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101.
The growth fraction of tumors from patients with non-Hodgkin's lymphomas (NHL) has been shown to correlate with survival in retrospective studies. The growth fraction can be evaluated using immunohistochemical techniques employing the Ki-67 monoclonal antibody (MoAb) that marks a nuclear protein present in cycling cells. The purpose of this study was to evaluate the clinical utility of the Ki-67 MoAb for predicting survival. Using a prospective trial design in a multi-institutional cooperative trials group, the proliferative index, clinical outcome, and statistical correlations were independently assessed for previously untreated patients with advanced stages of intermediate- and high-grade histologies of NHL treated on Southwest Oncology Group study (SWOG 8516, Intergroup 0067). The proportion of Ki- 67-positive cells was determined on snap-frozen thin tissue sections. A proliferative index of 80% or greater, as determined from prior retrospective studies, identified a group of patients (18%) who had a poor outcome. Overall survival was significantly reduced in these patients with a high Ki-67-associated proliferative index compared with those with a low proliferative index (P = .001). One-year survival estimates were 82% (low proliferative index) versus 18% (high proliferative index). A multivariate regression analysis incorporating commonly used clinical prognostic features confirmed the independent effect of proliferation on survival (relative risk estimate 5.9; 95% confidence interval, 2.2, 16.1). The Ki-67 MoAb identifies a group of patients with rapidly fatal NHL for whom currently available chemotherapy is inadequate.  相似文献   
102.
Pryzwansky  KB; Wyatt  TA; Nichols  H; Lincoln  TM 《Blood》1990,76(3):612-618
The presence and physiologic role of cyclic GMP-dependent protein kinase (G-kinase) in human neutrophils was investigated by Western blot analysis and immunocytochemistry. Small quantities of G-kinase were found in the cytoskeletal-enriched fraction of neutrophil lysates as detected by Western blots using a polyclonal antibody raised against bovine aorta G-kinase. Immunofluorescence microscopy demonstrated in adherent neutrophils that G-kinase was localized diffusely within the cytoplasm, at the microtubule organizing center, and in the euchromatin of the nucleus. Because cyclic GMP is implicated as a modulator of neutrophil chemotaxis, G-kinase localization was investigated in neutrophils activated with N-formyl-methionyl-leucyl-phenylalanine (fMLP). fMLP stimulated transient focal changes in G-kinase localization that coincided with transient changes in cell shape. G- kinase translocated over a period of 5 minutes from diffuse staining of the cytosol to filaments within the uropod of polarized cells (1 minute), to bundles of filaments associated with loss of cell polarity (2.5 minutes), and finally to more intense staining of the nuclear euchromatin (5 minutes). Optical sectioning of neutrophils by confocal laser scanning microscopy confirmed that G-kinase was restricted to specific sub-cellular compartments during cell activation. This transient localization of G-kinase was disrupted by cytoskeletal inhibitors and was augmented by 8-Br-cyclic GMP. These data provide evidence for the first time that G-kinase plays a physiologic role in human neutrophils, and support the concept of compartmentalization of cyclic nucleotides during neutrophil activation.  相似文献   
103.
Donze  D; Jeancake  PH; Townes  TM 《Blood》1996,88(10):4051-4057
Hemoglobin A2 (HbA2; alpha 2 delta 2) is a powerful inhibitor of HbS (alpha 2 beta 2(3)) polymerization. However, HbA2 levels are normally low in sickle cell patients. We show that a major reason for low delta- globin gene expression is the defective CACCC box at -90 in the delta- globin promoter. When the CACCC box defect in delta is corrected, expression of an HS2 delta /Luciferase reporter is equivalent to HS2 beta /Luciferase. Erythroid Krupple-like factor (EKLF), which binds to the CACCC box of the beta-globin gene and activates high-level expression, does not bind to the normal delta-globin promoter. Our goal is to design a modified EKLF that binds to the defective delta-globin promoter and enhances delta-globin gene expression. To test the feasibility of this strategy, we inserted the beta-globin CACCC box at - 90 of the delta-globin gene promoter to produce an HS2 delta CAC-beta construct and quantitated human delta- and beta-globin mRNA in stably transformed murine erythroleukemia (MEL) cells. delta- Globin mRNA in these cells was 22.0% +/- 9.0% of total human globin mRNA (delta/delta + beta) as compared with 3.0% +/- 1.3% in the HS2 delta-beta control. In a second set of experiments a GAL4 DNA-binding site was inserted at - 90 of the delta-globin gene to produce an HS2 delta GAL4-beta construct. This construct and a GAL4(1-147)/EKLF expression vector were stably transfected into MEL cells. delta-Globin mRNA in these cells was 27.8% +/- 7.1% of total human globin mRNA as compared with 9.9% +/- 2.5% in the HS2 delta GAL4-beta plus GAL4(1-147) control. These results show that delta-globin gene expression can be significantly increased by a modified EKLF. Based on these results, we suggest that modified EKLFs, which contain zinc fingers designed to bind specifically to the defective delta-globin CACCC box, may be useful in gene therapy approaches to increase HbA2 levels and inhibit HbS polymerization.  相似文献   
104.
