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21.
血浆TPO水平变化与血小板减少疾病的关系 总被引:2,自引:0,他引:2
目的:探讨血浆血小板生成素(Thrombopoietin,TPO)水平变化与血小板减少疾病的关系。方法:采用多抗夹心酶联免疫吸附法对68例各种不同原因致血小板减少患者通过应用白介素-11(rhIL-11)来动态检测TPO水平,rhIL-11剂量为25μg/(kg.d),皮下注射,连用10天。结果:(1)急性白血病(Acute leukemia,AL)化疗后血小板减少患者TPO水平低于正常对照组;再生障碍性贫血(Aplastic anemia,AA)及骨髓增生异常综合征(Myelodysplastic syndrome,MDS)患者TPO水平高于正常对照组;原发性血小板减少性紫癜(Idiopathic thrombocytopenic purpura,ITP)及肝硬化(Liver cirrhosis)患者TPO水平与正常对照组无明显差异。而其中的白血病化疗后血小板减少患者和AA患者的骨髓巨核细胞数较TPO正常组显著降低。(2)上述疾病患者用rhIL-11有效者TPO水平趋于正常,无效或疗效欠佳者,则TPO无变化。有效者TPO水平与血小板计数呈负相关。结论:血浆TPO检测,有助于临床鉴别各种血小板减少疾病的病因,对血小板减少患者合理应用rhIL-11提供理论的依据。 相似文献
22.
Use of enzyme-linked immunosorbent assays with chimeric fusion proteins to titrate antibodies against Epstein-Barr virus nuclear antigen 1.
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N Inoue J Kuranari S Harada H Nakajima M Ohbayashi Y Nakamura N Miyasaka K Ezawa F Ban K Yanagi 《Journal of clinical microbiology》1992,30(6):1442-1448
Two new enzyme-linked immunosorbent assays (ELISAs) with chimeric fusion polypeptides for the detection of human antibodies specific to Epstein-Barr virus nuclear antigen 1 (EBNA-1) are described. One is an indirect ELISA with affinity-purified beta-galactosidase-EBNA-1 fusion protein as the antigen. The other is a "sandwich" assay based on the use of anti-beta-galactosidase antibody to capture beta-galactosidase-EBNA-1 fusion proteins in bacterial extracts. A good correlation was shown between antibody titers determined by the ELISA with the EBNA-1 fusion proteins and those determined by a conventional anticomplement immunofluorescence test which is being widely performed with Raji cells for the purpose of research and clinical diagnosis. The advantage of the ELISAs for seroepidemiologic studies on Epstein-Barr virus was demonstrated by sensitive detection of marginal immunoglobulin G antibody to the EBNA-1 domain in serum samples from patients with infectious mononucleosis. 相似文献
23.
Kojima M Nakamura S Ban S Inagaki M Sugihara S Yoshida K Masawa N 《Pathology, research and practice》2002,198(10):685-688
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT. 相似文献
24.
Naoaki Misawa Ban Mishu Allos Martin J. Blaser 《Journal of clinical microbiology》1998,36(12):3567-3573
Guillain-Barré syndrome (GBS), a neurologic disease characterized by acute paralysis, is frequently preceded by Campylobacter jejuni infection. Serotype O19 strains are overrepresented among GBS-associated C. jejuni isolates. We previously showed that all O19 strains tested were closely related to one another by randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism analyses. RAPD analysis demonstrated a 1.4-kb band in all O19 strains tested but in no non-O19 strains. We cloned this O19-specific band; nucleotide sequence analysis revealed a truncated open reading frame with significant homology to DNA gyrase subunit B (gyrB) of Helicobacter pylori. PCR using the random primer and a primer specific for gyrB showed that in non-O19 strains, the random primer did not recognize the downstream gyrB binding site. The regions flanking each of the random primer binding sites were amplified by degenerate PCR for further sequencing. Although the random primer had several mismatches with the downstream gyrB binding site, a single nucleotide polymorphism 6 bp upstream from the 3′ terminus was found to distinguish O19 and non-O19 strains. PCR using 3′-mismatched primers based on this polymorphism was designed to differentiate O19 strains from non-O19 strains. When a total of 42 (18 O19 and 24 non-O19) strains from five different countries were examined, O19 strains were distinguishable from non-O19 strains in each case. This PCR method should permit identification of O19 C. jejuni strains. 相似文献
25.
26.
Frelin AM Fontbonne JM Ban G Colin J Labalme M Batalla A Isambert A Vela A Leroux T 《Medical physics》2005,32(9):3000-3006
Radiation therapy accelerators require highly accurate dose deposition and the output must be monitored frequently and regularly. Ionization chambers are the primary tool for this control, but their size, their high voltage needed, and the correction needed for electrons make them unsuitable for use during patient treatment. We have developed a small (1-mm-diam and 1-mm-long active part), flexible, and water-equivalent dosimeter. It is suitable for photon and electron beams without corrections, and performs on line dose measurements. This detector is based on only one scintillating fiber and a CCD camera. A new signal processing is used to remove the effect of Cerenkov radiation background, which only requires a preliminary calibration. Central-axis depth-dose distribution comparisons have been achieved with standard ionization chambers, over a range from 8 to 25 MV photons and from 6 to 21 MeV electrons in order to validate this calibration. Results show a very good agreement, with less than 1% difference between the two detectors. 相似文献
27.
