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11.
用电感耦合等离子体发射光谱法(ICP—AES),同时测定了广州与潮州产青果中13种微量元素和宏量元素的含量,结果发现其含有多种人体必需和与乙型肝炎的发生发展有关的微量元素;初步讨论了它们与青果功效的关系。  相似文献   
12.
Seventy five patients with acute and chronic active hepatitis (CAH) were studied by indirect immunofluorescence with monoclonal antibodies for the presence of hepatitis B surface antigen (HBsAg) on peripheral blood mononuclear cells (PBMC). The viral surface antigen was detected in the PBMC of all the patients with hepatitis B virus (HBV)-induced CAH and in acute patients with more than 2 months of evolution. No HBsAg was detected in the samples obtained from 12 normal controls or from 14 non-A, non-B CAH patients. Analysis of PBMC subsets revealed that HBsAg was present in non-T cells; dual fluorescence studies showed HBsAg on surface Ig-positive lymphocytes. The binding of anti-HBs monoclonal antibodies was higher than that of a goat anti-HBs serum, and the highest reactivity was observed with an antibody against the pre-S(2)-region sequence. Both HBsAg and hepatitis B core antigen (HBcAg) were also detected in lysates of PBMC by dot blot analysis.  相似文献   
13.
目的了解我市HIV、HCV、HBsAg、梅毒在一般献血人群的感染情况,确保输血安全。方法采用酶联免疫吸附试验检测抗-HIV、抗-HCV、HBsAg、RPR和TRUST试验检测梅毒。结果在献血人群中HBsAg阳性率为5.36%;抗-HCV阳性率为1.35%;梅毒阳性率为0.42%。结论多次献血者HBsAg检测阳性率较低;有献血浆史的献血者抗-HCV检测阳性显著高于一般人群。  相似文献   
14.
应用原位杂交和免疫组化PAP法双标记技术,结合病人乙型肝炎(乙肝)病毒血清学标志物检测结果,研究了31例慢性乙肝病人肝穿刺组织中乙型肝炎病毒DNA(HBV DNA)和HBsAg的分布及意义。结果显示,肝组织内检出HBV DNA 23例,HBsAg 26例,二者同时检出者21例。从同组病人肝组织内HBV DNA和HBsAg双标检测结果与其乙肝病毒血清学标志物检测结果的比较来看,肝组织内HBV DNA和HBsAg同时阳性很可能表明HBV正处于复制及表达的活动状态。  相似文献   
15.
A study involving more than 2,000 infants was conducted in Vietnam to assess the field effectiveness and immunogenicity of recombinant hepatitis B vaccine given at birth, 1 month, 2 months, without concomitant hepatitis B immune globulin (HBIG). All received a 5 microg dose of H-B-VAX II at birth. Infants born to non-carrier mothers (Group 1; N = 1798) then received 2.5 microg doses at 1 and 2 months of age, while infants of HBeAg-negative (Group 2; N = 125) or HBeAg-positive (Group 3; N = 88) carrier mothers received 5 microg doses. No Group 1 or 2 vaccinees were infected. In Group 3, 12 (14.6%) of 82 infants did become infected (estimated efficacy 84%). 98.0-98.6% of uninfected infants who were tested for anti-HBs developed a seroprotective concentration > or = 10 IU/L. In hyperendemic Vietnam, where routine maternal screening and passive-active prophylaxis of high-risk infants with vaccine plus HBIG is not feasible, administration of vaccine alone to all newborns may control effectively HBV infection.  相似文献   
16.
一步温育EIA法检测HBsAg   总被引:1,自引:0,他引:1  
缪慧  尹立志 《免疫学杂志》1995,11(3):194-197
本文报道用尼龙网为载体的抗HBsAg抗体膜作免疫吸附剂用于酶联免疫测定,对检测HBsAg的免疫反应程序和反应如酶标/抗原溶液配比量和温育反时间等进行了研究。结果得到一步温充EIA法的灵敏度与二步温育EIA法相比没有下降,检测时间由原来的约3h缩短至约50min。  相似文献   
17.
Summary A solid-phase radioimmunoassay was developed for the detection of HBeAg and anti-HBe in sera or serum fractions. HBe/sAg positive sera, partially purified HBeAg, partially purified HBsAg, and HBe/sAg negative sera were polymerized in polyacrylamide and compared for their ability to bind125I-IgG (anti-HBe). Only gels containing HBeAg reacted specifically with the iodinated antibody. The specificity of the binding was confirmed by blocking and inhibition tests using anti-HBe, HBeAg, HBsAg, and negative control sera. The radioimmunoassay allows the specific and quantitative detection of HBeAg and anti-HBe even in the presence of detergents and high salt concentrations.
Abbreviations HBsAg hepatitis B surface antigen - HBeAg hepatitis Be antigen - HBe/sAg hepatitis Be antigen and surface antigen - anti-HBe antibody to hepatitis Be antigen  相似文献   
18.
Israel has no official prevention policy at present against perinatal and horizontal transmission of hepatitis B virus (HBV) infection in newborns and children at risk. The present study was designed to assess the prevalence of HBV carrier state in a population of 11,123 pregnant women at term. Among this population (mean age 29.7 +/- 5.9), 98 women (0.88%) were found to be asymptomatic HBsAg+ carriers, and 97% of these carriers were anti-HBe+. Evidence for HBV replication, as determined by serum HBV-DNA, was established in 6.6% of the HBsAg+/anti-HBe+ population. The HBsAg carrier rate was strongly influenced by religion, continent, and country of birth of the carrier mothers. The highest relative carrier rate was found among women of Moslem origin (4.3%), as compared to Jewish women (0.67%). Most carrier women were born in Israel (56.1%) to mothers who had emigrated from regions with intermediate or high endemicity of HBV, such as North Africa or the Middle East. In these groups, the HBsAg carrier rate ranged between 1.2 and 3.0%. Ninety-three percent of newborns receiving passive/active vaccination against HBV developed protective levels of anti-HBs. Finally, evidence for horizontal transmission of HBV was found in 19.3% of 83 non-vaccinated children in families of HBsAg carriers. The present study therefore establishes HBsAg prevalence rates in specific risk groups of women at term and confirms the need for an official policy on immunization against HBV in Israel. Since over 50% of women at term belong to the defined risk groups, universal active vaccination of the entire newborn population each year is suggested as the most rational and needed policy in Israel.  相似文献   
19.
The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.  相似文献   
20.
The molecular basis of the d or y immunological subtype of hepatitis B virus (HBV) surface antigen (HBsAg) has been investigated by mutation of specific amino acid residues. When combined with substitution of serine 113 by threonine, replacement of arginine 122 by lysine or of tyrosine 134 by phenylalanine, or both of these changes, altered the antigenic subtype of HBsAg from y+d- to y+d+. These same mutations had a more dramatic effect on the subtype of antibodies induced by the antigens, a combination of all three mutations completely changing the subtype from y to d. Our study thus identifies residues in HBsAg that not only affect the subtype but discriminate between changes in antigenic and immunogenic behaviour. It also shows how the y and d subtypes may be manifest by the same molecule.  相似文献   
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