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61.
Purpose
The effects of mild and moderate hypothermic therapy on cerebral injury are still controversial. Our hypothesis is that mild and moderate hypothermia should have some effects on neurons themselves if they really have protective effects. By using a nearly pure neuronal culture, we evaluated the effects and mechanism of hypothermia against hypoxic insult. 相似文献62.
Koji Tanaka MD Isao Miyashiro MD Masahiko Yano MD Kentaro Kishi MD Masaaki Motoori MD Yousuke Seki MD Shingo Noura MD Masayuki Ohue MD Terumasa Yamada MD Hiroaki Ohigashi MD Osamu Ishikawa MD 《Annals of surgical oncology》2009,16(6):1520-1525
Background The effect of obesity on gastrectomy in patients with gastric cancer is controversial. The degree of abdominal fat increases
the technical difficulty of abdominal surgery. This study examined the effect of visceral fat on total gastrectomy and risk
factors associated with the formation of pancreatic fistula.
Methods Between February 2001 and April 2007, 191 patients with gastric cancer underwent total gastrectomy. The visceral fat area
(VFA) was calculated from computed tomography (CT) scans taken at the level of the umbilicus using FatScan Software. Patients
were divided into high- (≥100 cm2, n = 52) and low-VFA groups (<100 cm2, n = 139), and also into high- (≥25 kg/m2, n = 47) and low-BMI groups (<25 kg/m2, n = 144).
Results Blood loss and incidence of pancreatic fistula were significantly higher in the high- than low-VFA group. However, only blood
loss was significantly different between the high- and low-BMI groups. VFA, blood loss, and splenectomy were identified as
significant risk factors for pancreatic fistula formation on univariate analysis, and multivariate logistic regression analysis
of these factors identified VFA (p = 0.0001) and splenectomy (p = 0.0014) as significant predictors of pancreatic fistula.
Conclusions VFA is a better indicator for pancreatic fistula formation after total gastrectomy than is BMI. Lymph node dissection must
be performed carefully, especially in patients with visceral fat accumulation during total gastrectomy with splenectomy. 相似文献
63.
Seo A Fujii T Inoue T Onoda S Koga A Tanaka Y Chin K Kurusu T Takikawa K Shibata T Taniguchi M Mochizuki S 《International heart journal》2007,48(2):137-147
The aim of this study was to compare the initial and long-term outcomes of sirolimus-eluting stents (SES) and bare-metal stents (BMS) in patients with calcified lesions without performing rotational atherectomy. The subjects were 79 consecutive lesions (38 in the SES group and 41 in the BMS group) which were confirmed to have superficially calcified lesions by intravascular ultrasound. In all lesions, the stent was implanted after predilatation with a balloon. The patient characteristics were not different between the 2 groups. All procedures were successfully performed in both groups. Vessel area was significantly smaller in the SES group than in the BMS group (11.01 +/- 3.88 mm(2) versus 13.08 +/- 3.49 mm(2), P < 0.005), as was the lumen area (5.41 +/- 2.31mm(2) versus 6.48 +/- 2.04 mm(2), P < 0.005). Minimum stent area was significantly smaller in the SES group than in the BMS group (5.61 +/- 1.54 mm(2) versus 6.69 +/- 1.74 mm(2), P < 0.01). In cases in whom angiographic follow-ups were performed, the late loss was significantly smaller in the SES group than in the BMS group (0.19 +/- 0.49 mm versus 0.76 +/- 0.48 mm, P < 0.001). The restenosis rate was significantly lower in the SES group than in the BMS group (8.8% versus 33.3%, P < 0.05) and the TLR rate tended to be lower in the SES group (7.9% versus 19.5%). Stent thrombosis was not observed in either group. The results suggest that SES are more effective than BMS and can be used safely when treating calcified lesions if predilatation with a balloon is possible. 相似文献
64.
65.
