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排序方式: 共有2969条查询结果,搜索用时 12 毫秒
121.
Zohreh Talebi-Yazdabadi Neda Jahanbakhsh Kianoush Dormiani Mahboobeh Forouzanfar Liana Lachinani Dina Zohrabi Marziyeh Tavalaee Mohammad Hossein Nasr-Esfahani 《Andrologia》2021,53(10):e14187
MUSASHI (MSI) family plays the main role in the spermatogenesis process. The purpose of this study was the assessment of sperm MSI1 and MSI2, and sperm functional tests in infertile men (n = 30) with varicocele and fertile men (n = 30). Furthermore, MSI1 and MSI2 proteins were assessed in testicular tissue of azoospermic men (n = 9) as well as epididymal spermatozoa and testis of mice. Expression of MSI1 and MSI2 was assessed at RNA and protein levels in human spermatozoa. Sperm concentration and motility were significantly lower, while abnormal sperm morphology, lipid peroxidation, DNA fragmentation and protamine deficiency were significantly higher in men with varicocele compared to fertile individuals. Any significant difference was not observed in the expression of MSI1 and MSI2 mRNA between the two groups. Unlike MSI1 protein that was not detectable in humans, the relative expression of MSI2 protein was similar in varicocele and fertile individuals. The expression level of both Msi1 and Msi2 proteins was also observable in mouse spermatozoa. No significant relationship was observed between sperm functional parameters with expression of these genes. The data of this study demonstrated that although MSI1 and MSI2 play important roles during spermatogenesis, their relative expression in spermatozoa was not affected by varicocele. 相似文献
122.
Difficulty in segregating graft-versus-tumor effect (GvT) from graft-versus-host disease (GvHD) remains a major limitation of allogeneic stem cell transplantation (Allo SCT). Naturally occurring regulatory T cells have been suggested to suppress alloreactive T cells involved in GvHD; however, their non-selective suppressive effect raises concern regarding probable attenuation of the GvT effect. Recent studies suggested inducible CD8 (iCD8) cells to be useful in suppressing autoimmune reactions, although their function in the Allo SCT setting has not been fully explored. The current study assessed in-vitro the properties of iCD8 T cells, generated in response to allogeneic dendritic cells (DCs), imitating the Allo SCT conditions. CD25? peripheral blood mononuclear cells (PBMCs) were stimulated with allogeneic DCs in mixed lymphocyte culture (MLC). The resultant iCD8+CD25+ population was isolated and assessed for phenotypic markers, cytokine expression profile, cell proliferation, inhibitory capacity and anti-viral response. The generated CD8+CD25+FOXP3+ T cells selectively inhibited the primary allogeneic response, without attenuating T cell response against other stimuli, such as mitogens or a cytomegalovirus (CMV) recall antigen. In conclusion, iCD8+CD25+ cells suppress allogeneic stimulation, while maintaining the capacity to respond to infectious pathogens. These cells could be potentially efficient in the Allo SCT setting, where GvHD prevention is required. 相似文献
123.
124.
Osama M. Assad Dina A. Aly Labib Laila Ahmed Rashed 《Egyptian Journal of Anaesthesia》2018,34(1):33-39
Background
Myocardial ischaemia/reperfusion (MI/R) may induce renal damage. Our aim was to investigate the effects of dexmedetomidine (DEX) administration at two different timings either before or after ischaemia on renal damage induced by MI/R.Methods
MI/R injury was induced in a rat model. we ligated the left anterior descending coronary artery for 30?min (ischaemic period), then reperfusion occurred for 2?h (reperfusion period). A single dose of DEX (100?µg/kg) was given intraperitoneally, either 30?min before myocardial ischaemia or 5?min after reperfusion. With the end of reperfusion period, rats were sacrificed, then we collected the blood and removed both kidneys quickly for biochemical and histopathological analysis.Results
MI/R caused an elevation in serum urea and creatinine, significant elevation in malondialdehyde (MDA) release and decrease in superoxide dismutase (SOD) activity in the rat kidney. There were also higher levels of serum tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Treatment with dexmedetomidine, 30?min before induction of myocardial ischaemia, succeeded to improve all the tested parameters. The valuable changes in these biochemical parameters were linked with similar enhancement in the histopathological appearance of the kidney. Meanwhile, DEX given 5?min after reperfusion improved serum urea and creatinine only.Conclusion
These findings imply that MI/R plays a fundamental role in kidney damage through increased production of oxygen radicals or deficiency in antioxidants, and DEX given before ischaemia exerts reno-protective effects probably by its radical scavenging antioxidant activity and anti-inflammatory mechanism. 相似文献125.
Orbital pseudotumor, also known as idiopathic orbital inflammatory syndrome (IOIS), may have protean clinical manifestations. Some presentations of IOIS may mimic common conditions such as orbital cellulitis and optic neuritis. IOIS should be considered a diagnosis of exclusion, with evaluation directed toward eliminating other causes of orbital disease. Orbital magnetic resonance imaging is the single most important diagnostic test, but serologic studies are necessary to exclude a systemic cause. Biopsy is usually not performed at presentation, as the risk of producing damage to vital structures within the orbit outweighs the benefits. Patients with multiple recurrences, or those unresponsive to therapy, should have biopsy samples taken. Corticosteroids are the mainstay of therapy and are administered for several months to ensure remission. Radiotherapy may be used in patients who fail to respond to steroids or who have a rapidly progressive course. For those patients who are refractory to both corticosteroids and radiotherapy, anecdotal reports have suggested the use of chemotherapeutic agents such as cyclophosphamide, methotrexate, and cyclosporine. 相似文献
126.
