Thus, in the present study, we examined the expression of VGLUT1 and VGLUT2 in Vp and Vsp neurons that sent their axons to the VPM/Po regions or the cortical regions of the cerebellum. For this purpose, we combined fluorescence in situ hybridization (FISH) histochemistry with retrograde tract-tracing; immunofluorescence histochemistry was also combined with anterograde tract-tracing. The results indicate that glutamatergic Vsp neurons sending their axons to the cerebellar cortical regions mainly express VGLUT1, whereas glutamatergic Vsp neurons sending their axons to the thalamic regions express VGLUT2. The present data, in combination with those of our previous study, indicate that glutamatergic Vp neurons projecting to the cerebellar cortical regions express mainly VGLUT1, whereas the majority of glutamatergic Vp neurons projecting to the thalamus co-express VGLUT1 and VGLUT2.  相似文献   
147.
Nitrogen/phosphorus-containing melamines (NPCM), a durable flame-retardant, were prepared by the successive treatment of ArOH (Ar = BrnC6H5−n, n = 0, 1, 2, and 3) with POCl3 and melamine monomer. The prepared flame-retardants were grafted through the CH2 unit to lignocellulose nanofibers (LCNFs) by the Mannich reaction. The resulting three-component products were characterized using FT-IR (ATR) and EA. The thermal behavior of the NPCM-treated LCNF fabric samples was determined using TGA and DSC analyses, and their flammability resistances were evaluated by measuring their Limited Oxygen Index (LOI) and the UL-94V test. A multitude of flame retardant elements in the fabric samples increased the LOI values as much as 45 from 20 of the untreated LCNFs. Moreover, the morphology of both the NPCM-treated LCNFs and their burnt fabrics was studied with a scanning electron microscope (SEM). The heat release lowering effect of the LCNF fabric against the water-based paint was observed with a cone calorimeter. Furthermore, the mechanical properties represented as the tensile strength of the NPCM-treated LCNF fabrics revealed that the increase of the NPCM content in the PP-composites led to an increased bending strength with enhancing the flame-retardance.

LCNFs were grafted with nitrogen/phosphorus-containing melamines to achieve potent flame-retardance and converted to PP-composites of improved mechanical properties.  相似文献   
148.
The purposes of this meta-analysis were (1) to examine the associations between work engagement (WE) and the personality dimensions of five-factor model and (2) to determine how much variance in WE is explained by these five factors. We performed a database search for studies related to personality traits and WE, and 36 papers that reported correlation coefficients were selected for the meta-analysis. After correcting for publication bias using the trim-and-fill method, conscientiousness had the strongest association with WE (ρ=0.41), followed by extraversion and openness to experience (0.38), neuroticism (−0.36), and agreeableness (0.27). Moreover, 30% of the WE variance could be explained by the five-factor model (R2=0.33, 95%CI=0.26–0.49) according to a path analysis using the weighted average correlation for unreliability. This proportion was higher than that from a previous meta-analysis of job satisfaction and job performance and was lower than that of personality and WE. Thus, to enhance WE, it is necessary to evaluate both the personality and the psychosocial work environment in detail.  相似文献   
149.
Central distribution of afferent and efferent components of the pudendal nerve was examined in the cat by the HRP method after applying HRP to the central cut end of the pudendal nerve. Retrogradely labeled neuronal cell bodies were located primarily in the feline homologue of the Onuf's X nucleus, constituting a slender longitudinal cell column in the ventral horn of the S1 and S2 cord segments. The Onuf's nucleus was present constantly from middle S1 to high S2 cord segments, and occasionally extended rostrally to high S1 or low L7, and caudally to middle S2, low S2, or high S3 cord segments. No sex differences were observed in the distribution pattern, number, and soma size of labeled neurons in the Onuf's nucleus. Transganglionically labeled dorsal root fibers were found to terminate ipsilaterally in the lamina I of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments and the gracile nucleus, and bilaterally with an ipsilateral predominance in the dorsal commissural gray and laminae III, IV, V, and VI of the dorsal horn at levels of lower lumbar, sacral, and higher coccygeal cord segments. Some labeled dorsal root fibers appeared to end ipsilaterally in the regions where the sacral parasympathetic preganglionic neurons have been shown to be located.  相似文献   
150.
Troglitazone, a thiazolizidinedione, has recently been reported to possess anti-arteriosclerotic properties. To evaluate mechanisms underlying the anti-arteriosclerotic effects of troglitazone, we examined the effect of troglitazone on growth, expression of growth factors, and insulin signaling in vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) which produce angiotensin II (Ang II) in a homogeneous culture. Troglitazone inhibited basal and serum-stimulated DNA synthesis and inhibited increases in the number of VSMC from SHR and normotensive Wistar-Kyoto (WKY) rats. Its inhibition was greater in VSMC from SHR. Troglitazone abolished DNA synthesis in response to Ang II in VSMC from both rat strains and markedly inhibited DNA synthesis in response to epidermal growth factor (EGF) and platelet-derived growth factor (PDGF)-AA in VSMC from SHR. Troglitazone did not alter the expression of transforming growth factor (TGF)-beta1, PDGF A-chain, or basic fibroblast growth factor (bFGF) mRNAs in VSMC from WKY rats, but it markedly decreased expression of these growth factor mRNAs in VSMC from SHR. Troglitazone markedly decreased basal and Ang II-stimulated expression of extracellular signal-regulated kinase proteins in VSMC from both rat strains. Troglitazone abolished Ang II-induced suppression of phosphatidilinositol 3-kinase (PI3-kinase) activity, insulin receptor substrate-1 (IRS-1) associated tyrosine phosphorylation, and IRS-1 associated p85 levels in VSMC from WKY rats. Basal PI3-kinase activity, tyrosine phosphorylation of IRS-1, and IRS-1 associated p85 levels were lower in VSMC from SHR than in cells from WKY rats. Troglitazone significantly increased PI3-kinase activity, IRS-1 associated tyrosine phosphorylation, and IRS-1 associated p85 levels in VSMC from SHR. These results indicate that troglitazone produce its anti-arteriosclerotic effects through suppression of the action of growth-promoting factors including Ang II, and that troglitazone inhibits Ang II-induced suppression of insulin signaling in VSMC from SHR, suggesting that tissue Ang II may lead to insulin resistance and to arteriosclerosis in hypertension. Troglitazone may be useful in the treatment of insulin resistance as well as of hypertensive vascular diseases.  相似文献   
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