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51.
Growth hormones (GHs) have been isolated from pituitary glands of American plaice (Hippoglossoides platessoides), a marine flatfish, using affinity and gel filtration chromatography, followed by preparative polyacrylamide gel electrophoresis (PAGE). A bioassay based on serum triiodothyronine elevation in immature rainbow trout was used to monitor biological activity. These GHs originate from two molecular mass regions, 42K and less than 33K relative molecular mass (Mr), in their native state. The 42K Mr region yielded two forms of GH, which differ in terms of quantity and net charge as evidenced by native PAGE, a major variant with a relative mobility of (Rf) 0.22 and a lesser variant with Rf 0.28. The less than 33 Mr region has a single GH species with Rf 0.22. Upon sodium dodecyl sulfate-PAGE, without reduction, both GH variants from the 42K Mr region gave Mrs of 21K, while the GH from the less than 33K Mr region was 20K Mr, typical of monomeric vertebrate GHs. The proteins composing the 42K Mr region are proposed as GH dimers since they yield 21K Mr peptides. The less than 33K Mr region contains a GH monomer (20K Mr) in its native state. An amino-terminal amino acid sequence, identical for both the 42K and the 20K Mr Rf 0.22 forms, has good homology with other complete fish GH sequences near their carboxyl-terminal regions (between amino acids 130 and 196). The GH dimers (42K Mr) predominate in the plaice pituitary, contributing 93% of the total, of which 86% gives rise to the Rf 0.22 variant.  相似文献   
52.
To assess the association between RA and chronic obstructive pulmonary disease (COPD) in a population-based case-control study. A cross-sectional analysis performed utilizing the database of Clalit Health Services, the largest healthcare provider organization in Israel. Patients over the age of 20 years who were diagnosed with RA (‘cases’) and who were treated with any anti-rheumatic drug were compared with a sample of age- and gender-matched enrollees (‘controls’) without regard for the prevalence of COPD. Data on health-related lifestyles and other comorbidities were collected. χ2, t tests, and logistic regression models were used to compare the study groups. The study included 9,039 RA cases and 15,070 controls. The proportion of COPD was significantly higher in patients with RA as compared to the control group (8.6 vs. 4.4 %, p < 0.0001, odds ratio (OR) 2.06, 95 % confidence interval (CI) 1.85–2.29). A multivariate logistic regression model demonstrated that RA was significantly associated with COPD, after controlling for confounders, including age, sex, socioeconomic status, smoking, and obesity (adjusted OR 1.98, 95 % CI 1.77–2.21, p < 0.0001). In this large data-based study, RA was found to be associated with COPD.  相似文献   
53.
The clinical spectrum of infant botulism   总被引:4,自引:0,他引:4  
Infant botulism is the systemic illness that results when spores of Clostridium botulinum germinate in the infant's intestine and then produce botulinal toxin in vivo. As with other infectious diseases, infant botulism has a spectrum of clinical severity that ranges from a mild, outpatient illness to fulminant, sudden death. Most cases reported to date have been recognized in infants so weak and hypotonic that their need for hospital care was unquestioned; yet even this group of patients displayed a wide range in severity of illness. The outpatients were initially considered to be cases of "failure to thrive," while the fulminant cases were indistinguishable at autopsy from typical instances of the sudden infant death syndrome (SIDS, crib death). This article discusses the observed spectrum of clinical severity, the management of the hospitalized patient, and the manner in which sudden death might result from production of butulinal toxin in the intestine.  相似文献   
54.
55.
Estrogens are critical hormones involved in reproduction and need to bind to estrogen receptors in target organs for biological activity. Fishes have two distinct estrogen receptor subtypes, alpha (α) and beta (β), with variable combinations of additional isoforms of each subtype dependent on the history of genome duplication within a taxon. The comparative expression patterns of estrogen receptor isoforms during the female reproductive cycle will provide important insights into the unique function and importance of each. The purpose of this study was to measure the mRNAs for the four estrogen receptor isoforms (erα1, erα2, erβ1, erβ2) in the liver and ovary of adult, female rainbow trout over the course of an annual reproductive cycle. The expression of estrogen receptor mRNA isoforms was measured by quantitative real-time RT-PCR. Several reproductive indices (gonadosomatic index, maximum oocyte diameter, plasma estradiol-17β, plasma vitellogenin, and ovulation) were also quantified for comparison and used in a correlation analysis to examine any inter-relationships. Of the four isoforms, the expression of erα1 was highest in the liver, and had a significant positive correlation with liver erβ1 expression. Liver expression of erα2 mRNA was the lowest, but showed a significant positive correlation with maximum oocyte diameter in the ovary. The pattern of the erβ isoforms in liver was one of initially elevated mRNA expression followed by a gradual decrease as reproductive development proceeded. In the ovary the erβ1 isoform had the highest mRNA expression of all estrogen receptor isoforms, at the beginning of the reproductive cycle, but then decreased afterward. Both ovarian erβ isoforms had a significant positive correlation with one another. In contrast, erα2 mRNA expression showed a high maximum level in the ovary near the end of the cycle along with a significant positive correlation with plasma estradiol-17β levels; the highest gonadosomatic indices, maximum oocyte diameter, and vitellogenin levels occurred then too.  相似文献   
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57.