IntroductionThere is a need for continuous glucose monitoring in critically ill patients. The objective of this trial was to determine the point accuracy and reliability of a device designed for continuous monitoring of interstitial glucose levels in intensive care unit patients.MethodsWe evaluated point accuracy by comparing device readings with glucose measurements in arterial blood by using blood gas analyzers. Analytical and clinical accuracy was expressed in Bland-Altman plots, glucose prediction errors, and Clarke error grids. We used a linear mixed model to determine which factors affect the point accuracy. In addition, we determined the reliability, including duration of device start-up and calibration, skips in data acquisition, and premature disconnections of sensors.ResultsWe included 50 patients in whom we used 105 sensors. Five patients from whom we could not collect the predefined minimum number of four consecutive comparative blood draws were excluded from the point accuracy analysis. Therefore, we had 929 comparative samples from 100 sensors in 45 patients (11 (7 to 28) samples per patient) during 4,639 hours (46 (27 to 134) hours per patient and 46 (21 to 69) hours per sensor) for the accuracy analysis. Point accuracy did not meet the International Organization for Standardization (ISO) 14971 standard for insulin dosing accuracy but did improve with increasing numbers of calibrations and was better in patients who did not have a history of diabetes. Out of 105 sensors, 60 were removed prematurely for a variety of reasons. The device start-up time was 49 (43 to 58) minutes. The number of skips in data acquisition was low, resulting in availability of real-time data during 95% (89% to 98%) of the connection time per sensor.ConclusionsThe point accuracy of a device designed for continuous real-time monitoring of interstitial glucose levels was relatively low in critically ill patients. The device had few downtimes, but one third of the sensors were removed prematurely because of unresolved sensor- or device-related problems.

Trial registration

Netherlands Trial Registry number: NTR3827. Registered 30 January 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0757-4) contains supplementary material, which is available to authorized users.  相似文献   
105.
The stem cell inhibitor, macrophage inflammatory protein-1 alpha (MIP-1 alpha) or LD78, protects multipotent hematopoietic progenitors in murine models from the cytotoxic effects of chemotherapy. Clinical use of human MIP-1 alpha during chemotherapy could therefore lead to faster hematologic recovery and may allow dose intensification. We have also shown that human MIP-1 alpha causes the rapid mobilization of hematopoietic cells, suggesting an additional clinical use in peripheral blood stem cell transplantation. However, the clinical evaluation of human MIP-1 alpha is complicated by its tendency to associate and form high molecular weight polymers. We have produced a variant of rhMIP-1 alpha, BB-10010, carrying a single amino acid substitution of Asp26 > Ala, with a reduced tendency to form large polymers at physiologic pH and ionic strength. This greatly increases its solubility, facilitating its production and clinical formulation. We confirmed the potency of BB-10010 as a human MIP-1 alpha-like agonist in receptor binding, calcium mobilization, inhibition of colony formation, and thymidine suicide assays. The myeloprotective activity of BB-10010 was shown in a murine model of repeated chemotherapy using hydroxyurea. BB-10010 is therefore an ideal variant with which to evaluate the therapeutic potential of recombinant human MIP-1 alpha.  相似文献   
106.
107.
