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991.
Bcl-2 proteins represent a rheostat that controls cellular viability. Obatoclax, a BH3-mimetic, has been designed to specifically target and counteract anti-apoptotic Bcl-2 proteins. We evaluated the biological effects of obatoclax on the anti-tumour activity of rituximab and chemotherapy agents. Obatoclax induced cell death of rituximab/chemotherapy-sensitive (RSCL), -resistant cell lines (RRCL) and primary tumour-cells derived from patients with B-cell lymphomas (N=39). Obatoclax also enhanced the activity of rituximab and had synergistic activity when combined with chemotherapy agents. The ability of Obatoclax to induce PARP cleavage varied between patient samples and was not observed in some RRCL. Inhibition of caspase activity did not affect obatoclax activity, suggesting the existence of caspase-independent death pathways. Autophagy was detected by LC3 conversion and/or electron microscopy in RRCL and in patient-derived tumour cells. Moreover, obatoclax activity was inhibited by Beclin-1 knockdown. In summary, obatoclax is an active Bcl-2 inhibitor that potentiates the activity of chemotherapy agents and, to a lesser degree, rituximab. Defining the molecular events triggered by obatoclax is necessary to further its clinical development and identify potential biomarkers that are predictive of response.  相似文献   
992.
A 52-year-old woman presented with fracture upper end of the left humerus after trivial trauma and aspiration cytology from the lytic lesion in the upper humerus seen on X-ray revealed a metastatic papillary carcinoma from the thyroid. Total thyroidectomy confirmed the papillary carcinoma thyroid. Post-operatively, she was given radioactive iodine (I-131) ablation therapy for 8 years and was asymptomatic during this period; however, for the last 1 year, she has been complaining of swelling in the shoulder, which did not respond to palliative radiotherapy and rapidly increased in size. Disarticulation of the shoulder joint was performed, which showed anaplastic carcinoma on histopathological examination. Anaplastic transformation of papillary carcinoma at the metastatic sites is well documented in the literature and is rare. However, the same has not been reported at the shoulder and from India before. Although soft tissue sarcomas are most common at this site, however, the possibility of anaplastic transformation should be kept in the differential diagnosis of rapidly enlarging painful mass in a known case of metastatic thyroid carcinoma to prevent misdiagnosis.  相似文献   
993.
The accepted standard treatment of war wounds through the last century has been debridement and delayed primary closure. However, recently, there has been a renewed Interest In primary closure of these wounds. 1481 war wounds were managed by the authors and out of 789 soft tissue injuries, 389 (47%) were closed primarily (group 1) after meticulous debridement and 220 (28%) underwent delayed primary closure (group 2). The infection rate in group 1 was 4.87% compared to 6.36% in group 2. The average hospital stay in group 1 was 15 days, significantly shorter by 10 days than in group 2. In the war zone both time and resources are at a premium and primary closure of selected wounds offers a better alternative to delayed primary closure.Key Words: Debridement, Delayed primary closure, Primary closure, War Wounds  相似文献   
994.
Despite progress in recent years, pancreatic cancer still remains a major clinical challenge. Its incidence and mortality rates have been on consistent rise underscoring the critical need for novel diagnostic, prognostic and therapeutic tools for its effective management. Recent studies have demonstrated that microRNAs (miRNAs/miRs) are deregulated in a variety of malignancies, including pancreatic cancer, and play a significant role in the initiation, progression and metastasis. Furthermore, their vital involvement in the therapeutic resistance of cancer has also been established. Hence, there has been enormous interest worldwide in investigating the roles of miRNAs in pancreatic cancer pathogenesis and exploiting their utility for clinical benefit. In this review, we summarize current knowledge on the role of miRNAs in pancreatic cancer and discuss their potential use as diagnostic and prognostic biomarkers, and as novel targets for development of effective therapeutic strategies.  相似文献   
995.
