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61.
Ura Hitoshi; Denda Ayumi; Yokose Yoshihiko; Tsutsumi Masahiro; Konishi Yoichi 《Carcinogenesis》1987,8(11):1595-1600
The effects of dietary vitamin E (VE) on the steps of hepatocarcinogenesis,the induction and growth of -glutamyltranspeptidase (GGT)-positivefoci and their evolution into persistent nodules, were analyzedin the liver of rats treated with diethylnitrosamine (DEN).The induction of GGT-positive foci was inhibited by a diet containing0.361.5% VE given after initiation with 200 mg/kg bodyweight (b.w.) DEN for 6 weeks with partial hepatectomy (PH)on week 3. The numbers and areas of GGT-positive foci were enhancedby diets containing 036 and 0.72% VE, given for 1 week afterinitiation with 10 mg/kg b.w. DEN and PH, followed by selectionby 0.02/ 2-acetylaminofluorene (AAF) and carbon tetrachloride(CCl4), but these were not enhanced by a diet containing 1.5%VE. Remodeling of hyperplastic nodules was not affected by thediet containing 0.72% VE given after initiation with DEN andselection for 12 weeks. The staining characteristics of GGTwere different between remodeling and persistent nodules, exceptfor those of the glutathione-S-transferase placental form (GST-P).The results obtained suggest that VE could prevent the veryearly events during hepatocarcinogenesis, the induction of phenotypicallyaltered foci, but could no longer affect the later stages, theevolution of foci into persistent nodules. 相似文献
62.
63.
Kouji Katsura Yoshihiko Soga Sadatomo Zenda Hiromi Nishi Marie Soga Masatoshi Usubuchi Sachiyo Mitsunaga Ken Tomizuka Tetsuhito Konishi Wakako Yatsuoka Takao Ueno Tadanobu Aragaki Takafumi Hayashi 《Journal of radiation research》2021,62(2):374
The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals. 相似文献
64.
Kawabata Kenji Kondo Mayumi Watanabe Yoshihiko Takakura Yoshinobu Hashida Mitsuru 《Pharmaceutical research》1997,14(4):483-485
Purpose. The intestinal epithelium is considered to be a feasible target for somatic gene therapy. To this end, Caco-2 cells derived from human colon carcinoma were transfected with a mouse interferon- (IFN-) expression vector and several stable sublines were established; this hetero-specific cytokine allows unexpected cellular effects to be avoided. Using the highest mouse IFN--producing sublines, the mode of IFN secretion was examined.
Methods. The secretion polarity of mouse IFN- in its gene-transduced Caco-2 sublines was studied in a bicameral culture system in which the chambers were separated by microporous filters.
Results. Mouse IFN- was secreted to the same extent from both apical and basolateral surfaces of the transduced cells regardless of cell aging.
Conclusions. These results suggest that in the intestinal epithelium exogenous gene products such as IFNs can be delivered to both the luminal and blood sides in vivo. Thus, the intestinal epithelium may be suitable for systemic and local delivery of therapeutic proteins by gene transfer. 相似文献
65.
We evaluated three solutions used for preserving lungs, namely, University of Wisconsin (UW), Euro-Collins (E-C), and low potassium dextran (LPD), by measuring the high energy phosphates in the preserved lung tissue. The left lungs of Sprague-Dawley rats were excised and flushed with 5 ml of one of the solutions at 10°C through the pulmonary artery, after which they were deflated and immersed in the solution at 10°C for 24 h. The tissue adenosine triphosphate (ATP) concentration in mol/g tissue wet weight after 24 h of storage was 2.55 ± 0.48 (n = 7) in the UW lungs, 1.98 ± 0.25 (n = 6) in the E-C lungs, and 1.53 ± 0.32 (n = 4) in the LPD lungs, being significantly higher in the UW lungs than in either the E-C or LPD lungs (P < 0.05). The histopathological findings of the E-C lungs were more deteriorated, with marked interstitial edema, septal hypertrophy, and perivascular hyaline degeneration, than either the UW or LPD lungs. Thus, the findings of this study indicate the superiority of UW solution for lung preservation. 相似文献
66.
We report on a case of multiple bone metastasis and disseminated intravascular coagulation (DIG) in a 49-year-old Japanese man. He underwent total gastrectomy for advanced gastric cancer in July 1992, He was diagnosed as a case of multiple bone metastasis in August 1993. Severe anemia, thrombocytopenia, and elevated fibrinogen degradative products were indicative of DIG. He was treated with sequential i.v. administration of methotrexate (MTX) and 5-fluorouracil (5-FU) and continuous i.v. infusion of heparin and gabexate mesilate. After two weeks of treatment with MTX combined with 5-FU, the findings of DIC disappeared and his general condition improved dramatically. 相似文献
67.
