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201.
Spectrin-alpha I/61: a new structural variant of alpha-spectrin in a double-heterozygous form of hereditary pyropoikilocytosis 总被引:3,自引:0,他引:3
Recent biochemical studies have led to the identification of abnormal spectrins in the erythrocytes of patients with hereditary pyropoikilocytosis (HPP) and hereditary elliptocytosis (HE). In this report we describe the biochemical characterization of the erythrocytes from a proband with severe HPP who is doubly heterozygous for two mutant spectrins (Sp): Sp alpha I/74 and a new, previously undetected, mutant of alpha-spectrin designated Sp alpha I/61. The proband's erythrocytes are unstable when exposed to 45 degrees C, and her membrane skeletons exhibit instability to shear stress. The content of spectrin in the proband's erythrocyte membranes is decreased to 75% of control values. The amount of spectrin dimers in crude 4 degrees C spectrin extracts is increased (58%) as compared with control values (6% +/- 4%). Limited tryptic digestion reveals a marked decrease in the normal 80,000-dalton alpha I domain, an increase in the 74,000-dalton fragment that is characteristic of Sp alpha I/74, and an increase in a series of new fragments of 61,000, 55,000, 21,000, and 16,000 daltons. Both parents are asymptomatic, but they have increased amounts of spectrin dimers (17% to 25%). Limited tryptic digestion of the father's spectrin demonstrates the presence of a previously identified abnormal spectrin (Sp alpha I/74) that is characterized by a decrease in content of the 80,000-dalton peptide and an increase in concentration of the 74,000-dalton peptide. The mother's spectrin digests show a decrease in the amount of 80,000-dalton peptide and the formation of new peptides of 61,000, 55,000, 21,000, and 16,000 daltons. The data indicate that this severe form of HPP is due to the inheritance of two distinct abnormal spectrins, Sp alpha I/74 and a new spectrin mutant, Sp alpha I/61. 相似文献
202.
L Mateo Soria J Miquel Nolla Solé A Rozadilla Sacanell J Valverde García D Roig Escofet 《Annals of the rheumatic diseases》1992,51(3):402-403
Eleven cases of infectious arthritis occurring in patients with rheumatoid arthritis are reported. Staphylococcus aureus was the causative organism in eight patients. Streptococcus anginosus and Streptococcus agalactiae in one patient each, and Mycobacterium tuberculosis in two patients. The mean duration of symptoms before diagnosis was 16 days in patients with pyogenic arthritis. The diagnosis of joint infection caused by Mycobacterium tuberculosis was especially delayed (57 days). Four patients died; they were found to have a longer time to diagnosis and two of them had multiple joint infection. Although Staphylococcus aureus is the microorganism most often affecting patients with rheumatoid arthritis, infection caused by Mycobacterium tuberculosis must also be considered in such patients. 相似文献
203.
Molecular heterogeneity in MCL defined by the use of specific VH genes and the frequency of somatic mutations 总被引:1,自引:4,他引:1
Camacho FI Algara P Rodríguez A Ruíz-Ballesteros E Mollejo M Martínez N Martínez-Climent JA González M Mateo M Caleo A Sánchez-Beato M Menárguez J García-Conde J Solé F Campo E Piris MA 《Blood》2003,101(10):4042-4046
This study explores whether the presence of somatic mutations or a biased use of IgV(H) genes were associated with the clinical features in a series of 96 patients with mantle cell lymphoma (MCL). The cases were studied by seminested polymerase chain reaction using primers from the FR1 and J(H) regions. There was an unexpectedly high frequency of somatic mutations, with 29 of 103 sequences showing more than 2% of mutations. Biased usage of specific V(H) segments was also found; the most widely used genes in this series were V(H)3-21 (10 cases), V(H)3-23 (9 cases), V(H)4-34 (11 cases), and V(H)4-59 (9 cases). V(H) mutation frequency, taking into account different thresholds, did not distinguish different overall survival probabilities. Nevertheless, a more frequent use of V(H)3-21 or V(H)4-59 (8 of 18) was observed in the group of long-term survivors (18 cases > 5 years; P <.01). None of these long-term survivors presented the V(H)3-23 gene rearrangement. As in other lymphoproliferative disorders, the expression of CD38 or p53 or both was associated with a poorer survival probability. This nonrandom usage of IgV(H) segments suggests that specific antigens may play a pathogenically relevant role in the genesis or progression of subsets of MCL cases and may help in distinguishing a significant group of MCL long-term survivors. 相似文献
204.
