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41.
Porter  CD; Parkar  MH; Levinsky  RJ; Collins  MK; Kinnon  C 《Blood》1993,82(7):2196-2202
Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease.  相似文献   
42.
Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) clearly hastens myeloid recovery in patients with relapsed hematologic malignancies undergoing autologous bone marrow transplantation (ABMT). In efforts to further improve neutrophil engraftment and shorten hospital stay in ABMT patients, rhGM-CSF was administered by a potentially more potent route (continuous infusion) to non-Hodgkin's lymphoma (NHL) patients with better BM reserve (first remission). Time to myeloid engraftment was compared with that of NHL patients treated in first remission at our institution on a similar ABMT protocol but without growth factor support (controls). Median neutrophil engraftment (absolute neutrophil count, 500 cells/microL) in first remission patients treated with rhGM-CSF was 14 days, compared with 22 days in controls (P = .0001). Hospital stays were also significantly reduced for rhGM-CSF patients (P = .0003). Platelet engraftment did not differ between the two groups. Persistent fever and generalized serositis were the primary toxicities. rhGM-CSF, delivered by this route, was efficacious but more toxic than 2-hour rhGM-CSF infusions previously reported by other investigators. Future alterations in both dose and schedule may retain comparable efficacy yet diminish toxicity.  相似文献   
43.
INTRODUCTION AND OBJECTIVES: The importance of the clinical presentation in the frequency and type of recurrences of ventricular arrhythmias in patients that received an automatic implantable defibrillator is not well known. The purpose of this study was to analyze the frequency and type of recurrences in patients with an old myocardial infarction that received an automatic implantable defibrillator with electrogram recording. METHODS AND RESULTS: We analyzed 100 patients classified in 3 groups according to their clinical presentation: Sustained Monomorphic Ventricular Tachycardia (VT Group n = 65), Cardiac Arrest (CA Group = 19), and Syncope (Syncope Group n = 16). There were no significant differences in the clinical variables among the different groups, nor in the inducibility of arrhythmia at the electrophysiologic study. In a follow-up 27 +/- 14 months, 54% of patients presented at last one episode of sustained ventricular arrhythmia. All recurrences except one were as sustained monomorphic ventricular tachycardia (776 episodes). 81% of episodes of sustained monomorphic ventricular tachycardia (630) were treated with antitachycardia pacing with an effectiveness of 89%. There were no differences in the probability of arrhythmic recurrence among groups but death probability was higher in the ventricular fibrillation group at 36 follow-up months (38% vs 7% and 12% in the sustained monomorphic ventricular tachycardia and syncope groups respectively, p = 0.0113). CONCLUSIONS: In the patients with an old myocardial infarction and malignant ventricular arrhythmias, most of recurrences are due to sustained monomorphic ventricular tachycardia independently of the clinical presentation. The antitachycardia pacing is not only effective in patients with documented sustained monomorphic ventricular tachycardia but also in those that are presented as cardiac arrest or syncope.  相似文献   
44.
The grey zone (GZ; 45–54 CGG repeats in the FMR1 gene) is considered a normal allele; however, several studies have found a high frequency of GZ in movement disordered populations. Here, we describe neurological features of fragile X‐associated tremor/ataxia syndrome (FXTAS) in two carriers of GZ alleles, although FXTAS has been defined as occurring only in premutation carriers (55–200 CGG repeats). Both patients had family members who had premutation and were diagnosed with FXTAS. The presence of relatively high GZ alleles with elevated fragile X mental retardation 1 mRNA (FMR1‐mRNA) combined with a family history of FXTAS that may represent a facilitating genetic background for FXTAS are the factors that led to the presence of FXTAS in these individuals with a GZ allele. Further research into clinical involvement of GZ alleles is recommended and the definition of FXTAS may require revision.  相似文献   
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46.
The family climate has notable impact on cognitive, emotional, behavioural, social and physical development of children and adolescents and can be influenced by parents' health status. The present study aimed at evaluating whether living with a parent with alcohol use disorder negatively influences the perceived emotional family climate, parental attitudes and internal representations of family relationships. Forty-five children living with a parent with alcohol use disorder and 45 controls, matched for sex and age, completed the Level of Expressed Emotion Scale and the Family Attitudes Questionnaire. Their significant parent completed the Parental Attitudes Scale. The results suggested that living with a parent with an alcohol use disorder increased the risk of having perceived higher levels of emotional response, attitude towards illness and expectations from their parents; it also increased the probability of being exposed to lower parental pleasure and of having represented worse family relationships. Emotion regulation interventions might be useful to protect children living with a parent with alcohol use disorder from a potential chaotic and unpredictable family environment.  相似文献   
47.