Previous studies showed that platelet adhesion to biomaterials from static suspensions was greatly increased by the adsorption of even very small amounts (<5 ng/cm2) of fibrinogen (Fg). In this study, the sensitivity of platelet adhesion to Fg was reexamined by measuring platelet adhesion under flow conditions. The role of adsorbed von Willebrand's factor (vWf) was also studied. Polyethylene (PE) tubing was preadsorbed with Fg, vWf, vWf-deficient plasma, and Fg-deficient plasma or serum with added Fg, and Fg adsorption measured with 125I Fg. Platelets in a red blood cell suspension were passed through the tubes at either low (50 s(-1)) or high (500 or 1000 s(-1)) shear rates and adhesion measured with an improved LDH assay. Adhesion from flowing suspensions measured after preadsorption with afibrinogenemic plasma or serum was very low, but increased greatly with addition of Fg. Less than 10 ng/cm2 of adsorbed Fg was enough to greatly enhance platelet adhesion. Adhesion at high shear was also strongly affected by vWf, as platelet adhesion at 500 s(-1) to PE preadsorbed with vWf-deficient plasma decreased by more than tenfold compared to adhesion at 50 s(-1), but platelet adhesion to PE preadsorbed with normal plasma increased about eightfold when shear rate was increased. The results show that very low amounts of adsorbed Fg are able to support platelet adhesion under shear flow. However, adsorbed vWf also appears to play an important cofactor role in platelet adhesion to biomaterials, as its presence greatly augments platelet adhesion under high shear. 相似文献
28.
An autopsy case of mitochondrial encephalomyopathy (MELAS) with special reference to extra-neuromuscular abnormalities. 总被引:3,自引:0,他引:3
An autopsy case of a 37-year-old man with mitochondrial encephalomyopathy is reported. Ragged-red fibers and crystalline inclusions in mitochondria were revealed by biopsy of the striated muscle of the patient. Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS) was diagnosed clinically. In addition to severe atrophy and degeneration of the generalized striated muscles and many foci of laminar necrosis of the cerebral cortex, the following abnormalities were observed: 1) hypertrophy of the myocardium, 2) fatty change of the liver, 3) focal sclerosis of the glomeruli and dilatation of the tubules of the kidneys, 4) hyalinous degeneration of the Langerhans' islands of the pancreas and 5) wavy change of the smooth muscle fibers of the muscularis propria of the gastrointestinal tract. We suggest that mitochondrial encephalomyopathy affects various organs and tissues, among which susceptibility of the muscular tissues--skeletal muscle, myocardium and smooth muscle--is high. 相似文献
29.
T. Ban S. Sada Y. Takahashi H. Sada T. Fujita 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(1):77-85
Summary The effects of atenolol (2–5 mmol/l), sotalol (1–2 mmol/l) and pamatolol (0.1–1 mmol/l), together with N-tertiary butyl phenoxypropanolamines with o-methyl (D-2T: 50–100 mol/l) m-methyl (D-3T: 50–100 mol/l) and p-methyl (D-4T:100–200 mol/l) group as well as with o,p-methyl groups (D-24T) (50–100 mol/l) on action potentials (APs) were investigated in isolated guinea-pig papillary muscles. All the drugs in these concentrations produced a concentration-dependent reduction of the maximum upstroke velocity (V
max). The reduction ofV
max in premature APs induced by stimuli interpolated between the basic driving rate of 0.25, 0.1 or 0.027 Hz decayed exponentially during diastolic intervals. The time constants of these decay processes for atenolol, pamatolol and sotalol ranged between 260–541 ms, those for D-3T and D-4T between 655–1,166 ms, and D-2T and D-24T between 1,565–1,931 ms. A drug which provided larger values caused the reduction ofV
max in a wider range of the frequency. With respect to the aryloxypropanolamine derivatives so far studied (Sada and Ban 1980, 1981 a, b; Sada et al. 1983) fairly good correlations were found as follows: between logn-octanol/water partition coefficient (logP) and ED20 at 0.25 Hz, ED30 at 1 and 4 Hz for 11–14 compounds; between logP and resting block, between molecular weight and A
o
c
i.e. the value extrapolated to the time of APD90 of the conditioning response relative to the predrugV
max value which may represent a fraction of channels blocked per AP for 100 mol/l of 20–22 compounds. With respect to 8 compounds with methyl substituents in the benzene ring or amine part the ortho methyl group makes a major contribution to increase the resting block and to increase log values. 相似文献
30.
为观察并了解东菱精纯克栓酶对荷瘤裸鼠全血Casson值的影响,采用锥板式粘度计对移植了胃癌和鼻咽癌的荷瘤裸鼠使用东菱精纯克栓酶前后的全血粘度进行检测,并采用线性回归的方法求出各组Casson粘度(CV)及Casson屈服值(CY)。结果显示,使用东菱精纯克栓酶后两组荷瘤裸鼠全血(CV)值皆明显下降(P<0.01);(CY)值在胃癌组明显下降(P<0.01),鼻咽癌组无明显变化(P>0.05)。结果表明,使用东菱精纯克栓酶对荷瘤裸鼠的血液流变学参数有明显改善,提示有可能将其应用于临床预防肿瘤转移及扩散。 相似文献