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101.
Functional abnormalities of heparan sulfate in mucopolysaccharidosis-I are associated with defective biologic activity of FGF-2 on human multipotent progenitor cells
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Pan C Nelson MS Reyes M Koodie L Brazil JJ Stephenson EJ Zhao RC Peters C Selleck SB Stringer SE Gupta P 《Blood》2005,106(6):1956-1964
In mucopolysaccharidosis-I (MPS-I), alpha-L-iduronidase deficiency leads to progressive heparan sulfate (HS) and dermatan sulfate (DS) glycosaminoglycan (GAG) accumulation. The functional consequences of these accumulated molecules are unknown. HS critically influences tissue morphogenesis by binding to and modulating the activity of several cytokines (eg, fibroblast growth factors [FGFs]) involved in developmental patterning. We recently isolated a multipotent progenitor cell from postnatal human bone marrow, which differentiates into cells of all 3 embryonic lineages. The availability of multipotent progenitor cells from healthy volunteers and patients with MPS-I (Hurler syndrome) provides a unique opportunity to directly examine the functional effects of abnormal HS on cytokine-mediated stem-cell proliferation and survival. We demonstrate here that abnormally sulfated HS in Hurler multipotent progenitor cells perturb critical FGF-2-FGFR1-HS interactions, resulting in defective FGF-2-induced proliferation and survival of Hurler multipotent progenitor cells. Both the mitogenic and survival-promoting activities of FGF-2 were restored by substitution of Hurler HS by normal HS. This perturbation of critical HS-cytokine receptor interactions may represent a mechanism by which accumulated HS contributes to the developmental pathophysiology of Hurler syndrome. Similar mechanisms may operate in the pathogenesis of other diseases where structurally abnormal GAGs accumulate. 相似文献
102.
Epstein-Barr virus-associated gastric carcinoma: Evidence of age-dependence among a Mexican population 总被引:3,自引:0,他引:3
Herrera-Goepfert R Akiba S Koriyama C Ding S Reyes E Itoh T Minakami Y Eizuru Y 《World journal of gastroenterology : WJG》2005,11(39):6096-6103
AIM: To investigate features of Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) among a Mexican population. METHODS: Cases of primary gastric adenocarcinoma were retrieved from the files of the Departments of Pathology at the Instituto Nacional de Cancerologia and the Instituto Nacional de la Nutricion in Mexico City. The anatomic site of the gastric neoplasia was identified, and carcinomas were histologically classified as intestinal and diffuse types and subclassified as proposed by the Japanese Research Society for Gastric Cancer. EBV-encoded small non-polyadenylated RNA-1 (EBER-1) in situ hybridization was conducted to determine the presence of EBV in neoplastic cells. RESULTS: We studied 330 consecutive, non-selected, primary gastric carcinomas. Among these, there were 173 male and 157 female patients (male/female ratio 1.1/1). EBER-1 was detected in 24 (7.3%) cases (male/female ratio: 1.2/1). The mean age for the entire group was 58.1 years (range: 20-88 years), whereas the mean age for patients harboring EBER-1-positive gastric carcinomas was 65.3 years (range: 50-84 years). Age and histological type showed statistically significant differences, when EBER-1-positive and -negative gastric carcinomas were compared. EBER-1 was detected in hyperplastic- and dysplastic-gastric mucosa surrounding two EBER-1-negative carcinomas, respectively. CONCLUSION: Among Latin-American countries, Mexico has the lowest frequency of EBVaGC. Indeed, the Mexican population >50 years of age was selectively affected. Ethnic variations are responsible for the epidemiologic behavior of EBVaGC among the worldwide population. 相似文献
103.
Andrea Kim Kimberly Page-Shafer Juan Ruiz Lisa Reyes Viva Delgado Jeffrey Klausner Fred Molitor Mitchell Katz William McFarland 《AIDS and behavior》2002,6(4):331-338
HIV risk was assessed in association with a history of incarceration and having a sexual partner with a history of incarceration in a population sample of low-income young women residing in San Francisco. Of the 235 women surveyed, 23% reported prior incarceration and 42% reported having a sexual partner with a history of incarceration. Prevalence of sexually transmitted infections (STIs) (including HIV) was no higher among previously incarcerated women or those with a sexual partner with a history of incarceration. Women with a prior incarceration were significantly more likely to report injecting drugs, exchanging sex for money or drugs, and history of forced sex. Women reporting sexual partners with a history of incarceration were significantly more likely to report incarceration history, history of STIs, and history of forced sex. Interventions aimed at reducing substance abuse, STIs, commercial/survival sex, and the effects of sexual coercion need to be strengthened for women within and transitioning out of correctional facilities. 相似文献
104.
