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91.
Seo J Lee YG Kim SD Cha CJ Ahn JH Hur HG 《Archives of environmental contamination and toxicology》2005,48(3):323-328
Fungi (Cunninghamella elegans ATCC 9245, Mucor ramannianus R-56, Aspergillus niger VKMF-1119, and Phanerochaete chrysosporium BKMF-1767) were tested to elucidate the biologic fate of the topical insect repellent N,N-diethyl-m-toluamide (DEET). The elution profile obtained from analysis by high-pressure liquid chromatography equipped with a reverse-phase C-18 column, showed that three peaks occurred after incubation of C. elegans, with which 1 mM DEET was combined as a final concentration. The peaks were not detected in the control experiments with either DEET alone or tested fungus alone. The metabolites produced by C. elegans exhibited a molecular mass of 207 with a fragment ion (m/z) at 135, a molecular mass of 179 with an m/z at 135, and a molecular mass of 163 with an m/z at 119, all of which correspond to N,N-diethyl-m-toluamide-N-oxide, N-ethyl-m-toluamide-N-oxide, and N-ethyl-m-toluamide, respectively. M. ramannianus R-56 also produced N, N-diethyl-m-toluamide-N-oxide and N-ethyl-m-toluamide but did not produce N-ethyl-m-toluamide-N-oxide. For the biologic toxicity test with DEET and its metabolites, the freshwater zooplankton Daphnia magna was used. The biologic sensitivity in decreasing order was DEET > N-ethyl-m-toluamide > N,N-diethyl-m-toluamide-N-oxide. Although DEET and its fungal metabolites showed relatively low mortality compared with other insecticides, the toxicity was increased at longer exposure periods. These are the first reports of the metabolism of DEET by fungi and of the biologic toxicity of DEET and its fungal metabolites to the freshwater zooplankton D. magna. 相似文献
92.
BACKGROUND: Aneurysms arising from the proximal anterior cerebral artery (ACA) are quite rare. Here, we report upon such a case of aneurysms located at the proximal ACA and anterior communicating artery associated with middle cerebral artery (MCA) aplasia. CASE DESCRIPTION: A 64-year-old woman complained of severe headache. Brain computed tomography scans demonstrated acute subarachnoid hemorrhage. Angiograms showed 2 aneurysms located at the anterior communicating artery and proximal ACA, but did not show an MCA shadow on the lesion side. Instead, multiple collateral vessels ran toward the sylvian fissure and supplied the MCA territory, together with hypertrophied perforating branches. The operative findings confirmed that the cordlike rudimentary MCA had no internal blood flow. The 2 aneurysms were secured by neck clipping. CONCLUSION: The combined effects of these anomalies on the hemodynamic equilibrium of the arteries and the genesis of the aneurysms are noteworthy. 相似文献
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Tailgut cyst is a rare congenital presacral lesion and is believed to arise from the persistent remnants of the postanal gut. Malignancy occurring in a tailgut cyst is extremely rare, and to our knowledge only 5 cases of carcinoid tumor arising in a tailgut cyst have been reported in the literature to date. We report a sixth case of carcinoid tumor arising in a tailgut cyst. The patient was a 41-year-old woman who presented with perianal pain. Sigmoidoscopy showed a 2-cm submucosal mass located 4 cm above the anal verge. The mass was a multilocular cyst with gray-tan solid portions. The cyst was lined by ciliated columnar, squamous, and transitional epithelia with small foci of carcinoid tumor in the cystic wall. The carcinoid tumor showed a trabecular growth pattern with uniform oval or round cells containing fine chromatin and positive immunoreactivity for chromogranin, synaptophysin, and cytokeratin. This case was unique because the tumor occurred at the anorectal junction, not in the retrorectal space, and unlike previously reported cases showed aggressive behavior and distant metastases. 相似文献
96.
We report two cases that showed erroneous white blood cell differential counts by automated cell counters. Each case showed an interesting discrepancy of differential count between cell counters, and marked pseudobasophilia was observed by one of the two counters. The first patient was a 44-year-old female who suffered from multiple myeloma for more than one and a half years. Increased myeloma cells (43%) in peripheral blood were counted as basophils by the ADVIA 120, and as monocytes by SE-9000, respectively. The second patient was a 72-year-old female diagnosed as having chronic myelomonocytic leukemia. Dysgranulopoietic neutrophils (50%) and monocytes (31%) were increased in the peripheral blood. Dysgranulopoietic neutrophils were counted as basophils by STKS. In contrast, about half of the increased monocytes were counted as neutrophils by the ADVIA 120. These interesting findings highlight the importance of microscopic examination of the blood film in routine laboratory practice, and automated cell counters, especially for the hematologic patients, cannot completely substitute for it. These results also imply that at least some subpopulations with different membrane or cytoplasmic properties may exist even in the similarly classified cells. 相似文献
97.
