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91.
To understand better the relationships between blood-group antigens and bacterial constituents, examples of 23 gram-negative bacteria (representing the 10 genera Citrobacter, Edwardsiella, Enterobacter, Escherichia, Klebsiella, Proteus, Pseudomonas, Salmonella, Serratia, and Shigella) were tested for the presence of Kl-like antigens by hemagglutination-inhibition (HAI) assays against both IgG and IgM anti-Kl. Saline-suspended whole organisms, cell-free culture media, and disrupted organisms were used to test for such antigens in, on, and secreted by the microorganisms examined. Disrupted organisms of an isolate of Shigella sonnei nonspecifically inhibited IgG anti-Kl as well as IgG antibodies of the specificities Kpb, Fya, S, and c. However, only Escherichia coli 0125:B15, subtype 12808, had specific K1-like activity (no activity with other IgG [(k, Kpb, Jka, Fya, S, c] and IgM [A, B, M, P1] antibodies). Disrupted organisms inhibited IgM but not IgG anti-K1 in the HAI assay. A second subtype, E. coli 0125:B15, subtype 12809, exhibited no K1-like activity. These findings support the report of K1 activity in cell-free broth cultures of E. coli 0125:B15 (subtype unspecified). Thus, although not all E. coli 0125:B15 possesses K1-like activity, the finding of such activity in at least one E. coli subtype confirms the idea that bacterial components may play a role in the production of naturally occurring antibodies directed against non-ABO red cell antigens. 相似文献
92.
Induction of proliferation of B prolymphocytic leukemia cells by phorbol ester and native or recombinant interferon-gamma 总被引:1,自引:0,他引:1
Phorbol ester phorbol myristate acetate (PMA) induces proliferation in nonmalignant human B cells and B cells from a patient with B prolymphocytic leukemia (B-PLL). Mitogen-free T cell-derived conditioned medium acts synergistically with PMA in inducing proliferation of B-PLL cells but does not enhance the PMA-stimulated outgrowth of nonmalignant B cells. Interleukin 2 (IL-2) has no effect on the outgrowth of B-PLL cells, and monoclonal antibodies against the IL-2 receptor do not influence the response to PMA and conditioned medium. Recombinant interferon-gamma (IFN-gamma), in contrast, is a potent enhancer of PMA-induced proliferation of B-PLL cells. With gel filtration techniques and with the use of anti-IFN-gamma antibodies, it is shown that IFN-gamma in the conditioned medium is responsible for the observed increase in B-PLL cell proliferation. Preincubation of B- PLL cells with IFN-gamma induces responsiveness to PMA, whereas IFN- gamma alone had no effect on these cells when pretreated with PMA. The combined data show that, in the presence of PMA, native and recombinant IFN-gamma are growth factors for B cells from a B-PLL patient and that IL-2 is not involved in this process. 相似文献
93.
Objective. To develop a sheep model of autoaugmentation omentocystoplasty and study the histologic appearance, and to compare the urodynamic results with a control group.Methods. Ten male lambs underwent a bladder autoaugmentation reinforced with an omental patch. Three were culled early, to study urothelial survival and inflammatory changes. One was sacrificed at six months to assess late histologic changes; five sheep had a urodynamic study at that stage and two died of unknown causes without further investigation. A group of seven six-month-old male sheep, of similar weights, formed the control urodynamic group.Results. The urothelial lining remained viable under the omentum, but marked inflammation and heterotopic calcification were seen within the subepithelial tissues in most of the animals. The histologic changes were reflected in the bladder dynamic data, which were no better than the control group; the average compliance value was 9.2 ± 6.4 mL/cm H2O, compared to the control group figure of 11.8 ± 5.2 mL/cm H2O.Conclusions. It would appear that autoaugmentation alone does not usually produce bladder augmentation in the sheep. 相似文献
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97.
To characterize the clinicopathological presentation of patients with myocarditis coming to autopsy in childhood, 32 cases of histologically-proven myocarditis were obtained from the files of the Adelaide Children's Hospital. In 16 of the cases (Group A), myocarditis was the only significant finding and death was ascribed to this condition. In the remaining 16 (Group B) myocarditis was found in association with other severe disease processes. Clinical histories of the 2 groups showed sudden death to be a feature in 5 out of 16 cases in Group A, 3 of whom had no prodromal symptoms. Five patients in Group B also suffered sudden death, but this was associated with a variety of causes, including bronchopneumonia, and asphyxia. These cases demonstrate the variability in clinicopathological presentation of myocarditis in infancy and childhood and suggest that myocarditis should always be considered a possible diagnosis at autopsy in the pediatric age group, even in the presence of coincident lethal disease. 相似文献
98.
