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991.
Gene transfer into hepatocytes mediated by herpes simplex virus-Epstein-Barr virus hybrid amplicons 总被引:1,自引:0,他引:1
Gene transfer into hepatocytes is highly desirable for the long-term goal of replacing deficient proteins and correcting metabolic disorders. Vectors based on herpes simplex virus type-1 (HSV-1) have been demonstrated to mediate efficient gene transfer into hepatocytes both in vitro and in vivo. Large transgene capacity and extrachromosomal persistence make HSV-1/EBV hybrid amplicon vectors an attractive candidate for hepatic gene replacement therapy. To assess liver-directed gene transfer, we constructed (i) a conventional HSV-1 amplicon vector encoding a secreted reporter protein (secreted alkaline phosphatase, SEAP) under the control of the HSV-1 immediate-early 4/5 promoter; (ii) a HSV-1 amplicon encoding SEAP under the control of the artificial CAG promoter (the chicken beta-actin promoter and cytomegalovirus (CMV) immediate-early enhancer); and (iii) a HSV-1/EBV hybrid amplicon, also encoding SEAP under the control of the CAG promoter. While all three vector constructs yielded high SEAP concentrations in vitro and in vivo, use of HSV-1/EBV hybrid amplicon vectors significantly prolonged the duration of gene expression. Using conventional amplicon vectors in cultured hepatocytes, SEAP was detected for two weeks, whereas SEAP was detected for at least six weeks when HSV-1/EBV amplicons were used. Intraparenchymal injection into the liver of SICD mice yielded high (up to 77 ng of SEAP per milliliter serum) and sustained (greater than three weeks) expression of SEAP. Serum transaminases (ALT/AST) were measured at different time points to monitor for hepatocellular damage. While initially elevated four times above baseline, the transaminase levels returned to normal after three to seven days. These results demonstrate the usefulness of HSV-1-based amplicons and SEAP for the evaluation of gene replacement strategies in the liver. 相似文献
992.
993.
Liisa Väkevä Eleanor Mackie Tuomo Kantomaa Irma Thesleff 《Anatomical record (Hoboken, N.J. : 2007)》1990,228(1):69-76
Tenascin is a glycoprotein of the extracellular matrix, which has been associated with differentiation of hard tissue forming cells. Alkaline phosphatase (AP) is involved in calcification, and it has also been suggested to function in cell differentiation. We have compared the distributions of tenascin and AP in the developing skull and teeth of embryonic and growing rats and mice. Tenascin was localized by immuno-Peroxidase and AP by enzyme histochemical staining of tissue sections. Both tenascin and AP were largely restricted to bone, cartilage, and teeth. In cartilage, tenascin was expressed in the perichondrium, whereas AP activity was detected only in the hypertrophic cartilage. In growing intramembranous bone, tenascin and AP were expressed in the periosteum and endosteum. AP activity was restricted to the inner layer of the periosteum, whereas tenascin expression extended to the more superficial layers. In bud-staged teeth tenascin but no AP activity was localized in the condensing mesenchymal cells around the epithelial bud. At the bell stage both tenascin and AP activity were localized in the cuspal mesenchyme, and the intensity of staining decreased towards the cervical region. In summary, tenascin was present at all sites of AP activity except in the epithelial cells of the enamel organ and the hypertrophic cartilage of the mandibular condyle. In mesenchymal tissues tenascin was more widely distributed than AP. It can be suggested that tenascin has functions at earlier stages of hard tissue formation than AP. 相似文献
994.
PhD Paul J.M. Roholl PhD MD Hans R.J. Elbers Irma Prinsen Johnny A.J. Claessens PhD MD Jan A.M. van Unnik 《Human pathology》1990,21(12):1269-1274
The actin immunophenotype of eight benign mesenchymal tumors, 14 nonsarcomatoid tumors, and 46 sarcomatoid tumors was studied, using monoclonal antibodies (MoAb) specific for alpha-smooth muscle actin (clone 1A4), alpha- and gamma-smooth muscle actin (designated CGA7), and muscle actin (designated HHF35) on frozen sections. Tumor cells of nonsarcomatoid tissues were not reactive, but all leiomyomas and five of the seven leiomyosarcomas reacted with the three MoAbs. One leiomyosarcoma was immunoreactive for the MoAb 1A4 only. One of the six malignant schwannomas showed staining for muscle actin (HHF35). The 22 malignant fibrous histocytomas (MFH) expressed these actin isoforms in various degrees. One case immunoreacted with all three MoAbs, three reacted with 1A4 only, seven reacted with CGA7 and HHF35, and two reacted with HHF35 only. Nine MFHs were not immunoreactive for any of the MoAbs specific for (smooth) muscle and actin. In addition, the expression of desmin and collagen type IV was investigated for the group of leiomyosarcomas and MFHs. Desmin was found in five leiomyosarcomas and in two MFHs. Collagen type IV was seen in all leiomyosarcomas, and was seen weakly in a few small areas in four MFHs. When we take into account the expression of all markers tested [( smooth] muscle actin, desmin, and collagen type IV), then six of the 22 MFHs were unreactive for all these markers. Five of these six tumors were located intramuscularly, whereas only half of the total number of MFH cases had an intramuscular location. The fact that 15 of 22 MFHs displayed one or more markers linked with (smooth) muscle differentiation suggests that some of the MFHs may be classified as poorly differentiated leiomyosarcomas, and that MFH is not a unique entity. 相似文献
995.
996.
