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101.
The induction of regulatory T (T reg) cells holds considerable potential as a treatment for autoimmune diseases. We have previously shown that CD4+CD25hi T reg cells isolated from patients with active rheumatoid arthritis (RA) have a defect in their ability to suppress proinflammatory cytokine production by CD4+CD25- [corrected] T cells. This defect, however, was overcome after anti-tumor necrosis factor (TNF)-alpha antibody (infliximab) therapy. Here, we demonstrate that infliximab therapy gives rise to a CD4+CD25hiFoxP3+ T reg cell population, which mediates suppression via transforming growth factor (TGF)-beta and interleukin 10, and lacks CD62L expression, thereby distinguishing this T reg cell subset from natural T reg cells present in healthy individuals and patients with active RA. In vitro, infliximab induced the differentiation of CD62L- T reg cells from CD4+CD25- T cells isolated from active RA patients, a process dependent on TGF-beta. In spite of the potent suppressor capacity displayed by this CD62L- T reg cell population, the natural CD62L+ T reg cells remained defective in infliximab-treated patients. These results suggest that anti-TNF-alpha therapy in RA patients generates a newly differentiated population of T reg cells, which compensates for the defective natural T reg cells. Therefore, manipulation of a proinflammatory environment could represent a therapeutic strategy for the induction of T reg cells and the restoration of tolerance.  相似文献   
102.
The study consisted of application of anti-ubiquitin antibodies (Abs)-coated iron oxide-nanoparticles (IONPs) for minimisation of oxidative stress to contemporary live spermatozoa from the raw semen. Round-shaped IONPs (12.09 ± 0.91 nm) after two-stage functionalisation (silanisation and pegylation) were conjugated with Abs. Four aliquots from each of the 24 ejaculates (4 buffalo bulls) formed Control (Group I) and treatment (II, III and IV) groups; each containing 150 ± 25 million dead/damaged spermatozoa. IONPs-Abs complex were added at ratio of 1:1 (0.5 µg/ml), 1:2 (1.0 µg/ml) and 1:4 (2.0 µg/ml), respectively, in Groups II, III and IV. The semen quality parameters showed improvement at lag-stage (post-nano-purification before processing for cryopreservation). The mean post-thaw motility (%) in Group IV was found to be greater (p < .05) than Group I. Moreover, the overall DNA integrity (%) at post-thaw stage was improved in the nano-purified semen samples. The value of malondialdehyde was greater (p < .001) in Group I than Groups II, III and IV. The mean total antioxidant capacity and superoxide dismutase (U/mg protein) activity values in Group IV was greater (p < .05) than Group I. The study results show that IONPs conjugated with anti-ubiquitin Abs at 2.0 µg/ml can be an effective dose for depletion of dead/damaged spermatozoa from buffalo ejaculates to minimise oxidative stress.  相似文献   
103.
104.
The 3C-like protease (3CLpro) of SARS-CoV-2 is considered an excellent target for COVID-19 antiviral drug development because it is essential for viral replication and has a cleavage specificity distinct from human proteases. However, drug development for 3CLpro has been hindered by a lack of cell-based reporter assays that can be performed in a BSL-2 setting. Current efforts to identify 3CLpro inhibitors largely rely upon in vitro screening, which fails to account for cell permeability and cytotoxicity of compounds, or assays involving replication-competent virus, which must be performed in a BSL-3 facility. To address these limitations, we have developed a novel cell-based luciferase complementation reporter assay to identify inhibitors of SARS-CoV-2 3CLpro in a BSL-2 setting. The assay is based on a lentiviral vector that co-expresses 3CLpro and two luciferase fragments linked together by a 3CLpro cleavage site. 3CLpro-mediated cleavage results in a loss of complementation and low luciferase activity, whereas inhibition of 3CLpro results in 10-fold higher levels of luciferase activity. The luciferase reporter assay can easily distinguish true 3CLpro inhibition from cytotoxicity, a powerful feature that should reduce false positives during screening. Using the assay, we screened 32 small molecules for activity against SARS-CoV-2 3CLpro, including HIV protease inhibitors, HCV protease inhibitors, and various other compounds that have been reported to inhibit SARS-CoV-2 3CLpro. Of these, only five exhibited significant inhibition of 3CLpro in cells: GC376, boceprevir, Z-FA-FMK, calpain inhibitor XII, and GRL-0496. This assay should greatly facilitate efforts to identify more potent inhibitors of SARS-CoV-2 3CLpro.  相似文献   
105.
BackgroundDiabetic Retinopathy (DR) is an important microvascular complication of diabetes that can lead to irreversible blindness. Microalbuminuria is strongly associated with diabetic retinopathy and can be used as a reliable marker of diabetic retinopathy.AimTo assess the association between DR, microalbuminuria, and other modifiable risk factors in patients with type 2 diabetes.Methodology3090 patients with T2DM visiting North Delhi Diabetes Centre, New Delhi between July 2016 to October 2019 were evaluated for the clinical and biochemical parameters that included urinary albumin, HbA1C, lipid profiles, serum creatinine estimation and underwent biothesiometry.Results3090 patients (1350 females and 1740 males), with mean age of 52.7 ± 9.2 years and diabetes duration ranging from 1 to 19 years (mean 9.4 ± 6), duration of less than 5 years, 6–10 years and more than 10 years in 52%, 26% and in 22%, respectively. Duration of diabetes was strong predictor of retinopathy (p = 0.001). The HbA1c and BMI in patients with DR was significantly higher than in those without DR. 18.2% patients were diagnosed to have retinopathy. Peripheral neuropathy was observed in 24.2% and was positively associated with DR (p = 0.002). 33.9% and 4.5% patients had microalbuminuria macroalbuminuria, respectively and 9.7% patients had creatinine >1.3 mg/dL. There was significant positive relationship between different grades of retinopathy and albuminuria.ConclusionsOur study is a large real-world study that demonstrates that HbA1c, BMI, duration of diabetes, microalbuminuria and peripheral neuropathy are relatively, yet cohesively contributing factors towards varying grade of retinopathy.  相似文献   
106.
Gill  Tania S.  Varghese  Bino A.  Hwang  Darryl H.  Cen  Steven Y.  Aron  Manju  Aron  Monish  Duddalwar  Vinay A. 《Abdominal imaging》2019,44(4):1470-1480
Purpose