Six cases of adrenal cortical tumors are presented with a discussion of the clinical features and histological findings. Five of the 6 children, aged between 6 mths and 6 yrs, presented with symptoms of hyperadrenalism, 4 with virilization and 1 with Cushingoid features. The remaining infant presented with an asymptomatic abdominal mass. In each case there was a unilateral tumor separated from the residual adrenal gland by a thin fibrous capsule. Surgical resection was the treatment employed and, in the 5 cases with functional tumors, perioperative hydrocortisone was given. None of the children received post-operative chemotherapy or radiotherapy. Bizarre cellular morphology, a high mitotic count and extensive necrosis were all seen in clinically benign disease, demonstrating not only the efficacy of local resection but also the difficulty in applying the usual histological criteria of malignancy to these pediatric adrenal tumors. At follow-up, 5 of the 6 patients are alive with no evidence of recurrent disease. The only death resulted from measles pneumonitis in the 1 child who presented with Cushing's syndrome. 相似文献
99.
Platelets are known to process human factor V during secretion and/or membrane binding. We studied the functional and structural changes produced in human factor V by purified human platelet calpain (calcium- activated thiol protease) and compared the alterations with those induced by thrombin. A maximum increase in coagulant activity of 2.5- fold was observed when factor V (1 U/mL, 33 nmol/L) was incubated with calpain (0.03 U/mL, 2.7 nmol/L) in comparison with a 8.8-fold increment for alpha-thrombin (0.7 U/mL, 8 nmol/L) at 25 degrees C. Thrombin additions to reactions initiated by calpain resulted in further activation comparable to that of thrombin alone, whereas the subsequent addition of calpain had no effect on the extent or pattern of the activation of factor V by thrombin. The cleavage pattern of factor V produced by these two enzymes are distinctly different. Although thrombin activation eventually results in four final components designated C1 (150 kd), D (105 kd), E (71 kd), and F1F2 (71 to 74 kd), calpain yields initial components of 200 kd and 160 kd within one minute. Further digestion of the 200 kd species by calpain gives rise first to a polypeptide of 160 kd that is converted to a 140 kd and a 120 kd species by two minutes with an increase in coagulant activity. Immunoblotting of these fragments with the monoclonal antibody (MoAb) B10 directed to factor V and the thrombin-generated C1 fragment yields results demonstrating a common epitope in these calpain-generated components of 200, 160, 140 and 120 kd. The degradation of the initial 160 kd polypeptide gives rise to polypeptides of 100 and 65 kd, both undetectable on immunoblotting with MoAb B10. The 130, 87, 58, and 48 kd components are of less certain origin. Thus, platelet calpain generates a complex but reproducible cleavage pattern different from thrombin that may explain the partial activation observed. Nevertheless, calpain processing may play a role in early hemostatic reactions involving platelets before the appearance of the first thrombin molecule. 相似文献
100.
Two monoclonal antibodies (anti-3-3 and anti-3-40) were produced, which identify two new leukemia-associated antigens. Both antibodies reacted with most cell lines derived from patients with T lymphoblastic leukemia (T-ALL), but were not detected on suspensions of normal hematopoietic cells (including thymocytes) by cytotoxicity, absorption, or indirect immunofluorescence assays. Analysis of fresh leukemic cells indicated that anti-3-3 only reacted with T-ALL cells, while anti-3-40 also reacted with some non-T, non-B ALL cells and a few acute myelocytic leukemia (AML) cells. The 3-40 antigen was also found histopathologically in frozen sections of several normal tissues, including the epithelial cells and a few lymphoid cells of the thymus, and some malignant tissues. The 3-3 antigen was not found in any tissue studied. A "double absorption"assay provided additional serologic evidence that the two antibodies identify different antigenic determinants. Biochemical analysis indicated that the molecules immunoprecipitated by anti-3-3 and anti-3-40 have molecular weights of 35,000-40,000 daltons. This study demonstrated that the 3-3 and 3-40 antigens are markers for human T-ALL and can be used along with the normal T-lymphocyte antigen, 3A1, to discriminate T-ALL from cutaneous T-cell lymphoma (CTCL), adult T-cell leukemia (ATL), and T-cell chronic lymphocytic leukemia (T-CLL). 相似文献