The receptor activator of nuclear factor-κB ligand (RANKL) acts as a paracrine factor in progesterone-induced mammary epithelial proliferation and tumorigenesis. This evidence comes mainly from mouse models. Our aim was to examine whether RANKL expression in human normal and malignant breast is under the control of progesterone throughout the menstrual cycle. Breast epithelial samples were obtained by random fine needle aspiration (rFNA) of the contralateral unaffected breasts (CUB) of 18 breast cancer patients, with simultaneous serum hormone measurements. Genes correlated with serum progesterone levels were identified through Illumina microarray analysis. Validation was performed using qRT-PCR in rFNA samples from CUB of an additional 53 women and using immunohistochemistry in tissue microarrays of 61 breast cancer samples. Expression of RANKL, DIO2, and MYBPC1 was correlated with serum progesterone in CUB, and was significantly higher in luteal phase. RANKL and MYBPC1 mRNA expression were highly correlated between CUB and matched tumor samples. RANKL protein expression was also significantly increased in the luteal phase and highly correlated with serum progesterone levels in cancer samples, especially in hormone receptor positive tumors. The regulatory effects of progesterone on the expression of RANKL, DIO2, and MYBPC1 were confirmed in three-dimensional cultures of normal breast organoids. In normal breast and in breast cancer, RANKL mRNA and protein expression fluctuate with serum progesterone with highest levels in the luteal phase, suggesting that RANKL is a modulator of progesterone signaling in normal and malignant breast tissue and a potential biomarker of progesterone action and blockade.  相似文献   
996.
Kini SP  DeLong LK 《Dermatologic Clinics》2012,30(2):209-21, xiii
The concept of quality of life (QOL) is becoming increasingly important in medicine, particularly in dermatology where many cutaneous diseases have the potential to affect the quality rather than the length of life. There is increasing interest in devising methodology to accurately measure the impact of disease on QOL for use in clinical practice, research studies, and economic analyses. The question of which dermatologic QOL instruments to choose inevitably arises. The aim of this article is to familiarize readers with health status measures and to review their use in dermatology.  相似文献   
997.
Abstract Background: Mohs surgery allows excision of skin cancer in a tissue-sparing fashion that minimizes recurrence risk. While the indications for Mohs surgery are well established, factors predictive of complex Mohs cases are less studied. Objective: To determine patient, tumor, and surgeon characteristics associated with complex Mohs cases. Methods: A retrospective review was performed for a 3-year period (7/2006-6/2009) to identify Mohs cases requiring ≥4 stages ("complex"), and a control population requiring ≤3 stages ("non-complex"). Surgical logs for four fellowship-trained Mohs surgeons were reviewed. Results: 77 complex cases (51 academic practice vs. 26 private practice) were compared with 154 control cases (102 academic practice vs. 52 private practice). There were no significant differences in patient age, gender, immunosuppression, academic (2.7% complex) versus private practice (3.5% complex), or surgeons' years of experience. Factors associated with complexity included: recurrent tumors (p < 0.001; odds ratio (OR) 6.88; 95% confidence interval (CI) 2.8-17); basal cell carcinoma (BCC) with infiltrative or morpheaform histology (p = 0.0019; OR 3.0; 95% CI 1.5-6.3); tumors of the nose (p = 0.0168; OR 2.05; 95% CI 1.1-3.7), especially nasal tip (p = 0.0103; OR 3.68; 95% CI 1.3-10.6) and ear (p = 0.0178; OR 3.0; 95% CI 1.2-7.9), especially helix (p = 0.00744; OR 5.9; 95% CI 1.5-22.7); tumors with pre-operative size >1 cm (p = 0.018; OR 2.0; 95% CI 1.1-3.6); and tumors involving >1 cosmetic subunit (p = 0.0072; OR 5.0; 95% CI 1.5-16.7). Complex tumors had greater post-operative area (10.6 ± 1.3 vs. 3.6 ± 0.7 cm(2); p < 0.0001), and more often required flap/graft repair (p < 0.0001; OR 6.9; 95% CI 3.7-13.1). Limitations: A retrospective study representing a single geographic area. Conclusions: Mohs cases are similar in complexity whether in academic or private practice. Recurrent/aggressive histology tumors, tumors >1 cm, and tumors on the nose or ear are more likely to prove surgically complex. Advanced knowledge of these factors may be useful pre-operatively as Mohs surgeons plan their scheduled cases.  相似文献   
998.