Goldstein S Samuni A Aronovitch Y Godinger D Russo A Mitchell JB 《Chemical research in toxicology》2002,15(5):686-691
The toxicity of paraquat (PQ2+) is attributed to intracellularly formed PQ*+, O(2)*-, H(2)O(2), and secondary.OH radicals generated through Fenton-like reactions. Yet, no antidote for PQ2+ toxicity in human has been found also due to poor cell permeability of many common antioxidants that remove toxic species predominantly extracellularly. Cell-permeable nitroxides, which scavenge xenobiotic-derived deleterious radicals and detoxify redox-active metal ions, would be expected to ameliorate PQ2+ toxicity. We have studied using pulse radiolysis the kinetics of the reactions of 2,2,6,6-tetramethyl-piperidinoxyl (TPO) and 4-OH-TPO with PQ*+ and CuIIL(2) (L = 1,10-phenanthroline, 2,2'-bipyridyl) in the absence and presence of DNA. We found that the rate constant for the reaction of PQ*+ with the nitroxides is about 4 orders of magnitude lower than that with O(2). In addition, the rate of the reaction of the nitroxides with CuIL(2) decreases as [DNA] increases, which suggests that nitroxides react significantly slower with bound metal ions. These results explain the failure of 4-OH-TPO to protect bacterial and mammalian cells from PQ2+ toxicity under air. In contrast, the rate of the reaction of PQ*+ with CuIIL(2) was unaffected by DNA. Furthermore, copper toxicity has been attributed mainly to CuI and was observed predominantly for cells subjected to anoxic conditions. It implied that nitroxides would be effective protectants if PQ2+ induces toxicity also under anoxia. Surprisingly, we found that PQ2+ toxicity under anoxia was even greater than that under air, and under these conditions 4-OH-TPO protected the cells from PQ. These results indicate that the mechanism underlying the anoxic toxicity of PQ2+ differs from that operating in the presence of oxygen, and that reduced transition metal ions are most probably the species responsible for PQ2+ anoxic toxicity. 相似文献
127.
An ecological model of maternal substance abuse and child neglect: issues, analyses, and recommendations 总被引:1,自引:0,他引:1
This study examined an ecological model of maternal substance abuse and child neglect. Data are presented that identified an interplay among family history, interpersonal risk factors, current family functioning, and community networks in examinations of child neglect in a sample of substance-abusing women entering treatment. 相似文献
128.
Stratford JA LoGiudice D Flicker L Cook R Waltrowicz W Ames D 《The Australian and New Zealand journal of psychiatry》2003,37(3):319-326
OBJECTIVE: To report 9 years' experience of an Australian memory clinic using the -Cambridge Mental Disorders in the Elderly Examination (CAMDEX) assessment schedule, summarizing patient demographics, diagnoses at presentation and the utility of four instruments used in distinguishing patients with and without dementia. METHODS: All patients seen at the clinic between December 1989 and September 1998 were assessed using the CAMDEX. Diagnoses were determined according to criteria of the International Classification of Diseases, tenth edition (ICD-10). RESULTS: The mean age of 577 patients seen was 72.9 years and 60.8% were female. Over 40% fulfilled ICD-10 diagnostic criteria for dementia in Alzheimer's disease. A further 24% had another dementing illness. Only 28 patients were "normal". There was no significant difference in the ability of the 107-item Cambridge cognitive examination, the 30-item mini-mental state examination, the 10-item abbreviated mental test score and the 26-item informant questionnaire on cognitive decline in the elderly to differentiate dementia patients from those who were normal or had functional psychiatric disorders. The four cognitive screening tools had high correlations with one another (r = - 0.57 to 0.93). CONCLUSION: Patient demographics and diagnoses were similar to those found in other clinics. Most people who attended the memory clinic had significant cognitive or psychiatric disorders. 相似文献
129.
Dina R Hirshfeld-Becker Joseph Biederman Sara Calltharp Eliza D Rosenbaum Stephen V Faraone Jerrold F Rosenbaum 《Neuropsychopharmacology》2003,53(11):985-999
Attention has been devoted over the past two decades to the identification of temperamental risk factors for child psychopathology. These qualities, evident in toddlerhood or earlier, have the advantage of being measurable in standardized laboratory observations well before children reach the age of onset or diagnosis of psychiatric disorders. Our group's programmatic research over the past 15 years, and that of others, has provided evidence linking "behavioral inhibition to the unfamiliar" in toddlerhood or early childhood with later social anxiety disorder. In addition, recent results by our group have suggested that "behavioral disinhibition" in early childhood, measured by the same laboratory methods, may be linked with later disruptive behavior and comorbid mood disorders. In this article, we discuss our approach to the study of temperamental precursors to disorders in high-risk children, summarize the literature linking behavioral inhibition and disinhibition to later psychopathology, and suggest directions to take in applying this methodology to the search for temperamental precursors to pediatric bipolar disorder. 相似文献
130.
Vuillaume I Devos D Schraen-Maschke S Dina C Lemainque A Vasseur F Bocquillon G Devos P Kocinski C Marzys C Destée A Sablonnière B 《Annals of neurology》2002,52(5):666-670
We investigated a French family with a new type of autosomal dominant spinocerebellar ataxia that was excluded from all previously identified genes and loci. The patients exhibited a slowly progressive gait and limb ataxia variably associated with akinesia, rigidity, tremor, and hyporeflexia. A mild cognitive impairment also was observed in some cases. We performed a genomewide search and found significant evidence for linkage to chromosome 7p21.3-p15.1. Analysis of key recombinants and haplotype reconstruction traced this novel spinocerebellar ataxia locus to a 24cM interval flanked by D7S2464 and D7S516. 相似文献