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91.
Abstract The objective of this study was to evaluate the utility of a polymerase chain reaction (PCR) assay in detecting Mycobacterium tuberculosis in bronchoalveolar lavage (BAL) specimens of patients suspected of having active pulmonary tuberculosis (TB) but who were sputum smear-negative. Patients undergoing investigation for suspected pulmonary TB at the University Hospital, Kuala Lumpur, and who were sputum smear-negative underwent fibreoptic bronchoscopy and BAL. One portion of each lavage specimen was submitted for smear examination for acid-fast bacilli and mycobacterial culture and the other portion assayed by PCR for the presence of a 562-base pair DNA segment belonging to the insertion sequence IS986, unique to the M. tuberculosis complex. As controls, lavage specimens from patients with other lung lesions were also similarly tested. The PCR assay gave a positivity rate of 80.9% (55 of 68) compared with 8.8% of smear examination and 7.4% of culture for detecting M. tuberculosis in BAL specimens. The assay was positive in two of 45 BAL specimens from 35 control subjects. The PCR assay was more sensitive than smear and culture in detecting M. tuberculosis in BAL specimens of patients with sputum smear-negative pulmonary TB. 相似文献
92.
Norman I. Levenson Robert J. Adolph Donald W. Romhilt Marjorie Gabel Vincent J. Sodd Leon S. August 《The American journal of cardiology》1975,35(2):251-257
The effect of regional myocardial ischemia and hypoxia on myocardial scintigraphy was studied in patients and dogs after intravenous administration of cesium-129. Seven men with angiographically proved ischemic heart disease underwent exercise testing and 129Cs was given immediately when ischemia was manifested in the electrocardiogram. Defects were not evident in the scintigrams of any patient. Failure to visualize a defect might be related to delayed uptake of 129Cs by the myocardium (maximal uptake in 45 minutes). The ischemic state was dissipated before the disparity in uptake between normal and ischemic myocardium could be visualized. Cesium-129 is useful for identifying acute myocardial infarcts but should not be used to visualize transient exercise-induced regional ischemia.Six dogs were given 129Cs after induction of regional myocardial hypoxia by perfusion of the anterior descending coronary artery with venous blood. In each, scintigraphy revealed a defect that resolved after reperfusion with arterial blood. Two other dogs were given 129Cs before perfusion with hypoxemic blood; neither dog manifested a defect. Since perfusion was maintained by a pump these results suggest that the major cause of the scintigraphically observed defect was inadequate cellular uptake of 129Cs rather than excessive cellular loss. Since regional myocardial hypoxia produced a reversible defect, scintigraphic studies might overestimate the size of an acute myocardial infarct in man by including the ischemic zone surrounding the infarct. 相似文献
93.
Pneumatosis cystoides intestinalis is a rarely observed disorder on plain abdominal X-ray or colonoscopy examination. Although causing few complaints in adults, it can nevertheless lead to gastrointestinal bleeding. In the reported case, gastrointestinal bleeding was observed with coinciding pneumatosis and phenprocoumon therapy. After stopping anticoagulant therapy, pneumatosis vanished completely, thus suggesting that phenprocoumon is probably a further cause of the cystic disease. In the known list of drugs able to provoke pneumatosis, this case adds a new mechanism of affliction different to either immunosuppression or gas production. 相似文献
94.
Ohne ZusammenfassungStudie im Rahmen des Assoziationsvertrages Hämatologie EURATOM-GSF Nr. 031-64-1 BIAD. 相似文献
95.
