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71.
Immunoglobulin G and immunoglobulin M polar staining of Toxoplasma gondii in the indirect immunofluorescence test. 总被引:2,自引:1,他引:2 下载免费PDF全文
Polar staining (PS) of Toxoplasma gondii in the indirect immunofluorescence test has been considered a nonspecific reaction caused exclusively by certain immunoglobulin M (IgM) antibodies and confined to the anterior end of the parasite. After we observed a patient with positive serology for Chagas' disease who presented an IgG PS reaction, we studied sera from 120 patients with Chagas' disease, 20 sera from patients with Leishmania donovani infection, and 30 sera from patients with Leishmania braziliensis infection. When only those specimens having no detectable anti-Toxoplasma activity were considered, a significantly (P less than 0.01) higher prevalence of IgG PS was found in the Chagas' disease and L. donovani groups than in sera from normal American and Brazilian adults. Those sera also showed higher PS titers (1:64 to 1:1,024) when compared with controls (1:16 to 1:64). IgG PS titers did not decrease after serum treatment with 2-mercaptoethanol. However, the same treatment removed completely IgM PS. IgG PS, but not IgM PS, could be removed by adsorption with Trypanosoma cruzi epimastigotes. IgM PS was found in all samples studied, except in 41 of a group of 43 umbilical cord sera. It was found that the antigen source and the microscopy system can influence the detection of PS. It is proposed that after finding an intense IgG PS reaction, the laboratory should screen such serum also for anti-T. cruzi antibodies which may be undetected in the sample. 相似文献
72.
Paradiso A Abatangelo M Piepoli S Tommasi S Xu JM Caponio MA Marzullo F D'Auria C Achille G Grammatica L 《Cancer Genetics and Cytogenetics》2002,132(2):141-144
Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found. 相似文献
73.
Dual role of interleukin-4 (IL-4) in pulmonary paracoccidioidomycosis: endogenous IL-4 can induce protection or exacerbation of disease depending on the host genetic pattern 下载免费PDF全文
Arruda C Valente-Ferreira RC Pina A Kashino SS Fazioli RA Vaz CA Franco MF Keller AC Calich VL 《Infection and immunity》2004,72(7):3932-3940
Resistance to paracoccidioidomycosis, the most important endemic mycosis in Latin America, is thought to be primarily mediated by cellular immunity and the production of gamma interferon. To assess the role of interleukin-4 (IL-4), a Th2 cytokine, pulmonary paracoccidioidomycosis in IL-4-depleted susceptible (B10.A) and intermediate (C57BL/6) mice was studied. Two different protocols were used to neutralize endogenous IL-4 in B10.A mice: 1 mg of anti-IL-4 monoclonal antibody (MAb)/week and 8 mg 1 day before intratracheal infection with 10(6) Paracoccidioides brasiliensis yeast cells. Unexpectedly, both protocols enhanced pulmonary infection but did not alter the levels of pulmonary cytokines and specific antibodies. Since in a previous work it was verified that C57BL/6 mice genetically deficient in IL-4 were more resistant to P. brasiliensis infection, we also investigated the effect of IL-4 depletion in this mouse strain. Treatment with the MAb at 1 mg/week led to less severe pulmonary disease associated with impaired synthesis of Th2 cytokines in the lungs and liver of control C57BL/6 mice. Conversely, in IL-4-depleted C57BL/6 mice, increased levels of tumor necrosis factor alpha and IL-12 were found in the lungs and liver, respectively. In addition, higher levels of immunoglobulin G2a (IgG2a) and lower levels of IgG1 antibodies were produced by IL-4-depleted mice than by control mice. Lung pathologic findings were equivalent in IL-4-depleted and untreated B10.A mice. In IL-4-depleted C57BL/6 mice, however, smaller and well-organized granulomas replaced the more extensive lesions that developed in untreated mice. These results clearly showed that IL-4 can have a protective or a disease-promoting effect in pulmonary paracoccidioidomycosis depending on the genetic background of the host. 相似文献
74.
Evaluation of dot enzyme-linked immunosorbent assay for mucocutaneous leishmaniasis and comparison with microplate enzyme immunoassay. 下载免费PDF全文
A dot enzyme-linked immunosorbent assay (dot ELISA) was evaluated and compared with a standard microplate ELISA (immunoglobulin G [IgG] ELISA) for the serological diagnosis of mucocutaneous leishmaniasis. The two assays were used to test 113 serum specimens from the following groups: normal individuals and patients with deep mycoses, toxoplasmosis, mucocutaneous leishmaniasis, visceral leishmaniasis, Chagas' disease, malaria, and schistosomiasis. Both tests exhibited cross-reactivity when testing specimens from cases of visceral leishmaniasis and Chagas' disease. The dot ELISA proved to be economical with respect to use of reagents and was easy to perform. Interpretation could easily be made by visual inspection of reaction endpoints in the nitrocellulose disks, obviating the need for spectrophotometric readings. There were no significant differences in sensitivity between the dot ELISA and the IgG ELISA at a cutoff level either of 20 or 40. However, its most remarkable feature was the high specificity compared with that of the IgG ELISA. Because of its ease of performance and high sensitivity and specificity, the dot ELISA should be an excellent test to be executed in the field during seroepidemiological surveys. 相似文献
75.
