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991.
In an attempt to track the proliferation/demise of trophoblastic tissues in women following gamete transfer (GT) or in vitro fertilization/embryo transfer (IVF/ET), we have measured levels of human chorionic gonadotropin (hCG) in serum of 180 patients on days 7 and 14 following oocyte pickup (OPU). Serum hCG levels were measured by immunoassay and by a bioassay based on the capacity of the sample to stimulate testosterone secretion by cultured mouse Leydig cells. Based on determinations of bioactive and immunoactive hCG in serum from 18 of 180 patients who subsequently delivered (12 of 73 GT, 6 of 107 IVF/ET;P<0.05) and classification of patients in accord with their compliance or noncompliance with these ranges of values, about 70% of all patients in the present study were classified as pregnant 7 days following OPU. Based on these same criteria, about 23% were pregnant 7 days later. Biochemical pregnancy rates on days 7 and 14 following GT (near 73 and 27%, respectively) were not different from the respective values following IVF/ET (near 68 and 20%, respectively:P>0.05). The luteotropin bioassay described is highly sensitive to hCG (to 0.02 mIU/ml serum) and appears appropriate to the characterization of proliferation/demise of embryonic tissues during the 14 days after gamete/embryo transfer. In addition, through its representation of the cumulative luteotropic properties of human serum and its insensitivity to biologically inactive hCG subunits; this bioassay appears more appropriate than hCG immunoassay in the monitoring of early embryonic signalling following assisted (or spontaneous) conception in the woman.  相似文献   
992.
淀粉铁、蔗糖铁对铁缺乏大鼠的补铁效应   总被引:2,自引:0,他引:2  
淀粉铁和蔗糖铁是糖和铁的络合物,本实验以相当于5~6mgFe/kg bw/d的淀粉铁或蔗糖铁连续灌胃大鼠24天。并以硫酸亚铁和普通饲料为对照,实验结果表明,淀粉铁组,蔗糖铁组,硫酸亚铁组和普通饲科组的血清铁含量(SIμg/dl)分别为111.08±22.3、118.64±26.80、136.80±54.36、83.44±22.60;血清铁蛋白含量(SFng/ml)分别为12.69±3.19、14.52±1.98、16.91±2.02、7.51±2.09;血红蛋白含量(Hbg/dl)分别为10.71±0.61、10.96±0.45、11.01±0.84、8.46±1.27,淀粉铁、蔗糖铁可被大鼠机体吸收并利用。  相似文献   
993.
We reported previously that serum prepared by delayed centrifugation of whole blood (DC serum), which is used widely in human in vitro fertilization and embryo transfer programs, has a detrimental effect on embryonic development. In an attempt to understand the mode of production of embryo-toxic factors in DC serum, we developed a model in which blood coagulation is initially blocked and later induced. The serum prepared in this fashion from whole blood (WB serum) is detrimental to mouse embryo development, as is DC serum. The toxicity of WB serum appears to derive mainly from the platelet release reaction during blood coagulation. Adenosine diphosphate and/or its degradation products may act directly to impair embryonic development and appear to be the main embryo-toxic substance(s) resulting from the platelet release reaction.  相似文献   
994.
We have defined the nature of genetic control of humoral immunity to sperm cell surface (TSDA) and acrosome (Ac) antigens. A sperm immunization dose that distinguishes between high-responder (BALB/c) and low-responder (B10) strains of mice was identified. B10 mice were unresponsive, whereas BALB/c and F1 hybrid mice responded to sperm of both parental strains. The ratio of nonresponder to responder mice in the B10 × F1 backcross and F1 × F1 inbred generations indicates anti-TSDA or anti-Ac antibody responsiveness is controlled through more than a single gene. The significant correlation found between the anti-TSDA and anti-Ac responses is consistent with the possibility that one or more genes controls antibody responsiveness against determinants common to both the Ac and sperm cell surface. Neither anti-TSDA nor anti-Ac antibody responses were linked to the I-A subregion of the responder H-2d MHC haplotype. In addition to a genetic difference in the control of humoral immunity to sperm, a difference in sperm immunogenicity among strains was observed. Antigens of the Ac of B10 sperm are more immunogenic than those of BALB/c sperm, and this trait is linked to the B10 Y chromosome.  相似文献   
995.
Summary In order to establish an experimental model for the study of immunological reactions to exogenic immunogens in the upper and lower respiratory system NMRI mice were subjected to inhalation of the mitogenic and inflammatory response inducing lectin concanavalin A (Con A) and bovine serum albumin (BSA). Immunological reactions were induced in the upper respiratory tract and in the lungs. Serologically, the course of the antibody titre was measured by radio-immunoassay over several weeks. Germinal centre reactions in the nose and paranasal sinus equivalents were the morphological correlate. The lungs showed an increase in the number of macrophages and a thickening of the alveolocapillary membrane, but no germinal centre reactions were observed. These morphological and serological results may indicate a priming of the immune response in the upper respiratory tract leading to a subsequent production of antibodies in the lung.  相似文献   
996.
