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101.
Multiple-sited (heterotopic) pregnancy after in vitro fertilization and gamete intrafallopian transfer 总被引:1,自引:0,他引:1
D Molloy W Deambrosis D Keeping J Hynes K Harrison J Hennessey 《Fertility and sterility》1990,53(6):1068-1071
Pregnancies occurring simultaneously in different body sites (heterotopic pregnancies) are a rare condition thought to occur in 1 of 30,000 spontaneous pregnancies. Individual cases may occur after in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT). In the past 4 1/2 years, our unit has performed 6,204 IVF/GIFT or pronuclear stage transfer cycles of treatment. Ten such pregnancies proven by surgical, ultrasound, and histological diagnosis have occurred. In the same period 640 IVF, 355 GIFT, and 6 pronuclear stage transfer clinical pregnancies were achieved. This suggests that the incidence of heterotopic pregnancy after assisted reproduction is closer to 1 of 100 pregnancies. Clinicians managing early complications of IVF, GIFT, and/or pronuclear stage transfer pregnancies should be aware of this relatively high incidence of concomitant intrauterine and extrauterine pregnancy. 相似文献
102.
Embryonic stem (ES) cells-wild-type, heterozygous, or null for alpha5-integrin-were injected ectopically into syngeneic mice to develop teratocarcinomas. alpha5-null-derived teratocarcinomas were significantly smaller than the wild-type or alpha5 heterozygous tumors. Histological analysis revealed the presence of tissues derived from all three germ layers, in all tumors. However, alpha5-null teratocarcinomas displayed less undifferentiated tissue than did the controls. Decreased proliferation and increased apoptosis were observed in the undifferentiated areas of the alpha5-null teratocarcinomas. The expression of extracellular matrix proteins, fibronectin and tenascin-C, and the basement membrane components, laminin, entactin/nidogen, and collagen IV, was similar in the different tumors, although the deposition of these molecules was more disorganized in alpha5-null teratocarcinomas. The absence of alpha5-integrin in the various tissues of the alpha5-null tumors was confirmed by immunohistochemistry. Many vessels, but not all, stained positively for alpha5-integrin, showing that they were host derived. Analysis of the area occupied by vessels revealed, on average, an 8-fold decrease in alpha5-null teratocarcinomas compared with control tumors. Staining for smooth muscle alpha-actin showed that pericytes and smooth muscle cells were recruited around the vessels in all tumors, suggesting similar vessel differentiation. Deposition of EIIIA and EIIIB and fibronectin around the vessels was observed in all tumors. The fact that some, although few, alpha5-integrin-negative vessels existed in alpha5-null tumors indicated that alpha5-/- ES cells could differentiate into endothelial cells. Endothelial cell differentiation and vessel formation were analyzed also in vitro. alpha5-null ES cells were differentiated into embryoid bodies, although they were delayed in growth and attachment. Differentiation into endothelial cells was achieved, but the organization into a complex vasculature was delayed compared with controls. We conclude that alpha5beta1-integrin plays a significant role in vessel formation both in ES cell cultures and in teratocarcinomas. Reduced vascularization likely contributed to the reduced proliferation and increased apoptosis observed in alpha5-null teratocarcinomas. 相似文献
103.
Differentiation of Helicobacter pylori isolates based on lectin binding of cell extracts in an agglutination assay.
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Plant and animal lectins with various carbohydrate specificities were used to type 35 Irish clinical isolates of Helicobacter pylori and the type strain NCTC 11637 in a microtiter plate assay. Initially, a panel of eight lectins with the indicated primary specificities were used: Anguilla anguilla (AAA), Lotus tetragonolobus (Lotus A), and Ulex europaeus I (UEA I), specific for alpha-L-fucose; Solanum tuberosum (STA) and Triticum vulgaris (WGA), specific for beta-N-acetylglucosamine; Glycine max (SBA), specific for beta-N-acetylgalactosamine; Erythrina cristagali (ECA), specific for beta-galactose and beta-N-acetylgalactosamine; and Lens culinaris (LCA), specific for alpha-mannose and alpha-glucose. Three of the lectins (SBA, STA, and LCA) were not useful in aiding in strain discrimination. An optimized panel of five lectins (AAA, ECA, Lotus A, UEA I, and WGA) grouped all 36 strains tested into eight lectin reaction patterns. For optimal typing, pretreatment by washing bacteria with a low-pH buffer to allow protein release, followed by proteolytic degradation to eliminate autoagglutination, was used. Lectin types of treated samples were stable and reproducible. No strain proved to be untypeable by this system. Electrophoretic and immunoblotting analyses of lipopolysaccharides (LPSs) indicated that the lectins interact primarily, but not solely, with the O side chain of H. pylori LPS. 相似文献
104.