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107.
Garcia Cecilia C. Piotrkowski Bárbara Baz Plácida Poncino Daniel Benavides Javier Colombato Luis Toso María Laura Reyes Yantorno Silvina Descalzi Valeria Gondolesi Gabriel E. Fraga Cesar G. Cherñavsky Alejandra C. 《Digestive diseases and sciences》2022,67(7):3006-3016
Digestive Diseases and Sciences - Deregulation of immune response and oxidative stress contribute to nonalcoholic fatty liver disease (NAFLD) pathogenesis. Resistin is a physiological modulator of... 相似文献
108.
109.
Candela F Serrano P Arriero JM Teruel A Reyes D Calpena R 《Diseases of the colon and rectum》1999,42(1):110-112
PURPOSE: A case of anal tuberculosis in an otherwise asymptomatic patient with bleeding anal ulcers is presented. The clinical features of this entity and the problems in differential diagnosis between anal infectious vs. inflammatory diseases are discussed. METHODS: The management and outcome of the case of an adult patient who presented with perianal ulcers is described. RESULTS: On a three-drug antituberculous regimen, symptoms abated, radiographic infiltrates improved, and perianal ulcers healed. CONCLUSION: Anal tuberculosis is an extremely rare disease. A tuberculous origin must be considered when the cause of perianal ulcers is unclear to avoid undesirable delays in the diagnosis and treatment of this disease. 相似文献
110.
Joaquín Palma Humberto Reyes José Ribalta Ismael Hernández Lorena Sandoval Ramón Almuna Juris Liepins Fernando Lira Manuel Sedano Octavio Silva Dolores Tohá Juan Jorge Silva 《Journal of hepatology》1997,27(6):1022-1028
Backgrounds/Aims: Intense pruritus and the risk of stillbirths and premature deliveries justify the search for an effective pharmacologic treatment of intrahepatic cholestasis of pregnancy. This study was designed to test the efficacy of ursodeoxycholic acid in maternal pruritus, the biochemical abnormalities and the outcome of pregnancy, in patients with intrahepatic cholestasis of pregnancy of early onset.Methods: Pregnant patients hospitalized in a secondary case-referral center with intense pruritus and abnormal serum levels of bile salts and aminotransferases, detected before week 33 of pregnancy, were randomly assigned to receive ursodeoxycholic acid, 1 g per day orally, or an identical placebo, until delivery, in a double-blind study. A 3-week trial period was chosen to compare drug and placebo effects. The follow-up was extended for 3 months after delivery.Results: Twenty-four patients entered the trial; eight had deliveries before 2 weeks of treatment and one dropped out. The study was then completed in 15 patients: eight received ursodeoxycholic acid and seven placebo. No adverse effects were detected in the mother or in their babies. After 3 week of treatment, patients receiving ursodeoxycholic acid (mean daily) dose 16 mg/kg body weight) had a significant improvement in pruritus (p<0.02), In serum bilirubin (0.36±0.19 mg/dl (mean±SD) versus 0.95±0.48 in patients receiving placebo, p<0.01), in aspartate aminostransferase (52±42 IU/l vs 98±44, p<0.05) and in alanine aminotransferase (54±50 IU/l vs 229±154, p<0.01); serum total bile salts also tended to be lower in patients receiving ursodeoxycholic acid (26.3±33.7 μmol/l vs 55.0±44.8, p N.S.). Deliveries occurred at or near term in all mothers who received ursodeoxycholic acid (mean week of pregnancy: 38), while they occurred before week 36 of pregnancy in five patients who received placebo, including one stillbirth. All babies born alive had birth weights adequate for gestational age and they were thriving normally 3 months after delivery.Conclusions: Ursodeoxycholic acid is effective and safe in patients with intrahepatic cholestasis of pregnancy of early onset, attenuating pruritus and correcting some biochemical abnormalities in the mothers. Relevant aspects of fetal outcome were also improved in patients receiving ursodeoxycholic acid compared to placebo. 相似文献