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991.
BACKGROUND: A group of 290 transfusion recipients enrolled in a prospective study of posttransfusion hepatitis was studied to determine the possibility of previously unrecognized hepatitis C virus (HCV) transmission. STUDY DESIGN AND METHODS: Before and after transfusion, blood specimens that were negative in first-generation enzyme immunoassay (EIA) were tested by current commercial EIAs, several single-antigen research EIAs, and supplemental tests. RESULTS: Current second- and third-generation EIAs identified five subjects (1.7% of total) who had chronic hepatitis C before transfusion. Twenty additional sera had some reactivity with research EIAs. However, those results were the same before and after transfusion (n = 7), had reverted to partially reactive or nonreactive (n = 8), or could not be confirmed by serologic tests or polymerase chain reaction in follow-up specimens (n = 5). CONCLUSIONS: Transient or restricted reactivity to HCV antigens measured by more sensitive research EIAs does not seem to correspond to recent HCV transmission by transfusion. Whether such reactivity could reflect remote HCV infection, with the potential for chronic or intermittent viremia, remains to be determined.  相似文献   
992.
猪源性异种骨支架材料的生物相容性   总被引:2,自引:0,他引:2  
目的:异种骨来源广泛,价格低廉,经过适当处理既能保留骨诱导作用,并作为骨支架使其具有骨传导作用。检测猪源性骨支架材料与人源性骨支架材料的生物相容性有无明显差异,为猪源性骨支架材料取代人源性骨支架材料提供实验依据。方法:实验于2006-08/2007-03在南方医科大学人体解剖学系实验室(广东省组织构建与检测重点实验室)完成。①实验材料:人源性、猪源性骨支架材料(为课题组前期制备);脂肪源间充质细胞(前期培养)。②实验方法及评估:体外细胞毒性实验:提取人源性、猪源性骨支架材料浸提液,用此浸提液培养脂肪源间充质细胞,并用无浸提液的DMEM培养基做对照,镜下观察细胞生长状况,流式细胞术检测细胞生长周期;人源性、猪源性骨支架材料皮下植入试验:于8只新西兰大白兔皮下,脊柱左侧植入异种骨支架材料,右侧植入同种异体骨支架材料。分别于4,8,12,16周将植入材料连同周围组织取出,进行组织切片观察及电镜观察。对动物处置符合动物伦理学标准。结果:①体外细胞毒性实验结果:在同一时间点,浸提液组、正常培养组细胞生长状况均良好,未见明显细胞抑制;流式细胞术检测细胞周期,3组细胞G1、G2、S期细胞百分率差异无统计学意义(P>0.05)。②皮下植入实验结果:组织切片光镜及电镜观察,4周两种植入材料周围均见结缔组织包绕,有大量巨噬细胞、浆细胞、中性粒细胞、单核细胞浸润,材料表面光滑,与结缔组织界限清楚;8周时炎症反应减轻,可见部分材料开始降解,材料表面稍显粗糙,有少量结缔组织长入材料内部;12周炎症反应基本消失、材料降解明显、异位成骨趋势明显,材料表面更加粗糙,周围有大量结缔组织长入材料;16周均无炎症反应,两种材料大部分降解,并且猪源性骨支架材料降解更为迅速,均有新骨形成,材料表面粗糙程度较12周时为甚,骨支架材料基本消失。结论:猪源性异种骨支架材料有良好的生物相容性,与人源性异种骨支架材料无明显差别。  相似文献   
993.
