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951.
Akatsuka R Sasaki K Zahmaty MS Noji M Anada T Suzuki O Kuriyagawa T 《Journal of biomedical materials research. Part B, Applied biomaterials》2011,(2):210-216
This study aimed to create hydroxyapatite (HAp) film by powder jet deposition with manipulating the blasting nozzle above human enamel and to examine the microstructural and mechanical properties of the HAp film and the bonding strength at the interface between the HAp film and the enamel substrate. HAp particles calcinated at 1200°C with an average size of 4.7 μm were used. The HAp particles were mixed with carrier gas (N?) to form an aerosol flow and was accelerated and blasted from the nozzle onto the enamel substrate at room temperature and atmospheric pressure. To evaluate the microstructure, scanning electron microscope (SEM) images of the surface and cross section of the HAp films and a three-dimensional profile of the HAp films were observed. To evaluate the mechanical properties, the micro-Vickers hardness and the bonding strength of the HAp films to the enamel substrate were measured. The deposition area of the HAp film was over 3 × 4 mm. The average and maximum thickness were about 30 and 40 μm, respectively. No significant difference was observed between the hardness of the HAp film and the enamel (p > 0.05). The bonding strength of the HAp film was the same as the bonding strength between composite resin and enamel. Compared with previous reports, wider and thicker HAp film was created on the enamel substrate successfully. The HAp film, which has same hardness with enamel and same bonding strength to the enamel with composite resin, would be a candidate as dental restorative materials. 相似文献
952.
Koichi Aiura Masahiro Shinoda Ryo Nishiyama 《Journal of hepato-biliary-pancreatic sciences》2011,18(2):276-281
Background
Ampullary tumors have to be completely resected, but substantial morbidity and mortality rates are associated with pancreaticoduodenectomy (PD). Local resection can be the procedure of choice in selected ampullary lesions for high-risk patients.Methods
Preoperative examination indicated that the ampullary tumor extended into the common bile duct without evidence of pancreatic duct involvement and no definite invasion into either the duodenum or the pancreas. We performed a complete resection of the extrahepatic bile duct and the ampulla of Vater, including the tumor, without performing PD by dissecting the intrapancreatic bile duct from the pancreas both downward towards the ampulla of Vater and upward using a transduodenal approach.Results
The operation was successfully completed, and the postoperative course was uneventful, with the exception of a minor pancreatic fistula from retropancreatic dissection. The final pathological examination demonstrated well-differentiated tubular adenocarcinoma limited to the mucosa with negative surgical margins.Conclusion
Complete resection of the extrahepatic bile duct and the ampulla of Vater through a transduodenal approach can be a feasible and safe surgical procedure for selected ampullary tumors in high-risk patients. 相似文献953.
Yuma Yamada Ryo Furukawa Yukari Yasuzaki Hideyoshi Harashima 《Molecular therapy》2011,19(8):1449-1456
Mitochondrial dysfunction is associated with a variety of human diseases including inherited mitochondrial diseases, neurodegenerative disorders, diabetes mellitus, and cancer. Effective medical therapies for mitochondrial diseases will ultimately require an optimal drug delivery system, which will likely be achieved through innovations in the nanotechnology of intracellular trafficking. To achieve efficient mitochondrial drug delivery, two independent processes, i.e., “cytoplasmic delivery through the cell membrane” and “mitochondrial delivery through the mitochondrial membrane” are required. In previous studies, we developed an octaarginine (R8) modified nano carrier for efficient cytoplasmic delivery, showing that R8-modified liposomes were internalized into cells efficiently. On the other hand, we also constructed MITO-Porter for the mitochondrial delivery of macromolecules, a liposome-based carrier that delivers cargos to mitochondria via membrane fusion. Here, we report the development of a dual function MITO-Porter (DF-MITO-Porter), based on the concept of integrating both R8-modified liposomes and MITO-Porter. We show that the DF-MITO-Porter effectively delivers exogenous macro-biomolecules into the mitochondrial matrix, and provide a demonstration of its potential use in therapies aimed at mitochondrial DNA. 相似文献
954.
Taketani T Tamura H Takasaki A Lee L Kizuka F Tamura I Taniguchi K Maekawa R Asada H Shimamura K Reiter RJ Sugino N 《Journal of pineal research》2011,51(2):207-213
This study investigated whether melatonin protects luteinized granulosa cells from reactive oxygen species (ROS) as an antioxidant to enhance progesterone production in the follicle during ovulation. Follicular fluid was sampled at the time of oocyte retrieval in women undergoing in vitro fertilization and embryo transfer (IVF-ET). Melatonin concentrations in the follicular fluid were positively correlated with progesterone concentrations (r = 0.342, P < 0.05) and negatively correlated with the concentration of 8-hydroxy-2'-deoxyguanosine (8-OHdG), an oxidative stress marker (r = -0.342, P < 0.05). The progesterone and 8-OHdG concentrations were negatively correlated (r = -0.246, P < 0.05). Luteinized granulosa cells were obtained at the time of oocyte retrieval in women undergoing IVF-ET. Cells were incubated with H(2)O(2) (30, 50, 100 μm) in the presence or absence of melatonin (1, 10, 100 μg/mL). Progesterone production by luteinized granulosa cells was significantly inhibited by H(2)O(2). Melatonin treatment overcame the inhibitory effect of H(2) O(2) . Twenty-five patients who had luteal phase defect (serum progesterone concentrations <10 ng/mL during the mid-luteal phase) were divided into two groups during the next treatment cycle: 14 women were given melatonin (3 mg/day at 22:00 hr) throughout the luteal phase and 11 women were given no medication as a control. Melatonin treatment improved serum progesterone concentrations (>10 ng/mL during the mid-luteal phase) in nine of 14 women (64.3%), whereas only two of 11 women (18.1%) showed normal serum progesterone levels in the control group. In conclusion, melatonin protects granulosa cells undergoing luteinization from ROS in the follicle and contributes to luteinization for progesterone production during ovulation. 相似文献
955.
