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991.
Konishi M Iwasa M Araki J Kobayashi Y Katsuki A Sumida Y Nakagawa N Kojima Y Watanabe S Adachi Y Kaito M 《Journal of gastroenterology and hepatology》2006,21(12):1821-1825
BACKGROUND: Oxidative stress plays an important role in the pathogenesis of chronic liver diseases. The plasma level of 8-isoprostane, a product of lipid peroxidation, is a marker of oxidative stress in vivo. The aim of the present study was to clarify whether the degree of lipid peroxidation, as measured by the plasma level of 8-isoprostane, influences the progression of chronic liver diseases and hepatocarcinogenesis. METHODS: Plasma 8-isoprostane levels were investigated in 14 patients with non-alcoholic fatty liver disease (NAFLD), 75 with chronic hepatitis C (CH-C), 14 with cured CH-C, 14 with HCV-positive hepatocellular carcinoma (HCC-C) and 38 healthy volunteers. 8-Isoprostane was measured by enzyme immunoassay after affinity column purification. RESULTS: Plasma 8-isoprostane was significantly elevated in NAFLD (11.9 [3.8-56.8] pg/mL), CH-C (10.1 [4.2-134.5] pg/mL) as compared to controls (6.3 [3.6-11.1] pg/mL). Plasma 8-isoprostane values were positively correlated with body mass index in NAFLD (P < 0.05) and with total cholesterol in cured CH-C (P < 0.01). 8-Isoprostane levels were not significantly related to sex, age, biochemical data or iron metabolism markers in all liver diseases. In addition, after the administration of peg-interferon, the values of 8-isoprostane improved in almost all patients, reaching values of healthy subjects. CONCLUSIONS: 8-Isoprostane values are elevated in patients with NAFLD and CH-C as compared to healthy controls. Oxidative stress caused by increased lipid peroxidation is involved in the pathogenesis of NAFLD and CH-C. 相似文献
992.
Iwasa K Takahashi T Nishiyama Y Moriyasu M Sugiura M Takeuchi A Tode C Tokuda H Takeda K 《Journal of natural products》2008,71(8):1376-1385
The combination of NMR, MS, and CD data permitted the structural elucidation including the absolute configuration of the known alkaloids and unknown components in the extract matrix solution of Nandina domestica without isolation and sample purification prior to the coupling experiments. Unstable natural stereoisomers were identified by LC-NMR and LC-MS. Five known alkaloids, (S)-isoboldine, (S)-domesticine, (S)-nantenine, sinoacutine, and menispermine, were identified from N. domestica. O-Methylpallidine and (E, E)-, (E, Z)-, and (Z, Z)-terrestribisamide were also characterized for the first time from this plant. Known jatrorrhizine, palmatine, and berberine and unknown (R)-carnegine and (E, E)-, (E, Z)-, and (Z, Z)-terrestribisamide were identified in the callus of N. domestica. 相似文献
993.
Yoshinobu Kanda Masahiro Kami Tomohiro Matsuyama Kinuko Mitani Shigeru Chiba Yoshio Yazaki Hisamaru Hirai 《Hematological oncology》1998,16(1):33-37
Fungal infection is a serious complication in immunocompromised patients, especially those with neutropenia. Itraconazole (ITZ) is expected to be an effective prophylactic agent for fungal infection because it has more activity against Aspergillus species than fluconazole and it is less toxic than amphotericin-B. However, ITZ is available only as an oral capsule, the absorption of which is thought to depend on the presence of acid in the stomach. In this study, the effect of famotidine, an H2-blocker, on the absorption of ITZ was investigated. Patients undergoing chemotherapy for hematological malignancies were enrolled. To minimize the effect of famotidine, the time of ITZ intake was different from that of famotidine intake. The plasma concentrations of ITZ with or without taking famotidine were determined just before and 4h after ITZ intake. Mean trough and peak concentrations of ITZ without famotidine were 332ng/ml and 476ng/ml, respectively. When famotidine was co-administered, the concentrations decreased to 204ng/ml and 315ng/ml, respectively. Statistical analyses revealed significant differences between trough concentrations in the presence and absence of famotidine (p=0·008). There was also a clear tendency toward higher peak concentrations in the plasma concentrations with famotidine (p=0·06). These findings suggest that famotidine decreases the plasma concentration of ITZ in patients undergoing chemotherapy. Close monitoring of the plasma concentration of ITZ and dose adjustment are required for efficient prophylaxis. Copyright © 1998 John Wiley & Sons, Ltd. 相似文献
994.
Nagata C Iwasa S Shiraki M Ueno T Uchiyama S Urata K Sahashi Y Shimizu H 《Cancer causes & control : CCC》2006,17(9):1107-1113
Absract
Objectives In utero exposure to high levels of endogenous estrogens has been hypothesized to increase breast cancer risk in later life.
A high intake of soy has been suggested to protect against breast cancer. We examined the hypothesis that maternal soy intake
may be inversely associated with pregnancy hormone levels.
Methods The concentrations of hormones (estradiol, estriol, and testosterone) and isoflavones (genistein, deidzein, and equol) were
measured in the maternal urine and serum, and umbilical cord blood of 194 women during pregnancy and at delivery. Soy intake
during pregnancy was assessed by 5-day diet records at approximately the 29th week of pregnancy.