AIM: To study the (functional) relevance of single nucleotide polymorphisms (SNPs) in genes encoding matrix metalloproteinases (MMP)-1, -2, -3, -9, tissue inhibitors of metalloproteinases (TIMP)-1, -2 and tumor necrosis factor (TNF)-α in the etiopathogenesis of inflammatory bowel diseases (IBD), that may enhance susceptibility and/or disease severity.METHODS: Genomic DNA from 134 Crohn's disease (CD), 111 ulcerative colitis (UC) patients and 248 control subjects was isolated from resected intestinal tissue or blood. Allelic composition at SNP loci was determined by PCR-RFLP or tetra primer ARMS PCR.RESULTS: The TIMP-1 genotype ∏ in women and T in men at SNP +372 T/C was found to increase CD susceptibility (39% vs 23.8%, P = 0.018 and 67.9% vs 51.6%, P = 0.055, respectively), while women with this genotype were less prone to development of fistulae during follow-up (41.4% vs 68.3%, P = 0.025). Male IBD or CD patients carrying the TIMP-1 +372 T-allele expressed lower levels of TIMP-1 in surgically resected macroscopically inflamed tissue (0.065 < P < 0.01). The 5TST genotype at MMP-3 SNP -1613 5T/6T increased the chance of stenotic complications in CD during followup (91.2% vs 71.8%, P = 0.022) but seemed to protect against colonic involvement of this disease at first endoscopic/radiologic examination (35.3% vs 59.5%, P = 0.017).CONCLUSION: Allelic composition at the examined SNPs in genes coding for TIMP-1 and MMP-3 affect CD susceptibility and/or phenotype, i.e., fistulizing disease,stricture pathogenesis and first disease localisation.These findings reinforce the important role of these proteins in IBD.  相似文献   
994.
Foreign body granulomatosis. Clinical and immunologic findings   总被引:2,自引:0,他引:2  
We studied the clinical and immunologic features of 10 patients with foreign body granulomatosis associated with injection of pentazocine. Five had typical micronodules on chest radiographs, 9 had abnormal 67Ga lung images, and 9 had elevated serum angiotensin-converting enzyme levels. Pulmonary function tests showed significant decreases in diffusing capacity in 8 subjects, but were otherwise normal. Bronchoalveolar lavage fluid had significantly (p less than 0.02) increased total cell numbers (13.8 +/- 7.5 x 10(7) and significantly lower percentages of lymphocytes (2 +/- 1) and neutrophils (2 +/- 1) (p less than 0.02) when compared with that from control subjects. Peripheral blood lymphocytes were normal when expressed as percentages of total leukocytes or as percent T-lymphocytes. Monoclonal antibody determinations of T-lymphocyte subsets (helper and suppressor) were similar to those in control subjects (p = NS). Lymphocyte transformation responses to a variety of antigens and skin test reactivity were normal. Foreign body granulomatosis contrasts with other interstitial lung diseases in its bronchoalveolar lavage cellular profile and in the absence of altered peripheral immunologic indexes.  相似文献   
995.
To study the protein-protein interactions that allow Id, a negative regulator of cell differentiation, to inhibit the DNA-binding activities of MyoD and E47, we have synthesized peptides corresponding to the helix-loop-helix domains of MyoD, E47, and Id. We show that Id preferentially inhibits the sequence-specific DNA-binding activity of MyoD, a muscle-specific protein, as compared to E47, a more ubiquitous protein. The Id helix-loop-helix domain itself forms stable tetramers, and its inhibitory activity arises from the formation of a heterotetrameric structure with MyoD. The formation of this higher order complex provides a general mechanism by which inhibitory proteins can generate sufficient interaction free energy to overcome the large DNA-binding free energy of dimeric DNA-binding proteins.  相似文献   
996.
Sieff  CA; Ekern  SC; Nathan  DG; Anderson  JW 《Blood》1989,73(3):688-693
Previous in vitro investigations on enriched human hematopoietic progenitors have led to the conclusion that the purified recombinant multipoietins, interleukin 3 (IL-3) and granulocyte-macrophage colony- stimulating factor (GM-CSF) can alone induce the formation of colonies from a variety of multipotent and lineage committed progenitors. Since fetal calf serum was included in these cultures and itself might contain growth factors or other cofactors, we re-examined the actions of the CSFs in serum-deprived conditions. Results show that both the multipoietins are inadequate stimuli of colony formation. At maximal concentrations IL-3 alone induces only 25% of the granulocyte and macrophage colony-forming units (CFU-G and CFU-M) produced by a T-cell conditioned medium that contains a mixture of CSFs. When IL-3 was added at the initiation of the cultures and erythropoietin (ep), G-CSF, or M- CSF added on day 3, almost full recovery of erythroid, granulocytic, and monocytic colonies, respectively, was obtained. Similar results were obtained with GM-CSF except that fewer erythroid colonies were recovered at high concentrations, and almost maximal CFU-M proliferation could be induced. These results show that in serum- deprived conditions, the multipoietins must be combined with lineage specific CSFs for full progenitor expression.  相似文献   
997.
