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21.
Seasonal variations of environmental factors, such as temperature and salinity, require metabolic acclimatization in sedentary benthic fauna distributed over a wide geographical range. The soft-shell clam Mya arenaria inhabits the coastal waters of the North Atlantic including North America and Europe. In Europe, M. arenaria populations are distributed from Iceland to the Mediterranean Sea, including the North Sea, the Baltic Sea and the Black Sea. Seasonal changes in physiological parameters (gonad index, condition index, biochemical composition and respiration rate) of M. arenaria from the Baltic Sea (the Gulf of Gdańsk, Poland), and the North Sea (Versee Meer, the Netherlands) were studied. The sex ratio of both populations did not differ from 1:1 and the seasonal gonad index was higher in the Baltic population. The average condition index changed seasonally at both studied sites, and was also higher in the Baltic population (except the autumn) compared to the North Sea. In both studied populations, the content of proteins, lipids and carbohydrates in the soft tissue followed the seasonal variations, and it was higher in the Baltic population. The respiration rate was lower in the Baltic population, and seasonal changes in the respiration rate seem to be correlated with changes in the water temperature. Based on the results obtained in the present study, we suggest that Mya arenaria is characterized by a large phenotypic plasticity and differences in the observed physiological traits are due to acclimatization to ambient environmental conditions.  相似文献   
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Background

L-asparaginase (L-asp) remains one of the key components of acute lymphoblastic leukemia therapy. Immune reactions to the drug are associated with its diminished activity. The aim of the study was to determine the level of IgM, IgG and IgE-class anti-L-asp antibodies during the induction and reinduction phases of acute lymphoblastic leukemia therapy and their influence on L-asp activity.

Methods

The study group comprised 65 patients treated for acute lymphoblastic leukemia in one pediatric oncology center. L-asp antibodies were assessed using ELISA at the end of the induction and reinduction phases. L-asp activity was assessed prior to each drug administration by colorimetry.

Results

At the end of the first exposure to L-asp antibodies were detected in 35 patients (54%). In the reinduction phase of the treatment anti-L-asp antibodies were found in 38/55 patients (69%). In the induction phase patients with inadequate L-asp activity had higher IgM concentrations (median 5.88 versus 2.81?μg/mL, p?=?0.03). In the reinduction phase IgG and IgM levels correlated inversely with L-asp activity. Patients with L-asp allergy had higher levels of IgG (median 61.6 versus 18.36 μg/mL, p?=?0.01), whereas higher IgE levels were noted in the group of patients with inadequate drug activity (median 0.91 versus 0.64 μg/mL, p?=?0.03).

