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981.
Dr. Toshio Watanabe MD Tetsuo Arakawa MD PhD Takashi Fukuda MD PhD Kazuhide Higuchi MD PhD Kenzo Kobayashi MD PhD 《Digestive diseases and sciences》1995,40(6):1340-1344
Zinc is an important element in wound healing. Zinc compounds hasten the healing of gastric ulcers, by an unknown mechanism(s). We studied the effect of the induction of zinc deficiency on gastric ulcer healing. Rats were given a control or zinc-deficient diet for six weeks and then subjected to the induction of acetic acid-induced chronic gastric ulcers. Four days later, zinc-deficient rats were divided into two groups. In the first group, the zinc-deficient diet was continued. In the second group, the diet was changed to the control diet. Zinc-deficient rats had a mean serum zinc concentration approximately 70% of that in controls. Zinc deficiency did not affect the formation of gastric ulcers; however, it reduced cell proliferation by day 4 and delayed ulcer healing. Zinc supplementation brought zinc to control levels within a week, but failed to reverse the delay in ulcer healing. We conclude that zinc is crucial for healing of gastric ulcers, especially at the early stage.An abstract of this study was presented at the Second Osaka International Symposium on Gastroenterology held in Osaka, Japan, on November 22–23, 1993. 相似文献
982.
Changes in the cardiac sarcolemma in myocardial infarction were studied by both determination of Na+-K+-ATPase activity and SDS gel electrophoretic analysis of sarcolemmal proteins in the canine heart. Ninety minutes after coronary ligation, Na+-K+-ATPase activity in ischemic myocardium was decreased significantly to approximately 36% of that of non-ischemic myocardium, and it remained at the lower level for 28 days. By SDS gel electrophoresis, reduction of the protein band with molecular weight of 111,000, which is suggestive of the main component of ATPase, was observed simultaneously with the reduction of Na+-K+-ATPase activity. These results indicate that ischemia for 90 minutes produces substructural changes in the sarcolemma indicating irreversible myocardial changes. 相似文献
983.
Hepatic lipase gene therapy in hepatic lipase-deficient mice. Adenovirus-mediated replacement of a lipolytic enzyme to the vascular endothelium. 下载免费PDF全文
D Applebaum-Bowden J Kobayashi V S Kashyap D R Brown A Berard S Meyn C Parrott N Maeda R Shamburek H B Brewer Jr S Santamarina-Fojo 《The Journal of clinical investigation》1996,97(3):799-805
Hepatic lipase (HL) is an endothelial-bound lipolytic enzyme which functions as a phospholipase as well as a triacylglycerol hydrolase and is necessary for the metabolism of IDL and HDL. To evaluate the feasibility of replacing an enzyme whose in vivo physiologic function depends on its localization on the vascular endothelium, we have infused recombinant replication-deficient adenovirus vectors expressing either human HL (HL-rAdV; n = 7) or luciferase cDNA (Lucif-rAdV; n = 4) into HL-deficient mice with pretreatment plasma cholesterol, phospholipid, and HDL cholesterol values of 176 +/- 9, 314 +/- 12, and 129 +/- 9, respectively. After infusion of HL-rAdV, HL could be detected in the postheparin plasma of HL-deficient mice by immunoblotting and postheparin plasma HL activities were 25,700 +/- 4,810 and 1,510 +/- 688 nmol/min/ml on days 5 and 15, respectively. Unlike the mouse HL, 97% of the newly synthesized human HL was heparin releasable, indicating that the human enzyme was virtually totally bound to the mouse vascular endothelium. Infusion of HL-rAdV in HL-deficient mice was associated with a 50-80% decrease in total cholesterol, triglyceride, phospholipids, cholesteryl ester, and HDL cholesterol (P < 0.001) as well as normalization of the plasma fast protein liquid chromatography lipoprotein profile by day 8. These studies demonstrate successful expression and delivery of a lipolytic enzyme to the vascular endothelium for ultimate correction of the HL gene defect in HL-deficient mice and indicate that recombinant adenovirus vectors may be useful in the replacement of endothelial-bound lipolytic enzymes in human lipolytic deficiency states. 相似文献
984.
