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101.
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103.
Yoshikuni Kudo Toru Egashira Fusako Takayama Yasumitsu Yamanaka Tatsuo Shimada 《Archives of toxicology》1993,67(7):502-509
To explain the mechanism of renal injury caused by liver ischemia-reperfusion, we investigated biochemical and morphological changes in the liver and kidney in rats. After reperfusion following 60 min of liver ischemia, numerous changes were found. The level of serum transaminases and lipid peroxide formation in the liver tissue increased significantly. Electron microscopic studies revealed that most of the hepatocytes had swollen mitochondria and clumping of the nuclear chromatin. The sinusoidal endothelium was disrupted and the sinusoidal lumen was filled with numerous erythrocytes. Blood endotoxin concentration, plasma lipid peroxide levels, and serum -glucuronidase activities were significantly higher than in the control group. Biochemical and morphological renal injury was also observed. Tissue lipid peroxide levels increased in both the kidney and the liver. Microscopic examination revealed damage to the renal tubules, including interstitial edema, dilatation of the lumen, and granular casts derived from necrotic cells in the proximal convoluted tubule. The levels of urinary N-acetyl--d-glucosaminidase (NAG) in the liver ischemia-reperfusion group were also higher than in the control group. These results suggest that the renal injury was caused by an increase in endotoxin, lipid peroxide, and lysosomal enzymes in the blood following the liver injury induced by the ischemia-reperfusion. 相似文献
104.
Ryuichi Fukuyama Yohko Murakawa Stanley I. Rapoport 《Molecular and chemical neuropathology / sponsored by the International Society for Neurochemistry and the World Federation of Neurology and research groups on neurochemistry and cerebrospinal fluid》1994,23(2-3):93-101
To understand the possible role of amyloid precursor protein (APP) in human lymphocytes, and the regulation of APP gene expression in this cell type, we determined levels of cellular APP protein and of mRNA in human T-cell-derived Jurkat cells that were treated with lectin, phorbol ester, and calcium ionophore. We also related these levels to cell aggregation and adhesion. Cell-cell aggregation and cell-plastic adhesion were observed over a 24-h period after incubating cells for 2 h with phytohemagglutinin or phorbol myristate acetate. Cells treated with a calcium ionophore showed no aggregation or adhesion. Western blots indicated no obvious alteration in the level of cellular APP with different treatments. Northern blots showed a significant transient increase of APP mRNA after incubation with the calcium ionophore, whereas phorbol ester treatment showed a slight increase of APP mRNA. We analyzed the level of APP mRNA in human peripheral T cells which had been separated from peripheral lymphocytes. The level increased transiently by up to threefold after treatment with calcium ionophore plus phorbol esters. These data suggest that cell-cell aggregation and cell-matrix adhesion by human lymphocytes are not associated with an increased level of cellular APP protein or of mRNA. 相似文献
105.
Tomoaki Yuhi Akihiko Wada Ryuichi Yamamoto Masanobu Urabe Hiromi Niina Futoshi Izumi Toshihiko Yanagital 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(2):209-212
We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced 22Na influx when given alone, but increases the influx of 22Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [3H]PbTx-3 binding in bovine adrenal chromaffin cells. [3H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (Kd) of 32.0±4.9 nmol/1 and a maximum binding capacity Bmax of 6.2 ± 1.2 pmol/4 × 106 cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [3H]PbTx-3 binding with an IC50 of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [3H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells.
Correspondence to: A. Wada at the above address 相似文献
106.
107.