Postnatal development of dopamine receptor expression in rat peripheral blood lymphocytes. 总被引:1,自引:0,他引:1
Daniele Tomassoni Elena Bronzetti Franco Cantalamessa Fiorenzo Mignini Alberto Ricci Maurizio Sabbatini Seyed K Tayebati Damiano Zaccheo 《Mechanisms of ageing and development》2002,123(5):491-498
Postnatal development in the expression of dopamine D1-like and D2-like receptors was investigated in peripheral blood lymphocytes of male Wistar rats aged 1, 3, 4, 8, 12 and 16 weeks of age by radioligand binding assay techniques. Sample of frontal cortex, striatum and hippocampus were also investigated as reference tissues. The dopamine D1-like receptor antagonist [3H]SCH 23390 and the dopamine D2-like receptor agonist [3H]7-OH-DPAT were used as radioligands. The affinity (K(d)) of [3H]SCH 23390 or of [3H]7-OH-DPAT binding was unchanged in lymphocytes of rats of different age groups. The density (B(max)) of [3H]SCH 23390 binding sites increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 8th week of age, and then increased slightly at 12 and 16 weeks of age. The B(max) value of [3H]7-OH-DPAT binding to lymphocytes increased from the 1st to the 3rd week of age, remained constant from the 3rd to the 4th week, increased again until the 12th week and then plateaued. Dopamine D1-like and D2-like receptor maturation in frontal cortex, hippocampus and striatum revealed an increased receptor density until the 4th week of age and a relative stabilization of receptor density values between the 4th to the 12th week depending on the area considered. Comparatively postnatal maturation of lymphocyte dopamine D1-like receptors displayed a pattern different from that of brain areas investigated, whereas maturation of D2-like receptors displayed a pattern similar to that of striatum. The quantitative and/or qualitative dissimilarities between development of lymphocyte and brain dopamine receptors suggest that from a developmental point of view lymphocyte dopamine receptors probably cannot be considered as a marker of homologous brain receptors. 相似文献
76.
This research project was undertaken as a component of a comprehensive assessment of the University of Connecticut's freshman football team. The purpose of this study was to identify weaknesses in the neck musculature and note any relationships between strength differences and cervical spine stability. Neck muscle strength was evaluated using isometric contractions for the motions of flexion, extension, and right and left lateral flexion. Statistical correlations were derived for each of the 28 male subjects, who were divided into two groups of 14 linemen and 14 runningbacks. A Human Performance Regulator, which electrically evaluates neuromuscular force produced during an isometric contraction, was used to measure the force applied. A typical weightlifting power rack was used as a stabilization platform. The data recorded indicates that there are significant differences between the neck muscle strength of the two groups, as well as differences in neck muscle strength of individuals between their right and left sides. Looking at these muscular differences and their relationship to cervical vertebrae alignment during lateral flexion, the authors contend that blocking or tackling with the head in a laterally flexed position, to supposedly hit with the shoulder, places the cervical spine in a structurally weak position lacking muscular support, and predisposes the athlete to cervical spine injuries. J Orthop Sports Phys Ther 1987;8(7):351-356. 相似文献
77.
Malignancies in the acquired immunodeficiency syndrome 总被引:1,自引:0,他引:1
Alexandra M. Levine M.D. Parkash S. Gill M.D. Franco Muggia M.D. 《Current problems in cancer》1987,11(4):209-255
Aside from opportunistic infections, several neoplasms have been identified as part of the spectrum of acquired immunodeficiency syndrome (AIDS) as defined by the Centers for Disease Control. Kaposi's sarcoma (KS) was the first such neoplasm to be recognized within the spectrum of AIDS. Although the classic form of Kaposi's sarcoma had been well recognized prior to the epidemic of AIDS, it was quite distinct from the illness that was seen in its "epidemic" form in young homosexual males. In this setting, Kaposi's sarcoma is an aggressive disease, with extensive involvement of skin and mucous membranes, early dissemination to lymph nodes, impressive development of extreme lymphedema, even in the absence of bulky adenopathy, and rapid spread to visceral organs, including lungs and gastrointestinal tract, among others. Although rapid clinical progression and short median survival have been the rule, a spectrum of disease has been seen such that some patients have survived for many years with disease limited to the skin. Certain clinical and laboratory features, such as presence of unexplained fever, night sweats, weight loss ("B" symptoms), or significant T-4-lymphocytopenia, have been identified as indicators of poor prognosis. Various therapeutic interventions have been employed in epidemic KS, and although partial and complete remissions have occurred, no regimen yet reported has significantly improved the survival of treated patients. High-dose recombinant alpha interferon has produced response rates in approximately 30% of treated patients, although toxicity has been observed in approximately 30% as well. Likewise, vinblastine has produced similar response rates with no evidence of long-term efficacy or "cure." Aside from Kaposi's sarcoma, lymphoma primary to the central nervous system was recognized early in the AIDS epidemic as a criterion for inclusion within AIDS in patients less than sixty years of age. Several years after the initial reports of disease, it became apparent that specific types of systemic lymphoma were also quite extraordinary, and the definition of AIDS was amended in June 1985 to include high-grade B-cell lymphomas in individuals who had positive serology or virology for the human immunodeficiency virus (HIV). The AIDS-related lymphomas are characteristic, both pathologically and clinically. The vast majority of these cases have been high-grade B-lymphoid tumors of either immunoblastic or small-non-cleaved type (also known as "undifferentiated," Burkitt, or Burkitt-like).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
78.