The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1–2) versus high-grade (ISUP 3–4) clear cell renal cell carcinoma (ccRCC).

Methods

In this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively.

Results

All methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75.

Conclusions

Our study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.

  相似文献   
107.
Disruption of spermatogenesis found in azoospermia and oligozoospermia is thought to be of primarily genetic origin. Sl/Sl(d) mutant mice offer a model system in which lack of transmembrane type c-kit ligand (KL2) expression on the somatic Sertoli cell surface results in disruption of spermatogenesis. We investigated the ability of adeno-, adeno-associated-, retro-, and lentiviral vectors to transduce Sertoli cells and found that transduction with either adeno- or lentiviral vectors led to reporter gene expression for more than 2 mo after testicular tubule injection. Because adenoviral vectors showed toxicity, lentiviral vectors were used to express the c-kit ligand in Sl/Sl(d) Sertoli cells. Restoration of spermatogenesis was observed in all recipient testes. Furthermore, the sperm collected from recipient testes were able to generate normal pups after intracytoplasmic sperm injection. None of the offspring carried the transgene, suggesting the inability of lentiviral vectors to infect spermatogenic cells in vivo. We propose that lentiviral vectors can be used for gene therapy of male infertility without the risk of germ-line transmission.  相似文献   
108.
Summary Many anticancer drugs exert their cytotoxic effects via formation of oxygen free radicals. Cellular thiols, glutathione (GSH)-dependent enzymes and other redox enzymes are involved in the metabolism of these anticancer drugs and of the oxygen free radicals that may be generated during their metabolism. We quantified these biochemical parameters in cytosol from human ovarian tissues. We compared non-protein thiol levels, GSH transferase, GSH peroxidase, Superoxide dismutase, catalase, DT diaphorase and aldehyde dehydrogenase activity in serous ovarian tumors (n=15), other malignant ovarian tumors (n=12), benign ovarian tissue (n=10) and histologically normal ovarian tissue (n=12). Mean GSH transferase and DT diaphorase activitie were similar in serous and other malignant ovarian tumors. GSH transferase activity was decreased in malignant tissues relative to normal and benign tissues. Mean DT diaphorase and Superoxide dismutase activities were increased in the malignant tissues, although this was not statistically significant. The mean levels of all anzymes except Superoxide dismutase and aldehyde dehydrogenase in benign tissues were fairly similar to the mean levels found in normal tissue samples. Tissues from patients with serous ovarian tumors, who had received cyclophosphamide and cisplatin prior to surgery, also were analyzed (n=7). Except for aldehyde dehydrogenase, all the parameters measured were decreased in these samples relative to serous tissue from untreated patients. These biochemical analyses may be useful in understanding the mechanisms involved in the response to chemotherapy.Abbreviations ANOVA analysis of variance - GSH glutathione Partial support for this study was obtained from the Comprehensive Cancer Center of Metropolitan Detroit, core grant CA-22453, National Institutes of Health.  相似文献   
109.