Regulation by endogenous interleukin-1 of mRNA expression of healing-related factors in gastric ulcers in rats. 总被引:5,自引:0,他引:5
S Takahashi N Kobayashi S Okabe 《The Journal of pharmacology and experimental therapeutics》1999,291(2):634-641
We investigated the role of endogenous interleukin (IL)-1 in the mRNA expression of cyclooxygenase (COX)-1, COX-2, inducible nitric oxide synthase (iNOS), cytokine-induced neutrophil chemoattractant (CINC)-1, epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), and transforming growth factor (TGF)-beta1 in acetic acid-induced gastric ulcers in rats. IL-1beta mRNA was not detected in the normal or intact mucosa of ulcerated stomachs, but its expression was induced in the ulcerated tissue. IL-1beta immunoreactivity was observed in macrophages/monocytes and fibroblasts in the ulcer base. COX-2, iNOS, and CINC-1 mRNAs were expressed by ulceration. EGF, bFGF, HGF, and TGF-beta1 mRNA expression was detected in the normal mucosa, and their levels were significantly elevated by ulceration. In contrast, COX-1 mRNA level did not differ between the normal and ulcerated tissues. In a culture of isolated ulcer bases, block of IL-1 with IL-1 receptor antagonist (IL-1RA) dose-dependently and significantly reduced the mRNA levels of COX-2, iNOS, CINC-1, HGF, and bFGF. In contrast, COX-1, EGF, and TGF-beta1 mRNA expression was not affected by IL-1RA. IL-1RA dose-dependently reduced prostaglandin E(2) production, total and iNOS activities, neutrophil chemotactic activity, and growth-promoting activity toward gastric epithelial cells in the ulcer base. Finally, the administration of IL-1RA caused a significant impairment of ulcer healing. These results indicate that IL-1, expressed in macrophages/monocytes and fibroblasts in the ulcer base, might up-regulate the mRNA expression of COX-2, iNOS, CINC-1, HGF, and bFGF, thereby contributing to gastric ulcer healing in rats. 相似文献
985.
S. Gando S. Nanzaki Y. Morimoto S. Kobayashi O. Kemmotsu 《Intensive care medicine》1999,25(6):588-593
Objective: To investigate the relationship between cytokines and the inflammatory responses in patients with out-of-hospital cardiac
arrest, we examined the changes of cytokines as well as alterations in the markers of neutrophil activation, platelet and
endothelial activation, and endothelial injury. Design: Prospective, cohort study. Setting: General intensive care unit of a tertiary care center. Patients and participants: 26 out-of-hospital cardiac arrest patients were classified into two groups: those who achieved return of spontaneous circulation
(ROSC) (n = 10) and those with no ROSC (n = 16). Eight normal healthy volunteers served as control subjects. Measurements and results: Serial levels of soluble L-selectin (sL-selectin), soluble P-selectin (sP-selectin), neutrophil elastase, and soluble thrombomodulin
were measured during and after cardiopulmonary resuscitation (CPR). Serial levels of tumor necrosis factor α (TNFα) and interleukin-1β (IL-1β) were also measured. We could not find any elevations in either cytokine during the study period. In both groups, sP-selectin
levels were significantly higher than those in control subjects from the time of arrival at the emergency department to 24
h after admission. sL-selectin levels in the two groups were markedly lower compared to those in control subjects at all sampling
points. In patients with ROSC, cardiac arrest and CPR led to an increase in the levels of neutrophil elastase and soluble
thrombomodulin that peaked 6 h or 24 h after arrival at the emergency department. No statistical differences in the levels
of the two selectins, neutrophil elastase, and soluble thrombomodulin between the two groups were found during CPR. Conclusions: Out-of-hospital cardiac arrest and CPR induces platelet, neutrophil, and endothelial activation and is associated with endothelial
injury. Inflammatory cytokines may not have an important role in human whole-body ischemia-reperfusion injury.
Received: 2 November 1998 Final revision received: 3 March 1999 Accepted: 26 March 1999 相似文献
986.
987.
Carcinoid tumor of the bile duct: Case report 总被引:1,自引:0,他引:1
N. Fujita M.D. F. Mochizuki S. Lee K. Satoh G. Kobayashi A. Yano T. Shimoda 《Abdominal imaging》1989,14(1):151-154
Carcinoid tumor of the bile duct is extremely rare. Ten cases have been reported in the literature. This report describes the eleventh case. A 55-year-old woman was hospitalized with biliary stenosis. Sonography (US) and computed tomography (CT) demonstrated a tumor in the upper common hepatic duct (CHD). Percutaneous transhepatic cholangiography showed extraluminal growth of the tumor. The tumor was resected and histologic examination showed carcinoid tumor of the common hepatic duct. 相似文献
988.
989.
Summary. The complete nucleotide sequences of the double-stranded RNA genome segments 5 (S5) from Bombyx mori cypovirus 1 (BmCPV-1) strains I and H were determined. The segments consisted of 2,852 nucleotides encoding putative proteins
of 881 amino acids with molecular masses of approximately 101 kDa (p101). A homology search showed that p101 has high similarity
(93%) to foot-and-mouth disease virus (FMDV) 2A protease (2Apro) at amino acid position 219 to 235. These findings suggest the possibility that p101 encoded by BmCPV-1 S5 might be cleaved
into two non-structural proteins by post-translational autocleavage involving a 2Apro-like protease.
Received February 21, 2000 Accepted June 23, 2000 相似文献
990.
Three new labdane diterpenoids, pacovatinins A-C (1-3), were isolated from seeds of the Brazilian medicinal plant Renealmia exaltata ("Pacová-catinga"), and their structures including absolute configurations were elucidated by spectroscopic data and a modified Mosher method. 相似文献