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991.
Busulfan-based regimens and allogeneic bone marrow transplantation in patients with myelodysplastic syndromes 总被引:1,自引:3,他引:1
Ratanatharathorn V; Karanes C; Uberti J; Lum LG; de Planque MM; Schultz KR; Cronin S; Dan ME; Mohamed A; Hussein M 《Blood》1993,81(8):2194-2199
Preparative regimens containing busulfan (BU) followed by allogeneic bone marrow transplantation (BMT) were used in 27 consecutive patients with myelodysplastic syndromes (MDS). The median age was 33 years (range, 4 to 54). Ten were female and 17 male. Sixteen patients had primary MDS, 11 other patients had antecedent hematologic diseases or developed MDS after cytotoxic and/or radiation therapy. Six patients had leukemic transformation and received antileukemic therapy before BMT. Pre-BMT cytogenetic studies showed complex chromosomal abnormalities in 13 patients, a simple abnormality in 5 patients, and normal chromosome in 8 patients. Three BU-based preparative regimens were used: 1 patient received BU 4 mg/kg orally (PO) daily for 4 days and cyclophosphamide (CY) 50 mg/kg intravenously (IV) daily for 4 days (BUCY-4); 24 patients received BU 4 mg/kg PO daily for 4 days, cytosine arabinoside (ara-C) 2 g/m2 IV every 12 hours for 4 doses, and CY 60 mg/kg IV daily for 2 days (BAC); and 2 patients with preceding Fanconi anemia received BU 2 mg/kg PO daily for 4 days followed by total lymphoid irradiation of 5 Gy. Seventeen of 27 patients are alive with no evidence of disease. Ten patients have died: 2 from hepatic veno- occlusive disease, 3 from sepsis, 1 from a cerebral bleed, 1 from a massive gastrointestinal (GI) bleed associated with acute graft-versus- host disease, 1 from hemolytic uremic syndrome with adult respiratory distress syndrome, 1 from bronchiolitis obliterans, and the only patient who did not engraft died from acute myeloid leukemia. Regimen- related toxicities (RRT) include GI tract (diarrhea, 14; stomatitis, 11), liver (9), cardiac (1), and skin (5). Patients who received a genotypically matched marrow graft had a significantly better disease- free survival (DFS) than patients who received a nongenotypic marrow graft (P = .02). The Kaplan-Meier analysis projects an overall DFS of 56% +/- 13% and 78% +/- 10% for patients who received a genotypically matched marrow graft. With the exception of a child who did not engraft, there was no relapse of MDS or leukemia. Excellent DFS, acceptable RRT, and the ease of administration are advantages of this regimen. 相似文献
992.
Fabry ME; Mears JG; Patel P; Schaefer-Rego K; Carmichael LD; Martinez G; Nagel RL 《Blood》1984,64(5):1042-1046
In an attempt to uncover potential genetic sources of the clinical diversity of sickle cell anemia, we have characterized homozygous SS patients in the following ways: percentage of dense red blood cells (% F4) as determined from Percoll-Stractan continuous density gradients, alpha gene deletion, average percentage of hemoglobin F (% HbF), hemoglobin in g/dL, age, and sex. We find that alpha 4 individuals have a higher % F4 (mean 24% +/- 15%) than alpha 3 individuals (mean 12% +/- 8%) (P less than .005). Multivariate analysis demonstrated a significant correlation among % F4 levels and alpha-gene number and % HbF, and an interaction between the last two variables. The other variables considered did not significantly alter this model. As reported before, with fewer samples, we find that in the first ten years of life of SS individuals, the frequency of alpha gene deletion is 17%, which is comparable to that in the general black population, while in the group over 20 years of age, the frequency rises to 49%, implying that alpha thalassemia is associated with longer survival. These results indicate that it is necessary to consider sickle cell anemia not only as a single gene defect, but also as a disease whose clinical expression is the result of a group of genes capable of interacting at the phenotypic level. 相似文献
993.
