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1.

Background

Inflammation and infections have been associated with prostate cancer progression. We assessed whether elevated serum cytokines or T. vaginalis seropositivity at the time of diagnosis was associated with higher grade or lethal prostate cancer.

Patients and Methods

Men with localized or metastatic prostate cancer were included in this study. Cytokine serum levels including interleukin (IL)-1α, IL-1β, IL-2, IL-6, IL-8, monocyte chemotactic protein 1 (CCL-2), tumor necrosis factor α, and growth-regulated oncogene α (CXCL-1) using a multiplex enzyme-linked immunosorbent assay and T. vaginalis serology were measured in blood samples at diagnosis.

Results

A total of 324 patients were identified at time of localized disease and 118 at time of metastatic disease. Of the 189 patients with localized disease and clinical follow-up data (median, 73 months), 28 developed lethal disease. There was no association between circulating cytokine levels above median concentrations nor T. vaginalis seropositivity and risk of intermediate- to high-risk or lethal prostate cancer.

Conclusion

Higher levels of serum cytokine levels and T. vaginalis seropositivity at diagnosis are not associated with high-grade or lethal prostate cancer and do not aid risk stratification of localized prostate cancer.  相似文献   
2.
A role for type II interferon (IFN-gamma) in resolving viral infection is suggested by the correlation of hepatitis C virus (HCV) clearance with enhancement of IFN-gamma-producing activated T cells in the resolution of acute HCV infection. Using vesicular stomatitis virus (VSV), a synergistic direct antiviral effect was documented using IFN-gamma1b and a potent, consensus type I IFN (IFN alfacon-1). Global expression profiling following EC50 exposure to IFN alfacon-1, IFN-gamma1b, or a cocktail of the two allowed the antiviral state to be correlated with induction of a subset of IFN-stimulated genes (ISGs). Genes identified through this analysis corresponded to classic antiviral components, ISGs more recently associated with direct antiviral functions, as well as expressed sequence tags (ESTs) and hypothetical proteins. The magnitude of these antiviral EC50-correlated expression events in human hepatoma (Huh7) cells exposed to clinically relevant doses of IFN alfacon-1, IFN-gamma1b, or a cocktail of the two was also probed because the standard of care for patients with chronic hepatitis C is type I IFN-containing regimens. Relative to type I IFNs used alone, the addition of type II IFN caused enhanced expression not only of many of the genes correlated with the direct antiviral state but also of genes involved in (1) antigen presentation to cytotoxic T lymphocytes (CTLs), (2) macrophage, natural killer (NK), and T helper 1 (Th1) cell recruitment and activation, (3) complement system function, (4) apoptosis, and (5) ISGs with unknown functions. As many of these processes are correlated clinically with resolution of chronic HCV infection, the combined use of these IFNs could display a beneficial effect on viral clearance in patients infected with HCV and other viruses through enhancement of one of these processes or of the direct antiviral state.  相似文献   
3.
We report Crohn's disease in an adolescent with cystic fibrosis (CF). The patient suffered from recurrent abdominal symptoms, which were attributed to distal intestinal obstruction syndrome (DIOS) until a soft tissue inflammation at the right lumbar region and iliac crest revealed an enterosubcutaneous fistula. The diagnosis of Crohn's disease was confirmed on the basis of radiological, endoscopic and histological findings.  相似文献   
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5.
ABSTRACT

