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21.
Sebastiano Franscella Charles-Abram Favrod-Coune Gianpaolo Pizzolato Sylvia L. Asa Rolf Gaillard Jean Berney Jacques Philippe 《Endocrine pathology》1991,2(2):111-116
The diagnosis of pituitary corticotroph adenoma relies on the demonstration of a loss of the normal feedback control of adrenocorticotropic
hormone (ACTH) biosynthesis by cortisol. The marked variability in the degree of ACTH suppression by glucocorticoids in these
tumors, however, greatly enhances the difficulty in distinguishing Cushing’s disease from other syndromes of glucocorticoid
excess. To illustrate this variability, we describe the clinical, biochemical, and morphological characteristics of a pituitary
corticotroph adenoma in a 63-year-old woman, who presented with symptoms of a sellar mass but did not initially have florid
Cushing’s disease. Light and electron microscopy of the pituitary tumor showed a corticotroph adenoma with Crooke’s hyalinization
of the tumor cells, characterized by the accumulation of keratin immunoreactive microfilaments similar to those observed in
normal corticotrophs in the presence of excess glucocorticoids. This case illustrates an unusual clinical presentation that
may be associated with pituitary corticotroph adenoma showing Crooke’s hyalinization. 相似文献
22.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
23.
24.
Jean-Philippe Gaillard Rgis Bataille Herv Brailly Caroline Zuber Kiyoshi Yasukawa Michel Attal Naoko Maruo Tetsuya Taga Tadamitsu Kishimoto Bernard Klein 《European journal of immunology》1993,23(4):820-824
Soluble human interleukin-6 receptor (sIL-6R) was measured in the serum of 30 healthy individuals, 32 individuals with monoclonal gammopathy of undetermined significance (MGUS), 20 patients with early multiple myeloma (MM) and 54 patients with overt MM. The serum activity recognized by an immunoradiometric assay was determined to be sIL-6R, because of its binding capacity to IL-6 and its molecular mass of 55 kDa. All sera of healthy individuals contained sIL-6R (mean value: 89 ng/ml, range 17-300 ng/ml). Serum sIL-6R levels were increased by 51% in patients with MGUS (mean value: 135 ng/ml, p<0.005), by 44% in patients with early myeloma (mean value: 128 ng/ml, p<0.001) and by 116 % in patients with overt MM (mean value: 193 ng/ml, p<0.001). In patients with MM, a complete lack of correlation (p>0.7) was found between serum sIL-6R levels and other previously recognized prognostic factors in this disease, particularly serum IL-6 levels and those factors related to tumor cell mass. The independence of serum sIL-6R levels on tumor cell mass was directly demonstrated by studying four patients with MM treated with autologous bone marrow transplantation for periods of between 320 and 760 days. These levels were found to be remarkably stable and constant, independent of whether patients relapsed or achieved complete remission. Finally, physiological concentrations of sIL-6R were found to increase by tenfold the sensitivity of human myeloma cell lines to IL-6. These observations suggest a high control of the sIL-6R level in vivo, and, possibly, an important functional role of this circulating protein in patients with monoclonal gammopathies. 相似文献
25.
Western blot analysis of antibody response to pneumococcal protein antigens in a murine model of pneumonia. 下载免费PDF全文
H Mouneimne M Juvin J L Beretti E Azoulay-Dupuis E Vallee P Geslin P Petitpretz P Berche J L Gaillard 《Clinical and Vaccine Immunology : CVI》1997,4(6):778-782
To detect new antigen candidates for serological tests, we studied the antibody response to pneumococcal protein antigens in mice infected intratracheally with various Streptococcus pneumoniae strains. Sera were tested by Western blotting against whole-cell protein extracts. Mice developed a detectable immunoglobulin G-type response against a small number of polypeptides. The antibody response was strain dependent: sera from individuals infected with the same strain gave similar banding patterns on immunoblots. The banding patterns varied with the strain used for infection. However, a band at 36 to 38 kDa was recognized by all reactive sera. This band appeared to correspond to a polypeptide that was antigenically well conserved among the different S. pneumoniae serotypes. An antibody response to this antigen developed in mice irrespective of the capsular type, the virulence, and the susceptibility to penicillin G of the infecting strain. Thus, this 36- to 38-kDa protein antigen may be of value for the development of a serological test for humans. 相似文献
26.
Placental inflammation and perinatal transmission of HIV-1 总被引:2,自引:0,他引:2
Mwanyumba F Gaillard P Inion I Verhofstede C Claeys P Chohan V Vansteelandt S Mandaliya K Praet M Temmerman M 《Journal of acquired immune deficiency syndromes (1999)》2002,29(3):262-269
The effect of placental membrane inflammation on mother-to-child transmission (MTCT) of HIV-1 is reported. Placentas from HIV-1-infected women were examined as part of a perinatal HIV-1 project in Mombasa, Kenya. Polymerase chain reaction analysis was used to test for HIV-1 in the infants at birth and at 6 weeks. The maternal HIV-1 seroprevalence was 13.3% (298 of 2,235). The overall rate of MTCT of HIV-1 was 25.4%; polymerase chain reaction analysis revealed that of the 201 infants 6.0% (12) were already HIV-1-positive at birth (intrauterine transmission) and 19.4% (39) were infected during the peripartum period or in early neonatal life (perinatal transmission). The prevalence of acute chorioamnionitis was 8.8%, that of deciduitis was 10.8%, and that of villitis was 1.6%. Acute chorioamnionitis was independently associated with peripartum HIV-1 transmission but not with in utero MTCT (17.9% vs. 6.7%, respectively; adjusted odds ratio, 3.9; 95% confidence interval, 1.2-12.5; p =.025). Other correlates of perinatal MTCT were presence of HIV in the genital tract and in the baby's oral cavity and a high maternal viral load in peripheral blood. The adjusted population attributable fraction of 12.8% (95% confidence interval, 1.5%-22.8%) indicated that approximately 3% of MTCT could be prevented if acute chorioamnionitis was eliminated. We suggest that further research on the role of antimicrobial treatment in the prevention of chorioamnionitis and the reduction of peripartum MTCT needs to be performed. 相似文献
27.