ObjectiveAnemia is an independent predictor of poor prognosis in acute coronary syndrome. Endothelial progenitor cells are bone marrow-derived cells that are mobilized into the circulation in response to ischemia. The number of circulating endothelial progenitor cells increases within days of acute coronary syndrome. There is no confirmation regarding the correlation between the occurrence of anemia and the deficiency in endothelial progenitor cells in patients with acute coronary syndrome. The correlation between chronic anemia and endothelial progenitor cells in patients with acute coronary syndrome was investigated.MethodsEndothelial progenitor cells were examined in 26 patients with acute coronary syndrome. Fifteen patients had chronic nonprogressive anemia, and 11 patients had a normal blood count. Blood samples were drawn on the first day of admission and 4 to 7 days later. Mononuclear cells were separated and cultured on fibronectin-coated plates with EndoCult medium (StemCell Technologies, Vancouver, BC, Canada) for 5 days. Colony forming unit count and a migration assay were performed at each time point.ResultsBaseline colony forming unit in the non-anemic group was higher than in the anemic group (P < .0001). There was a highly significant correlation between admission hemoglobin and colony forming unit count (R = 0.83, P < .0001). Colony forming units increased in both groups on the second measurement but to a lower extent in the anemic group (P = .0004). The migration assay in the non-anemic group was higher than in the anemic group at baseline (P = .017) and 4 to 7 days later (P = .0054).ConclusionPatients with acute coronary syndrome with anemia demonstrate a reduced number of peripheral endothelial progenitor cells with impaired function, possibly representing a lower capacity for vascular healing. These phenomena may partly explain the poor prognosis observed in patients with acute coronary syndrome and anemia.  相似文献   
58.
Because information on management and outcome of AML relapse after allogeneic hematopoietic stem cell transplantation (HSCT) with reduced intensity conditioning (RIC) is scarce, a retrospective registry study was performed by the Acute Leukemia Working Party of EBMT. Among 2815 RIC transplants performed for AML in complete remission (CR) between 1999 and 2008, cumulative incidence of relapse was 32% ± 1%. Relapsed patients (263) were included into a detailed analysis of risk factors for overall survival (OS) and building of a prognostic score. CR was reinduced in 32%; remission duration after transplantation was the only prognostic factor for response (P = .003). Estimated 2-year OS from relapse was 14%, thereby resembling results of AML relapse after standard conditioning. Among variables available at the time of relapse, remission after HSCT > 5 months (hazard ratio [HR] = 0.50, 95% confidence interval [CI], 0.37-0.67, P < .001), bone marrow blasts less than 27% (HR = 0.53, 95% CI, 0.40-0.72, P < .001), and absence of acute GVHD after HSCT (HR = 0.67, 95% CI, 0.49-0.93, P = .017) were associated with better OS. Based on these factors, 3 prognostic groups could be discriminated, showing OS of 32% ± 7%, 19% ± 4%, and 4% ± 2% at 2 years (P < .0001). Long-term survival was achieved almost exclusively after successful induction of CR by cytoreductive therapy, followed either by donor lymphocyte infusion or second HSCT for consolidation.  相似文献   
59.
Strategies that increase homing to the bone marrow and engraftment efficacy of ex?vivo expended CD34(+) cells are expected to enhance their clinical utility. Here we report that nicotinamide (NAM), a form of vitamin B-3, delayed differentiation and increased engraftment efficacy of cord blood-derived human CD34(+) cells cultured with cytokines. In the presence of NAM, the fraction of CD34(+)CD38(-) cells increased and the fraction of differentiated cells (CD14(+), CD11b(+), and CD11c(+)) decreased. CD34(+) cells cultured with NAM displayed increased migration toward stromal cell derived factor-1 and homed to the bone marrow with higher efficacy, thus contributing to their increased engraftment efficacy, which was maintained in competitive transplants with noncultured competitor cells. NAM is a known potent inhibitor of several classes of ribosylase enzymes that require NAD for their activity, as well as sirtuin (SIRT1), class III NAD(+)-dependent-histone-deacetylase. We demonstrated that EX-527, a specific inhibitor of SIRT1 catalytic activity, inhibited differentiation of CD34(+) cells similar to NAM, while specific inhibitors of NAD-ribosylase enzymes did not?inhibit differentiation, suggesting that the NAM effect is SIRT1-specific. Our findings suggest?a critical function of SIRT1 in the regulation of hematopoietic stem cell activity and imply the?clinical utility of NAM for ex?vivo expansion of functional CD34(+) cells.  相似文献   
60.
BACKGROUND: Hyperthyroidism has been associated with liver function abnormalities; however, cholestasis as the presenting feature of adolescent Graves' disease has not been previously reported. PATIENT SUMMARY: The patient was a 17-year-old girl who presented with severe cholestasis and was found to have Graves' disease. She also had a positive hepatitis A immunoglobulin M antibody but her clinical course, the liver histopathology, and her mildly elevated transaminases indicated that the acute hepatitis A infection was not dominant at the time of presentation with severe cholestasis. Other causes of cholestasis, including congestive heart failure, autoimmune hepatitis, and viral infection, were excluded. Treatment with methimazole resolved the hyperthyroidism, and the cholestasis improved, as well. CONCLUSION: Severe cholestasis is a rare presenting feature of Graves' disease. With careful monitoring, methimazole can be used to treat the hyperthyroidism in the setting of cholestasis.  相似文献   
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