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31.
Predicting cholangiocarcinoma in patients with primary sclerosing cholangitis before transplantation.
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Patients with primary sclerosing cholangitis are at an increased risk of developing cholangiocarcinoma, which is difficult to diagnose because the biliary tree is already distorted. Eleven patients with primary sclerosing cholangitis who underwent orthotopic liver transplantation at this hospital were evaluated. Four patients had coincidental histologically proved cholangiocarcinoma. Patients with cholangiocarcinoma in contrast to patients without tumour presented with rapid onset of persistent jaundice, pruritus, and weight loss associated with an appreciable rise in bilirubin (8x v 2x) and alkaline phosphatase (3.5x v 1.2x) over one year. Cholangiography and computed tomography showed appreciably dilated intrahepatic bile ducts (3/4 v 0/7). The diagnosis of cholangiocarcinoma could only be established before operation in one patient by fine needle aspiration cytology. Tumour was recognised at operation in one other. Histological examination of hepatectomy specimens showed that patients with cholangiocarcinoma had less advanced histological features of primary sclerosing cholangitis. Multiple areas of carcinoembryonic antigen positive epithelial atypia and carcinoma in situ were found in all patients with cholangiocarcinoma. Cholangiocarcinoma recurred in two patients at 14 and 39 months after transplantation. Superimposed cholangiocarcinoma can be predicted in most patients with cholangitis before transplantation, although a definitive diagnosis is difficult to make. Their prognosis after successful transplantation is guarded. 相似文献
32.
Dissecting aneurysms of the vertebral arteries following cervical manipulation: a case report. 总被引:1,自引:1,他引:0
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J W Dunne G N Conacher M Khangure C G Harper 《Journal of neurology, neurosurgery, and psychiatry》1987,50(3):349-353
Neck manipulation may uncommonly be associated with serious and even fatal vascular complications. Although well recognised, the nature of the vascular injury has only rarely been directly established by pathological examination. The case is reported of a 43-year-old man who died following neck manipulation, and in whom multiple dissecting aneurysms within both vertebral arteries were demonstrated radiologically and found at necropsy. Bilateral dissecting aneurysms were found both at the level of atlanto-axial articulation and close to the origins of the vertebral arteries. No predisposition was found, other than early atheroma consistent with the patient's age. 相似文献
33.
34.
Summary The pharmacokinetics of single intravenous and oral doses of L-carnitine 2 g and 6 g has been investigated in 6 healthy subjects on a low carnitine diet.Carnitine was more rapidly eliminated from plasma after the higher dose. Comparing the 2-g and 6-g doses, the t1/2 of the elimination phase () was 6.5 h vs 3.9 h, the elimination constant was 0.40 vs 0.50 h–1 and the plasma carnitine clearance was 5.4 vs 6.11 × h–1 (p<0.025), thus showing dose-related elimination.Saturable kinetics was not found in the range of doses given. The apparent volumes of distribution after the two doses were not significantly different and they were of the same order as the total body water. Urinary recoveries after the 2-g and 6-g doses were 70% and 82% during the first 24 h, respectively.Following the two oral dosing, there was no significant difference in AUCs of plasma carnitine. Urinary recoveries were 8% and 4% for the 2-g and 6-g doses during the first 24 h. The oral bioavailability of the 2-g dose was 16% and of the 6 h dose 5%. The results suggest that the mucosal absorption of carnitine is already saturated at the 2-g dose. 相似文献
35.
Coagulation changes following hepatic revascularization during liver transplantation 总被引:1,自引:0,他引:1
P L Harper R J Luddington I Jennings D Reardon M J Seaman R W Carrell J R Klink M Smith K Rolles R Calne 《Transplantation》1989,48(4):603-607
The coagulation changes during liver transplantation have been studied in 14 selected patients. Blood usage in all cases was limited to 8.5 liters, and the preoperative coagulation results were only minimally deranged. Bleeding during the operative procedure was easily managed in all cases. Nonetheless, even in this selected group of "low risk" patients, we have demonstrated that during the anhepatic phase and particularly following hepatic revascularization there is activation of both coagulation and fibrinolysis. These findings imply that if bleeding occurs following revascularization, in addition to the use of replacement blood products, treatment should be directed at reducing the consumptive coagulopathy and inhibiting fibrinolysis. We suggest as a first step antithrombin supplementation to maintain activity above 70%, and an antifibrinolytic agent, such as aprotonin, should be considered as adjuncts to therapy at revascularization. 相似文献
36.
The use of linked DNA polymorphisms for genotype prediction in families with Duchenne muscular dystrophy. 总被引:6,自引:2,他引:6
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P S Harper T O''Brien J M Murray K E Davies P Pearson R Williamson 《Journal of medical genetics》1983,20(4):252-254
Two DNA restriction fragment length polymorphisms show genetic linkage to the Duchenne muscular dystrophy locus on the short arm of the X chromosome. Examples are given of families in which these polymorphisms can be used in the prediction of genotype for this disorder. 相似文献
37.
