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41.
Imamura M Seki T Kunieda K Tamai T Nishimura A Inoue K Harada K 《International journal of oncology》1997,10(5):961-964
We have developed a new type of drug delivery system (DDS) comprising a complex of porous hydroxyapatite (HAP) with the anticancer drug doxorubicin hydrochloride (DOX) and the glutathione inhibitor buthionine sulfoximine (BSO) (DOX and BSO-HAP complex). We then studied the antitumour effect of DOX and BSO-HAP combined with 44 degrees C hyperthermia for 40 min. It was found that in mice this combined treatment suppressed the growth of sarcoma 180 in terms of tumour volume to 36% in comparison viith mice given plain HAP, and was more effective than HAP + hyperthermia or DOX- and BSO-HAP. These results were also confirmed by histological observation. 相似文献
42.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
43.
Kuge Y Tsukamoto E Katoh C Seki K Ohkura K Ohmiya Y Nishijima K Tanaka A Sasaki M Tamaki N 《Kaku igaku. The Japanese journal of nuclear medicine》1999,36(8):873-878
We synthesized 18F-FDG by using an automated synthetic apparatus "FDG MicroLab" (GE Medical Systems) which produces 18F-FDG by a solid phase 18F-fluorination. Its quality and reproducibility were evaluated in order to assess feasibility of the apparatus for routine clinical production of 18F-FDG. For 5 consecutive 18F-FDG synthesis, target irradiation was carried out at 15 microA for 60 min. 18F-FDG was obtained in 50 min after EOB with an end-of-synthesis yield of 9.34 +/- 1.06 GBq. Radiochemical yield and radiochemical purity were 47 +/- 3% (decay corrected) and 98.0 +/- 0.5%, respectively. Other several quality control parameters tested conformed with "Standards of Compounds Labeled with Positron Nuclides" (RADIOISOTOPES, 44, 1995). Thus, the automated synthetic apparatus "FDG MicroLab" has proven to stably produce 18F-FDG with high yield and high purity. The apparatus is feasible for routine clinical production of 18F-FDG. 相似文献
44.
OBJECTIVE: To assess the factors affecting patency of the hepatic artery during hepatic arterial infusion chemotherapy (HAIC) with an implantable port system inserted percutaneously. PATIENTS AND METHODS: Ninety patients with malignant hepatic tumours were given HAIC using percutaneous catheter placement. An end-hole catheter was inserted into the hepatic artery (conventional method) in 41 patients. An end-closed and side-hole catheter was used in 49 patients, in which the catheter tip was fixed in the gastroduodenal artery and the side hole was placed in the common hepatic artery (fixed catheter-tip method). The patency of the hepatic artery was evaluated with computed tomography (CT) arteriography using the implantable port system and angiography. Then, the factors affecting hepatic arterial patency were analysed. RESULTS: Hepatic arterial occlusion was observed in 15 patients (17%). The overall patency of the hepatic artery was 86.9%, 78.4% and 51.5% at 6 months, 1 year and 2 years, respectively. The patency rate of the hepatic artery was significantly higher in patients with catheter placement using fixed catheter-tip method than those using conventional method (P = 0.01), and in patients without transcatheter arterial chemoembolization (TACE) prior to catheter placement than those with prior TACE (P = 0.01). When the variables affecting patency of the hepatic artery were studied together by multivariate analyses, the important factors were the method of catheter placement and the presence or absence of prior TACE. CONCLUSION: We consider that it is important for long-term patency of the hepatic artery during HAIC to use fixed catheter-tip method for percutaneous catheter placement instead of conventional method, and to select patients without prior TACE. 相似文献
45.
46.
Arikawa K Mizuno S Scholten DG Kinoshita M Seki T Kitamoto J Stavenga DG 《Vision research》1999,39(1):1-8
The distal photoreceptors in the tiered retina of Papilio exhibit different spectral sensitivities. There are at least two types of short-wavelength sensitive receptors: an ultraviolet receptor with a normal spectral shape and a violet receptor with a very narrow spectral bandwidth. Furthermore, a blue receptor, a double-peaked green receptor and a single-peaked green receptor exist. The violet receptor and single-peaked green receptor are only found in ommatidia that fluoresce under ultraviolet illumination. About 28% of the ommatidia in the ventral half of the retina exhibit the UV-induced fluorescence. The fluorescence originates from an ultraviolet-absorbing pigment, located in the most distal 70 microns of the ommatidium, that acts as an absorption filter, both for a UV visual pigment, causing the narrow spectral sensitivity of the violet receptor, and for a green visual pigment, causing a single-peaked green receptor. 相似文献
47.
