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21.
Several histological variants of colorectal carcinoma have been reported, some of them bearing prognostic significance, others only incidental findings showing unusual morphological features. The current report was aimed to describe the histological, immunohistochemical and ultrastructural features of an oncocytic adenocarcinoma of the rectum occurring in a 66-year-old woman. Histologically, it was a moderately differentiated adenocarcinoma composed by glandular structures lined by eosinophilic cells. The latter showed abundant granular cytoplasm and large nuclei with prominent nucleoli. Several glandular structures contained intraluminal, basophilic and non-birifrangent microcalcifications. The tumour cells displayed consistent anti-mitochondrial antigen, carcinoembryonic antigen, p53, CDX2 and cytokeratin 20 immunoreactivity. Ultrastructurally, more than 80% of the cytoplasmic area was occupied by abnormal mitochondria, while exocrine or endocrine granules were undetectable. The tumour infiltrated the intestinal wall through the subserosal tissue, but lymph node or distant metastases were absent. The patient is disease free 22 months after surgery. Based on the above features, this case could be appropriately named oncocytic adenocarcinoma with intraluminal microcalcifications. Like gastric neoplasms showing similar morphologic features, this tumour might have a better prognosis, and the presence of microcalcifcations could help its proper recognition at a pre-operative stage.  相似文献   
22.
INTRODUCTION: Osteosarcoma is a malignant bone neoplasm with an usually high metastatic potential. Besides the common metastatic sites such as lungs, bone, and pleura, metastases to unusual sites such as liver, brain and regional lymph nodes have also been reported with increasing frequency; among them, gastrointestinal metastases represent an extraordinarily rare event in the natural history of this neoplasia. MATERIALS AND METHODS: We describe a case of a 27 year old man, who was diagnosed with a grade IV osteoblastic osteosarcoma of the left tibia and submitted to 5 courses of pre-surgical chemotherapy; later he underwent tibial resection with implantation of a prosthesis, followed by 2 further courses of adjuvant chemotherapy. Five years after the patient presented with melena and acute anemia; during endoscopic examination, a large bleeding duodenal polyp was found, so a surgical resection of the gastric antrum, duodenum, head of the pancreas, main bile ducts and gallbladder was performed. The surgical specimen was formalin fixed and paraffin embedded, and sections obtained by the blocks were stained with haematoxylin-eosin; immunohistochemical and ultrastructural analysis were performed. RESULTS: Microscopically, the tumor mass showed a mostly fasciculated architecture, composed of spindle and epithelioid cells in a scarce fibromyxoid stroma, featuring large areas of coagulative necrosis and small foci of sclerohyalinosis. Tumor cells featured large vesciculous nuclei, with a few prominent nucleoli; no foci of osteoid matrix were detectable. The ultrastructural analysis revealed small calcified electron-dense depots both in the perinuclear cytoplasm and in the extracellular collagen matrix compatible with an "early osteoid formation". Due to alteration of the natural history of the tumor induced by multiagent chemotherapy, the rate of metastases of osteosarcoma to unusual sites has been increasing. We report the 9th case of a gastrointestinal metastasis of osteosarcoma reported thus far, and only the second one arising in the duodenum. Both the histological features and the immunohistochemical findings were not suggestive for osteosarcoma metastases because the tumor appeared dedifferentiated; in our case the combination of electron microscopy and clinical history played a pivotal role to establish the final diagnosis.  相似文献   
23.
OBJECTIVE: To study the seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus type 8 (KSHV/HHV-8) in 779 Italian blood donors. STUDY DESIGN/METHODS: Sera were tested for antibodies to a latency-associated nuclear antigen (LANA) and a capsid related protein encoded by ORF65. RESULTS: Among all Italian donors, 17.7% and 18.7% had antibodies to LANA and ORF65 protein, respectively, and 24.1% had antibodies to at least one antigen. KSHV/HHV-8 seroprevalence was higher in the Po valley and in Sardinia than close to the sub-Alpine Veneto region, Tuscany, or Apulia. KSHV/HHV-8 seroprevalence was almost equally distributed between men and women but increased in the older age groups. CONCLUSIONS: The regional differences and age distribution in seroprevalence agree partially with the incidence of classic KS in Italy. The rarity of classic KS in KSHV/HHV-8-infected subjects and the equal gender distribution of seroprevalence suggest that other cofactors may contribute to KS development in human immunodeficiency virus type 1 (HIV-1)-uninfected individuals.  相似文献   
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25.
