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451.
452.
Age-related changes in deformability of human erythrocytes 总被引:5,自引:1,他引:5
Sutera SP; Gardner RA; Boylan CW; Carroll GL; Chang KC; Marvel JS; Kilo C; Gonen B; Williamson JR 《Blood》1985,65(2):275-282
The present study was designed to further the characterization of age- related changes in the deformability of human erythrocytes. The top (approximately young) and bottom (approximately old) 10% fractions of density-separated red cells from ten normal donors were subjected to graded levels of shear stress in a rheoscope. Measurements were made of steady-state elongation (cells tank treading in a state of dynamic equilibrium) and the time course of shape recovery following abrupt cessation of shear. In parallel with the rheologic experiments, several physical and chemical properties were assayed to determine correlates of mechanical properties. These included mean cell volume, mean corpuscular hemoglobin concentration, type A1 hemoglobin, glucosylation of membrane proteins, and membrane phospholipid and protein concentration. The microrheologic observations revealed that only about 90% of the old cells retained their capacity to tank tread. However, the tank-treading cells elongated less than their younger counterparts at corresponding levels of shear stress, thus demonstrating a reduced level of deformability. Further analysis of the data indicates that increases in membrane viscosity and elastic modulus along with a significant loss in excess surface area contribute to the limitation of the ability of the older cells to change shape. 相似文献
453.
MK GUPTA RN MISRA N CHAWLA H MANI CN CHOWDHRY SP SINGH S GUPTA 《Medical Journal Armed Forces India》2001,57(3):188-190
75 patients with clinical features suggestive of malaria were studied to evaluate the efficacy of immunochromatographic test (ICT), which detects histidine rich protein-2 antigen secreted by Plasmodium falciparum (Pfhrp-2), as against direct microscopy. There were 40 cases of P falciparum malaria, 14 cases of P vivax malaria and 21 cases of non-malarial fevers. Direct microscopy could detect 27(67.5%) P falciparum cases but failed to detect 13 cases (32.5%) whereas ICT could detect 35(87.5%) P falciparum cases out of 40 but failed to detect 5(12.5%) cases. All the P vivax cases and non-malarial fever cases were negative for ICT. The sensitivity and specificity of ICT is 87.5% and 100% respectively where as the positive predictive value and the negative predictive value of the test is 100% and 87.5% respectively. It is concluded that ICT test is a good adjunct to blood smear studies in fever cases with neurological and multiorgan dysfunction and in antenatal ladies.Key Words: ICT, P falciparum 相似文献
454.
GH Verrips RA Hirasing M Fekkes T Vogels SP Verloove-Vanhorick HA Delemarre-Van de Waal 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(2):154-158
The aim of the study was to test the hypothesis that daily administration of growth hormone using the Medi-Jector® results in fewer adverse psychological responses than needle injection with a multidose injection pen. The Medi-Jector is a needle-free injection device that can deliver growth hormone subcutaneously through jet injection. The group studied consisted of 18 children aged 10 y or over who were participating in a study of the bioequivalence and bioequipotence of the administration of growth hormone through jet injection or needle injection. Previously, all subjects had received growth hormone therapy with commercially available multidose injection pens. The study was designed as a prospective, randomized, two-period cross-over trial. A questionnaire was used to assess psychological responses such as non-compliance, opinion on ease of preparation, affective responses to administration and local side-effects, as well as overall preference. In addition, the subjects kept a diary during the study. The subjects found the Medi-Jector less offputting (p < 0:01), less painful with respect to both frequency (p <0.04) and intensity (p < 0.01) and less unpleasant (p < 0.05) than a multidose injection pen with a 28G needle (p <0.01). No difference in compliance was detected. Most subjects preferred the Medi-Jector for future use (p < 0.05). The mean score on a 1–10 point scale (10 is excellent) was 7.9 (SD 1.4) for the Medi-Jector and 6.8 (SD2.3) for the multidose injection pen (p <0.08). The prevalence of visible bruises each day was higher (p < 0.01) with the Medi-Jector (2.5, SD 2.1) than with the multidose injection pen (0.7, SD 1.1), but children showed indifferent affective responses to bruising. Thirteen out of 18 subjects decided to continue therapy with the Medi-Jector (p < 0.06). It is concluded that use of the Medi-Jector in growth hormone therapy tends to lead to fewer adverse psychological responses than a multidose injection pen with 28G needles. 相似文献
455.