BACKGROUND AND PURPOSE:Brain white matter is frequently affected in mitochondrial diseases; optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy are the most frequent mitochondrial monosymptomatic optic neuropathies. In this observational study, brain white matter microstructure was characterized by DTI in patients with optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy, in relation to clinical and genetic features.MATERIALS AND METHODS:Nineteen patients with optic atrophy gene 1-autosomal dominant optic atrophy and 17 with Leber hereditary optic neuropathy older than 18 years of age, all genetically diagnosed, and 19 healthy volunteers underwent DTI by using a 1.5T MR imaging scanner and neurologic and ophthalmologic assessments. Brain white matter DTI metrics were calculated for all participants, and, in patients, their correlations with genetics and clinical findings were calculated.RESULTS:Compared with controls, patients with optic atrophy gene 1-autosomal dominant optic atrophy had an increased mean diffusivity in 29.2% of voxels analyzed within major white matter tracts distributed throughout the brain, while fractional anisotropy was reduced in 30.3% of voxels. For patients with Leber hereditary optic neuropathy, the proportion of altered voxels was only 0.5% and 5.5%, respectively, of which half was found within the optic radiation and 3.5%, in the smaller acoustic radiation. In almost all regions, fractional anisotropy diminished with age in patients with optic atrophy gene 1-autosomal dominant optic atrophy and correlated with average retinal nerve fiber layer thickness in several areas. Mean diffusivity increased in those with a missense mutation. Patients with Leber hereditary optic neuropathy taking idebenone had slightly milder changes.CONCLUSIONS:Patients with Leber hereditary optic neuropathy had preferential involvement of the optic and acoustic radiations, consistent with trans-synaptic degeneration, whereas patients with optic atrophy gene 1-autosomal dominant optic atrophy presented with widespread involvement suggestive of a multisystemic, possibly a congenital/developmental, disorder. White matter changes in Leber hereditary optic neuropathy and optic atrophy gene 1-autosomal dominant optic atrophy may be exploitable as biomarkers.

Mutations in optic atrophy gene 1 are the main cause of autosomal dominant optic atrophy (DOA) (Online Mendelian Inheritance in Man 605290).1,2 DOA is characterized clinically by insidiously progressive visual loss in childhood, centrocecal scotoma, dyschromatopsia, and temporal or diffuse pallor of the optic discs, due to selective loss of retinal ganglion cells leading to atrophy of the optic nerve.1,2 Similarly, Leber hereditary optic neuropathy (LHON) (Online Mendelian Inheritance in Man 535000) is characterized by subacute loss of central vision, dyschromatopsia, and optic atrophy due to maternally inherited point mutations in mitochondrial DNA that affect respiratory complex I.1,2DOA and LHON represent the so-called nonsyndromic mitochondrial optic neuropathies, characterized by optic nerve atrophy as the only or at least prevalent pathologic feature with an early and preferential involvement of the small fibers in the papillomacular bundle.3,4 Recent MR imaging studies by using voxel-based morphometry,5 DWI,6 and DTI7 have also indicated abnormalities of the optic radiation in patients with LHON, confirmed by postmortem investigation,6 suggesting a trans-synaptic degeneration. A similar secondary involvement of the retrogeniculate visual pathway could also be hypothesized in patients with DOA. Furthermore, given that the optic atrophy gene 1 (OPA1) is highly expressed in the retina but also in the brain1,2,8 and that a subgroup of patients with specific OPA1 mutations have a multisystem neurologic disorder,9 it is reasonable to also hypothesize a subclinical extravisual brain involvement in patients with OPA1-DOA.The aim of the present study was to investigate the brain white matter of patients with OPA1-DOA compared with those with LHON and healthy controls, by using a voxelwise analysis of DTI, which can disclose abnormal water diffusivity in brain areas where atrophy and/or gliosis occur,10 to look for subtle structural alterations.  相似文献   
48.
49.
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD.  相似文献   
50.
Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.  相似文献   
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