IgA deficiency (IgA-D) represents the most common immunodeficiency syndrome of infancy. In most cases IgA-D represents an isolated immunological disorder, while sometimes it is associated with IgG subclass deficiency or with the presence of autoantibodies. We investigated the pattern of association of IgA-D with DRB1 and DQB1 loci of the HLA region by DNA molecular typing, which allows the identification of previously serologically undefined specificities. We also compared the gene frequency of DRB1 and DQB1 allelic variants between IgA-D subjects with or without serum autoantibodies. Our results indicate that the gene frequency of the DRB1*0102 subtype and of the DRBP0102, DQB1*0501 haplotype is significantly higher in IgA-D than in the general population. Furthermore, the IgA-D subjects with autoantibodies showed a positive association with DR4 and DR13 subtypes, thus supporting the hypothesis that genetic factors are also involved in the association between IgA-D and autoantibodies.  相似文献   
26.
It is still unclear whether i.v. immunoglobulins (Ig) can facilitate the reproductive prognosis of women who have suffered recurrent pregnancy loss. We report the results of a multicentre placebo- controlled study on the effect of Ig administration on pregnancy outcome in 46 women who had suffered at least three recurrent miscarriages. All were screened to exclude chromosomal or Mullerian abnormalities, the presence of antinuclear antibodies, lupus anticoagulant (LA) or elevated titres of anticardiolipin antibodies which may have revealed an underlying autoimmune problem. To avoid a selection bias towards ongoing pregnancies, i.v. Ig or placebo were administered between weeks 5 and 7 of gestation for 2 consecutive days as soon as each woman knew she was pregnant and before embryonic heart activity could be detected. A further infusion was administered at week 8 when ultrasonography confirmed an ongoing embryonic development. In all, 68% of the women who received Ig went to term versus 79% of those who received a placebo (not significant), with no significant differences in the pregnancy course or the perinatal outcome. These results suggest either that women with recurrent miscarriages who have no recognized cause of pregnancy loss have a good reproductive prognosis without any treatment or that the emotional care associated with the administration of a placebo can indirectly facilitate the progression of pregnancy.   相似文献   
27.
Polymorphonuclear leukocytes (PMN) are known to be activated by several lymphokines and can be induced to release lysosomal enzymes, prostaglandins (PG), thromboxanes (TX) and lipoxygenase products that may be involved in PMN aggregation responses during inflammatory reactions. Granulocyte-macrophage colony stimulating factor (GM-CSF), a glycoprotein cytokine released by immunocompetent cells, has been found to prime neutrophil responses, such as increased cell aggregation after exposure to various biological stimulants. In this study, we examined the effects of the cytokine GM-CSF on human neutrophilic aggregation stimulated by N-formyl-methionyl-leucyl-phenylalanine (FMLP) and its influence on the production of various arachidonic acid metabolites. Neutrophil aggregation of purified PMNs was measured by the percent change in light transmission in a standard aggregometer, and the arachidonic acid products leukotriene B4 (LTB4) and thromboxane A2 (TXA2) were quantified by radioimmunoassay. We found that GM-CSF and other cytokines, used alone, did not cause any significant increase in aggregation of the PMN. However, prior exposure of PMN to GM-CSF markedly increased the aggregation induced by FMLP as opposed to that detected with PMN stimulated with only FMLP. This priming effect was not observed with PMN preincubated with interleukin-1 (IL-1), tumor necrosis factor (TNF) or interleukin-6 (IL-6). In addition, GM-CSF and IL-6 both failed to stimulate the production of LTB4 and TXA2, products which are known to induce PMN aggregation. These findings provide new evidence suggesting that GM-CSF facilitates the action of FMLP on the adhesion dependent cellular functions of the inflammatory response, serving as an important co-factor in neutrophil aggregation.  相似文献   
28.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
29.
30.
Fibroblast growth factors (FGFs) are related polypeptides with mitogenic activity on cells of mesodermal and neuroectodermal origin. The Fgf-3 gene shares high homology with FGF-2 and its protein product can substitute FGF-2 as a growth factor. Other observations, however, indicate that Fgf-3 has specialized functions. We have investigated the effect of the expression and secretion of Fgf-3 on the growth and transformation of the human breast epithelial cell line MCF-10A. Overexpression of Fgf-3 stimulates proliferation of these cells in serum-free medium and induces anchorage-independent colony formation in soft agar. In contrast, these effects were not observed with purified FGF-1 and FGF-2 on either the parental or the Fgf-3-MCF-10A cells. Thus, Fgf-3 is distinct from FGF-1 and FGF-2 for its ability to induce cell proliferation and transformation of MCF-10A cells. This difference could be due, at least in part, to the expression of a specific set of FGF receptors with higher affinity for FGF-3 than FGF-1 or FGF-2.  相似文献   
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