Intraductal papillary-mucinous carcinoma of the pancreas with tumor thrombus in the portal vein: a report of two cases 总被引:1,自引:0,他引:1
Tomimaru Y Ishikawa O Ohigashi H Eguchi H Yamada T Sasaki Y Kishi K Takachi K Noura S Miyashiro I Ohue M Yano M Imaoka S 《Hepato-gastroenterology》2007,54(77):1585-1588
Intraductal papillary-mucinous carcinoma (IPMC) is a recently recognized pancreatic tumor and this is the first report to present two patients with IPMC complicating tumor thrombi in the portal vein. Two women, a 74- and a 55-year-old, each revealed a round, cystic and well-demarcated tumor of the pancreas in an abdominal computed tomography (CT). However, the inner lumen of the splenic and portal veins was insufficiently stained during iv-infusion of the contrast medium, suggesting the presence of tumor thrombi. Owing to this information, the presence of tumor thrombus was investigated and correctly identified during laparotomy, and it was completely removable together with the primary pancreatic tumor. The resected tumors showed expansive growth because mucin and tumor tissues rose up when they were cut. Microscopically, the tumor was diagnosed as adenocarcinoma without ovarian-like stroma, and the final diagnosis of branch type of IPMC was made for the two patients. However, within one postoperative year, both patients developed liver metastasis. Although IPMC is known as having a lower potential for metastasis or invasion, the tumor thrombi can form when it reveals an expansive growth suggesting a high inner pressure. In addition, a higher possibility for subsequent liver metastasis should be anticipated after the tumor forms a thrombus in the portal vein. 相似文献
66.
67.
Okada T Liew CW Hu J Hinault C Michael MD Krtzfeldt J Yin C Holzenberger M Stoffel M Kulkarni RN 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(21):8977-8982
Insulin and insulin-like growth factor 1 (IGF1) are ubiquitous growth factors that regulate proliferation in most mammalian tissues including pancreatic islets. To explore the specificity of insulin receptors in compensatory beta-cell growth, we examined two models of insulin resistance. In the first model, we used liver-specific insulin receptor knockout (LIRKO) mice, which exhibit hyperinsulinemia without developing diabetes due to a compensatory increase in beta-cell mass. LIRKO mice, also lacking functional insulin receptors in beta-cells (beta IRKO/LIRKO), exhibited severe glucose intolerance but failed to develop compensatory islet hyperplasia, together leading to early death. In the second model, we examined the relative significance of insulin versus IGF1 receptors in islet growth by feeding high-fat diets to beta IRKO and beta-cell-specific IGF1 receptor knockout (beta IGFRKO) mice. Although both groups on the high-fat diet developed insulin resistance, beta IRKO, but not beta IGFRKO, mice exhibited poor islet growth consistent with insulin-stimulated phosphorylation, nuclear exclusion of FoxO1, and reduced expression of Pdx-1. Together these data provide direct genetic evidence that insulin/FoxO1/Pdx-1 signaling is one pathway that is crucial for islet compensatory growth response to insulin resistance. 相似文献
68.
Kobayashi H Kusafuka J Lane GJ Yamataka A Satoh K Hayakawa T Kase Y Hatano M 《Journal of pediatric surgery》2007,42(12):2062-2066
Purpose
Homozygous mutant Ncx/Hox11L.1-deficient (Ncx−/−) mice develop mega-ileo-ceco-colon with a caliber change in the proximal colon. This study investigated the mechanism of intestinal motility in these mice.Method
Five-week-old male and female Ncx−/− mice with mega-ileo-ceco-colon (n = 8) were compared with age-matched male BDF1 mice used as controls (n = 8). All mice were sacrificed, and uniform-sized strips of jejunum, ileum, proximal colon, and distal colon were exposed to electrical field stimulation and pretreatment with atropine sulfate, guanethidine, or tetrodotoxin. Contractile responses were recorded and compared.Results
Longitudinal muscle from strips of jejunum and ileum from all mice (BDF1 and Ncx−/−) did not respond to electrical field stimulation, whereas ileal circular muscle contracted in BDF1 mice and contracted and relaxed in Ncx−/− mice. Pretreatment with atropine sulfate and guanethidine inhibited the responses of circular muscle of distal colon and ileum in BDF1 mice significantly (P < .05), but no effect was observed in Ncx−/− mice.Conclusion
In ileum, BDF1 mice have cholinergic and adrenergic dominant contraction patterns, whereas Ncx−/− mice have relaxation-dominant patterns because of nonadrenergic, noncholinergic nerves. Based on this, there would appear to be some kind of variation in the gastrointestinal nerve supply in Ncx−/− mice. 相似文献69.