Objective

The aim of this work was to evaluate the hypothesis that the distribution of circulating immune cell subsets, or their activation state, is significantly different between peripartum cardiomyopathy (PPCM) and healthy postpartum (HP) women.

Background

PPCM is a major cause of maternal morbidity and mortality, and an immune-mediated etiology has been hypothesized. Cellular immunity, altered in pregnancy and the peripartum period, has been proposed to play a role in PPCM pathogenesis.

Methods

The Investigation of Pregnancy-Associated Cardiomyopathy (IPAC) study enrolled 100 women presenting with a left ventricular ejection fraction of <0.45 within 2 months of delivery. Peripheral T-cell subsets, natural killer (NK) cells, and cellular activation markers were assessed by flow cytometry in PPCM women early (<6 wk), 2 months, and 6 months postpartum and compared with those of HP women and women with non–pregnancy-associated recent-onset cardiomyopathy (ROCM).

Results

Entry NK cell levels (CD3–CD56+CD16+; reported as % of CD3– cells) were significantly (P?<?.0003) reduced in PPCM (6.6?±?4.9% of CD3– cells) compared to HP (11.9?±?5%). Of T-cell subtypes, CD3+CD4–CD8–CD38+ cells differed significantly (P?<?.004) between PPCM (24.5?±?12.5% of CD3+CD4–CD8– cells) and HP (12.5?±?6.4%). PPCM patients demonstrated a rapid recovery of NK and CD3+CD4–CD8–CD38+ cell levels. However, black women had a delayed recovery of NK cells. A similar reduction of NK cells was observed in women with ROCM.

Conclusions

Compared with HP control women, early postpartum PPCM women show significantly reduced NK cells, and higher CD3+CD4–CD8–CD38+ cells, which both normalize over time postpartum. The mechanistic role of NK cells and “double negative” (CD4–CD8–) T regulatory cells in PPCM requires further investigation.  相似文献   
110.
Familial hemophagocytic lymphohistiocytosis (FHL) is an inherited, fatal disorder of infancy. We report here a 17-day-old female infant who presented with high fever, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, thrombocytopenia, and liver failure. Leukocytosis was detected with circulating "atypical" lymphoid cells. Flow cytometric studies revealed expanded subpopulations of CD8+ T cells with unusual immunophenotypic features, including a subset that lacked CD5 expression. A liver biopsy showed hemophagocytic lymphohistiocytosis with exuberant infiltrates of CD8+ T cells that lacked perforin. Mutational studies revealed a 666C-->A (H222Q) missense mutation in the perforin gene. T-cell receptor studies on flow-sorted T-cell subpopulations revealed no evidence of monoclonality. Analysis of T-cell receptor excision circle levels indicated long proliferative history in the aberrant CD8+ T-cell subsets. This case provides an instructive example of uncontrolled reactive proliferation of CD8+ T cells in FHL, resulting in atypical morphology and unusual immunophenotypic features that might suggest malignancy in other clinical settings.  相似文献   
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