Irma Slavutsky Mabel Labal de Vinuesa Juan Dupont Nora Mondini Sonia Brieux de Salum 《Cancer Genetics and Cytogenetics》1981,3(4):341-346
Two cases of lymphocytic lymphoma with a duplication of part of the long arm of chromosome #1, between bands 1q25 and 1q32, are presented. The coincidence between this finding with others in the literature supports the concept that this specific chromosome segment is related to the proliferative advantage of malignant cells in neoplasia. 相似文献
997.
Liisa Myllykangas Tuomo Polvikoski Karoliina Reunanen Fabienne Wavrant‐De Vrieze Clare Ellis Dena Hernandez Raimo Sulkava Kimmo Kontula Auli Verkkoniemi Irma‐Leena Notkola John Hardy Jordi Perez‐Tur Matti J. Haltia Pentti J. Tienari 《American journal of medical genetics. Part A》2002,114(3):288-291
ApoE ?4 allele increases the risk of late‐onset Alzheimer disease (AD) as well as the amount of beta‐amyloid deposition in the brain. Because half of AD patients do not have ApoE ?4, it is important to search for other determinants of ApoE that modify AD risk. We tested whether the haplotype background of the most common ApoE allele, ?3, influences brain amyloid deposition or the risk of neuropathologically verified AD in a population‐based sample of elderly Finns. To exclude the effects of ApoE protein polymorphism we focused these analyses on subjects homozygous for ?3. Haplotypes were defined using polymorphisms at positions ? 491 and ? 219 of the ApoE promoter and at position +113 of intron‐1. We found that ?3‐haplotypes containing the promoter allele ? 219T were associated with reduced amyloid deposition and reduced risk of neuropathologically verified AD as compared to ?3‐haplotypes containing ? 219G. The functional polymorphism(s) responsible for the haplotypic difference remains to be identified. These results indicate that there is significant allelic variation in the ApoE gene region, which modulates brain amyloid deposition and AD risk, independent of the ApoE protein polymorphism. © 2002 Wiley‐Liss, Inc. 相似文献
998.
Huijbrechts IP Erdman RA Duivenvoorden HJ Deckers JW Leenders IC Pop GA Passchier J 《International journal of behavioral medicine》1997,4(1):76-91
The relation between modification of physical activity, a risk factor for coronary heart disease, and personality characteristics was assessed in 166 survivors of a first myocardial infarction (MI). Physical activity was assessed before MI in retrospect and again 5 months after MI. Patients were divided into 3 categories according to their current daily-life physical activities: less active than before MI (n=24), equally active as before MI (n=82), or more active than before MI (n=60). A significant differentiation was found between patients who became less physically active than before MI and the other 2 categories. This less active category was characterized by feelings of disability, a low level of vigor, and feelings of anxiety. In addition, this patient group was on average older and more often female. The results were adjusted for participation in a cardiac rehabilitation program. Finally, the discussion recommends involving psychological intervention in the exercise program for the less active category of patients to diminish feelings of anxiety and disability and to improve vigor. 相似文献
999.
The vaccine candidate Vibrio cholerae 638 is protective against cholera in healthy volunteers
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García L Jidy MD García H Rodríguez BL Fernández R Año G Cedré B Valmaseda T Suzarte E Ramírez M Pino Y Campos J Menéndez J Valera R González D González I Pérez O Serrano T Lastre M Miralles F Del Campo J Maestre JL Pérez JL Talavera A Pérez A Marrero K Ledón T Fando R 《Infection and immunity》2005,73(5):3018-3024
Vibrio cholerae 638 is a living candidate cholera vaccine strain attenuated by deletion of the CTXPhi prophage from C7258 (O1, El Tor Ogawa) and by insertion of the Clostridium thermocellum endoglucanase A gene into the hemagglutinin/protease coding sequence. This vaccine candidate was previously found to be well tolerated and immunogenic in volunteers. This article reports a randomized, double-blind, placebo-controlled trial conducted to test short-term protection conferred by 638 against subsequent V. cholerae infection and disease in volunteers in Cuba. A total of 45 subjects were enrolled and assigned to receive vaccine or placebo. The vaccine contained 10(9) CFU of freshly harvested 638 buffered with 1.3% NaHCO(3), while the placebo was buffer alone. After vaccine but not after placebo intake, 96% of volunteers had at least a fourfold increase in vibriocidal antibody titers, and 50% showed a doubling of at least the lipopolysaccharide-specific immunoglobulin A titers in serum. At 1 month after vaccination, five volunteers from the vaccine group and five from the placebo group underwent an exploratory challenge study with 10(9) CFU of DeltaCTXPhi attenuated mutant strain V. cholerae 81. Only two volunteers from the vaccine group shed strain 81 in their feces, but none of them experienced diarrhea; in the placebo group, all volunteers excreted the challenge strain, and three had reactogenic diarrhea. An additional 12 vaccinees and 9 placebo recipients underwent challenge with 7 x 10(5) CFU of virulent strain V. cholerae 3008 freshly harvested from a brain heart infusion agar plate and buffered with 1.3% NaHCO(3). Three volunteers (25%) from the vaccine group and all from the placebo group shed the challenge agent in their feces. None of the 12 vaccinees but 7 volunteers from the placebo group had diarrhea, and 2 of the latter exhibited severe cholera (>5,000 g of diarrheal stool). These results indicate that at 1 month after ingestion of a single oral dose (10(9) CFU) of strain 638, volunteers remained protected against cholera infection and disease provoked by the wild-type challenge agent V. cholerae 3008. We recommend that additional vaccine lots of 638 be prepared under good manufacturing practices for further evaluation. 相似文献