956.
Kobatake R Sato T Fujiwara Y Sunami H Yoshioka R Ikeda T Saito H Ujihira T 《Heart and vessels》2011,26(4):379-384
Although slow/no-reflow is a serious problem complicating primary percutaneous coronary interventions (PCI) for acute myocardial
infarction (AMI) and is associated with a poor prognosis, its efficacious treatment remains problematic. We compared the acute,
in-hospital and long-term (1 year) effects of nitroprusside (NTP) with those of nicorandil (NC) on the slow/no-reflow phenomenon.
Forty-nine of 442 consecutive patients with AMI who underwent primary PCI complicated by slow/no-reflow and who received intracoronary
NTP (n = 25) or NC (n = 24) administration were studied. Both NTP and NC induced significant improvements in coronary flow, with increases in TIMI
flow grade from 1.64 ± 0.62 to 2.74 ± 0.36 (p < 0.001) and 1.60 ± 0.86 to 2.23 ± 0.91 (p < 0.001), and in corrected TIMI frame count from 37.8 ± 15.1 to 13.7 ± 7.1 (p < 0.001) and 30.8 ± 20.7 to 19.3 ± 17.9 (p < 0.001), respectively. The degree of improvement in TIMI flow grade (post–pre/pre) and TIMI frame count (pre–post/pre) showed
that NTP was more effective than NC (NTP vs. NC: 0.88 ± 0.79, 0.37 ± 0.37, p = 0.008; 0.59 ± 0.23, 0.36 ± 0.27, p = 0.003, respectively). Congestive heart failure did not tend to last beyond 3 days after onset in the NTP group, which was
more than in the NC group, during hospitalization (1/25, 4/24, p = 0.143, respectively). At the 1-year follow-up, the NTP group tended to show more improvement than the NC group in MACE
(5/25, 9/24, p = 0.175, respectively). NTP is a more effective treatment for slow/no-reflow associated with PCI in patients with AMI and
may improve long-term clinical outcomes compared with NC. 相似文献
957.
Wakamatsu R Watanabe H Suzuki K Suga N Kitagawa W Miura N Nishikawa K Yokoi T Banno S Imai H 《Internal medicine (Tokyo, Japan)》2011,50(10):1109-1112
A 58-year-old Japanese woman presented with recurrent abdominal pain, chronic urticaria, and petechiae on her extremities, and hypocomplementemia, findings that were consistent with hypocomplementemic urticarial vasculitis syndrome (HUVS). A laboratory examination revealed that she had markedly elevated IgG levels (4,448 mg/dL; normal range, 870-1,700 mg/dL) with particularly high IgG4 levels (1,050 mg/dL; normal range, 48-105 mg/dL) and a high IgG4/total IgG ratio (0.22; normal range, 0.02-0.05). A skin biopsy demonstrated leukocytoclastic vasculitis with IgG4 deposition in the vascular lumen and vascular walls. A lymph node biopsy revealed reactive lymphoid hyperplasia with numerous IgG4-positive cells in the perifollicular area, but no sclerotic findings. A chromosomal analysis of an enlarged lymph node, without phytohemagglutinin (PHA) stimulation, demonstrated that one in every three analyzed cells had abnormalities, such as 44, XX, -13, add(15)(p11), -17, -17, and mar. 相似文献
958.
959.
The supply of transfusable red blood cells (RBCs) is not sufficient in many countries. If immortalized erythroid progenitor
cell lines able to produce transfusable RBCs in vitro were established, they would be valuable resources. However, such cell
lines have not been established. We have developed a robust method to establish immortalized erythroid progenitor cell lines
following the induction of hematopoietic differentiation of mouse embryonic stem (ES) cells and have established many immortalized
erythroid progenitor cell lines so far. Although their precise characteristics varied among cell lines, each of these lines
could differentiate in vitro into more mature erythroid cells, including enucleated RBCs. Following transplantation of these
erythroid cells into mice suffering from acute anemia, the cells proliferated transiently, subsequently differentiated into
functional RBCs, and significantly ameliorated the acute anemia. Considering the number of human ES cell lines that have been
established so far and the number of induced pluripotent stem cell lines that will be established in future, the intensive
testing of a number of these lines for establishing immortalized erythroid progenitor cell lines may allow the establishment
of such cell lines similar to the mouse erythroid progenitor cell lines. 相似文献
960.