Eyster ME; Whitehurst DA; Catalano PM; McMillan CW; Goodnight SH; Kasper CK; Gill JC; Aledort LM; Hilgartner MW; Levine PH 《Blood》1985,66(6):1317-1320
Immunologic abnormalities resembling those seen in patients with the acquired immunodeficiency syndrome (AIDS) are frequently observed in multitransfused but otherwise healthy individuals with hemophilia. To determine whether there was clinical or laboratory evidence to suggest an abnormality of immunoregulation in persons with hemophilia before the recognition of AIDS, we examined data collected by the Hemophilia Study Group from 1975 to 1979 on 1,551 patients with factor VIII deficiency. The prevalence of lymphocytopenia and thrombocytopenia in patients over 5 years of age on entry was found to be 9.3% (94/1,013) and 5.0% (26/518), respectively. These rates were significantly different from a normal population (P less than .00001 and less than .0003). No cases meeting the definition of AIDS were noted during the study. However, on follow-up in 1984 of a cohort of 79 patients with thrombocytopenia or lymphocytopenia on two or more occasions during the study, eight patients (10%) with AIDS-related abnormalities, including idiopathic thrombocytopenic purpura, non-Hodgkin's lymphoma, generalized lymphadenopathy, and oral moniliasis without obvious cause were identified. Of the 79 patients, liver disease accounted for five of the ten deaths (12.6% mortality) observed during a minimum follow-up of five years after detection of cytopenia. Only one death was attributed to bleeding in the absence of liver disease. We conclude that (a) the frequency of lymphocytopenia and thrombocytopenia was increased in multitransfused factor VIII-deficient hemophiliacs before the advent of AIDS, and (b) persistent lymphocytopenia and thrombocytopenia appear to be strongly associated with liver disease, which was the leading cause of death in a cohort of hemophiliacs followed five or more years. 相似文献
994.
S. Y. De Boer MD Dr. A. A. M. Masclee MD PhD W. F. Lam J. Schipper MD PhD J. B. M. J. Jansen MD PhD C. B. H. W. Lamers MD PhD 《Digestive diseases and sciences》1993,38(12):2228-2235
The aim of the present study was to investigate the effect of acute hyperglycemia on (1) the intestinal phase of gallbladder contraction induced by the intraduodenal administration of emulsified fat, and (2) the small intestinal transit time measured by the lactulose breath hydrogen test. Six healthy volunteers were studied in random order during normoglycemia and hyperglycemia (blood glucose levels 15 mmol/liter). Gallbladder volumes were measured with ultrasonography. Administration of 1 and 2 g/hr of fat resulted in significant reductions in gallbladder volumes from 24±2 cm3 to 11±1 cm3 (P<0.05) and 8±1 cm3 (P<0.05), respectively during normoglycemia, and from 24±2 cm3 to 21±2 cm3 (P<0.05) and 16±2 cm3, respectively (P<0.05) during hyperglycemia. Compared to normoglycemia, the gallbladder contraction was significantly (P<0.05) reduced during hyperglycemia. No significant differences in CCK secretion were observed between experiments. Small intestinal transit time during hyperglycemia (101±12 min) was significantly (P<0.05) prolonged compared to normoglycemia (57±12 min). During hyperglycemia, basal PP levels and PP secretion in response to intraduodenal fat were significantly (P<0.05) reduced compared to normoglycemia. It is concluded that (1) low doses of intraduodenal emulsified fat result in significant gallbladder contraction and CCK secretion, (2) acute hyperglycemia inhibits intraduodenal fat induced gallbladder contraction, (3) acute hyperglycemia does not affect the intraduodenal fat induced CCK secretion, (4) small intestinal transit is significantly prolonged during acute hyperglycemia, and (5) acute hyperglycemia inhibits basal and stimulated plasma PP secretion, suggesting impaired vagal-cholinergic tone during hyperglycemia. 相似文献
995.
Effect of acute hyperglycaemia on gall bladder contraction induced by cholecystokinin in humans.