K. Eguchi J. Kabe S. Kudo K. Mano H. Morinari K. Nakada K. Noda Y. Saito T. Tanaka T. Uzawa K. Watanabe N. Saijo 《Cancer chemotherapy and pharmacology》1994,34(1):37-43
To assess the feasibility and efficacy of rhGM-CSF in ameliorating chemotherapy-induced leukopenia in patients with advanced non-small-cell lung cancer, we conducted a double-blind placebo controlled phase III study in a multicenter setting. Patients were eligible if they had cytologically or histologically proven cancer, no prior chemotherapy, stage IIIB or IV disease, an Eastern Cooperativve Oncology Group (ECOG) performance status of 0–2, an age of less than 76 years, and no symptomatic brain metastasis, disseminated bone metastasis, or previous vertebral/pelvic irradiation. The chemotherapy regimen consisted of mitomycin given at 8 mg/m2 on day 1, cisplatin given at 100 mg/m2 on day 1, and vindesine given at 3 mg/m2 i.v. on days 1 and 8 (MVP). If the granulocyte nadir count recorded after the first cycle of MVP was less than 1,000/mm3, patients were randomly assigned to receive recombinant human granulocyte-macrophage colonystimulating factor (rhGM-CSF) or placebo during the second cycle of MVP. The dose of rhGM-CSF was 125 g/m2 given daily s.c. for 14 consecutive days starting on day 2. Of the 52 patients enrolled, 45 were evaluable. The nadir of granulocytes was significantly lower in the placebo group (P=0.007). The period during which the granulocyte count was less than 1,000/mm3 was significantly longer in the placebo group (median, 6 vs 10 days;P=0.04). The incidence of adverse effects related to rhGM-CSF, such as fever (38°C) and skin rash, was significantly higher in the rhGM-CSF group (P=0.011). The rate of response to chemotherapy did not significantly differ between the two groups. In conclusion, rhGM-CSF reduced the duration of chemotherapy-induced granulocytopenia. The clinical usefulness of this agent may be deminished because of the adverse effects encountered when it is used in combination with a moderately myelotoxic chemotherapy regimen.Institutions of the BI 71.018 Cooperative Study Group, National Cancer Center Research Institute (N. Saijo, Chairman): Douai Memorial Hospital (Y. Sano), Kanagawa Prefectural Cancer Center (K. Noda), Kantou Teishin Hospital (T. Uzawa), National Medical Center (J. Kabe), Shizuoka Prefectural General Hospital (H. Etou), Teikyo University (K. Mano), Tochigi Prefectural Cancer Center (Y. Saito), Tokyo Geriatric Medical Center (A. Kida), Tokyo Teishin Hospital (T. Morinari), Tokyo Metropolitan Komagome Hospital (S. Kudo), Tokyo Metropolitan Hiroo Hospital (A. Fujikawa), Toranomon Hospital (K. Nakada), Yokohama Municipal Hospital (K. Watanabe), National Cancer Center Central Hospital (K. Eguchi) 相似文献
108.
Motonobu Kameyama Kiichi Ishiwata Yuji Tsurumi Jun Itoh Kiyotaka Sato Ryuichi Katakura Takashi Yoshimoto Jun Hatazawa Masatoshi Ito Tatsuo Ido 《Journal of neuro-oncology》1995,23(1):53-61
Summary Positron emission tomography was used to investigate the metabolism of nucleic acids by18F-fluoro-2-deoxyuridine (18F-FUdR) in 22 patients with gliomas. Sixteen cases of high grade glioma clearly demonstrated a region of high activity with a differential absorption rate (DAR) of 0.64 ± 0.34. Six cases of low grade glioma failed to reveal a positive image of the tumor and the DAR in tumor was 0.21 ± 0.042 (p < 0.01). This PET-18F-FUdR study succeeded in differentiating high and low grade gliomas from the view point of nucleic acid metabolism. 相似文献
109.
The gravity model, a method for analyzing transportation distribution in transportation engineering, was used to explain patient
trips between ten health service regions in a Japanese prefecture. The OD (Origin-Destination) tables were constructed with
zoning by regions, distinguishing between out- and inpatients. The observed trips were determined from the data of a survey
conducted in 1992 that reported the locations of patient residences and chosen medical facilities.
The base values used in the model calculations were the population size of each region and the road distance between the centers
of regions. Problems of intrazonal trip were avoided by setting a mean intrazonal movement distance.
This model was calibrated by the linear regression method with simultaneous validation by the index of correlation coefficients.
The model was found to accurately simulate the effect of distance on the choice of medical facilities and the differences
between the characteristics of in- and out-patients. The population value in use showed the relation not only with demand
but also the supply of clinical services. It was suggested that the model presented here was useful in the allocation of medical
resources and would help explain the relationship between suppliers and consumers of medical services. 相似文献
110.
Kuba H Sato N Uchiyama A Nakafusa Y Mibu R Yoshida K Kuroiwa K Tanaka M 《Surgery today》1999,29(4):375-377
We herein describe a patient with mediastinal lymph node metastases which occurred after both a primary sigmoid colon cancer
and metachronous ovarian metastasis had been resected. The most likely route of metastases to the mediastinum in this case
is the paravertebral venous plexus probably connected to the ovarian metastasis, or so-called remetastasis. This case illustrates
that the mediastinum is thus a possible metastatic site in patients with colon cancer. Surgeons should therefore pay attention
to the mediastinum as well as the lung fields when checking chest X-ray films during a follow-up of patients after a resection
of colon cancer. 相似文献