BACKGROUND & AIMS: Murine autoimmune gastritis, induced by day-3 thymectomy, is characterized by cellular infiltrates and circulating autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. The aim of this study was to analyze the cellular infiltrates and cytokines in autoimmune gastritis. METHODS: Stomachs and blood samples from day-3 thymectomized BALB/c mice were obtained from 2 to 12 weeks after thymectomy for analysis. RESULTS: At 4 weeks, the gastritic infiltrates were composed of macrophages and CD4+ T cells, accompanied by major histocompatibility complex class II expression on gastric epithelial cells. Mucosal B cells, scant at 4 weeks, were abundant at 8 weeks, coincident with the peaking of autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. CD8+ T cells increased marginally during the 12 weeks. Mononuclear cells from diseased stomachs transferred gastritis to nu/nu recipients. At 4 weeks, interleukins 2, 3, 5, 6, and 10; interferon gamma; tumor necrosis factor alpha; and granulocyte-macrophage colony-stimulating factor were detected in gastritic mucosa, but interleukin 4 was not. CONCLUSIONS: The early lesion of autoimmune gastritis is composed of macrophages and CD4+ T cells with major histocompatibility complex class II expression in gastric epithelial cells. Autoantibody production is a late event. Our results are consistent with a lesion mediated by CD4+ T cells producing a mix of Th1- and Th2-type cytokines. (Gastroenterology 1996 Jun;110(6):1791-802)  相似文献   
108.
Two new human myeloma cell lines have been established from a 36-year- old woman with refractory IgG kappa multiple myeloma in whom bilateral malignant pleural effusions developed. The malignant plasma cells from each effusion were set up in a liquid culture using an L-15 medium containing catalase, glutathione, selenous acid, ascorbic acid, insulin, transferrin, additional glutamine hydrocortisone, and 2- mercaptoethanol and designated as M-3 medium. Two IgG kappa cell lines, LB -831 and LB-832, were established and proved to be Epstein-Barr virus negative using the internal repeat sequence DNA probe. Characteristic plasma cell morphology was evident by light and electron microscopy. Immunotyping revealed an IgG kappa , B1+, B2-, Ia (HLA- DR)+, CALLA+ phenotype for each cell line as well as for the original pleural fluid and bone marrow myeloma cells. The supernatants also contained IgG kappa, beta 2 microglobulin, and large amounts of osteoclast-activating factor (indicating bone-resorbing activity). Cytogenetic analysis of the LB-831 cell line revealed a nearly triploid highly abnormal karyotype with numerous clonal chromosomal abnormalities involving chromosomes 1, 3, 5, 7, 13, and 15; several structurally abnormal marker chromosomes; and a putative homogeneously staining region on chromosome 7p at band p22. Analysis of the LB-832 cell line revealed several additional clonal abnormalities. These additional cytogenetic changes suggest that in vivo sequential clonal evolution occurred in this patient. Therefore, two new but related cell lines have been established, which should prove useful for further biological studies.  相似文献   
109.
Williams  DA; Lim  B; Spooncer  E; Longtine  J; Dexter  TM 《Blood》1988,71(6):1738-1743
A recombinant retrovirus (DHFR*-SVADA) in which human adenosine deaminase (ADA) cDNA is transcribed from an internal SV40 promoter was used to infect murine hematopoietic stem and progenitor cells. Human ADA enzyme was not expressed in infected primary murine pluripotent stem cell-derived spleen or progenitor colonies (CFU-GM, CFU-Mix, BFU- E). In contrast, human ADA enzyme activity was readily detected in progenitor colonies derived from immortalized multipotent factor- dependent cells. The level of human enzyme was near endogenous murine enzyme levels and was equivalent in undifferentiated stem cells and differentiated myeloid, erythroid, and mixed colonies. These results indicate that cellular properties other than the stage of differentiation are important in determining the expression of foreign sequences introduced by retroviruses. Cell lines that are immortalized but still capable of induced differentiation may contain factors that abrogate blocks to expression that are manifested in primary hematopoietic stem cells.  相似文献   
110.
A patient with Burkitt's lymphoma in complete remission received myeloablative consolidation treatment with superfractionated total body irradation (1,320 rad) and cyclophosphamide (200 mg/kg) followed by autologous transplantation of previously harvested and cryopreserved blood-derived hemopoietic stem cells. Seven successive leukaphereses were performed to yield a total of 55.2 X 10(9) mononuclear cells (MNC) comprising 15.1 X 10(6) CFU-GM or 4.34 X 10(6) CFU-GEMM. Following autologous blood stem cell transplantation (ABSCT), reconstitution of all cell lines occurred very rapidly, ie, 1,000 leucocytes per microL were reached after nine days, 500 granulocytes and 50,000 platelets per microL after ten days. B cells reached normal values around day 35 post- transplantation. CFU-GM first appeared in the circulating blood exhibiting an enormous overshoot. Some days later CFU-GM also appeared in the marrow. The kinetics and pattern of hemopoietic reconstitution after myeloablative treatment and ABSCT provide clear evidence that blood-derived hemopoietic stem cells are capable of completely restoring hemopoietic function in man. A possible reconstitutive advantage of blood over marrow-derived stem cells is discussed.  相似文献   
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