In vitro metabolite profiling and characterization experiments are widely employed in early drug development to support safety studies. Samples from incubations of investigational drugs with liver microsomes or hepatocytes are commonly analyzed by liquid chromatography/mass spectrometry for detection and structural elucidation of metabolites. Advanced mass spectrometers with accurate mass capabilities are becoming increasingly popular for characterization of drugs and metabolites, spurring changes in the routine workflows applied. In the present study, using a generic full-scan high-resolution data acquisition approach with a time-of-flight mass spectrometer combined with postacquisition data mining, we detected and characterized metabonates (false metabolites) in microsomal incubations of several alkylamine drugs. If a targeted approach to mass spectrometric detection (without full-scan acquisition and appropriate data mining) were employed, the metabonates may not have been detected, hence their formation underappreciated. In the absence of accurate mass data, the metabonate formation would have been incorrectly characterized because the detected metabonates manifested as direct cyanide-trapped conjugates or as cyanide-trapped metabolites formed from the parent drugs by the addition of 14 Da, the mass shift commonly associated with oxidation to yield a carbonyl. This study demonstrates that high-resolution mass spectrometry and the associated workflow is very useful for the detection and characterization of unpredicted sample components and that accurate mass data were critical to assignment of the correct metabonate structures. In addition, for drugs containing an alkylamine moiety, the results suggest that multiple negative controls and chemical trapping agents may be necessary to correctly interpret the results of in vitro experiments.  相似文献   
999.
Public service utilization data are often used as key outcomes in studies on homelessness. Although self‐report data on these outcomes are accessible and cost‐effective, various factors may affect retrospective recall in homeless populations. It is therefore necessary to establish validity of self‐report to ensure the integrity of studies involving such populations. Participants (N=134) were chronically homeless individuals with severe alcohol problems who participated in a housing first effectiveness trial (Larimer et al., 2009 ). The authors compared 30‐day and 3‐year retrospective self‐report data on sobering center, jail, and hospital use with archival records corresponding to the same timeframes. Analyses indicated good category‐specific agreement for 30‐day self‐report and archival data on sobering center (82%; κ=.58) and jail use (89%; κ=.60). Hospital use, however, was self‐reported significantly more frequently than indicated by archival data (78%; κ=.30). Three‐year data showed inadequate agreement across all three variables. © 2011 Wiley Periodicals, Inc.  相似文献   
1000.
Generation of alloantibodies to transfused RBCs can be a serious medical problem for patients who require chronic RBC transfusion therapy. Patients with sickle cell disease have a substantially increased rate of alloimmunization compared to other chronically transfused populations. A recent study has forwarded the hypothesis that a polymorphism in an immunoregulatory gene in close proximity to beta-globin (TRIM21 rs660) plays a role in the increased rates of RBC alloimmunization in sickle cell patients. In particular, it was hypothesized that rs660C/T decreases expression of TRIM21, resulting in loss of a negative feedback pathway in immune responses and increased RBC alloimmunization. To test the effects of TRIM21 expression on alloimmunization, we analyzed antibody responses to alloantigens on RBCs and platelets transfused into wild-type and TRIM21 KO mice. No significant increases were seen in the frequency or magnitude of humoral immunization to alloantigens on transfused RBCs or platelets in adult or juvenile TRIM21 KO recipients compared to wild-type controls. Moreover, recipient inflammation with poly (I:C) enhanced RBC alloimmunization to similar degrees in both TRIM21 KO and wild-type control recipients. Together, these data rule out the hypothesis that decreased TRIM21 expression enhances transfusion induced humoral alloimmunization, in the context of a reductionist murine model.  相似文献   
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