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991.
After the previous characterization of one trypsin gene (Try1) of the human body louse Pediculus humanus, genes encoding a second trypsin (Try2) and a chymotrypsin (Chy1) have been cloned using degenerate serine proteinase primers and 5- and 3-RACE, and sequenced. The deduced 259 and 267 amino acid sequences of Try2 and Chy1 show an identity of 33%–40% to trypsinogens and chymotrypsinogens of other insects. Considering previously published partial sequences, P. humanus possesses at least one Try1 gene, five variants/isoforms of Try2 and six variants/isoforms of Chy1. The genomic DNA of Try2 contains three introns and Chy1 contains five introns. Using whole mount in situ hybridization, gene expression of Try1, Try2 and Chy1 has been localized not only in the distensible anterior region of the midgut of lice but sometimes also in the area following the distensible region. The Try2 gene was always expressed at much lower levels than Try1 or Chy1. This lower expression, the constitutive expression of Try1 and Chy1 at 1, 2, 6, 12 and 24 h after feeding of adults and the regional differences have been verified in quantitative real-time PCR.  相似文献   
992.
Pathomorphological examination of trephine biopsies of the bone marrow (BM) represents a standard method for the diagnosis and staging of hematologic neoplasms and other disorders involving the BM. The increasing knowledge about the genetic basis and biology of hematologic neoplasms, as well as the recently proposed WHO classification system, provide the framework for an accurate diagnosis. Although conventional morphology remains the gold standard for paraffin-embedded BM trephines, immunohistochemical stainings have become an integral part of the diagnostic workup. Antibodies suitable for paraffin sections are generally applicable to BM trephines, but modifications of staining protocols may be necessary due to the alternative fixatives and decalcification procedures used for BM biopsies. The indications for immunostainings range from confirmation and classification of lymphoma involvement, subclassification of acute leukemias, and estimating blast counts in myelodysplastic and myeloproliferative syndromes to characterization of BM involvement in nonhematologic neoplasms. Although subtyping of NHL in the BM is more difficult from the point of morphology, classification of the entities that frequently involve the BM, especially the small B-cell lymphomas, can easily be achieved with the help of immunohistochemistry. In this review, we try to summarize the current state of the art in BM immunohistochemistry for the diagnosis of hematologic disorders. Moreover, diagnostic algorithms and useful antibody panels are proposed for a rational and cost-effective approach.  相似文献   
993.
The present study examined the association of the Tyrosine hydroxylase Val-81-Met polymorphism with alcohol dependence. One hundred and fifty-nine patients in a psychiatric unit with alcohol dependence were genotyped as well as 92 healthy volunteers. The Val allele was more frequent in patients with alcohol dependence (69.5%) than in controls (62.5%). This effect was largely due to the association with early-onset alcoholism (77.8%), whereas no difference was noted between late-onset patients and controls. Our results suggest a role for tyrosine hydroxylase in early-onset alcoholism.  相似文献   
994.
Primary extramedullary plasmacytomas are infrequent, typically solitary, plasma cell neoplasms that generally pursue an indolent clinical course but may, rarely, convert to multiple myeloma. Phenotypic differences between these two entities are not well defined. Twenty-eight cases of primary extramedullary plasmacytoma and 26 cases of both medullary (n = 17) and extramedullary (n = 9) multiple myeloma were analysed for the expression of proteins known to play a role in the biology of multiple myeloma. Immunohistochemistry was performed on paraffin wax sections using antibodies against cyclin D1, Bcl-2, Bcl-xL, p27, p21, p53, MIB1, CD20, and CD56. Twenty-three extramedullary plasmacytomas were localized in the upper aerodigestive tract, four in the lymph nodes, and one in the testis. There was a strong male predominance (M : F = 6 : 1). None of the patients died from the disease or progressed to multiple myeloma (mean follow-up 50 months). Nine patients developed local relapse and one patient's tumour evolved into a B-cell non-Hodgkin's lymphoma. In contrast to both intra- and extra-medullary multiple myeloma, extramedullary plasmacytoma showed absence of cyclin D1 (p < 0.001) and infrequent expression of CD56 (p < 0.001). Furthermore, extramedullary plasmacytomas were characterized by weaker staining for Bcl-2 protein and rare overexpression of p21 and p53. In comparison to extramedullary multiple myeloma, extramedullary plasmacytoma showed a more mature morphology and lower proliferation indices (p = 0.008). There was no association between the phenotypic parameters investigated and clinical outcome in extramedullary plasmacytoma. In summary, extramedullary plasmacytoma and multiple myeloma show significant immunophenotypic differences, some of which may be of both diagnostic utility and biological relevance.  相似文献   
995.
We report on a patient with long-standing severe autonomic failure that affected his sympathetic and parasympathetic nervous systems. Antibodies against the ganglionic acetylcholine receptors were detected in the serum. Removal of the antibodies by means of plasma exchange resulted in a dramatic clinical improvement.  相似文献   
996.