The effects of breast and bottle-feeding on serum immunoglobulin levels and specific antibody responses have been examined in 30 infants on five occasions from 6 days until 9 months of age. No significant differences were found on any sample occasion between the two feeding groups in total immunoglobulin levels of G, M and A classes or in class-specific antibody responses to tetanus toxoid vaccine. This suggests that the capacity of the two groups to make serum antibodies develops similarly. Concentrations of antibodies to commensal Escherichia coli 'O'lipopolysaccharide antigens, however, were significantly greater in the bottle-fed group, and it is suggested that this difference is due to an increase in the exposure of the systemic immune system to these gut antigens in the bottle-fed infants. There are several possible explanations for this increased exposure and the resulting effects on the infants'immune system. These experiments also illustrate a possible role of breast milk in stimulating the immune system.  相似文献   
997.
ABSTRACT. Serum concentrations of iron, copper, zinc and magnesium were determined in 27 Swedish children with well controlled diabetes without longterm diabetic complications. Thirteen of the diabetic children had age- and sex-matched healthy controls. Significantly lower serum magnesium concentrations were found in the diabetic children than in the matched healthy controls ( p <0.01). The levels of iron, copper and zinc did not differ in the diabetic children from those in the controls. A negative correlation between serum magnesium level and duration of diabetes was found ( p <0.05). This is seemingly the first report of hypomagnesemia in diabetic children.  相似文献   
998.
The prevalence of cervical Chlamydia trachomatis infection in healthy, symptomless full-term pregnant women (n = 92) was found to be low (1.1%). Chlamydial cervical IgA antibodies, as measured by solid-phase radioimmunoassay (RIA), were found in 5.3%, but amniotic fluid chlamydial RIA IgA antibodies were almost absent. Serum IgG antibodies were measured with indirect immunofluorescence (IF). Of the mothers 9.8% had a titer greater than or equal to 1:64, correlating closely with the figure of 10.9% for infants' cord-blood IF serology. Finally, a case report is presented. A child born to a Chlamydia trachomatis positive mother developed isolation positive chlamydial pneumonia.  相似文献   
999.
This report describes the results of hematology, serum biochemistry, growth, and organ weight studies undertaken on pigs from nine cohorts of qualified pathogen free (QPF) pigs reared within a high welfare bioexclusion facility as potential organ source animals. Confirmation of the high health status of the pigs was given through total leukocyte counts and serum globulin concentrations that fell below the expected reference range for conventional pigs. The calculated mean growth rate for QPF pigs was found to exceed target rates set for optimum genotype commercial pig herds. Body weights of QPF pigs were compared with kidney, heart and liver weights at necropsy.  相似文献   
1000.
A structure-activity study of the neurokinin A (NKA) fragment NKA(4-10) was performed to investigate the importance of amino acid residues for receptor efficacy, potency and affinity at the NK(2) receptor in human colon circular muscle. Fourteen analogs of NKA(4-10) were produced with substitutions at positions 4, 5, 7, 9 and/or 10 of NKA. Their potencies were determined by in vitro contractile responses and affinities by radioligand binding using [125I]NKA. Functional potency was enhanced 8-fold by single amino acid substitutions with Lys(5) and MeLeu(9) but not significantly altered by substitutions Glu(4), Arg(5), His(5) and Nle(10). The multiply-substituted analogs [MeLeu(9),Nle(10)]NKA(4-10), [Lys(5),MeLeu(9),Nle(10)]NKA(4-10) and [Lys(5),(Tyr(7)),MeLeu(9),Nle(10)]NKA(4-10) displayed 6-9-fold increase in potency. Although [Arg(5),Nle(10)]NKA(4-10) was similar in potency to NKA(4-10), it was the only analog to show significantly reduced efficacy. All analogs were able to compete fully for [125I]NKA binding. [Lys(5),MeLeu(9)]NKA(4-10), [MeLeu(9),Nle(10)]NKA(4-10), [Lys(5),Nle(10)]NKA(4-10) and analogs containing single substitutions with Glu(4), Arg(5), Lys(5) and MeLeu(9) displayed significantly higher affinity, whereas those with Nle(10) and [Glu(4),Nle(10)] substitutions showed significantly lower affinity than NKA(4-10). There was a positive correlation (r=0.63) between binding affinity and functional potency, which was markedly improved (r=0.95) by removal of three analogs: [Lys(5),MeLeu(9),Nle(10)]NKA(4-10), [Lys(5),Tyr(7),MeLeu(9),Nle(10)]NKA(4-10) and [Lys(5),Tyr(I(2))(7),MeLeu(9),Nle(10)]NKA(4-10). These exhibited similar binding affinities to that of NKA(4-10) but were more potent in functional studies, possibly indicating a different mechanism of receptor interaction. In conclusion, substitution of Ser(5) with Lys, and/or N-methylation of Leu(9), were the most effective changes to increase functional and binding potency of NKA(4-10) at the human colon NK(2) receptor.  相似文献   
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