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S Y de Boer A A Masclee M C Jebbink J Schipper H H Lemkes J B Jansen C B Lamers 《Gut》1993,34(8):1128-1132
This study examined the effect of acute hyperglycaemia, induced by intravenous glucose, on gall bladder motility. Six healthy volunteers were studied in random order on three occasions during normoglycaemia and hyperglycaemia with blood glucose concentrations stabilised at 8 and 15 mmol/l. Gall bladder volumes, measured with ultrasonography, were studied before and during infusion of stepwise increasing doses of cholecystokinin (CCK-33; 0.25, 0.5, and 1.0 IDU.kg-1.h-1). Each dose was given for 30 minutes. Pancreatic polypeptide (PP) secretion was determined as an indirect measure of cholinergic tone. Infusion of CCK-33 resulted in significant dose dependent reductions in gall bladder volume in all three experiments. Compared with normoglycaemia the gall bladder contraction was significantly (p < 0.05) reduced during infusion of 0.25 and 0.5 IDU kg-1.h-1 CCK-33 in the 8 mmol/l hyperglycaemic experiment, and during infusion of 0.25, 0.5, and 1.0 IDU kg-1.h-1 CCK-33 in the 15 mmol hyperglycaemic experiment. During hyperglycaemia basal plasma PP concentrations and PP secretion in response to CCK-33 were significantly (p < 0.05) reduced. It is concluded that blood glucose concentrations affect gall bladder motility, that an acute hyperglycaemia at 8 and 15 mmol/l reduces the gall bladder responsiveness to CCK-33 in a dose dependent manner, and that hyperglycaemia reduces basal and CCK-33 stimulated plasma PP concentrations, suggesting impaired cholinergic activity during hyperglycaemia. 相似文献
996.
REN-XIAO SUN J. COSTE C. SEGARA T. ROUSSET M. FABBRO T. RME E. LEGOUFFE B. KLEIN J.-F. ROSSI 《International journal of laboratory hematology》1998,20(2):87-94
Non-Hodgkin‘s lymphomas (NHL) are B-cell malignancies which generally present molecular abnormalities, such as bcl-2 translocation t(14; 18) predominantly in the follicular subgroup. Other molecular events have been described in NHL, including p53 gene mutation and overexpression of one chemoresistance mechanism, the multidrug resistance system, P-glycoprotein (MDR1/P-gp). In this study, we analysed samples from 44 NHL patients with the presence of the bcl-2 major breakpoint region (MBR) rearrangement in 29 and without in 15. Immunochemical analysis revealed that 39 samples were positive for bcl-2 protein expression in tumoral cells (88.6%). Seventeen (38.6%) patients expressed P-gp and 9 (20.5%) expressed p53 proteins. Eleven patients expressed both bcl-2 and P-gp proteins, four expressed bcl-2 and p53 proteins whereas four expressed bcl-2, p53 and P-gp proteins. Our results confirm the importance of p53 expression as a key prognostic factor, and no objective response (OR) was found in patients with p53 positivity. MBR rearrangement was not associated with poor response to chemotherapy (62.1% OR in MBR positive patients v. 60% OR in MBR negative patients). The clinical impact of P-gp cannot be identified because no relationship was observed between P-gp expression and prognosis (58.8% OR in P-gp positive patients v. 63% OR in P-gp negative patients). 相似文献
997.
Total lymphoid irradiation and cyclophosphamide as preparation for bone marrow transplantation in severe aplastic anemia 总被引:1,自引:0,他引:1
Ramsay NK; Kim T; Nesbit ME; Krivit W; Coccia PF; Levitt SH; Woods WG; Kersey JH 《Blood》1980,55(2):344-346
A new combination of total lymphoid irradiation and cyclophosphamide was used prior to bone marrow transplantation in an attempt to achieve decreased rejection rates and graft-versus-host disease. Nine previously transfused patients with severe aplastic anemia received marrow from an HLA-identical, MLC-compatible sibling following this preparative regimen. There were no episodes of graft rejection, and only one patient developed graft-versus-host disease. Of the 9 patients, 7 (78%) are surviving with a median follow-up of 400 days. The excellent results of this pretransplant combination of total lymphoid irradiation and cyclophosphamide warrants application of this regimen to a larger series of patients. 相似文献
998.
