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81.
Patients with the syndrome of chronic daily headache often report migrainous symptoms and consequently are diagnosed as having a primary headache syndrome. We report two cases of idiopathic intracranial hypertension causing chronic daily headache with migrainous features in the absence of associated papilledema. 相似文献
82.
83.
PM Braillon AL Guibal P Pracros-Deffrenne A Serban JP Pracros P Chatelain 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(9):924-929
Ninety five normal Caucasian subjects (51F, 44 M) aged from 2 to 25 y were measured at the hand and wrist level with a small DXA system (pDEXA™) in order to obtain the normal values of the bone mineral content (BMC), density (BMD) and projected area (A) of carpal (c) and metacarpal (m) bones. BMDc ranged from 0.065 ± 0.007 g/cm to 0.365 ± 0.035 g/cm in females and 0.425 ± 0.040 g/cm in males. It presented a sharp change of increase rate at 15.5 and 17 y of age in girls and boys, respectively. Ac presented the same kind of evolution as BMDc, but had a larger value dispersion. The second metacarpal bone had the highest BMCm value in 85% of females and 90% of males. The sum of BMCmi or Ami values (i = 1–5) and the projected mean density of the 5 metacarpal bones was well correlated with BMCc, Ac and BMDc, respectively ( r > 0.90). A volumetric mineral density, dmi, calculated for each of these bones, approximated to a cylinder, was correlated with age ( r > 0.85). 相似文献
84.
85.
Gamma-carboxylated isoforms of recombinant human protein S with different biologic properties 总被引:3,自引:0,他引:3
Grinnell BW; Walls JD; Marks C; Glasebrook AL; Berg DT; Yan SB; Bang NU 《Blood》1990,76(12):2546-2554
Human protein S (HPS), a regulator of hemostasis, is a vitamin K- dependent plasma protein with potential clinical utility. We have obtained high-level expression of the cDNA for HPS in two mammalian cell lines. Both cell lines secreted single chain recombinant HPS (rHPS) in serum-free medium as determined by Western blot analysis. The ability of the rHPS from both cell lines to act as a cofactor for human protein C (HPC) was determined; the rHPS secreted from the human 293 cell line had an activity six times that of the rHPS from the AV12-664 Syrian hamster cell line. Furthermore, the relative specific cofactor activity of rHPS from the 293 cell line was actually 2.5-fold higher than that of single-chain human plasma-derived HPS. Essentially all of the rHPS secreted from the 293 cell line exhibited a calcium-dependent elution profile on anion exchange chromatography, whereas only 25% to 35% of the hamster cell-derived rHPS exhibited this profile. However, the calcium-eluted rHPS from the AV12 cell line had a high specific cofactor activity, equivalent to that of the 293-derived rHPS. A NaCl- elutable rHPS fraction (calcium nondependent) was isolated from the recombinant AV12-664 cell line, further purified, and found to have reduced activity, only 40% that of the calcium-dependent rHPS. The only observable difference in the calcium-dependent and nondependent rHPS molecules was in the content of gamma-carboxyglutamic acid (Gla); the calcium-dependent material contained approximately 10 mol Gla/mol protein whereas the calcium-nondependent material contained only approximately 8 mol Gla/mol of protein. In addition, the calcium- nondependent rHPS had reduced ability to interact with phospholipid vesicles as evidenced by an eightfold increase in the apparent kd. Our data demonstrate the isolation of rHPS with high specific activity, and show that a reduction in as few as two Gla residues dramatically decreases its functional cofactor activity for HPC, due to a reduction in ability to interact with the phospholipid bilayer. 相似文献
86.
87.
V.K. de Sá T.P. Rocha AL. Moreira F.A. Soares T. Takagaki L. Carvalho A.G. Nicholson V.L. Capelozzi 《Brazilian journal of medical and biological research》2015,48(11):1039-1047
We collected a series of 136 lung/bronchial and 56 matched lung parenchyma tissue
samples from patients who underwent lung/bronchial biopsies and presented invasive
carcinoma after lung surgery. The lung/bronchial samples included basal cell
hyperplasia, squamous metaplasia, moderate dysplasia, adenomatous hyperplasia, severe
dysplasia, squamous cell carcinoma and adenocarcinoma. Matched lung parenchyma tissue
samples included 25 squamous cell carcinomas and 31 adenocarcinomas.
