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11.
Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) are currently used alone or in combination for therapeutic applications especially for bone repair. We tested whether MSCs can be isolated from bone marrow (BM) aspirate using a commercially available kit commonly used to obtain PRP from peripheral blood (PB). Results revealed that mononuclear cells and platelets from both PB and BM could be efficiently isolated by obtaining a mononuclear and platelet rich fraction (PB‐MPRF and BM‐MPRF, respectively). Starting with comparable volumes, the number of platelets increased 1.5‐fold in BM‐MPRF compared to PB‐MPRF. The number of clonogenic cells in BM‐MPRF samples was significantly higher than whole BM samples as revealed by CFU‐F assay (54.92 ± 8.55 CFU‐F/1.5 x 105 nucleated cells and 32.50 ± 12.43 CFU‐F/1.5 x 105 nucleated cells, respectively). Cells isolated from BM‐MPRF after in vitro expansion fulfilled the definition of MSCs by phenotypic criteria, and differentiated along osteogenic, adipogenic and chondrogenic lineages following induction. Results showed that the kit isolated MSCs and platelets from BM aspirate. Isolated MSCs were further expanded in a laboratory and BM‐MPRF was used clinically following BM withdrawal for rapid intra‐operative cell therapy for the treatment of bone defects. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
12.
Stem cell transplantation for hemoglobinopathies   总被引:4,自引:0,他引:4  
Hereditary anemias caused by beta-thalassemia and sickle cell disease are the most common genetic diseases worldwide. Supportive therapies such as chronic lifelong transfusions, iron chelation for thalassemia, and transfusions or hydroxyurea for sickle cell anemia have significantly ameliorated clinical manifestations of these diseases but cannot eliminate disease and treatment-related complications that result in end-organ damage. Allogeneic hematopoietic stem cell transplantation is the only cure for patients with hemoglobinopathies. Results of transplants have steadily improved over the last few decades due to effective control of transplant-related complications and development of new preparative regimens. Our understandings of mixed chimerism in patients with hemoglobinopathies provide a rationale for the use of less intensive conditioning regimens and gene therapy in these disorders. Although the role of stem cell transplantation for thalassemia major is well defined, few transplants have been carried out in sickle cell disease, and, in light of recent advances, the role of stem cell transplantation in this disease should be revised. This review summarizes the current status of stem cell transplantation for hemoglobinopathies.  相似文献   
13.
Individuals with Down's syndrome (DS), i.e., trisomy 21, over 40 years of age, are likely to develop neuropathological changes characteristic of Alzheimer's disease (AD). The involvement of chromosome 21 both in DS and AD suggests a shared genetic susceptibility to these disorders, but genetic determinants are still undefined. The -48C/T polymorphism in the PSEN1 promoter is a possible candidate, since it has recently been associated with an increased risk of early onset AD. Based on the assumption that the excess of dementia in DS might be a consequence of a different distribution of the -48C/T polymorphism, we investigated the association between DS and this polymorphism in patients with trisomy 21 and controls. Overall, 260 DS patients and 197 controls were recruited at the Department of Neurosciences, Tor Vergata University of Rome. Cases and controls had similar age and gender distribution. High molecular weight DNA was extracted from whole blood samples collected in EDTANa(2) and -48C/T genotypes were determined. Genotype and allele frequencies were compared between cases and controls. Cases were less likely than controls to have the CC genotype ( P = 0.05). A significant difference for allele distribution between DS cases and controls was found, with DS showing a lower frequency of the allele C compared with the control population (OR: 0.57; 95% CI: 0.35-0.91; P = 0.01). No significant interaction of PSEN1 with age, gender, ApoE and -850 TNF-alpha polymorphisms was found. The association found suggests that the -48C/T polymorphism in the PSN1 gene promoter, which is involved in the modulation of amyloid beta load in human AD, is associated with DS. However, the biological role of this polymorphism in DS-related dementia remains unclear and merits further investigation.  相似文献   
14.
Allogeneic hematopoietic stem cell transplantation (HSCT) has been a curative therapeutic option for a wide range of immune hematologic malignant and non-malignant disorders including genetic diseases and inborn errors. Once in the host, allogeneic transplanted cells have not only to ensure myeloid repopulation and immunological reconstitution but also to acquire tolerance to host human leukocyte antigens via central or peripheral mechanisms. Peripheral tolerance after allogeneic HSCT depends on several regulatory mechanisms aimed at blocking alloimmune reactivity while preserving immune responses to pathogens and tumor antigens. Patients transplanted with HSCT represent an ideal model system in humans to identify and characterize the key cellular and molecular players underlying these mechanisms. The knowledge gained from these studies has allowed the development of novel therapeutic strategies aimed at inducing long-term peripheral tolerance, which can be applicable not only in allogeneic HSCT but also in autoimmune diseases and solid-organ transplantation. In the present review, we describe Type 1 regulatory T cells, initially discovered and characterized in chimeric patients transplanted with human leukocyte antigen-mismatched HSCT, and how their presence correlates to tolerance induction and maintenance. Furthermore, we summarize different cell therapy approaches with regulatory T cells, designed to facilitate tolerance induction, minimizing pharmaceutical interventions.  相似文献   
15.
We report the incidence of cytomegalovirus (CMV) seroconversion, infections and mortality in 169 consecutive thalassemic patients transplanted in Pesaro. We observed a 44% incidence of early seroconversion and a 52% incidence of late seroconversion. No relationship was found between seroconversion and acute or chronic graft-versus-host disease (GVHD) or rejection. The donor status did not influence the incidence of seroconversion, GVHD and rejection. Only three patients died of CMV infection (1.7%); in each case CMV disease was the final cause of death in patients with severe acute GVHD.  相似文献   
16.