Increased levels of urinary interleukin-6 in Kawasaki disease 总被引:4,自引:0,他引:4
K. Ohta A. Seno N. Shintani E. Kato A. Yachie H. Seki T. Miyawaki N. Taniguchi 《European journal of pediatrics》1993,152(8):647-649
Kawasaki disease (KD) often presents with abnormal urinary findings, such as aseptic pyuria, mild proteinuria and microscopic haematuria. In this study, we measured urinary interleukin-6 (IL-6) by a sensitive sandwich ELISA assay using mouse monoclonal antibodies against recombinant IL-6 to elucidate the role of IL-6 in the pathogenesis of renal lesions in KD. Serum IL-6 levels were increased in acute KD as well as in febrile controls. Importantly, urinary IL-6 levels were consistently elevated in patients with acute KD, but much lower in febrile controls. Urinary IL-6 levels returned steadily to normal during the convalescent phase. In addition to IL-6, urinary levels ofN-acetyl--d-glucosaminidase (NAG) and 2-microglobulin (2-mg) were also elevated during the acute phase of this disease. Eosinophils and macrophages were identifiable in urinary sediments from these patients. The increased levels of urinary IL-6 in combination with increased NAG and 2-mg seemed to suggest the presence of certain renal parenchymal lesions with cellular infiltration during the acute phase of the disease. IL-6 may serve as clinically useful parameter for the detection and monitoring of the renal involvement in KD. 相似文献
48.
Seki Y Umezu H Usui M Kumakawa K Kumagai F Komatsuzaki A Hitselberger WE 《Neurologia medico-chirurgica》2000,40(10):524-527
A 25-year-old male with neurofibromatosis type 2 had hearing restored with an auditory brainstem implant (ABI) after removal of an acoustic schwannoma. The ABI allows the patient to discern many different environment sounds and is a significant adjunct to lip-reading, enabling conversation with people who have clear pronunciation without the necessity for writing. 相似文献
49.
An experimental study of the effects of nerve root retraction on the posterior ramus 总被引:7,自引:0,他引:7
STUDY DESIGN: The histologic and ultrastructural changes in the posterior ramus after posterior lumbar surgery were studied in rabbits. OBJECTIVE: To investigate the structural changes in the posterior ramus after posterior lumbar surgery that may cause injury to the posterior ramus after the procedure. SUMMARY OF BACKGROUND DATA: Investigators in previous studies have pointed out that low back discomfort after lumbar discectomy relates to neurogenic changes and/or myogenic changes of paravertebral muscle. However, no previous study has demonstrated the effects of excessive nerve root retraction on spinal posterior rami. METHODS: Eighteen male Japanese White rabbits were used. The posterior ramus arising from the S1 nerve root was examined after exposure of the lamina only, fenestration, or retraction of the S1 nerve root, with light microscopy and transmission electron microscopy at 2, 4, and 6 weeks after the procedure. Results were compared with a those in control specimens that did not undergo the procedure. RESULTS: In the exposed group, no distinct difference was found compared with the control specimen. In the fenestration group, especially at 6 weeks, some attenuation and splitting of myelin sheaths was observed. In the retraction group, the structural alteration was most severe. Even at 2 weeks, fragmentation of many myelin sheaths was detected. Examination of specimens by electron microscopy indicated phagocytosis of myelinated fibers at 4 and 6 weeks. CONCLUSIONS: Findings showed that posterior lumbar procedures, including retraction of paravertebral muscle, fenestration of the lamina, and retraction of the nerve root affect the posterior ramus. Excessive retraction of the nerve root has an especially disastrous effect on the posterior ramus. Such a violent maneuver within the spinal canal must be avoided. 相似文献
50.
In patients with reduced respiratory function, lung resection is associated with high risk because separate ventilation is generally needed for safe management. For patients with end-stage emphysema, intraoperative respiratory management is important and particularly difficult because neither incomplete oxygenation nor selective ventilation can be performed, so the operation may be interrupted. In this study, we assess the effectiveness of the percutaneous cardiopulmonary support (PCPS) system for lung volume reduction surgery in patients with severe hypercapnia (arterial carbon dioxide tension >50 mm Hg) and discuss the significance of PCPS for patients who are beyond the standard criteria for lung volume reduction surgery (LVRS). We studied 3 patients with severe hypercapnia due to emphysema who underwent volume reduction surgery. One patient was previously treated surgically for contralateral pneumothorax. All patients had a severe smoking history and were suspected to have fragile lungs. During the operation. PCPS provided sufficient support flow. Intraoperative management using PCPS was easy, and no severe complications were observed. One patient exhibited severe hemodynamic deterioration on postoperative Day 15. Other patients' PaCO2 improved postoperatively. One had a calcification of a femoral artery, but there was no trouble inserting a cannula. Bilateral or unilateral volume reduction surgery was performed under PCPS in patients with end-stage emphysema. We conclude that PCPS is an adjunct to LVRS, useful for intraoperative management of some patients with severe hypercapnea, and the LVRS indications can be extended. 相似文献