Exaggerated procoagulant responses to acute mental stress may contribute to coronary thrombosis, and continuing low-grade systemic coagulation activation may link negative affect with the development of coronary artery disease. We investigated whether negative and positive affect and perceived social support would moderate stress procoagulant reactivity. Psychological functioning, exhaustion, negative affectivity, depression, anxiety, worrying, vigor, and social support were assessed in 27 apparently healthy men (mean age 47 +/- 8 years) who underwent the 13-min Trier Social Stress Test combining preparation, speech, and mental arithmetic. Plasma levels of von Willebrand factor antigen (VWF:Ag), fibrinogen, factor VII clotting activity (FVII:C), FVIII:C, FXII:C, and D-dimer were measured immediately before and after stress. Acute stress elicited significant increases in hemodynamic, cortisol, and coagulant activity (p values < 0.05). VWF:Ag reactivity showed inverse relationships with exhaustion (r = -0.63, p < 0.001), negative affectivity (r = -0.53, p = 0.005), and worrying (r = -0.53, p = 0.005). Exhaustion and negative affectivity emerged as independent predictors of VWF:Ag reactivity explaining 54% of its variance. Fibrinogen reactivity showed inverse relationships with negative affectivity (r = -0.59, p = 0.002) and anxiety (r = -0.54, p = 0.005); negative affectivity emerged as an independent predictor of fibrinogen reactivity explaining 35% of its variance. Psychological functioning and FVII:C reactivity were also correlated (r = -0.52, p = 0.006). Whereas FVIII:C reactivity correlated positively with vigorous mood (r = 0.48, p = 0.012), positive associations between social support and procoagulant reactivity did not reach significance. Negative affect was associated with attenuated procoagulant reactivity to stress and the opposite was observed for positive affect. Negative affect is not likely to enhance the acute procoagulant stress response in healthy men.  相似文献   
997.
Alzheimer's disease (AD) is the most common cause of dementia. It is characterized by beta-amyloid (A beta) plaques, neurofibrillary tangles and the degeneration of specifically vulnerable brain neurons. We observed high expression of the cholesterol 25-hydroxylase (CH25H) gene in specifically vulnerable brain regions of AD patients. CH25H maps to a region within 10q23 that has been previously linked to sporadic AD. Sequencing of the 5' region of CH25H revealed three common haplotypes, CH25Hchi2, CH25Hchi3 and CH25Hchi4; CSF levels of the cholesterol precursor lathosterol were higher in carriers of the CH25Hchi4 haplotype. In 1,282 patients with AD and 1,312 healthy control subjects from five independent populations, a common variation in the vicinity of CH25H was significantly associated with the risk for sporadic AD (p = 0.006). Quantitative neuropathology of brains from elderly non-demented subjects showed brain A beta deposits in carriers of CH25Hchi4 and CH25Hchi3 haplotypes, whereas no A beta deposits were present in CH25Hchi2 carriers. Together, these results are compatible with a role of CH25Hchi4 as a putative susceptibility factor for sporadic AD; they may explain part of the linkage of chromosome 10 markers with sporadic AD, and they suggest the possibility that CH25H polymorphisms are associated with different rates of brain A beta deposition.  相似文献   
998.
Deutschmann A  Mache CJ  Bodo K  Zebedin D  Ring E 《Pediatrics》2005,116(5):1231-1233
We describe the case of an 18-year-old girl with chronic recurrent multifocal osteomyelitis (CRMO) over a period of 10 years. She had suffered predominantly from very painful recurrent swelling of her cheeks. Various therapeutic regimens including nonsteroidal antiinflammatory drugs and steroids had shown only a partial or temporary response. Because tumor necrosis factor-alpha-blocking agents have been successfully applied in Crohn's-associated CRMO and the related SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome, tumor necrosis factor-alpha-blocking therapy with infliximab was initiated. Thereafter, apart from 1 mild episode, no additional recurrences were observed during 21 months of follow-up. Infliximab was well tolerated, and steroids were tapered off. Our observation indicates that infliximab may be an effective therapeutic option in CRMO.  相似文献   
999.
1000.
PURPOSE: This analysis evaluates whether adjuvant chemotherapy can be recommended for high-risk, surgically-resected, adult-type non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) within the new European Pediatric Soft Tissue Sarcoma Study Group (EpSSG) protocol. The Italian and German Cooperative Groups reviewed their data-bases, analyzing patients classified as group I-II, with high-grade tumor (G3) larger than 5 cm in size. METHODS: The analysis included 36 patients, and compared the clinical features and outcome of the group of 21 patients who received chemotherapy versus the group of 15 patients treated with local therapies only. RESULTS: For the series as a whole, 5-year event-free survival (EFS), metastasis-free survival (MFS), and overall survival (OS) were 26.2%, 34.0%, and 37.5%, respectively. In patients treated with chemotherapy, MFS and OS were 49.5% and 41.5% (median time to relapse: 13 months). In patients who did not receive chemotherapy, MFS and OS were 0% and 23.8% (median time to relapse: 3 months). CONCLUSION: The role of adjuvant chemotherapy in NRSTS is still uncertain, however, the current retrospective analysis showed that: (1) despite the globally good prognosis of grossly-resected cases, patients with G3 and large-size have a high-risk of metastatic spread, and (2) MFS appears to be better in patients who had chemotherapy. Based in part on these results, and in accordance with recent suggestions coming from the literature on adult sarcomas, the EpSSG NRSTS protocol will recommend adjuvant chemotherapy in high-risk surgically-resected patients.  相似文献   
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