Aimée E van Dijk Manon van Eijsden Karien Stronks Reinoud JBJ Gemke Tanja GM Vrijkotte 《BMC public health》2010,10(1):251
Background
Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five. 相似文献105.
A Southwest Oncology Group study on the use of a human tumor cloning assay for predicting response in patients with ovarian cancer 总被引:5,自引:0,他引:5
D D Von Hoff R Kronmal S E Salmon J Turner J B Green J S Bonorris E L Moorhead H E Hynes R E Pugh R J Belt 《Cancer》1991,67(1):20-27
A total of 211 patients with epithelial ovarian cancer (168 with tumors refractory to prior chemotherapy and 43 with no prior chemotherapy) from 33 different Southwest Oncology Group institutions had their tumors sampled and specimens shipped to two central laboratories for drug-sensitivity testing in a human tumor cloning assay. The 168 patients with a prior history of chemotherapy failure (median of four prior chemotherapeutic agents) were treated with the most effective agent(s) found in the cloning assay (23 patients), and those patients whose tumors did not form colonies in vitro or did not manifest any sensitivity to agent(s) were treated with a clinician's choice of agent(s) (101 patients). The remaining 44 of the 168 patients were not treated with chemotherapy because of deteriorating performance status or early death. The complete and partial response rate in patients treated according to assay results was 28% versus 11% for the patients treated according to clinician's choice (P = 0.03). There was no statistically significant difference in survival between the two options (6.25 versus 7 months, respectively). The 43 patients with no history of prior chemotherapy were all treated with standard combination chemotherapy, and their clinical response was compared with their in vitro sensitivity to the same agents. Overall there was a 100% true-positive rate and 100% true-negative rate for the seven evaluable patients. From these data the authors conclude that use of the human tumor cloning assay may increase the response rate but not the survival for selected patients with advanced chemotherapy-refractory ovarian cancer. The study is weakened, however, by the many steps of patient selection necessitated by inadequate tumor colony formation in vitro and the inability to treat all patients (because of early death or a rapid decline in performance status). The assay does appear to be worthy of additional study for predicting response to combination chemotherapy in patients without a prior history of chemotherapy. Finally the use of central chemosensitivity testing laboratories is feasible for testing in vitro predictive assays in a cooperative group setting. 相似文献
106.
107.
Front D; Ioselevsky G; Frenkel A; Even-Sapir E; Israel O; Kolodny GM; Feinsud M 《Radiology》1987,164(1):93-96
A single photon emission computed tomographic method was designed for the measurement of radiopharmaceutical uptake in brain tumors. Results of phantom studies showed a correlation coefficient of .99 when measured volume was compared with actual volume. The correlation coefficient for measured radioactivity concentration compared with the actual concentration was .97. In 13 meningiomas the correlation between in vivo SPECT measurements of uptake and in vitro measurements in samples of the same tumors removed surgically was .84; when two tumors that contained regions of necrosis and fibrosis were excluded it was .93. This method can be used for in vivo quantitative assessment of pharmacokinetics of labeled drug uptake in human brain tumors. 相似文献
108.
109.
110.
Canthaxanthin induces apoptosis in human cancer cell lines 总被引:3,自引:1,他引:2
Palozza P; Maggiano N; Calviello G; Lanza P; Piccioni E; Ranelletti FO; Bartoli GM 《Carcinogenesis》1998,19(2):373-376
To investigate the possibility that canthaxanthin inhibits cancer cell
growth by inducing apoptosis, human WiDr colon adenocarcinoma and SK- MEL-2
melanoma cells were treated with two different doses of the carotenoid for
48 h. Canthaxanthin was incorporated and/or associated to cells. The
treatment with the carotenoid caused growth inhibition in both cell types.
Concomitantly, apoptosis was induced. Increasing time of exposure and
carotenoid concentration, this effect was more pronounced. At 48 h, the
percentages of apoptotic cells were 13 and 15, using 1 microM
canthaxanthin, and 18 and 20, using 10 microM canthaxanthin in WiDr and
SK-MEL-2 cells, respectively. This study represents the first demonstration
that canthaxanthin is able to induce apoptosis in tumour cells.
相似文献