Immunohistochemistry was performed to analyze for the distribution of hyaluronidase
(Hyal)-1 and −3, and hyaluronan synthases (HAS)-1, −2, and −3. Hyal-1 showed
significantly higher expression in basal cell hyperplasia than in moderate dysplasia
(P=0.01), atypical adenomatous hyperplasia (P=0.0001), or severe dysplasia (P=0.03).
Lower expression of Hyal-3 was found in atypical adenomatous hyperplasia than in
basal cell hyperplasia (P=0.01) or moderate dysplasia (P=0.02). HAS-2 was
significantly higher in severe dysplasia (P=0.002) and in squamous metaplasia
(P=0.04) compared with basal cell hyperplasia. HAS-3 was significantly expressed in
basal cell hyperplasia compared with atypical adenomatous hyperplasia (P=0.05) and
severe dysplasia (P=0.02). Lower expression of HAS-3 was found in severe dysplasia
compared with squamous metaplasia (P=0.01) and moderate dysplasia (P=0.01).
Epithelial Hyal-1 and −3 and HAS-1, −2, and −3 expressions were significantly higher
in pre-neoplastic lesions than in neoplastic lesions. Comparative Cox multivariate
analysis controlled by N stage and histologic tumor type showed that patients with
high HAS-3 expression in pre-neoplastic cells obtained by lung/bronchial biopsy
presented a significantly higher risk of death (HR=1.19; P=0.04). We concluded that
localization of Hyal and HAS in lung/bronchial pre-neoplastic and neoplastic lesions
was inversely related to malignancy, which implied that visualizing these factors
could be a useful diagnostic procedure for suspected lung cancer. Finalizing this
conclusion will require a wider study in a randomized and prospective trial. 相似文献
88.
Characterization of the potentiation effect of activin on human erythroid colony formation in vitro 总被引:1,自引:1,他引:1
Activin, also named FSH-releasing protein, was previously shown to induce hemoglobin accumulation in K562 cells and potentiate the proliferation and differentiation of CFU-E in human bone marrow cultures. Present studies indicate that the potentiation effect of activin is lineage specific. In addition to CFU-E, activin caused an increase in the colony formation of BFU-E from either bone marrow or peripheral blood. It had little effect on the colony formation of CFU- GM and the mixed colonies from CFU-GEMM. In serum-depleted culture, the effect of activin was shown to be dose-dependent with doses effective at picomolar concentrations. The potentiation effect of activin was exerted indirectly through mediation of both monocytes and T lymphocytes. Activin was also found to increase specifically the proportion of DNA-synthesizing erythroid progenitors from both bone marrow and peripheral blood. It had little effect on DNA synthesis in CFU-GM and in mitogen-stimulated lymphocytes. Addition of the monocytes or T lymphocytes to their respective depleted subpopulations of mononuclear cells reconstituted the enhancing effect of activin on the colony formation and DNA synthesis of erythroid progenitors. These results strongly suggest a specific role of activin in potentiating the proliferation and differentiation of erythroid progenitors in vitro. 相似文献
89.
90.
A. ALEEM S. AL AMOUDI S. AL‐MASHHADANI N. SIDDIQUI 《International journal of laboratory hematology》2005,27(6):395-398
Haemophagocytic syndrome (HPS) secondary to viral infections usually has a variable course and can be life‐threatening. We report a 53‐year‐old male patient who presented with fever, hepatosplenomegaly and pancytopenia. He had deranged liver function, abnormal clotting and markedly elevated serum ferritin. Bone marrow biopsy showed prominent haemophagocytosis. The patient was investigated thoroughly and found to have evidence of chronic hepatitis B‐virus (HBV) infection by serological tests and liver biopsy. Other conditions associated with HPS such as lymphoma, malignancy and other viral or bacterial infections were not present. The patient did not respond to steroids, intravenous immunoglobulins or cyclosporin but responded to etoposide and became apyrexial. He also became HBV negative on lamivudine. The patient died of infection later on but there was no evidence of recurrence of HPS. To the best of our knowledge this is the first case report of HPS associated with isolated HBV infection. 相似文献