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E Mix T Olsson J Correale S Baig V Kostulas O Olsson H Link 《Clinical and experimental immunology》1990,79(1):21-27
By two-colour flow cytometric analysis, we found increased numbers of B cells co-expressing the pan-T cell marker CD5 and the B cell marker CD19 in cerebrospinal fluid (CSF) of 21 patients with multiple sclerosis (MS), compared with 17 control subjects with muscular tension headache. Only one patient with MS, but nine controls lacked CD5+ B cells in CSF. This difference was not observed in peripheral blood. Numbers of CD5+19+ B cells were increased in CSF compared with blood in MS, but not in the controls. In both groups, CD5+19+ B cells were not restricted to small resting lymphocytes, but were also found among larger-sized lymphocytes. The relative density of CD5 molecules and of CD19 molecules was lower in CD5+19+ than in CD5-19+ B cells and CD5+19- T cells. CD5+ B cells are assumed to be responsible for autoantibody production, and our results suggest a pathogenetic role of such cells, predominantly within the central nervous system, in MS. 相似文献
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Extracellular neuraminidase production by group A streptococci was examined in 92 strains. Fourteen of these strains produced appreciable amounts of enzyme; 12 of the neuraminidase-producing strains belonged to T types 1, 4, and 12. Production of the enzyme paralleled bacterial growth in culture and was maximal in medium containing 0.2% glucose. The enzyme produced by one of these strains was partially purified by ammonium sulfate fractionation and filtration on G-200 Sephadex. Its molecular weight was estimated at 90,000. Activity was optimal at pH 5.7 and in the presence of 0.01 to 0.03 M calcium and magnesium cations. The enzyme was stable at temperatures of 4 and 37 degrees C for at least 24 h but was inactivated within 10 min at temperatures of 50 and 65 degrees C. The enzyme hydrolyzed 40% of the sialic acid in bovine submaxillary mucin, but was inactive on sialyl-lactose, porcine submaxillary mucin, oligosaccharides derived from porcine mucin, or human orosomucoid. The Km value for this enzyme with bovine submaxillary mucin as substrate was in the order of 3.6 x 10(-4) M. 相似文献
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Munaza Fatima Santosh Kumar Mudassar Hussain Naveed Masood Memon Anum Vighio Muhammad Asif Syed Ambreen Chaudhry Zakir Hussain Zeeshan Iqbal Baig Mirza Amir Baig Rana Jawad Asghar Aamer Ikram Yousef Khader 《JMIR Public Health and Surveillance》2021,7(5)
BackgroundHyderabad, Pakistan, was the first city to witness an outbreak of extensively drug resistant (XDR) typhoid fever. The outbreak strain is resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, fluoroquinolones, and third-generation cephalosporin, thus greatly limiting treatment options. However, despite over 5000 documented cases, information on mortality and morbidity has been limited.ObjectiveTo address the existing knowledge gap, this study aimed to assess the morbidity and mortality associated with XDR and non-XDR Salmonella serovar Typhi infections in Pakistan.MethodsWe reviewed the medical records of culture-confirmed typhoid cases in 5 hospitals in Hyderabad from October 1, 2016, to September 30, 2018. We recorded data on age, gender, onset of fever, physical examination, serological and microbiological test results, treatment before and during hospitalization, duration of hospitalization, complications, and deaths.ResultsA total of 1452 culture-confirmed typhoid cases, including 947 (66%) XDR typhoid cases and 505 (34%) non-XDR typhoid cases, were identified. Overall, ≥1 complications were reported in 360 (38%) patients with XDR typhoid and 89 (18%) patients with non-XDR typhoid (P<.001). Ileal perforation was the most commonly reported complication in both patients with XDR typhoid (n=210, 23%) and patients with non-XDR typhoid (n=71, 14%) (P<.001). Overall, mortality was documented among 17 (1.8%) patients with XDR S Typhi infections and 3 (0.6%) patients with non-XDR S Typhi infections (P=.06).ConclusionsAs this first XDR typhoid outbreak continues to spread, the increased duration of illness before hospitalization and increased rate of complications have important implications for clinical care and medical costs and heighten the importance of prevention and control measures. 相似文献
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Metastable Equilibrium Solubility Behavior of Bone Mineral 总被引:1,自引:1,他引:0
Baig AA Fox JL Wang Z Higuchi WI Miller SC Barry AM Otsuka M 《Calcified tissue international》1999,64(4):329-339
Previous studies have shown that carbonated apatites with a range of carbonate contents and crystallinities exhibit the phenomenon
of metastable equilibrium solubility (MES) distributions. The purpose of the present study was to investigate the solubility
behavior of bone mineral using the concepts of MES and MES distributions and, together with crystallinity and chemical composition
data, examine the similarity of bone mineral to carbonated apatite (CAP). Bone samples were harvested from 1-, 5-, and 8-month-old
rats. The organic components of the bone samples were removed by hydrazine deproteination. Carbonated apatite was synthesized
by the hydrolysis of dicalcium phosphate dihydrate (DCPD) in a NaHCO3-containing media at 50°C. The MES distributions of bone mineral and CAP were determined by equilibrating predetermined amounts
of CAP or bone mineral in a series of 0.1 M acetate buffers containing calculated levels of calcium and phosphate and maintained
at essentially constant pHs of 5.0, 5.3, 5.7, and 6.5. From the compositions of the equilibrating buffer solutions, ion activity
products based upon the stoichiometries of octacalcium phosphate, hydroxyapatite, and carbonated apatite were calculated in
an attempt to determine the function governing the dissolution of CAP and bone mineral. The results of this study demonstrated
that the MES distribution phenomenon appeared to hold for bone mineral and that the changes in crystallinity of bone mineral
with age correlated well with changes in the MES values. A CAP sample was prepared that was found to be an excellent synthetic
prototype closely mimicking the physicochemical behavior of bone mineral from an 8-month-old rat. Another finding of this
study was that the ion activity product function based upon the hydroxyapatite stoichiometry well described the MES results
obtained with both CAP and bone mineral. The interpretation that a surface complex with hydroxyapatite stoichiometry governs
the solubility behavior of bone mineral is, therefore, consistent with the experimental data. Other calcium phosphate stoichiometries
for the surface complex showed systematic variations in the MES profiles when the pH of the equilibrating solution was varied.
Received: 30 October 1997 / Accepted: 1 October 1998 相似文献
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Obstetric outcome in 232 ovum donation pregnancies 总被引:3,自引:0,他引:3
Hossam I. Abdalla Consultant Anne Billett Clinical Research Fellow rew K. S. Kan Clinical Research Fellow Sabah Baig Clinical Research Fellow Marie Wren Infertility Specialist Lena Korea Ovum Donation Co-ordinator John W. W. Studd Consultant 《BJOG : an international journal of obstetrics and gynaecology》1998,105(3):332-337
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