Effect of leukocyte antibodies on the fate in vivo of indium-111- labeled granulocytes 总被引:1,自引:0,他引:1
The effect of different leukocyte antibodies on the fate in vivo of granulocytes is not known. Thus, the optimum in vitro serologic tests to determine a safe and effective granulocyte transfusion or to diagnose immune destruction of granulocytes in other clinical situations have not been identified. We have studied the effect of granulocyte agglutinating (GA), granulocytotoxic (GC), and lymphocytotoxic (LC) antibodies on the intravascular recovery and half- life (t 1/2) and the extravascular localization of Indium-111- granulocytes in 50 patients. GA antibodies caused reduced granulocyte recovery and t 1/2 in three of three non-neutropenic patients (one with anti-NB1), increased sequestration of cells in the liver, and failure of granulocytes to localize at sites of infection in two of two patients (one with anti-NA1). In contrast, GC antibodies in five patients and LC antibodies in one patient did not cause reduced intravascular recovery or t 1/2 of granulocytes. In nine patients with GC and six patients with LC antibodies, incompatible granulocytes localized at known sites of infection. It appears that GA, but not GC nor LC, antibodies alter the fate in vivo of granulocytes. 相似文献
999.
Phosphorylated HSP27 associates with the activation-dependent cytoskeleton in human platelets 总被引:1,自引:0,他引:1
The three prominently phosphorylated 29-kD proteins in thrombin- activated human platelets are forms of the mammalian 27-kD heat-shock protein (HSP27). Though the function of HSP27 is not yet known, its phosphorylation is highly correlated with platelet secretion, and recent evidence in nonhematopoietic cells suggests that HSP27 regulates cortical actin filament assembly. Therefore, the subcellular location and phosphorylation state of HSP27 in resting and thrombin-activated platelets was studied. Platelets were fractionated by established Triton X-100 lysis methods followed by differential centrifugation to obtain the 14,000g fraction (low-speed cytoskeleton), 100,000g fraction (membrane skeleton), and the 100,000g supernatant fraction containing soluble cytosolic proteins. In resting platelets, HSP27 was present principally in the 100,000g supernatant fraction. Platelet activation with thrombin led to translocation of the majority of HSP27 to the low- speed cytoskeleton. This association was reversible by DNase, supporting the idea that HSP27 is a specific component of the actin cytoskeleton. Immunofluorescence studies similarly showed HSP27 is cytoplasmic in resting platelets but colocalizes with actin in fully spread, glass-activated platelets. Immunoprecipitation studies showed a small amount of constitutively phosphorylated HSP27 in resting platelets, but phosphorylation of the majority of HSP27 after thrombin activation. After activation, virtually all phosphorylated HSP27 was found in the low-speed cytoskeletal fraction, and each of the three phosphorylated forms of HSP27 were present by two-dimensional autoradiography. Furthermore, in time-course studies, the phosphorylation of HSP27 occurred just before localization of HSP27 to the low-speed pellet. These results show that, after platelet activation, HSP27 is first phosphorylated and then translocated from the cytoplasm to the assembling cytoskeleton, and suggest that HSP27 phosphorylation may be important to the binding of HSP27 to cytoskeletal components and the cytoskeletal rearrangements characteristic of platelet activation. 相似文献
1000.
Abnormal autologous mixed lymphocyte reaction in autoimmune thrombocytopenic purpura 总被引:2,自引:0,他引:2
The autologous mixed lymphocyte reaction (auto-MLR) measures the ability of non-T cells to stimulate autologous T cells to proliferate in tissue culture. The auto-MLR was studied in 11 patients with autoimmune thrombocytopenic purpura (ATP). Seven patients had decreased auto-MLR, which averaged 4440 +/- 3364 cpm (SEM) compared to 15,360 +/- 6905 cpm for simultaneously studied controls. The average of the ratios of cpm incorporated by patients/cpm incorporated by control subjects was 0.20 +/- 0.06 (p less than 0.01). Serum from all 7 patients with low auto-MLR decreased the auto-MLR of normal subjects by an average of 56% +/- 8.5 (p less than 0.001). Preliminary results indicate that the inhibitory effect was mediated by a component of the IgG immunoglobulin fraction of serum. Sera from normal persons and from ATP patients with normal or high auto-MLR did not affect the auto-MLR of normal subjects. It was further shown that non-T cells from 3 of 5 patients with decreased auto-MLR failed to stimulate allogeneic T cells normally. It is concluded that many patients with ATP have decreased auto-MLR apparently due to the presence of a serum blocking factor and, perhaps, a defective stimulatory capacity of non-T-cells. 相似文献