Conclusions

Subsequent exposure to L-asp in the treatment of acute lymphoblastic leukemia was associated with the increase of anti-L-asp antibodies in all studied classes. However, the changes observed in specific classes of antibodies were not distinctive for L-asp hypersensitivity or inactivation, suggesting that the mechanism is more complex.  相似文献   
24.
The aim of this study was to analyze the prevalence of Staphylococcus aureus in the tonsils of children subjected tonsillectomy due to recurrent tonsilitis and to determine the spa types of the pathogens, carriage of virulence genes and antimicrobial resistance profiles. The study included 73 tonsillectomized children. Bacteria, including S. aureus were isolated from tonsillar surface prior to tonsillectomy, recovered from tonsillar core at the time of the surgery, and from posterior pharynx 2–4 weeks after the procedure. Staphylococcus aureus isolates were compared by spa typing, tested for antimicrobial susceptibility and for the presence of superantigenic toxin genes (sea-seu, eta, etb, tst, lukS/lukF-PV) by multiplex polymerase chain reaction. Seventy-three patients (mean 7.1 ± 4.1 years, 61.6% male) were assessed. The most commonly isolated bacteria were S. aureus. The largest proportion of staphylococcal isolates originated from tonsillar core (63%), followed by tonsillar surface (45.1%) and posterior pharynx in tonsillectomized children (18.2%, p = 0.007). Five (6.3%) isolates were identified as MRSA (mecA-positive). Up to 67.5% of the isolates synthesized penicillinases (blaZ-positive isolates), and 8.8% displayed MLSB resistance. The superantigenic toxin genes were detected in more than half of examined isolates (56.3%). spa types t091, t084, and t002, and clonal complexes (CCs) CC7, CC45, and CC30 turned out to be most common. Staphylococcus aureus associated with RT in children showed pathogenicity potential and considerable genetic diversity, and no clones were found to be specific for this condition although further studies are needed.  相似文献   
25.
Background and aimsCholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) are crucial proteins in reverse cholesterol transport. There are insufficient data on regulating these proteins by insulin therapy in type 1 diabetes mellitus (T1DM). We aimed to assess prospectively the impact of insulin therapy initiation on transfer proteins serum levels in adults with newly diagnosed T1DM.Methods and results57 adults with newly diagnosed T1DM were enrolled in the InLipoDiab1 Study. All participants were treated with subcutaneous insulin in the model of intensive insulin therapy since the diagnosis of diabetes. Serum PLTP and CETP concentrations were measured at diagnosis, after three weeks, six months, and after one year of insulin treatment, using the immunoenzymatic method ELISA.A significant decrease in PLTP and CETP concentrations were demonstrated during twelve months of insulin therapy in newly diagnosed T1DM. The dynamics of changes in the level of these proteins varied depending on the occurrence of remission after a year of the disease. In the group without remission, a significant decrease in PLTP and CETP levels appeared after six months of follow-up. The remission group was characterized by a decrease in proteins concentration only after one year of treatment. In the non-remission group, significant negative correlations were found between the daily dose of insulin and levels of PLTP and CETP.ConclusionExogenous insulin is an inhibitor of lipid transfer proteins involved in high-density lipoprotein cholesterol metabolism in the first year of treatment.  相似文献   
26.
Background: Popular views of addictive substances and behaviors constitute an important research topic because these views have an impact upon the functioning of treatment systems and societal responses to substance use disorders. Methods: The analysis is based on a random sample of N = 1000 telephone interviews collected in Poland in 2013. Questionnaire measures targeted such issues as the perceived risks of addictions and beliefs about potential recovery from various types of addictions. Results: First, a coherent view of the addiction potential of various addictive substances and/or behaviors emerges, distinguishing licit drugs and types of behavior from illicit drugs. Second, treatment optimism proves to be quite high independent of the type of addictive behavior, while chances of recovery without treatment are considered less likely. Third, chances for assisted change (change with treatment) and self-change are considered largely independent of perceived addiction-related risks and are not perceived as contradictory. Conclusions: The results point to the persistence of the disease model of addiction in Poland, placing responsibility for addiction on the individual and pairing it with the expectation of undergoing specialized treatment. This individualistic approach was applied as a framework for addiction problems in the 1950s to deflect from the shortcomings of the ‘‘new socialist society.’’ Neo-liberal market reform and socioeconomic changes have provided reinforcement for this individualistic framework.  相似文献   
27.
Blood samples of 50 patients diagnosed for paroxysmal nocturnal haemoglobinuria (PNH) were examined using FLAER screening test for the detection of PNH clone. The results were compared with routine testing using monoclonal antibodies detecting CD59 and CD66b antigens on neutrophils and CD59 on erythrocytes. Assay sensitivity (≥ 0.1%) and PNH clone size analysed using FLAER and anti-CD66b antibodies was fully consistent (R2 = 0.9991) and higher than with anti-CD59 antibodies. Preliminary results indicate that for diagnosis of PNH the FLAER based test is quick, reliable and cost-effective. It might seem that the conventional screening methods could therefore be abandoned. It was found however, that in some cases of abnormal granulocyte population, additional studies should be performed using multiparameter flow cytometry blood cell analysis.  相似文献   
28.
Respiratory morbidity in Inuit children is high. However, little is know regarding lung function measures in this population. The forced expiratory volumes in one second (FEV(1)) and forced vital capacity (FVC) in 888 Greenlandic Inuits (N=888) and Danes (N=477) aged 6-18 years were compared. Furthermore, associations between level of lung function and atopy and lifestyle factors were estimated in Greenlanders. The effect of height on FEV(1) and FVC was significantly different in Greenlanders and Danes, this difference in lung function increased with increasing height, and could not be explained by differences in age weight and BMI. Thus, Greenlanders taller than 130 cm had up to 300-400 ml higher FEV(1) and FVC compared with Danes of the same height. Among Greenlanders, those living in settlements had the highest levels of both FEV(1) and FVC. Greenlanders had elevated levels of FEV(1) and FVC compared with Danes. The Inuit having a shorter limb length in relation to trunk height may account for these differences. However, our finding that Greenlanders living in settlements had the highest lung function level also suggests a possible role of factors in the traditional Greenlandic lifestyle.  相似文献   
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30.
Melanotic Schwannomas (MS) are rare tumors that share histological features with melanocytic tumors and schwannomas. However, their genetics are poorly understood. To elucidate the genetic characteristics of MS, we performed genome‐wide studies in a series of cases. Twelve MS cases were available for the study. Genomic DNAs extracted from formalin‐fixed paraffin embedded tumor tissues were subjected to copy number (CN) and allelic imbalance (AI) analysis by Single Nucleotide Polymorphism (SNP)‐array and screened for mutations in coding exons of 341 key cancer‐associated genes using a hybrid capture‐based next‐generation sequencing (NGS) assay. Sanger sequencing was used to further verify recurrent mutations detected by NGS study. SNP‐array analysis revealed remarkably stereotypic chromosomal abnormalities in MS. Hypodiploidy was common, typically involving monosomies of chromosomes 1, 2, and 17. All 12 samples showed mutations in PRKAR1A gene, including 2 cases with 2 mutations each. The 14 mutations were scattered across PRKAR1A, and most were inactivating mutations. AI on 17q, presenting as loss of heterozygosity with or without CN losses, combined with a PRKAR1A mutation was observed in 9/12 MS cases. The remaining 3 cases included the two samples harboring two mutations in PRKAR1A. MS exhibits a stereotypic pattern of chromosomal losses. In contrast, melanomas are typically characterized by the presence of multiple CN aberrations, without demonstrable differences in the frequency of losses and gains. Inactivation of both alleles of PRKAR1A by “two hits” observed in almost all cases underscores the central role of PRKAR1A in the pathogenesis of this neoplasm. © 2015 Wiley Periodicals, Inc.  相似文献   
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