Baba H Maehara Y Takeuchi H Inutsuka S Yamamoto M Endo K Sugimachi K 《International journal of oncology》1994,4(2):329-333
In an attempts to increase the antitumor effect and to reduce normal tissue toxicity, the combined cytotoxic effect of cis-Diamminedichloroplatinum (II) (CDDP) and cis-diammine(1,1-cyclobutane dicarboxylate) platinum (II) (CBDCA) was investigated using HeLa and colon 26 cell lines and the combination index (CI). Cytotoxicity of the combination of CDDP and CBDCA on 27 surgically resected specimens of human gastric and colorectal adenocarcinomas was also evaluated using the in vitro succinate dehydrogenase inhibition (SDI) test. The CI values varied with the dose ratio examined (1:1-1:6) of CDDP and CBDCA, with findings that CI<1, synergy, was obtained at fraction affected (Fa)>0.75 for HeLa cells and at Fa<0.9 for colon 26 cells in cases of a dose ratio of 1:1 to 1:2. Of all 27 clinical human adenocarcinomas, the succinate dehydrogenase (SD) activity was significantly lower in cancer cells concomitantly exposed to both CDDP and CBDCA than in those exposed to either drug alone. These positive effects of a combination of two platinum analogues on human malignant tissues have heretofore not been reported, which would warrant the clinical application of this combination for human malignant tumors. 相似文献
68.
T Nariai R Suzuki K Hirakawa T Maehara K Ishii M Senda 《AJNR. American journal of neuroradiology》1995,16(3):563
PURPOSETo determine the value of the acetazolamide challenge test with stable xenon-enhanced CT (Xe CT) for making therapeutic decisions in patients with chronic cerebrovascular disease.METHODSWe compared the Xe CT-measured acetazolamide response with various measures obtained by positron emission tomography. We performed both a positron emission tomographic scan and a Xe CT study in 11 patients with chronic cerebral ischemic diseases within a 1-week interval. An increase of cerebral blood flow after injection of acetazolamide was expressed as delta AT. Regional cerebral blood flow, cerebral oxygen metabolism, oxygen extraction fraction, and cerebral blood volume were measured with oxygen-15-labeled gases by positron emission tomography.RESULTSIn low-cerebral blood flow regions, decreased delta AT was accompanied by a significant elevation of oxygen extraction fraction and cerebral blood volume, compared with oxygen extraction fraction and cerebral blood volume in regions of normal delta AT. Plotting of regional data indicated that delta was significantly dependent on oxygen extraction fraction and cerebral blood volume. The area of decreased vascular reserve determined by the Xe CT image corresponded to the area of "misery perfusion" determined by positron emission tomography.CONCLUSIONThe acetazolamide challenge test with Xe CT may offer an alternative to positron-emission tomography in detecting lesions with elevated oxygen extraction fraction and cerebral blood volume (misery perfusion) that result from chronic hemodynamic stress. 相似文献
69.
Inoue Y Katayama N Yoshioka N Yoshikawa K Kashima M Shimizu T Tsukune Y Ohtomo K 《Annals of nuclear medicine》1999,13(6):453-456
The aim of this study was to evaluate breast parenchymal activity on scintimammography with bone-seeking agents and 99mTc-MIBI. Scintimammography was performed with bone-seeking agents in 61 patients and with 99mTc-MIBI in 33 patients. Activity in the breast parenchyma contralateral to the suspected lesion was visually assessed by two independent observers. Increased breast parenchymal activity was shown in 19 of 61 patients examined with bone-seeking agents, while it was demonstrated in only two of 33 patients examined with 99mTc-MIBI. Breast parenchymal activity of bone-seeking agents was higher in patients aged 50 years or younger than in those older than 50. Increased parenchymal activity of bone-seeking agents may disturb visualization of primary breast cancer especially in relatively young patients. Low parenchymal activity is suggested to be a favorable characteristic of 99mTc-MIBI as a scintimammographic agent. 相似文献
70.
The results of surgical treatment for a ruptured type B aortic dissection remain far from satisfactory. It is believed that
additional perfusion from the right axillary artery might be more beneficial than perfusion from only the femoral artery during
surgery for a ruptured thoracic aneurysm. The right axillary perfusion is more likely to perfuse the vital organs proximal
to the ruptured area, and thus avoid retrograde emboli. In addition, if the open proximal method is performed, then the right
axillary perfusion is able to facilitate the evacuation of air from the aortic lumen. We present herein the case of a patient
in whom a ruptured type B acute aortic dissection was successfully treated by applying right axillary perfusion through a
left thoracotomy. 相似文献