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81.
Early diagnosis of hepatocellullar carcinoma (HCC) remains a challenge. The current practice of serum alpha-fetoprotein (AFP) measurement is inadequate. Here we utilized a proteomic approach to identify novel serum biomarkers for distinguishing HCC patients from non-cancer controls. We profiled the serum proteins in a group of 58 resectable HCC patients and 11 non-HCC chronic hepatitis B (HBV) carrier samples from the Singapore General Hospital (SGH) using the RayBio® L-Series 507 Antibody Array and found 113 serum markers that were significantly modulated between HCC and control groups. Selected potential biomarkers from this list were quantified using a multiplex sandwich enzyme-linked immunosorbent assay (ELISA) array in an expanded SGH cohort (126 resectable HCC patients and 115 non-HCC chronic HBV carriers (NC group)), confirming that serum prolactin and monocyte chemoattractant protein-1 (MCP-1) were significantly upregulated in HCC patients. This finding of serum MCP-1 elevation in HCC patients was validated in a separate cohort of serum samples from the Mochtar Riady Institute for Nanotechnology, Indonesia (98 resectable HCC, 101 chronic hepatitis B patients and 100 asymptomatic HBV/HCV carriers) by sandwich ELISA. MCP-1 and prolactin levels were found to correlate with AFP, while MCP-1 also correlated with disease stage. Subsequent receiver operating characteristic (ROC) analysis of AFP, prolactin and MCP-1 in the SGH cohort and comparing their area under the ROC curve (AUC) indicated that neither prolactin nor MCP-1 on their own performed better than AFP. However, the combination of AFP+MCP-1 (AUC, 0.974) had significantly superior discriminative ability than AFP alone (AUC, 0.942; p<0.001). In conclusion, prolactin and MCP-1 are overexpressed in HCC and are conveniently quantifiable in patients’ sera by ELISA. MCP-1 appears to be a promising complementary biomarker for HCC diagnosis and this MCP-1+AFP model should be further evaluated as potential biomarker on a larger scale in patients at-risk of HCC.  相似文献   
82.
Protein aggregation during expression, purification, storage, or transfer into requisite assay buffers hampers the use of proteins for in vitro studies. The formation of these aggregates represents a major obstacle in the study of biological activity and also restricts the spectrum of protein products being available for the biomedical applications. The catalytic light chain of botulinum neurotoxin type A undergoes autocatalysis and aggregation after purification upon long-term storage and freeze-thawing. In present study the conditions for the high level expression and purification of biologically active light chain protein of botulinum neurotoxin were optimized from a synthetic gene. Several co-solvents were screened in order to prevent autocatalysis and aggregation of rBoNT/A-LC. The effect of the co-solvents is studied on endopeptidase activity during long term storage of the recombinant protein. The purified rBoNT/A-LC was also evaluated for its immunogenicity.  相似文献   
83.
Botulinum neurotoxins (BoNTs) are highly potent toxins that inhibit neurotransmitter release from peripheral cholinergic synapses. The gene for encoding the full length light chain with H(CC) (binding) domain of Clostridium botulinum neurotoxin A was synthesized and cloned into a bacterial expression vector pQE30-UA and produced as an N-terminally six-histidine-tagged fusion protein (rBoNT/A LC-H(CC)). This protein was expressed in two different strains of Escherichia coli namely BL21(DE3) and SG13009. Expression at 37 °C revealed localization of rBoNT/A LC- H(CC) in inclusion body whereas it was expressed in soluble form at 21°C. The recombinant fusion protein was purified by nickel affinity gel column chromatography and identified by monoclonal antibody and peptide mass fingerprinting. The recombinant protein was shown to bind with synaptic vesicles and gangliosides (GT1b) using enzyme-linked immunosorbent assay. The rBoNT/A LC-H(CC) was also found to be highly active on its substrate (SNAP-25) from rat brain, indicating that the expressed and purified rBoNT/A LC-H(CC) protein retains a functionally active conformation. Biologically active recombinant fusion protein was also evaluated for its immunological potential.  相似文献   
84.
A series of cinnamide derivatives was designed as potential antimycobacterial agents using molecular hybridization approach. The diamine moiety, a key feature of ethambutol and its other analogs, and certain structural features of cerulenin and cinnamic acid were hybridized to obtain cinnamide derivatives. The minimum inhibitory concentration (MIC) of all synthesized compounds was determined against M. tuberculosis H37Rv using Resazurin Microtitre plate Assay (REMA) method. The synthesized molecules showed good to moderate activity with MIC in the range of 5-150 μM and good safety profile. Additionally, the most potent compound 1a, having MIC 5.1 μM exhibited synergy with rifampicin.  相似文献   
85.

