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The data to be discussed in this paper are drawn from a study of three groups of infants: small (low birth weight less than 10 centile for gestational age), preterm (gestational age less than 37 weeks) and full term. The total population of this study consisted of 12 children (4 subjects for each group). The purpose of the study was to examine phonetic and lexical development in these three populations to determine both normal and delayed patterns of this development over the second year of life. The time sampled for early behaviors were 18, 19, 20, and 21 months, based on chronological age. The spontaneous verbal productions of the subjects were tape-recorded and transcribed using phonetic symbols (IPA). Comparison were made between preterm and full term infants based on both chronological and gestational age. The data resulting from the comparison of our subjects on these parameters provide us with evidence that there can be early indicators of later speech and lexical development of the group of preterm infants.  相似文献   
3.
ABSTRACT: A Male rabbit was immunized with rat testicular cytochrome (Cyt) ct and mated with normal, unimmunized females. The matings resulted in abnormal pregnancies: no offspring or stillborn or undersized liveborn offspring weighing 25–30 gm each. Another unusual observation was that fur-pulling behavior, normally exhibited by pregnant female rabbits at the end of the gestational period, was absent in all of these pregnancies. Therefore, immunization of a normal rabbit with testicular cyt ct appeared to interfere with physiological and behavioral aspects of pregnancy in normal female rabbits. The immunological basis of these findings remains to be determined.  相似文献   
4.
Interleukin-2 receptors are released in the circulation in response to antigenic or mytogenic stimulation of T-lymphocytes. Abnormal serum interleukin-2 receptor levels have been found in young children with type 1 diabetes and prediabetes. We measured interleukin-2 receptor levels in 17 patients with newly diagnosed type 1 diabetes, 21 patients with long-standing type 1 diabetes, 19 patients with long-standing type 2 diabetes, 19 islet-cell antibody positive nondiabetic polyendocrine patients, 12 islet-cell antibody-positive first-degree relatives of patients with type 1 diabetes and compared the results to age- and sex-matched normal controls. We found significantly lower interleukin-2 receptor levels in patients with newly diagnosed and long-standing type 1 diabetes compared to normal controls (87 ± 11 and 93 ± 11 vs. 142 ± 25 and 132 ± 40 U/ml, P < 0.001 and P < 0.01). There were no significant differences in interleukin-2 receptor levels between prediabetic groups and normal controls or patients with long-standing type 1 or type 2 diabetes. There was no correlation between glycosylated hemoglobin, blood glucose levels, and interleukin-2 receptor in the groups with long-standing type 1 or type 2 diabetes. We conclude that patients with type 1 diabetes have low interleukin-2 receptor serum levels. This phenomenon is acquired close to disease onset and is unlikely to be an early markers of type 1 diabetes.Abbreviations JDf Juvenile Diabetes foundation - ICA+ islet-cell antibody positive - IDDM insulin-dependent diabetes mellitus - IL-2R® interleukin-2 receptors - NIDDM non-insulin-dependent diabetes mellitus Correspondence to: R. Wagner  相似文献   
5.
T-cell homeostasis is regulated by several molecules; among these, interleukin (IL)-7 plays an essential role in the survival and homeostatic proliferation of peripheral naive T cells. In a previous study, we investigated whether human mesenchymal stromal cells (MSCs) could be engineered with the IL-7 gene to produce functional level of this cytokine. In the present study, we analyzed the impact of different quantities of IL-7 produced by MSCs on the survival and proliferation of a negative immunoselected naive (CD3(+)/CD45RA(+)) T-cell population. Co-cultivation of peripheral naive T cells with MSCs producing low (16 pg/mL) or high (1000 pg/mL) IL-7 levels or in the presence of exogenous IL-7 (0.01 ng/mL and 100 ng/mL) maintained the CD3(+)/CD45RA(+) naive T-cell phenotype. Chemokine receptor CCR7(+) expression was also maintained among this T-cell population. Naive T-cell molecular characteristics were maintained as assessed by the Vbeta spectratyping complexity score, which showed the maintenance of a broad T-cell repertoire. No Th1 or Th2 differentiation was observed, as assessed by interferon-gamma or IL-4 accumulation. In contrast, only MSCs producing high amounts of IL-7 caused increased activation (CD25 31.2% +/- 12% vs 10% +/- 3.5%; P < .05), proliferation (CD71 17.8+/-7% vs 9.3%+/-3, P < .05), apoptosis (assessed by annexin V: 18.6% +/- 5% vs 14.9% +/- 2.6%; P > .05), and the phase S cell cycle (15% vs 6.9%, P > .05). Exogenous IL-7 exhibited no significant effect. In conclusion, we demonstrated that IL-7 produced by MSCs has a dose-independent effect on naive T-cell survival while exerting a dose-dependent effect on activation/proliferation. Due to the continuous production of IL-7 by engineered cells, our system is more efficacious than exogenous IL-7.  相似文献   
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7.