Early detection of apoptotic cells on histological slides is of major importance for both diagnostic and research areas. In the current study, the aim was to propose a convenient method to stain the mitochondria and establish whether hepatocytes undergoing apoptosis can be identified in tissue sections using the proposed method. Liver tissue from five adult chinchillas was fixed with 10% neutral buffered formalin for Goldner’s trichrome (GT) and Groat’s iron hematoxylin and eosin (HE) stains and with Kolster’s fixative for the Heidenhain’s iron hematoxylin procedure. The HE and GT-stained sections showed the morphological features consistent with apoptosis i.e., homogenous intensely acidophilic cytoplasm, cell shrinkage with an irregular outline, nuclear shrinkage with cloudy karyoplasm, and karyopyknosis in the late stage. Sections stained with Heidenhain’s iron hematoxylin method was used to pinpoint mitochondria and revealed cells which were undergoing the first stages of the apoptosis process i.e., disappearance of mitochondria from the cell, chromatin condensation and margination, paracentral localization of nucleoli, and vacuolated nuclei. In more advanced stages of apoptosis, cells presented significant nuclear and cytoplasmic changes. It was concluded that this is the first report targeting the mitochondria, by performing inexpensive histological staining techniques, in order to assess dead cells in situ.  相似文献   
6.
Abundant evidence documents the highly proinflammatory actions of lysophosphatidylcholine (LPC). Further, LPC, found in high amounts in oxidized low-density lipoprotein (LDL), is implicated as an atherogenic factor. In endothelial cells, LPC impairs endothelial barrier function through GPR4, a novel receptor hypothesized to be sensitive to LPC and protons. The authors investigated the stimulation by LPC or low pH of GPR4 in human brain microvascular endothelial cells (HBMECs) and whether the activated GPR4 regulates in vitro monocyte transmigration. The results indicated that HBMECs stimulated by LPC (5 microM), but not low pH, showed a twofold increase in monocyte transmigration. Using retroviruses containing siRNA to GPR4, a > 60% reduction of GPR4 expression resulted in blockade of the LPC-stimulated transmigration. The inhibited response was restored by co-expression with an small interference RNA (siRNA)-resistant, but functional, GPR4 mutant construct. To investigate potential signaling mechanisms, the siRNA-mediated knockdown of GPR4 also prevented LPC-induced RhoA activation. C3 transferase, a Rho inhibitor, prevented approximately approximately 65% of the LPC-stimulated transmigration. LPC also increased MLC phosphorylation by 5 min, which was inhibited by the Rho kinase inhibitor, Y-27632 (10 microM) or ML-7 (myosin light chain kinase (MLCK) inhibitor). The findings indicate that the proinflammatory and atherogenic LPC stimulated endothelial GPR4, which promoted monocyte transmigration through a RhoA-dependent pathway.  相似文献   
7.
8.
Interactions of Haemophilus influenzae with cultured human endothelial cells   总被引:15,自引:0,他引:15  
The interactions of capsulate (b+) and capsule-deficient (b-) Haemophilus influenzae type b with endothelial cells were studied in vitro using human umbilical vein endothelial cells (Huvecs). Association was determined by estimation of colony forming units (cfu) as well as the binding of 3H-thymidine-labelled bacteria. Bacteria associated with Huvecs rapidly and in a dose-dependent manner. The presence of capsule on bacteria resulted in a decrease in the rate of cell-association. Internationalisation of bacteria by Huvecs was quantitated after elimination of extracellular bacteria with gentamicin. It was found that larger numbers of b- bacteria were internalised compared to b+ bacteria. Incubation in the presence of metabolic inhibitors had little effect on the association of bacteria to Huvecs whereas internalisation was dependent on the integrity of host cellular functions. Electron microscopic studies confirmed phagocytic ingestion of both b+ and b- variants and suggested that the majority of the internalised bacteria remained viable within endothelial cell vacuoles. Haemophilus influenzae were translocated within vacuoles both from the apical to basal and the basal to apical direction.  相似文献   
9.
Objectives. To test the hypothesis that transgenic mouse models of prostate cancer could be useful for testing chemoprevention strategies by evaluating the effects of early castration on prostate carcinogenesis in TRAMP mice. Human prostate cancer, unlike other cancers, requires androgens for oncogenesis yet acquires partial androgen independence in the castrated milieu. This paradigm is the basis for an ongoing clinical trial using selective androgen deprivation for prostate cancer chemoprevention. However, preclinical correlates for hormonal prevention or other chemoprevention strategies of prostate cancer have not previously been demonstrated in autochthonous models of prostate carcinogenesis.Methods. Magnetic resonance imaging was used to longitudinally measure prostate growth in castrated and noncastrated TRAMP mice, and mice were prospectively examined for the onset of advanced, palpable prostate cancer. Modulation of androgen-responsive oncogene expression, as well as oncogene expression in refractory cancers, was evaluated by Western blot.Results. Early castration significantly reduced prostate tumor growth as measured by magnetic resonance imaging and improved cancer-free survival. Prevention of prostate cancer development in these mice was associated with durable suppression of androgen-responsive oncogene expression (T-antigen expression not detectable by Western blot); prostate cancers refractory to the hormonal prevention strategy demonstrated androgen-independent oncogene expression.Conclusions. These findings suggest that carcinogenesis related to androgen-responsive oncogene expression can be prevented in some cases by hormonal manipulation and that transgenic TRAMP mice are useful for the preclinical evaluation of hormonal and possibly other strategies of prostate cancer chemoprevention.  相似文献   
10.
Serum prostate-specific antigen (PSA) levels and the biopsy Gleason sum are used along with clinical staging to predict prostatectomy pathology results for men with localized prostate cancer. The additional predictive value of perineural invasion (PNI) in pretreatment prostate needle biopsies for evaluating tumor stage in this setting is controversial. The current study evaluates the independent predictive value of PNI for tumor staging in a cohort of 632 men who underwent radical retropubic prostatectomies for clinically localized adenocarcinoma of the prostate between the years 1994 and 1998. None of these men received hormonal or radiation therapy before surgery. In addition to the Gleason sum, biopsy results contained detailed information regarding tumor burden: 1) total number of biopsy cores involved by adenocarcinoma, 2) greatest percentage of any single biopsy involved by prostate carcinoma (GPC), and 3) total percentage of cancer added over all cores (TPC). The presence or absence of any PNI was recorded. Pretreatment factors were analyzed in a univariate and multivariate fashion to determine their predictive value using the TNM tumor stage (pT2 vs pT3) and the modified tumor staging system, which includes surgical margin status (pT2 vs pT3 or positive surgical margin) as end points. Univariate analysis revealed a significant association between pT3 disease and several preoperative factors including age, Gleason sum, serum PSA, digital rectal examination, PNI, GPC, TPC, and the total number of positive cores (p <0.01). Multivariate analysis indicated that serum PSA, Gleason sum, age, and GPC contributed significantly to predicting pT3 disease with odds ratios of 2.7 (95% CI, 1.7-4.3), 2.3 (95% CI, 1.7-3.1), 1.7 (95% CI, 1.1-2.7), and 1.7 (95% CI, 1.4-2.1) respectively. PNI was significant in multivariate analysis only when GPC and TPC were not considered, due to a significant interaction between GPC and PNI (p <0.0001, Wilcoxon's rank sum test). These predictive factors showed a similar relationship to adverse pathology when an alternative definition of adverse pathology was used that included positive surgical margins (pT3 or any positive margin). In the interaction between GPC and PNI, GPC was more significant than PNI in predicting pT3 disease. However, PNI added additional information when adverse pathology was defined more broadly as pT3 or any positive margin.  相似文献   
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