Olfactory information is initially processed through intricate synaptic interactions between glutamatergic projection neurons and GABAergic interneurons in the olfactory bulb. Although bulbar neurons and networks have been reported to develop even postnatally, much is yet unknown about the glutamatergic neuron development. To address this issue, we studied the postnatal ontogeny of vesicular glutamate transporters (VGLUT1 and VGLUT2) in the main olfactory bulb of rats, using in situ hybridization, immunohistochemistry, and their combination. In situ hybridization data showed that VGLUT1 mRNA is intensely expressed in differentiating mitral cells and smaller cells of the mitral cell layer (MCL) on postnatal day 1 (P1), and also at lower levels in small- and medium-sized cells, presumably tufted cell populations, of the external plexiform layer (EPL) from P5 onward. VGLUT2 mRNA was expressed in many MCL cell populations on P1, also in small- and medium-sized cells of the EPL at almost the same level as MCL cells between P5 and P7, and became apparently less intense in the MCL than in the EPL from P10 onward. The expression, unlike VGLUT1 mRNA, was also found in small-sized cells of the interglomerular region. In partial agreement with these data, immunohistochemical analyses demonstrated that subsets of mitral and EPL cells are stained for VGLUT1 or VGLUT2, with the former cells coexpressing both subtypes until P5. Moreover, a combined fluorescence in situ hybridization–immunohistochemical dual labeling of the P10 bulb revealed that neither VGLUT1 nor VGLUT2 mRNA is expressed in GABAergic or dopaminergic periglomerular cells, implying their expression in other periglomerular cell subclasses, external tufted cells and/or short-axon cells. Thus, the present study suggests that early in the postnatal development distinct glutamatergic bulbar neurons of rats express spatiotemporally either or both of the two VGLUT subtypes as a specific vesicular transport system, specifically contributing to glutamate-mediated neurobiological events. 相似文献
70.
Koushi Yamaguchi Michi Hisano Sakiko Isojima Seiko Irie Naoko Arata Noriyoshi Watanabe Takahiko Kubo Tatsuo Kato Atsuko Murashima 《Journal of medical virology》2009,81(11):1923-1928
To determine the optimal timing for influenza vaccination in pregnant women, we measured alterations in the types 1 and 2 T helper cell (Th1/Th2) balance during pregnancy, monitored specific immunity to inoculated antigens after vaccination with inactivated influenza vaccine, evaluated the relevance of the Th1/Th2 ratio and immune responses to the vaccination, monitored the maintenance of high antibody titers until delivery and measured the transplacental antibody transfer rate. No significant alterations of the Th1/Th2 balance were noted in the 65% of pregnant women among whom the Th1/Th2 ratio was lower than 9.9% in the first trimester. In those groups with a ratio higher than 10% in the first trimester, there was a tendency for the ratio to decrease as gestation advanced. The efficiency of immunization was not influenced by the Th1/Th2 status or by the stage of gestation. The antibody titer decreased steadily with time from 1 month after vaccination to the time of delivery. Conversely, the transfer rate of antibodies from maternal to fetal blood at the time of delivery increased with the duration of gestation after vaccination. Nevertheless, the antibody titers in both maternal and fetal blood were sufficient to afford protection against infection. Thus, efficient influenza vaccination can be undertaken at any stage of pregnancy. J. Med. Virol. 81:1923–1928, 2009. © 2009 Wiley‐Liss, Inc. 相似文献