Maternally acquired immunity in newborns from women infected by the human immunodeficiency virus 总被引:2,自引:0,他引:2
MI de Moraes-Pinto CK Farhat SB Carbonare SP Curti MES Otsubo DS Lazarotti RC Campagnoli MMS Carneiro-Sampaio 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S385):1034-1038
Maternally acquired immunity was studied in 16 pairs of human immunodeficiency virus (H1V)-seropositive women and their newborns, and was compared to 18 control mother-newborn pairs. The HIV-infected women had higher IgG levels than the control subjects, but no difference was observed between newborn samples, presumably due to the limited placental IgC transfer in the HIV group. A poor type 2 poliovirus antibody transfer was also noted in this group. The population of newborns lacking demonstrable measles antibodies was higher in the HIV group than in the control group, probably because many of the HIV-infected mothers lacked measles antibodies also. These results show that maternally acquired immunity may be affected to newborns from HIV-infected women, either because of low maternal serum antibody levels or deficient transplacental transfer. If so, the measles vaccine schedule should be revised for these children and the same should be done for future passive immunization regarding fetus protection in pregnant HIV-seropositive women. 相似文献
456.
457.
458.
Two children with chronic renal failure developed aluminum intoxication as a result of long-term ingestion of aluminum hydroxide for the control of hyperphosphatemia. In each child, bone biopsy confirmed severe osteomalacia, the absence of features of hyperparathyroid bone disease, and massive aluminum deposition at the bone-osteoid junction. Radiographs during the period of aluminum intoxication demonstrated osteopenia, pathologic fractures, fraying of the metaphyses of the long bones, and widening of the physis. When aluminum hydroxide therapy was discontinued (each patient) and aluminum was removed with chelation therapy (one patient), radiographs demonstrated a distinctly unusual pattern of healing. Calcification of the long bones began at the most recently formed osteoid and then proceeded toward the diaphysis. This unusual healing pattern created lucent defects and a transient "bone within a bone" appearance, which resolved with further healing. 相似文献
459.
J Drummond G Johnson D G Nickell D F Ortwine R F Bruns B Welbaum 《Journal of medicinal chemistry》1989,32(9):2116-2128
Except for structurally similar small amino acids, such as alanine, beta-alanine, and serine, compounds acting as glycine-receptor agonists are an unknown class of pharmacological agents. To investigate the potential of small, substituted heterocycles to act as glycine agonists, we have evaluated the similarities between glycine and a series of hydroxy- and amino-substituted pyrazoles and isoxazoles through complementary molecular modeling techniques. Using a "scorecard approach" to determine the overall similarity of projected agonist structures to glycine, we prioritized synthesis and subsequently prepared several novel derivatives. The biological activity of these compounds was compared to that of glycine by using a [3H]strychnine-mediated glycine receptor binding assay. Despite the close similarity in the calculated parameters when compared to glycine, no significant receptor-binding activity was observed for the targeted analogues. These results illustrate the structurally exacting nature of the glycine receptor. 相似文献
460.
Kala azar continues to be a medical problem in India and with the increase in incidence of HIV Infection it is likely that kala azar will be encountered more frequently and in its atypical forms. To aid diagnosis, several immunological tests are now available and they are more sensitive and specific than the aldehyde test. Like many other diseases today, the treatment of kala azar is hampered by drug resistance. Newer drugs are available and so are new delivery systems. Kala azar develops frequently in the HIV infected person before development of AIDS. The presentation is atypical and leishmanial species other than L. donovani may also be the infecting agents. A combination of sandfly control, detection and treatment of patients and prevention of drug resistance continues to the ideal approach for the control of the disease.KEY WORDS: Kala azar, Leishmaniasis, HIVWHO estimates that more than 200 million people in the world are exposed to leishmanial parasites and more than 500,000 people develop clinical visceral leishmaniasis each year [1]. Major epidemics have occurred in the eastern part of our country and some other parts of the world [2]. Large scale drug failure has been the outstanding feature of the Indian epidemic of 1991, leading to increased morbidity and mortality. Certain clinical manifestations like lymphadenopathy which were not seen in Indian kala azar earlier, have been reported from Bihar and West Bengal [3]. With the increasing incidence of HIV infection, more atypical presentations are being noted [1]. Due to the development of widespread resistance to conventional drugs, several new drugs and other modalities of treatment have been developed and the conventional drugs are being tried in modified dosages with variable success. 相似文献