Engraftment of bone marrow cells into normal unprepared hosts: effects of 5-fluorouracil and cell cycle status 总被引:2,自引:7,他引:2
Bone marrow from animals treated with 5-fluorouracil (5FU) competes equally with normal marrow when assessed in vivo in an irradiated mouse, but shows markedly defective engraftment when transplanted into noncytoablated hosts. Using Southern Blot analysis and a Y-chromosome specific probe, we determined the level of engraftment of male donor cells in the bone marrow, spleen, and thymus of unprepared female hosts. We have confirmed the defective engraftment of marrow harvested 6 days after 5FU (FU-6) and transplanted into unprepared hosts and shown that this defect is transient; by 35 days after 5FU (FU-35), engraftment has returned to levels seen with normal marrow. FU-6 marrow represents an actively cycling population of stem cells, and we hypothesize that the cycle status of the stem cell may relate to its capacity to engraft in the nonirradiated host. Accordingly, we have evaluated the cycle status of engrafting normal and FU-6 marrow into normal hosts using an in vivo hydroxyurea technique. We have shown that those cells engrafting from normal marrow and over 70% of the cells engrafting from FU-6 marrow were quiescent, demonstrating no killing with hydroxyurea. We have also used fluorescent in situ hybridization (FISH) analysis with a Y-chromosome probe and demonstrated that normal and post-5FU engraftment patterns in peripheral blood were similar to those seen in bone marrow, spleen, and thymus. Altogether these data indicate that cells engrafting in normal, unprepared hosts are dormant, and the defect that occurs after 5FU is concomitant with the induction of these cells to transit the cell cycle. 相似文献
205.
J. Mateo R. Martino M. Borrell M. Garí F. Casas J. Fontcuberta 《Annals of hematology》1993,67(6):309-311
Summary An acquired factor VIII inhibitor was found in an 82-year-old woman who presented with numerous spontaneously appearing ecchymoses. Coagulation studies revealed the presence of a prolonged activated partial thromboplastin time that was not corrected by 11 mixture with normal fresh plasma after a 2–h incubation. Factor VIII: C was 4%, and the titer for factor VIII inhibitor was 9 Bethesda units. Three months later, after a retroperitoneal hemorrhage, a lymphocytosis was found in her peripheral blood with morphological and surface immunophenotype characteristics of B-cell chronic lymphocytic leukemia, later confirmed by bone marrow morphological and immunocytochemical examinations. To our knowledge, this is the first report of an autoimmune factor VIII inhibitor associated with chronic lymphocytic leukemia. 相似文献
206.
207.
Cano R Prieto N Martín C Pelaz C de Mateo S 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2004,9(2):14-15
Epidemiological surveillance and control of travel associated cases of legionnaires' disease are necessary tasks for public health and collaboration between countries is necessary to do this. Within the framework of the European Surveillance Scheme for Travel Associated Legionnaires' Disease (EWGLINET), European Guidelines for Control and Prevention of Travel Associated Legionnaires' Disease have been produced . This has established the reporting and response criteria when cases or clusters appear. In this paper the analysis of the information corresponding to the 46 reported clusters related to Spain is presented. Data corresponds to the period January 2001 to July 2003. 相似文献
208.
Congenital intestinal malrotation is a developmental anomaly resulting from interruption of the physiological herniation and return to the abdominal cavity of the midgut during the 6th to 10th week of embryological development. Normal vascular and anatomic relationships used as landmarks during pancreaticoduodenectomy (PD) are altered in patients with congenital malrotation. We present 3 cases of PD in adults with congenital intestinal rotation disorders. Three adult patients with congenital rotational disorders required PD. Two of these patients had bilio-pancreatic tumors, and 1 cadaveric donor underwent total pancreatectomy during pancreas allograft procurement. All patients had arterial and venous anomalies around the celiac trunk and mesenteric vessels, respectively. The midgut and hindgut in each case were shifted toward opposite sides of the abdominal cavity. Modifications to the standard approach to PD were made, and outcomes were favorable in each case. Each patient showed anatomic abnormalities with the need for identifying vascular structures through their expected (or projected) course and location before parenchymal division or ligation of any vessel. This approach becomes crucial in cases of vascular anomalies, such as ones occurring in congenital malformations, and can be used in similar situations encountered during pancreaticoduodenectomy. 相似文献
209.