Chromosome abnormalities in Down's syndrome patients with acute leukemia   总被引:1,自引:0,他引:1  
Chromosome and cytologic studies were performed on three Down's syndrome (DS) patients with acute nonlymphocytic leukemia (ANLL). All three patients had an aneuploid clone in their leukemic cells: 50, XX, +6, +19, +21, +22, +8, XX, +21, and 47,XY, +8, - 21 +dic(21;21)(p13;p11). Every patient appeared to have acute undifferentiated leukemia when the blast cells were examined with Wright-Giemsa stain; cytochemistry studies, however, showed that the leukemic blasts were in an early stage of myeloid differentiation. The two patients with +8 had a preleukemic phase; the blast cells of the patient with an extra no. 19 and no.22 could not be differentiated morphologically from those of the two patients with an extra no. 8. Our findings and a review of data on 40 other patients suggest that most DS children with ANLL have hyperdiploidy, which is usually related to gains of C, F, and /or G chromosomes, and that the abnormalities of +8 and of +19, +22 in DS children may be associated with acute leukemia (AL) in an early stage of myeloid differentiation.  相似文献   
998.
Nieuwenhuis  HK; Akkerman  JW; Sixma  JJ 《Blood》1987,70(3):620-623
One hundred six patients with storage pool deficiency (SPD) were studied with respect to platelet count, bleeding time, total platelet ATP and ADP, platelet serotonin, and in vitro aggregation. The diagnosis of SPD was made on basis of a prolonged bleeding time, a decreased total platelet ADP, and a diminished level of serotonin. Fifty-one patients from 34 unrelated families had congenital SPD, and 55 patients had acquired SPD. Congenital SPD was a common disorder in patients with a lifelong bleeding tendency and a prolonged bleeding time. The frequency in this group of patients was 18%, about one-half the frequency of von Willebrand's disease (vWd). Twenty-three percent of all patients had normal aggregation responses to ADP, epinephrine, and collagen; 33% had aggregation tracings typical for a secretion defect; and 44% had miscellaneous aggregation abnormalities. These findings indicate that SPD is common, heterogeneous, and not necessarily associated with in vitro aggregation abnormalities.  相似文献   
999.
This article describes the course of a patient who received an allogeneic marrow graft from his HLA-identical sister for acute lymphoblastic leukemia in second remission. In the second month after grafting, marrow aspirates showed the presence of 7%-10% lymphoblasts. In addition, cytogenetic examination indicated the persistence of host cells. Thereafter, the patient had morphologically normal marrow examinations, with no evidence for recurrent leukemia. In addition, stable hematopoietic chimerism in both the lymphoid and myeloid cell lines has persisted for over 5 yr. Between 20% and 50% of phytohemagglutinin-stimulated peripheral blood mononuclear cells were host-derived on repeated studies. A marrow sample 4 yr after transplantation was established in long-term culture and produced 2% host granulocyte-macrophage colonies at its inception, but 24% host colonies by week 4. Despite this persistent chimerism, no in vitro or in vivo abnormalities of hematopoiesis have been detected.  相似文献   
1000.
It has been shown with glucose 6-phosphate dehydrogenase (G-6-PD) mosaicism that Ph1-positive chronic myelogenous leukemia (CML) is a clonal disease that involves multipotent hematopoietic stem cells. We now report G-6-PD studies of a 79-yr-old woman with Ph1-negative CML. Equal amounts of B and A-type activities were found in nonhematopoietic tissues, indicating that the patient was heterozygous for G-6-PD. In contrast, only A-type G-6-PD was found in marrow cells, blood erythrocytes, leukocytes, and platelets and in granulocyte-monocyte and eosinophil colonies grown from blood mononuclear cells. Unlike most cases of PH1-positive CML, colony growth in this patient increased during blastic transformation and the colonies contained only immature monocytic cells. The data indicate that in this patient, Ph1-negative CML is similar to the Ph1-positive form of the disease in involvement of multipotent stem cells and probable clonal origin, but the two disorders differ in the rapidity with which they enter blastic transformation and in the pattern of granulocyte-monocyte colony growth at that time.  相似文献   
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