Human ovarian granulosa cells and follicular fluid indices: the relationship to oocyte maturity and fertilization in vitro 总被引:1,自引:0,他引:1
The study investigates the correlation between oocyte maturity and
fertilization and a variety of hormonal parameters in follicular fluid and
ovarian granulosa cells. A methodology for purification of granulosa cells
from contaminating blood cells is also established. A total of 63
follicular aspirates were collected at oocyte retrieval from 30 women
superovulated using the long luteinizing hormone- releasing hormone (LHRH
analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone,
testosterone and human chorionic gonadotrophin (HCG) were quantified in
follicular fluid and granulosa cells were immunostained for human chorionic
gonadotrophin. Immunopurification of granulosa cells from contaminating
blood cells was performed. HCG in follicular fluid was significantly high
in follicles yielding immature (grade 3) oocytes (P=0.002); there was no
correlation with fertilization. Aspirates from follicles containing mature
(grade 1) oocytes and oocytes that subsequently fertilized had
significantly more granulosa cells immunobound to HCG (P < 0.001,
P=0.02). Moreover, the immunomagnetic purification technique provided
>98% pure population of granulosa cells. The data demonstrate that HCG
in follicular fluid and on granulosa cells may help to predict oocyte
maturity and fertilization. Furthermore, immunomagnetic beads provide a
reliable procedure for the purification of ovarian granulosa cells.
相似文献
38.
Laboratory infection of primates with Ascaris suum to provide a model of allergic bronchoconstriction 总被引:2,自引:1,他引:2
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D I Pritchard R P Eady S T Harper D M Jackson T S Orr I M Richards S Trigg E Wells 《Clinical and experimental immunology》1983,54(2):469-476
Wild-caught non-human primates are naturally sensitive to Ascaris antigen and provide a useful model for studying atopic asthma. The present study was carried out to determine the effect of experimentally infecting home-bred macaques with the nematode Ascaris suum and hence provide an alternative for the naturally occurring model. Following oral infection with the parasite the animals developed a blood eosinophilia and specific antibodies to purified Ascaris antigen. These antibodies appeared to be of the IgE class as they could be detected by a radiometric assay using a radiolabelled antibody to human IgE. However, on further investigation, using the passive cutaneous anaphylaxis test, two classes of antibody were found, a heat labile (56 degrees C) and a heat stable antibody. Lung lavage cells taken from monkeys infected with Ascaris suum were shown to include cells morphologically characteristic of mast cells and released histamine when challenged in vitro with Ascaris antigen. Hence this model of immediate hypersensitivity provides a simple alternative to the less accessible natural model. 相似文献
39.
J S Krauss D A Hahn D Harper S Shell C R Baisden 《Annals of clinical and laboratory science》1987,17(5):331-338
The glycated hemoglobin (GHb) is lowered by hemolytic anemia. The cation-exchange HbA1 has been shown to be lowered by hereditary spherocytosis (HS). The HbA1, however, can be increased by elevations of fetal hemoglobin (HbF). The affinity GHb, a parameter related to, but not identical with, the HbA1, and unaffected by HbF, has been shown to be low in hemoglobinopathies but not, to our knowledge, in HS and other non-hemoglobinopathic hemolytic anemias. Therefore, the affinity GHb and HbF was determined in four members of an HS family and in nine other cases of non-hemoglobinopathic hemolytic anemia, including three autoimmune hemolytic anemias, four red cell fragmentation syndromes (two "Waring blender" syndromes, one thrombotic thrombocytopenic purpura in association with tumor, and one case of disseminated intravascular coagulation), and two red cell membrane defects: paroxysmal nocturnal hemoglobinuria and another case of hereditary spherocytosis. The GHb for these nine cases was 3.6 +/- 1.7 percent (normal 6.0 +/- 2.0 percent; p less than 0.001). The reticulocyte count, available in four cases, was 0.23 +/- 0.14 and correlated negatively with the GHb. The average GHb in the HS family was 3.9 +/- 0.8 percent, which was significantly less than the normal of 6.0 +/- 2.0 percent (p less than 0.001); the HbF was less than 1.0 percent. It is concluded that the GHb is diminished in hemolytic anemias not associated with hemoglobinopathies and that this lowering reflects the shortened red cell life span in these processes. To our knowledge, this is the first report of low GHb in hemolytic anemia not associated with hemoglobinopathy, by the affinity chromatographic technique, as opposed to the cation-exchange chromatographic technique. 相似文献
40.
Marfan syndrome: exclusion of genetic linkage to the COL1A2 gene 总被引:11,自引:0,他引:11
Marfan Syndrome is a genetic disorder of the connective tissue. Individuals from one large family with this disorder were genotyped for COL1A2 gene associated RFLPs. Our results demonstrated that the COL1A2 gene, encoding the proa2(I) collagen chain, segregated independently of the phenotype and it is therefore excluded as the mutant locus in this family. 相似文献