D-Dimer is an early diagnostic marker of coronary ischemia in patients with chest pain 总被引:20,自引:0,他引:20
Bayes-Genis A Mateo J Santaló M Oliver A Guindo J Badimon L Martínez-Rubio A Fontcuberta J Schwartz RS De Luna AB 《American heart journal》2000,140(3):379-384
BACKGROUND: Chest pain is a frequent symptom in the emergency department and often presents a diagnostic challenge. Because coronary thrombosis is a hallmark of acute ischemic syndromes, the substrates of the coagulation and fibrinolysis cascades may be markers of coronary ischemia. The objective of this study was to determine the diagnostic value of several hemostatic markers in patients presenting to the emergency department (ED) with chest pain syndromes. METHODS: Two hundred fifty-seven consecutive patients with acute chest pain were studied in this prospective study conducted in an urban ED. D-Dimer levels were measured at admission to the ED in all patients. We also measured thrombin-antithrombin complexes, prothrombin fragment 1+2, activated factor VII, and fibrinogen. We used regression analysis to estimate the likelihood of myocardial infarction and the diagnostic value of D-dimer. RESULTS: D-Dimer and fibrinogen levels were significantly higher in patients with acute ischemic events (myocardial infarction and unstable angina) than in nonischemic patients (P <.01 and P =.02, respectively). The other hemostatic markers were not significantly elevated in patients with ischemic events. D-Dimer level >500 microg/L had an independent diagnostic value for myocardial infarction and increased the diagnostic sensitivity of the electrocardiogram and history from 73% to 92%. CONCLUSION: D-Dimer, an expression of ongoing thrombus formation and lysis, is a marker of substantial incremental value for the early diagnosis of acute coronary syndromes presenting with chest pain. It adds independent information to the traditional assessment for myocardial infarction. D-Dimer can be incorporated into clinical decision models in the ED. 相似文献
210.
Linkage analysis demonstrates that the prothrombin G20210A mutation jointly influences plasma prothrombin levels and risk of thrombosis 总被引:15,自引:3,他引:15
Soria JM Almasy L Souto JC Tirado I Borell M Mateo J Slifer S Stone W Blangero J Fontcuberta J 《Blood》2000,95(9):2780-2785
Association studies suggest that the G20210A mutation (G to A substitution at nucleotide position 20210) in the prothrombin gene (PT) is associated with increased plasma prothrombin activity and with increased risk for venous thromboembolism. To test directly for linkage between this PT variant and plasma prothrombin activity we performed a family-based study. The G20210A genotypes and plasma prothrombin activity levels were determined in 435 individuals belonging to 22 extended Spanish families. The sample was composed of 388 homozygous (G/G) normal individuals and 43 heterozygote (G/A) and 4 homozygote (A/A) carriers for the G20210A mutation. The results of variance-component linkage analysis yielded a highly significant lod score of 3.6 (P = 2.4 x 10(-5)) between this mutation and a quantitative trait locus (QTL) that influences prothrombin activity. Importantly, a conditional linkage analysis that simultaneously accounted for association with the G20210A variant completely eliminated the linkage signal, which indicates that this mutation affects the function of the prothrombin gene. Additionally, a bivariate linkage analysis of plasma prothrombin activity and thrombosis significantly improved the linkage signal for prothrombin activity (lod score = 4.7; P = 1.5 x 10(-6)) and provided strong evidence that this QTL has a pleiotropic effect on the risk of thrombosis (lod score = 2.43; P =.0004). These results represent the first direct genetic evidence that a QTL in the PT gene influences prothrombin activity levels and susceptibility to thrombosis and strongly support the conclusion that G20210A is a functional polymorphism. (Blood. 2000;95:2780-2785) 相似文献