Objective

The overall rate of suicide in French Guiana is estimated at 6 per 100,000, a rate that is lower than in mainland France. Given the frequent reports of suicide in Amerindian communities, our hypothesis was that this figure fails to capture a more contrasted reality. Our objective was to refine estimates and determine suicide rates in remote villages of French Guiana.

Methods

We included patients for whom a suicide attempt or suicide was mentioned in medical records. The Health centers were grouped into two zones according to geographical remoteness.

Results

The highest suicide rates observed in the remote Amerindian villages of Camopi and Trois Sauts were, respectively, 118 and 78/100,000. The median age at the time of suicide was significantly younger in remote zones [23 years (95% CI 21.59–25.06)] than in non-remote zones—[27 years (95% CI 24.47–29.31)]. The most frequent methods were hanging (78%) and intoxication (22%).

Conclusions

The suicide rate in remote areas in French Guiana was eight times higher than in France. The suicide of young people in remote areas in French Guiana and specifically in Amerindian villages must be better understood and prevented with contextualized and adapted care.
  相似文献   
17.

Purpose

This study was conducted to evaluate the diagnostic accuracy of axillary ultrasound (US) alone or in combination with fine-needle-aspiration cytology (FNAC) in patients with breast carcinoma, in comparison with the final histological examination (sentinel node biopsy and/or axillary dissection).

Materials and methods

Between January 2005 and June 2008, we evaluated 427 breast cancer patients with axillary US. The findings were classified according to the following criteria: hilum and cortex morphology, ratio between longitudinal and transverse diameter and ratio between hilar and longitudinal diameter of the lymph node. Patients with breast lesions ≤3 cm (n=147) underwent FNAC of the most suspicious lymph node.

Results

Overall concordance between axillary US and final histological examination was 85%, sensitivity was 72.3% and specificity was 93.4%. Concordance between FNAC and final histological examination was 93%, sensitivity was 88.1% and specificity was 100%.