Background

Previous studies examining sex-related differences in the treatment of coronary artery disease have focused on patients in hospital. We sought to examine sex-related differences at an earlier point in care — presentation to the emergency department.

Methods

We collected data on ambulatory care and hospital admissions for 54 134 patients (44% women) who presented to an emergency department in Alberta between July 1998 and March 2001 because of acute myocardial infarction, unstable angina, stable angina or chest pain. We used logistic regression and Cox regression analyses to determine sex-specific associations between the likelihood of discharge from the emergency department or coronary revascularization within 1 year and 1-year mortality after adjusting for age, comorbidities and socioeconomic factors.

Results

Following the emergency department visit, 91.3% of patients with acute myocardial infarction, 87.4% of those with unstable angina, 40.7% of those with stable angina and 19.8% of those with chest pain were admitted to hospital. Women were more likely than men to be discharged from the emergency department: adjusted odds ratio (and 95% confidence interval [CI]) 2.25 (1.75–2.90) for acute myocardial infarction, 1.71 (1.45–2.01) for unstable angina, 1.33 (1.15–1.53) for stable angina and 1.46 (1.36–1.57) for chest pain. Women were less likely than men to undergo coronary revascularization within 1 year: adjusted odds ratio (and 95% CI) 0.65 (0.57–0.73) for myocardial infarction, 0.39 (0.35–0.44) for unstable angina, 0.35 (0.29–0.42) for stable angina and 0.32 (0.27–0.37) for chest pain. Female sex had no impact on 1-year mortality among patients with acute myocardial infarction; it was associated with a decreased 1-year mortality among patients with unstable angina, stable angina and chest pain: adjusted hazard ratio (and 95% CI) 0.60 (0.46–0.78), 0.60 (0.46–0.78) and 0.74 (0.63–0.87) respectively.