B. Pron J. Merckx P. Touzet A. Ferroni C. Poyart P. Berche J. L. Gaillard 《European journal of clinical microbiology & infectious diseases》1995,14(7):599-601
A case of chronic septic arthritis and osteomyelitis in a prosthetic knee joint due toClostridium difficile is reported. A knee prosthesis was installed in a 16-year-old boy for surgical treatment of an osteosarcoma of the femur. Later, the patient suffered a traumatic closed fracture of his patella, and a sterile fluid was aspirated. One month later, the joint displayed inflammation. Culture of the articular fluid yielded a nontoxigenicClostridium difficile strain. Despite several attempts using conservative medical treatment with penicillins and ornidazole,Clostridium difficile strains with the same antibiotic susceptibility pattern were repeatedly isolated from the joint over an eight-month period. The foreign material was then ablated, and finally, the patient's leg was amputated one year afterClostridium difficile was first isolated. The possible sources of contamination in our case and other reported cases of extraintestinal infection due toClostridium difficile are discussed. 相似文献
28.
As judged by the ability of their genomes to hybridize, reovirus serotypes 1 and 3 are related to the extent of about 70% to each other and about 10% to serotype 2. Two techniques were developed to measure the extent to which the individual cognate genes of these serotypes are related. Both involve comparison of heterologous hybrid genes that contain plus and minus strands of genes of different serotypes with homologous hybrid genes (molecules formed by reannealing the separated plus and minus strands of the same gene). In the first technique, the amounts in such hybrids of material sensitive to ribonuclease under standard conditions were compared; in the second, their relative electrophoretic mobilities. The results obtained with the two techniques agreed well. They showed that for the three reovirus isolates examined (the Lang strain of serotype 1, the D5 Jones strain of serotype 2, and the Dearing strain of serotype 3), all 10 genes of serotypes 1 and 3 are much more closely related to each other than to the genes of serotype 2. Although this result relates to only three isolates of mammalian reovirus, it suggests that the gene sets of reovirus serotypes 1, 2, and 3 evolved independently of each other. Apparently double infection of hosts with strains of two reovirus serotypes, which would very likely yield recombinants, occurs infrequently and/or such recombinants have a lower survival advantage than strains containing “pure” gene sets. The results also show that the gene that has diverged most markedly during evolution is the S1 gene, the gene that encodes the minor outer shell capsid protein σ1 which is the reovirus cell attachment protein and hemagglutinin and possesses the most type-specific antigenic determinants. The serotype 1 and 3 S1 genes are about 10% homologous, serotype 2 and serotype 1 or 3 S1 genes about 3%. The genes that have diverged least are the three L genes (85–90% homology for the serotype 1 and 3 L genes). In all cases, the serotype 2 and serotype 1 or 3 genes exhibit no more than 20%, and often less than 10% homology. In spite of this high degree of divergence, the antigenic determinants on proteins encoded by genes of serotype 2 on the one hand and serotypes 1 and 3 on the other hand are, with the exception of those on proteins σ1, highly conserved, and the 60 to 80 nucleotides at the 5′- and 3′-termini of at least three sets of cognate genes (L3, M3, and S2) of all three serotypes, serotype 1 and 3 as well as serotype 2, are highly homologous and in some instances almost identical. Thus, while some regions of reovirus genes have diverged greatly during evolution, others have been highly conserved. 相似文献
29.
BACKGROUND: Airway inflammation and infection are early events in cystic fibrosis (CF) pathogenesis. The existence of an imbalance in the immune cell population of the CF fetal airway before infection remains completely unknown. OBJECTIVE: The aim of this study was to determine whether early signs of inflammation are observed in CF airways during human fetal development. METHODS: Tracheas and lungs were collected from 21 CF and 16 non-CF fetuses. In tissue sections, the numbers of neutrophils, mast cells, macrophages, and B and T lymphocytes were quantitatively analyzed by means of image cytometry. The presence of IL-4, IL-6, IL-8, IL-10, RANTES, IFN-gamma, TNF-alpha, and NF kappa B and its inhibitor I kappa B-alpha was qualitatively evaluated by immunofluorescent staining. RESULTS: During fetal airway development, epithelial and glandular differentiation, as well as the distribution of inflammatory markers, was similar in CF and non-CF tissues. Significant differences between CF and non-CF fetal airways were observed only in the numbers of mast cells and macrophages. In the CF trachea, the mast cell number increased slowly but continuously, whereas in the non-CF trachea this number rapidly reached a plateau. In the CF lung, the macrophage number increased with time, whereas in the non-CF lung it decreased. CONCLUSION: Although no intrinsic inflammation was demonstrated, we observed a distinct appearance of mast cells and macrophages in CF airways in comparison with non-CF airways during fetal development. These 2 cell populations were greater in CF airways at a late stage of fetal development, suggesting their possible involvement in the early onset of inflammation in CF infants. 相似文献
30.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献