Results High correlations were observed for isoflavone levels between maternal samples and umbilical cord blood, indicating that isoflavone
can be transferred from the maternal to the fetal compartment. None of the hormones measured in umbilical cord blood was significantly
associated with any of the isoflavones measured. There were a few significant associations between maternal hormone levels
and isoflavone measures during pregnancy, but their patterns of associations varied by gestational week and differed depending
on whether isoflavone exposure was measured by diet records, urine or serum.
Conclusion Our data contain no strong evidence showing that soy intake affects hormone levels during pregnancy. 相似文献
995.
Ken Kato Yuichiro Doki Takashi Ura Yasuo Hamamoto Takashi Kojima Takahiro Tsushima Shuichi Hironaka Hiroki Hara Toshihiro Kudo Satoru Iwasa Kei Muro Hirofumi Yasui Keiko Minashi Kensei Yamaguchi Atsushi Ohtsu Yuko Kitagawa 《Cancer science》2020,111(5):1676-1684
The long‐term efficacy of nivolumab in esophageal squamous cell carcinoma and its association with disease biomarkers are currently not well known. Therefore, we investigated the association in Japanese patients with treatment‐refractory advanced esophageal cancer who participated in an open‐label, single‐arm, multicenter phase II study. Patients received nivolumab 3 mg/kg i.v. every 2 weeks until disease progression or unacceptable toxicity, and were followed up for 2 years after the initial dosing of the last patient. Archival tissue samples were collected before treatment and analyzed for programmed death ligand‐1 (PD‐L1) and CD8+ status of tumors and tumor‐infiltrating lymphocytes (TILs) and human leukocyte antigen class 1. Efficacy end‐points included objective response rate (ORR), overall survival (OS), progression‐free survival (PFS), time to response, and duration of response. Of 65 enrolled patients (83% male), 64 were evaluable for efficacy and 41 (63%) for biomarkers. The ORR, median OS, and survival rate were 17.2%, 10.78 months, and 17.2%, respectively. Time to response was 1.45 months and duration of response was 11.17 months. The PD‐L1 positivity of tumor cells was possibly associated with better PFS (2.04 vs 1.41 months, cut‐off 1%) and OS (11.33 vs 6.24 months, cut‐off 1%). Median OS was prolonged in patients with a median number of TILs greater than 63.75% vs 63.75% or less (11.33 vs 7.85 months). Nivolumab showed continued long‐term efficacy, as seen by the stability of PFS and OS, in Japanese patients with esophageal squamous cell carcinoma. Further investigation of PD‐L1 tumor expression and TILs as potential biomarkers for predicting patients likely to benefit from nivolumab therapy is warranted. 相似文献
996.
997.
Takeshi Iwasa Toshiya Matsuzaki Kiyohito Yano Yiliyasi Mayila Minoru Irahara 《Gynecological endocrinology》2018,34(1):73-77
To clarify the direct effects of androgens, the changes in the hypothalamic levels of reproductive and appetite regulatory factors induced by chronic dihydrotestosterone (DHT) administration were evaluated in female rats. DHT treatment increased the BW and food intake of the ovariectomized rats, but not the estradiol (E2)-treated rats. DHT administration suppressed the expression of a hypothalamic anorexigenic factor. Although the kisspeptin (Kiss1) mRNA levels of the anterior hypothalamic block (the anteroventral periventricular nucleus, AVPV) were increased in the E2-treated rats, DHT administration did not affect the Kiss1 mRNA levels of the AVPV in the ovariectomized or E2-treated rats. Conversely, DHT administration reduced the Kiss1 mRNA levels of the posterior hypothalamic block (the arcuate nucleus, ARC) in the ovariectomized rats. Although the Kiss1 mRNA levels of the posterior hypothalamic block (ARC) were decreased in the E2-treated rats, DHT administration did not affect the Kiss1 mRNA levels of the ARC in these rats. Serum luteinizing hormone levels of these groups exhibited similar patterns to the Kiss1 mRNA levels of the ARC. These results showed that DHT affects the production of hypothalamic reproductive and appetite regulatory factors, and that these effects of DHT differ according to the estrogen milieu. 相似文献
998.
Katsumi Torigoe Sunao Sasaki Jun Hoshina Tsukasa Torigoe Moemi Hojo Shigehito Emura Kinuko Kojima Junya Onozuka Masatsugu Isobe Osamu Numata 《Pediatrics international》2011,53(4):446-453
Background: Children with a history of low birthweight (LBW) are often hospitalized with plural episodes of pneumonia after discharge from the neonatal intensive care unit. The aim of this study was to clarify the multiple factors predisposing them to developing three or more hospitalizations with pneumonia and whether the factors are related to their own prematurity. We also aimed to determine a predictable numerical formula for three or more episodes. Methods: Fourteen patients with two hospitalizations with pneumonia were grouped into group A. Fourteen patients with at least three episodes during the same investigation period were grouped into group B. The quantification theory type III was employed to investigate the similarities among the items and the gravity of each attribution in the two groups. To evaluate the items of discrimination of both groups, six items were analyzed by the quantification theory type II. Results: The dominant order of items contributing to the grouping was as follows: methicillin‐resistant staphylococcus aureus detection (partial correlation coefficient = 0.5284), asthmatic attack (partial correlation coefficient = 0.4138), severe motor and intellectual disability, Haemophilus influenzae, accompanying diseases and chronic lung disease. A predicting numerical formula was attained from these results. The success rate of discrimination was 85.7%. The six items seemed to be related to the patients' own prematurity. Conclusions: The authors emphasize that plural hospitalizations with pneumonia in the patients with LBW might be caused by the combined influence of six clinical factors as well as their own prematurity. 相似文献
999.