Interpretation

Women presenting to the emergency department with coronary syndromes are less likely than men to be admitted to an acute care hospital and to receive coronary revascularization procedures. These differences do not translate into worse outcomes for women in terms of 1-year mortality.For patients experiencing a new-onset acute cardiac event, the emergency department is usually the point of first contact with the health care system. A fraction of patients presenting to the emergency department are admitted to an acute care hospital for treatment or continued observation. Given that decisions made in the emergency department govern not only immediate but also longer-term treatment and outcomes, it is imperative that these decisions be appropriate.The issue of gender bias in the treatment and outcomes of coronary artery disease has been examined extensively. The current guidelines of the American College of Cardiology and American Heart Association state that the treatment of acute coronary syndromes in women should be no different from that in men.1,2 However, several studies have found evidence to the contrary. There is general consensus that the frequency of cardiac catheterization is lower among women and that they undergo fewer revascularization procedures.3–11 Whether these lower rates are due to an inherent gender bias or indicate appropriate care continues to be debated.Most studies of gender bias in cardiovascular care have focused either on patients in an acute care facility or on selected patient populations, such as those who have undergone cardiac catheterization. The few studies that have examined sex-specific differences in treatment decisions earlier in the process of care (i.e., in the emergency department) have either been single-centre studies12 or have involved clinical trial patients.13 Moreover, examination of sex-specific differences in cardiac care has traditionally been limited to more acute conditions, such as acute myocardial infarction and unstable angina.5,10,11,14–21 There is a need to expand our evaluation to a wider spectrum of coronary syndromes. We undertook the current study (a) to examine differences in rates of admission to acute care hospitals between men and women presenting to the emergency department with a main ambulatory care diagnosis of acute myocardial infarction, unstable angina, stable angina or chest pain and (b) to determine whether a patient''s sex is an independent predictor of 1-year treatment and outcomes in this cohort of patients.  相似文献   
86.
We earlier reported the mitogenic and immunostimulatory activities of Rhizoctonia bataticola lectin (RBL), purified from phytopathogenic fungus R. bataticola in human PBMC. The lectin demonstrates specificity towards glycoproteins containing complex N-glycans. Since CD45-protein tyrosine phosphatase that abundantly expresses N-glycans is important in T-cell signaling, the study aimed to investigate the involvement of CD45 in the immunomodulatory activities of RBL. Flowcytometry and confocal microscopy studies revealed that RBL exhibited binding to PBMC and colocalized with CD45. The binding was comparable in cells expressing different CD45 isoforms-RA, -RB and -RO. CD45 blocking antibody reduced the binding and proliferation of PBMC induced by RBL. CD45-PTPase inhibitor dephostatin inhibited RBL-induced proliferation, expression of CD25 and pZAP-70. RBL-induced secretion of Th1/Th2 cytokines were significantly inhibited in presence of dephostatin. Also, dephostatin blocked phosphorylation of p38MAPK and STAT-5 that was crucial for the biological functions of RBL. The study demonstrates the involvement of CD45-mediated signaling in RBL-induced PBMC proliferation and Th1/Th2 cytokine secretion through activation of p38MAPK and STAT-5.  相似文献   
87.
Pregnancy occurs rarely in patients with Cushing syndrome (CS) due to hypercortisolism. So far, about 150 cases of CS in pregnancy have been reported in the literature. We describe a 22-year-old female who presented in pregnancy with clinical features of CS. She delivered at 34 weeks of gestation and baby had transient adrenal insufficiency in the neonatal period. Mother underwent transsphenoidal surgery 1 year postpartum and on follow up she is under remission. Neonatal hypoadrenalism should be anticipated in maternal CS.  相似文献   
88.
Purpose: The main purpose of this study is to develop a device for the indicative measurement of intraocular pressure (IOP) of eyeball, a key cause for glaucoma. In early diagnosis and treatment of glaucoma accurate measurement of IOP is important. The methods and devices which are available for the measurement of IOP have their own limitations which cause discomfort to the patients during measurement and needs anesthesia. There is a dare need of a device for the measurement of intraocular pressure by making the contact of plunger with closed eyelid eliminating the need of anesthesia and expert ophthalmologist. Method: Additive manufacturing (AM) is an era of technical development and innovation. Developing a device for detecting glaucoma by using AM and TRIZ ‘The theory of inventive problem solving’ (A Collaborative approach) can overcome the disadvantages that classic tonometer have. The field of Ophthalmology will be experiencing a paradigm shift towards the use of collaborative approach of TRIZ with AM. The developed new device was tested on 40 patient’s eye at Government Hospital Bhandara, (M. S.), India. The results of new device were cross verified by expert clinicians using calibrated Schiotz’s tonometer and digital palpation technique. Result: The developed new device was tested on patient’s eye through eyelid and results were compared with calibrated Schiotz’s tonometer. The results from the new device were found in good agreement with results from Schiotz’s tonometer with the average error of 0.033 ± 0.18 (mean ± SD) mm of Hg and mean relative error was -0.0018 ±0.0096 (mean ± SD). Conclusion: There is a substantial need for early detection and diagnosis of glaucoma in rural and remote areas (worldwide). A new device for detection of glaucoma using AM and TRIZ was introduced in this paper and measurements by the new device were by currently well accepted Schiotz’s tonometer. The new device will help the medical practitioners in rural and remote areas for early detection of glaucoma.  相似文献   
89.
Angiogenesis is critical for tumour growth and metastasis where factors that regulate this process are potential targets for development of anti-cancer drugs. In this study, we show that the first TSR domain of the extracellular matrix protease ADAMTS5, unlike the second TSR, has anti-angiogenic activities where it inhibits endothelial cell tube formation on Matrigel, reduces cell proliferation and attachment, while promoting cell apoptosis and migration, all in a dose-dependent manner. Furthermore, it influences the architecture of endothelial cells by disrupting actin stress fibres and reducing focal adhesions, likely via suppressing RhoA activation. TSR1 of ADAMTS5 is therefore a novel anti-angiogenic peptide and could serve as a prototype for future development into anti-cancer drugs.  相似文献   
90.
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