Brodie C Steinhart R Kazimirsky G Rubinfeld H Hyman T Ayres JN Hur GM Toth A Yang D Garfield SH Stone JC Blumberg PM 《Molecular pharmacology》2004,66(1):76-84
RasGRP is a family of guanine nucleotide exchange factors that activate small GTPases and contain a C1 domain similar to the one present in protein kinase C (PKC). In this study, we examined the interaction of RasGRP3 and PKC in response to the phorbol ester PMA. In Chinese hamster ovary or LN-229 cells heterologously expressing RasGRP3, phorbol 12-myristate 13-acetate (PMA) induced translocation of RasGRP3 to the perinuclear region and a decrease in the electrophoretic mobility of RasGRP3. The mobility shift was associated with phosphorylation of RasGRP3 on serine residues and seemed to be PKCdelta-dependent because it was blocked by the PKCdelta inhibitor rottlerin as well as by a PKCdelta kinase-dead mutant. Using coimmunoprecipitation, we found that PMA induced the physical association of RasGRP3 with PKCdelta and, using in situ methods, we showed colocalization of PKCdelta and RasGRP3 in the perinuclear region. PKCdelta phosphorylated RasGRP3 in vitro. Previous studies suggest that ectopic expression of RasGRP3 increases activation of Erk1/2. We found that overexpression of either PKCdelta or RasGRP3 increased the activation of Erk1/2 by PMA. In contrast, coexpression of PKCdelta and RasGRP3 yielded a level of phosphorylation of Erk1/2 similar to that of control vector cells. Our results suggest that PKCdelta may act as an upstream kinase associating with and phosphorylating RasGRP3 in response to PMA. The interaction between RasGRP3 and PKCdelta points to the existence of complex cross-talk between various members of the phorbol ester receptors which can have important impact on major signal transduction pathways and cellular processes induced by phorbol esters or DAG 相似文献
98.
Mineralogical and chemical changes in pyrite after traditional processing for use in medicines 总被引:1,自引:0,他引:1
Pyrite has been the most commonly used medicinal mineral, and its toxicity was reduced by traditional processing operations including heating and quenching in vinegar. To verify the scientific effects of this process, pyrite was processed at temperatures up to 850 degrees C and through as many as five processing cycles. A metal extraction test was carried out from the processed pyrites on the assumption that pyrite medicines with the lowest toxic metal content would be most desirable. Increasing temperature and the number of processing cycles promoted phase change of pyrite to hematite, reduction of toxic metals in pyrite and their concentrations in the extraction solutions. However, the relationships between variations in extracted elements and the number of processing cycles at the same processing temperature were not clearly defined. Heating temperature is more important than the number of processing cycles for effective processing, and pyrite should be processed at the highest possible temperature in order to diminish highly toxic metals such as As and Pb. 相似文献
99.
Aksoy U Erbay A Akisu C Apa H Ozkoç S Oztürk S 《The Turkish journal of pediatrics》2003,45(2):129-132
Stool specimens taken from 50 children with malignancy and from 92 healthy children were investigated for intestinal parasites, using the modified formol ethyl acetate concentration method, and native-lugol, trichrome and Kinyoun acid-fast stain methods. Thirty-eight (76.0%) of the 50 patients had lymphoma or leukemia and were considered immunosuppressed. Several different parasites were found in 21 (42.0%) of the 50 patients with malignancy and in 16 (47.3%) of the 38 patients with immune deficiency compared to in only 16 (17.3%) of the 92 healthy children. The incidence of parasites in patients with malignancy or immunosuppression was significantly higher than in the healthy control group (p<0.01, p<0.01). 相似文献
100.
Matrix metalloproteinase-2, membranous type 1 matrix metalloproteinase,and tissue inhibitor of metalloproteinase-2 expression in ectopic and eutopic endometrium 总被引:33,自引:0,他引:33
OBJECTIVE: To investigate expression of matrix metalloproteinase-2 (MMP-2), membranous type 1 matrix metalloproteinase (MT1-MMP), and tissue inhibitor of metalloproteinase-2 (TIMP-2) in ectopic and eutopic endometrium from women with and without endometriosis throughout the menstrual cycle. DESIGN: Molecular studies in human tissue. SETTING: Reproductive immunology laboratory of a university medical center. PATIENT(S): Fifty-three premenopausal woman (23 with endometriosis and 30 without endometriosis) undergoing laparoscopic surgery. Endometrium and ectopic endometriosis tissue were obtained at the time of surgery. MAIN OUTCOME MEASURE(S): Messenger RNA and protein expression from eutopic and ectopic endometrium was analyzed by using quantitative competitive polymerase chain reaction, zymography, and Western blot assay. RESULT(S): Uterine endometrium from women with endometriosis expressed higher levels of MMP-2 and MT1-MMP and lower levels of TIMP-2 than did endometrium from normal women. CONCLUSION(S): Eutopic endometrium from patients with endometriosis may be more invasive and prone to peritoneal implantation because of greater expression of MMP-2 and MT1-MMP and lower expression of TIMP-2 messenger RNA, compared with endometrium from women without endometriosis. Thus, increased proteolytic activity may help to explain the invasive factors that result in endometriosis. 相似文献