UVB irradiation (700 J/m2) of bone marrow cells (UVB-BMC) before transplantation into lethally gamma-irradiated (10.5 Gy) allogeneic rats prevents graft-versus-host disease (GVHD) and induces a stable complete lymphohematopoietic chimerism. To better understand the underlying mechanism of the development of stable chimerism and induction of tolerance to donor organs in this model, we examined if the addition of T cells or dendritic cells (DC), as antigen presenting cells (APC), would restore the immunogenicity of UVB-BMC in in vitro mixed lymphocyte reaction (MLR) and induce in vivo bone marrow (BM) graft rejection. Whereas gamma-irradiated, unfractionated BMC induce allogeneic T cells to proliferate, UVB irradiation of BMC abolishes the stimulatory capacity of such cells in a primary MLR. Addition of purified T cells, CD4+ T cells, CD8+ T cells or B cells, respectively, failed to restore the capacity of UVB-BMC to stimulate allogeneic T- cell proliferation. In contrast, the addition of only a small number of splenic accessory cells or purified DC, which by themselves were relatively ineffective in stimulating T-cell proliferation, restored the accessory function and the allostimulatory capacity of UVB-BMC. To define the molecular defect induced by UVB irradiation, cytokines were added as costimulatory factors to primary MLRs and the results showed that the addition of interleukin (IL)-2 or IL-6 but not IL-1 or interferon gamma (IFN-gamma) restored the stimulatory capacity of UVB BMC. This finding suggests that UVB may alter the production, and/or utilization of IL-2 and IL-6 either at the membrane or cytoplasmic level. Parallel in vivo studies showed that addition of DC to UVB BM inoculum resulted in failure of BM engraftment, whereas addition of T cells led to development of fatal GVHD, thus suggesting that UVB modulation of accessory cells reduces graft immunogenicity and prevents BMT rejection, while modulation of T cells prevents GVHD. Our data provide evidence that UVB modulation of APC and mature T cells contained within BMC is potentially useful in preventing GVHD without endangering successful engraftment and may serve as a model for induction of adult chimerism and tolerance without the development of GVHD. 相似文献
96.
Background
Pneumocystis jiroveci pneumonia (PCP) is an important opportunistic infection among immunosuppressed patients, especially in those infected with human immunodeficiency virus (HIV). The clinical presentation of PCP in immunosuppressed patients have been well-reported in the literature. However, the clinical importance of PCP manifesting in the setting of an immunorestitution disease (IRD), defined as an acute symptomatic or paradoxical deterioration of a (presumably) preexisting infection, which is temporally related to the recovery of the immune system and is due to immunopathological damage associated with the reversal of immunosuppressive processes, has received relatively little attention until recently. 相似文献97.
Saul Miller Kevin Gabel Christine H Lee 《Journal canadien des maladies infectieuses》2008,19(3):253-255
Each year, increasing numbers of people from developed countries travel to developing countries. It is not rare for these travellers to experience illness during or following their trips. It has been estimated that fever is present in 25% of those who seek medical attention following travel. In the majority of cases, the focus of the investigations centre around an infectious etiology, which can lead to a delay in establishing the noninfectious cause of fever. Two cases of fever, which were due to a noninfectious disease, are reported in returning travellers. 相似文献
98.
Immunologic heterogeneity of diffuse large cell lymphoma 总被引:2,自引:0,他引:2
Freedman AS; Boyd AW; Anderson KC; Fisher DC; Pinkus GS; Schlossman SF; Nadler LM 《Blood》1985,65(3):630-637
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs. 相似文献
99.
Gene Conway Noble O. Fowler Robert A. Heazlitt Marjorie Gabel Steele Mattingly John C. Holmes 《Journal of molecular and cellular cardiology》1979,11(12):1215-1226
This work was done to evaluate the response of cardiac myosin ATPase in the compensated heart subjected to the increased volume work of a high cardiac-output state.Dogs with bilateral femoral arteriovenous fistulas were studied either 14 days (acute arteriovenous fistulas) or a mean of 230 days (chronic arteriovenous fistulas) after construction of the fistulas. Dogs with anemia secondary to repeated bleeding (anemic) were studied 14 days after a high output state was first documented.Calcium-activated myosin adenosine-triphosphatase (ATPase) activity was significantly elevated for the anemic and acute arteriovenous fistula dogs, but the elevations were not significant for myosin from the chronic arteriovenous fistula dogs. In the presence of K+ and EDTA, the cardiac myosin ATPase activity was generally elevated for the anemic, less so for the acute arteriovenous fistula and was normal for the chronic arteriovenous fistula.The Ca2+ uptake (in the presence of oxalate) by the cardiac sarcoplasmic reticulum was significantly less than normal for all three groups. 相似文献
100.