Conclusions

In 48.3% of patients, the combination of axillary US and FNAC guided treatment decisions towards immediate axillary dissection, thus sparing the patients sentinel node biopsy, with a significant reduction of costs and hospitalization time.  相似文献   
18.
19.
Mammalian sperm at ejaculation are suspended in the seminal plasma, a heterogeneous mixture deriving from the testicular/epididymal fluid and from secretions of seminal vesicles, prostate and bulbourethral glands. Biochemical characteristics of seminal fluid change along the male reproductive tract when considering its inorganic and organic composition and pH but it is known that in each region of the male genital tract seminal osmolarity is higher than that of serum. It has been previously demonstrated that in invertebrate and vertebrate sperm, seminal plasma osmolarity influences sperm motility and activity, and human sperm have been shown to possess osmosensitive calcium entry pathway that controls important functions such as acrosome reaction and oocyte penetration. In the present study, we have determined seminal plasma osmolarity in a large number of normozoospermic fertile and asthenozoospermic infertile subjects correlating it with sperm motility percentages and kinematic characteristics determined utilizing a computerized motion analysis system. Our results confirm that seminal plasma osmolarity is higher than that of serum (336.1 +/- 20.2 vs. 291.1 +/- 6.9 mOsm/L, respectively). Normozoospermic subjects show seminal osmolarity values that are significantly lower with respect to asthenozoospermic patients (317.8 +/- 12.2 vs. 345.2 +/- 22.6 mOsm/L, p<0.001), irrespective of the cause of asthenozoospermia. Seminal plasma osmolarity negatively correlates with sperm progressive motility percentages and kinetic characteristics (curvilinear velocity, linear velocity, linear coefficient and lateral displacements of sperm head). Furthermore, when sperm from fertile subjects were suspended in medium with an osmolarity increasing from 300 to 600 mOsm, sperm motility percentages and kinetics characteristics were progressively reduced and nearly abolished when medium osmolarity was 600 mOsm. On the contrary, when sperm from asthenozoospermic subjects with high semen osmolarity were resuspended in medium with lower osmolarity, sperm motility parameters improved significantly. Sperm motility parameters did not correlate with seminal plasma concentrations of sodium, potassium, chloride with a weak correlation only with seminal calcium concentration. No correlations are present between seminal plasma osmolarity and ionic composition.In conclusion, the present study confirms and extends the knowledge that, in human, seminal plasma osmolarity is higher than that of serum and demonstrates that seminal osmolarity influences sperm motility characteristics and then it may contribute to the pathogenesis of some forms of asthenozoospermia and male infertility.  相似文献   
20.
PURPOSE: This prospective study tested a simple formula for selecting an implant size for patients undergoing enucleation, evisceration, and secondary implantation. The formula axial length-2 mm=implant diameter (subtract 1 mm from implant diameter for evisceration and for hyperopia) was tested by the outcome measures, superior sulcus deformity, enophthalmos, and volume of the prosthesis. METHODS: Fifty-four patients undergoing primary or secondary implant surgery after enucleation or evisceration received implants based on the above formula. The volume of the eye, volume of the implant, volume of the prosthesis, and the total percent volume replacement were recorded for each patient. Outcome measures considered clinically acceptable were <2 mm enophthalmos and less than grade 1 superior sulcus deformity, which is defined as barely perceptible deepening of the medial superior sulcus. RESULTS: The average volume replacement was 101%; average prosthetic volume was 2.1 mL; average grade of superior sulcus deformity was 0.6; and average enophthalmos was 1.2 mm. CONCLUSIONS: This formula allows 100% replacement of the volume removed, leaves space for a prosthesis 1.5 to 2.5 mL, and eliminates clinically unacceptable superior sulcus deformity and enophthalmos in 85% of patients. Patients with a history of infection, radiation, buphthalmos, or large orbital fractures (15%) had residual superior sulcus deformity greater than grade 1 and enophthalmos > or =2 mm despite 100% volume replacement. Further study will elucidate the histopathologic processes responsible for residual superior sulcus deformity and enophthalmos in the latter subgroup of patients.  相似文献   
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