We determined the distribution of DR4 subtypes in 309 DQB1*0302-positive haplotypes found in insulin-dependent diabetes mellitus (IDDM) patients and 70 control haplotypes present only in healthy family members. An increased frequency of DRB1*0401 allele (74.4% vs. 55.7%, P = 0.003) and a decrease of DRB1*0404 allele (23.6% vs. 40.0%, P = 0.0064) was revealed. A further analysis of extended haplotypes demonstrated strong linkages between various B alleles and DRB1*04 subtypes. HLA-B39 was more frequent in DRB1*0404–DQB1*0302-positive IDDM haplotypes compared with control ones (37.0% vs. 14.3%, P = 0.049), suggesting an involvement of the region telomeric to HLA-DRB1 in the susceptibility to IDDM.  相似文献   
8.
Autoimmunity may be associated with acute or chronic inflammation. In order to determine whether the inflammatory marker C-reactive protein (CRP) was an indicator of inflammatory events that precede, predict, or associate with islet autoimmunity or type 1 diabetes, CRP was measured in sequential antibody-negative, seroconversion, and follow-up-positive samples from 65 prospectively studied islet autoantibody-positive children. Although changes in CRP concentrations were observed in some children, overall CRP concentrations were similar in antibody-negative samples (median, 0.21 mg/L), antibody-positive samples (median, 0.26 mg/L), and samples at seroconversion (median, 0.26 mg/L). CRP concentrations at diabetes onset (median, 0.59 mg/L) were not significantly increased over antibody-negative samples (P = 0.07). CRP concentrations did not predict diabetes development. CRP concentrations were related to age (r = 0.26; P < 0.001) and were increased in samples obtained from October to January (P < 0.001). These findings suggest that CRP concentrations are not a valuable marker of progression to type 1 diabetes and highlight the importance of correcting analyses for seasonal variations.  相似文献   
9.
It has been suggested that maternal environment, in particular maternal autoantibodies, modify the risk of developing autoimmune diabetes in offspring. The aim of this study was to determine whether modification of maternal environment and maternal diabetes risk through immunization affects autoimmune diabetes risk in the progeny. The risk of developing insulin antibodies and of developing diabetes was determined in 113 female progeny of non obese diabetic (NOD) dams that were immunized with insulin, control antigen or vehicle before or during pregnancy. Although NOD dams immunized with insulin were rendered diabetes resistant (40% diabetes by age 36 weeks versus 100% in control dams), diabetes development in their female offspring (72%, 26/36) was similar to that in female offspring of dams immunized with glucagon (82%, 22/27) or vehicle (76%, 19/25). Furthermore, no significant differences in diabetes development or insulin autoantibody titres were observed between female progeny of insulin autoantibody positive NOD dams (82% diabetes by age 36 weeks, 18/22), insulin autoantibody negative NOD dams (75%, 41/55), and NOD dams that had antibodies against exogneous insulin (71%, 22/31). The findings suggest that modification of the maternal risk for autoimmune diabetes via antigen-specific immunization is not transferred to progeny and that fetal exposure to insulin autoantibodies does not increase the risk for diabetes development.  相似文献   
10.
Human, canine and ovine echinococcosis prevalence was determined in a highland community located in the central Peruvian Andes during 1997 and 1998. Human echinococcosis was determined using portable ultrasonography, chest X-ray examination, and an enzyme-linked immunoelectrotransfer blot (EITB) assay. Canine echinococcosis was determined using microscopy stool examinations and a coproantigen detection enzyme-immunoassay (EIA) for Echinococcus granulosus. Ovine echinococcosis was determined by an EITB assay for sheep echinococcosis and necropsy examination of viscera from domestic slaughtered animals. An abdominal ultrasound, a chest X-ray examination and an EITB for echinococcosis were performed on 214 subjects (45% of the village population). The frequency of presumptive liver/abdominal, lung and liver-lung hydatid cysts was 5.1% (11/214), 3.7% (8/214) and 0.5% (1/214), respectively. The overall prevalence of human cystic echinococcosis was 9.3% (20/214). The frequency of canine echinococcosis was 46% (23/50) and 32% (16/50) by the coproantigen EIA test and arecoline purging, respectively. The frequency of sheep echinococcosis was 65% (22/34) by the EITB and 38% (13/34) by necropsy. We demonstrated a high prevalence of human and animal echinococcosis in this Peruvian village. In remote areas where echinococcosis is endemic, both the coproantigen EIA and arecoline purging may be used for the study of canine echinococcosis; the EITB is useful in establishing the diagnosis of echinococcosis in sheep prior to necropsy.  相似文献   
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