Cholinergic modulation of an acetylcholine receptor-like antigen on the surface of chick ciliary ganglion neurons in cell culture 总被引:7,自引:0,他引:7
M A Smith J F Margiotta A Franco J M Lindstrom D K Berg 《The Journal of neuroscience》1986,6(4):946-953
Chick ciliary ganglion neurons have a membrane component that shares an antigenic determinant with the "main immunogenic region" of the alpha subunits in nicotinic ACh receptors from skeletal muscle and electric organ. Ultrastructural studies on antibody binding in the ganglion have shown that the cross-reacting antigen on the neuron surface is located predominantly in synaptic membrane. Biochemical studies have shown that the cross-reacting component has a number of other properties expected for the ganglionic nicotonic ACh receptor and that it is distinct from the alpha-bungarotoxin binding component in the tissue. Here we show that ciliary ganglion neurons grown in dissociated cell culture express a similar component that cross-reacts with monoclonal antibodies to ACh receptors, and that the number of antibody-binding sites on the neurons can be modulated by exposure to cholinergic agonists and a protein neurotoxin that reversibly inhibits ACh receptors on the neurons. In most, though not all, cases, levels of ACh sensitivity associated with the neurons are specifically comodulated in parallel with the changes in number of antibody binding sites. The results suggest that at least a portion of the cross-reacting sites on the surface of ciliary ganglion neurons is likely to represent nicotinic ACh receptors. The fact that in some instances levels of ACh sensitivity can be altered without changing the number of cross-reacting sites, however, leaves open the possibility that not all of the sites are associated with receptors or that the neurons can alter the proportion of receptors that is functional. 相似文献
79.
David C. Dahlin M.D. Franco Bertoni M.D. John W. Beabout M.D. Mario Campanacci M.D. 《Skeletal radiology》1984,12(4):263-269
In a review of cases of fibrous cartilaginous dysplasia of bone, five of fibrocartilaginous lesions were found to be different in clinical behavior and radiographic and morphologic features from the others. We have named these previously undescribed tumors fibrocartilaginous mesenchymomas with low-grade malignancy in the fibrous elements.Dr. Bertoni is a visiting surgical pathologist from the Servizio di Anatomia ed Istologia Patologica, Bologna, Italy 相似文献
80.
Martina Meoli Franco Muggli Sebastiano A.G. Lava Mario G. Bianchetti Carlo Agostoni Claudine Kocher Thomas W. Bührer Letizia Ciliberti Giacomo D. Simonetti Gregorio P. Milani 《Nutrients》2021,13(5)
Vitamin D has been claimed to be effective in the response to infections, including the respiratory syndrome coronavirus 2 (SARS-CoV-2). It is supposed that lockdown measures and fear of SARS-CoV-2 infection might reduce vitamin D levels through the modification of lifestyle. However, very few data exist on the association between lockdown measures and vitamin D status in humans. For this cross-sectional comparative study, adolescents (n = 298) aged 18 to 19 years were enrolled during the compulsory military fitness-for-duty evaluation between July and December 2020 in Southern Switzerland. Beyond anthropometric measurements, participants filled in a structured questionnaire about their lifestyle and a blood specimen was sampled for the determination of total 25-hydroxy-vitamin D. The obtained data were compared with those of 437 adolescents enrolled at the military fitness-for-duty evaluation during the same period of the year in the context of the CENERI study (2014–2016). The anthropometric measures were similar between the two study groups. The levels of vitamin D were also comparable (77 (64–91) vs. 74 (60–92) nmol/L, p = 0.50; median and interquartile range). A total of 38 (13%) and 43 (9.8%) subjects presented insufficient (<50 nmol/L) levels of vitamin D (p = 0.42) during the current pandemic and in the CENERI study, respectively. These data do not support the hypothesis that during the SARS-CoV-2 pandemic, late adolescents are at higher risk of vitamin insufficiency. 相似文献