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排序方式: 共有980条查询结果,搜索用时 281 毫秒
881.
Hagiwara A Fukazawa Y Deguchi-Tawarada M Ohtsuka T Shigemoto R 《The Journal of comparative neurology》2005,489(2):195-216
Synaptic vesicle release occurs at a specialized membrane domain known as the presynaptic active zone (AZ). Several membrane proteins are involved in the vesicle release processes such as docking, priming, and exocytotic fusion. Cytomatrix at the active zone (CAZ) proteins are structural components of the AZ and are highly concentrated in it. Localization of other release-related proteins including target soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (t-SNARE) proteins, however, has not been well demonstrated in the AZ. Here, we used sodium dodecyl sulfate-digested freeze-fracture replica labeling (SDS-FRL) to analyze quantitatively the distribution of CAZ and t-SNARE proteins in the hippocampal CA3 area. The AZ in replicated membrane was identified by immunolabeling for CAZ proteins (CAZ-associated structural protein [CAST] and Bassoon). Clusters of immunogold particles for these proteins were found on the P-face of presynaptic terminals of the mossy fiber and associational/commissural (A/C) fiber. Co-labeling with CAST revealed distribution of the t-SNARE proteins syntaxin and synaptosomal-associated protein of 25 kDa (SNAP-25) in the AZ as well as in the extrasynaptic membrane surrounding the AZ (SZ). Quantitative analysis demonstrated that the density of immunoparticles for CAST in the AZ was more than 100 times higher than in the SZ, whereas that for syntaxin and SNAP-25 was not significantly different between the AZ and SZ in both the A/C and mossy fiber terminals. These results support the involvement of the t-SNARE proteins in exocytotic fusion in the AZ and the role of CAST in specialization of the membrane domain for the AZ. 相似文献
882.
Tsujita Y Yanagawa Y Takasu A Takemoto MA Sakamoto T Okada Y Katoh H 《No shinkei geka. Neurological surgery》2005,33(11):1083-1088
A 50-year-old female who had a past history of non-treated hypertension, demonstrated a coma on arrival. CT revealed a high density lesion measuring 23 mm in transverse diameter and 15 mm in height at the ventral mid pons without breaking into a fourth ventricle or extending to the midbrain. She required mechanical ventilation support. Her consciousness improved on the 2nd hospital day. She showed tetra-plegia, which was especially dominant on her right side. Her symptoms gradually improved until she could stand and she was eventually discharged on the 41st hospital day. At 90 days after the initial presentation, an enhanced head MRI showed the absorption of the hematoma and no existence of any vascular malformation was observed. We herein report a case who dramatically recovered from a hypertensive pontine hemorrhage, despite the fact that she demonstrated several risk factors for a poor prognosis. The fact that the size of the hematoma was not so huge, and the location of the hematoma spared both the ascending reticular activating system and the nuclei, may explain the favorable outcome in this case. 相似文献
883.
A prospective study of the prevalence of gastroesophageal reflux disease and confounding factors 总被引:3,自引:0,他引:3
Shimazu T Matsui T Furukawa K Oshige K Mitsuyasu T Kiyomizu A Ueki T Yao T 《Journal of gastroenterology》2005,40(9):866-872
Background The prevalence of gastroesophageal reflux disease (GERD) has reportedly risen in recent years. Difficulties associated with
endoscopic diagnosis mean it is not easy to determine its precise prevalence. A prospective study of the prevalence of endoscopy-positive
GERD (EP-GERD) was conducted at Higuchi Hospital, a general hospital in Northwestern Kyushu, Japan. The study also correlated
factors that might affect prevalence (age, sex, and functions of the gastroesophageal junction).
Methods From consecutive patients undergoing endoscopic examination at Higuchi Hospital between January 2000 and April 2003, 1234
patients without severe complications were examined for the possible presence of GERD. Patients were stratified by age and
sex, and the prevalence in each group ascertained. EP-GERD was defined on the four-level scale of the Los Angeles classification.
Endoscopic classification of gastroesophageal flap valve ([GEFV] functional anomalie; using a four-level scale), was done
as proposed by Hill et al. in 1996, to assess flap-valve morphology. Six items were evaluated: (1) symptoms and primary diseases;
(2) prevalence of development of EP-GERD classified by age and sex; (3) endoscopic morphology of the GEFV as an expression
of the functions of the gastroesophageal junction, and its prevalence by age and sex; (4) regression analysis and Spearman's
rank correlation of GEFV and EP-GERD grades; (5) prevalence of EP-GERD and GEFV stratified by age and analyzed; and (6) multiple
regression analysis of EP-GERD and explanatory variables (age, sex, and GEFV).
Results The overall prevalence of EP-GERD was 5.8% (72/1234) and this patient group was dominated by men. Aging had minimal effect
on prevalence in men, but the prevalence rose among women as they aged. The age-stratified prevalence of GEFV functional anomalies
was similar to the age-stratified prevalence of EP-GERD in both sexes. The correlation between EP-GERD and GEFV functional
anomalies was high regardless of sex.
Conclusions We postulate that the mechanisms leading to the development of GEFV functional anomalies in men are different from those in
women. Future evaluations of EP-GERD should also observe GEFV function. 相似文献
884.
Anzai T Yoshikawa T Takahashi T Maekawa Y Okabe T Asakura Y Satoh T Mitamura H Ogawa S 《Cardiology》2003,99(1):47-53
BACKGROUND: We have reported that a marked elevation in serum C-reactive protein (CRP) level is a predictor for infarct expansion and cardiac rupture after AMI. Although beta-blockers prevent cardiac rupture after AMI, their effect on serum CRP elevation has not been determined. METHODS: We studied a total of 154 patients with first Q-wave AMI. Patients complicated by pump failure were excluded from this study. Eighty-two patients received beta-blocker treatment within 24 h of the onset of AMI, while 72 patients received no beta-blocker treatment. Peak serum creatine kinase (CK) and CRP levels were determined by serial measurements. RESULTS: There was no difference between the groups according to age, sex, coronary risk factors, pre-infarction angina, infarct site, prior use of cardiovascular drugs, use of revascularization therapy, and prevalence of multivessel disease. Beta-blocker treatment was associated with a lower peak CRP level (6.9 +/- 6.1 vs.10.8 +/- 9.3 mg/dl, p = 0.002), a shorter duration from the onset to the peak CRP level (2 +/- 1 vs. 3 +/- 2 days, p < 0.0001), a lower incidence of cardiac rupture (p = 0.03) and lower in-hospital cardiac mortality (p = 0.02), despite similar peak CK levels. CONCLUSION: The early use of beta-blockers is associated with decreased serum CRP level and a favorable clinical outcome after first Q-wave AMI, suggesting some beneficial effects of beta-blockers on infarct healing after AMI. 相似文献
885.
886.
Yanagawa Y Kiyozumi T Hatanaka K Itoh T Sakamoto T Okada Y 《American journal of ophthalmology》2004,137(4):775-777
PURPOSE: To report a case of reversible blindness associated with severe alcoholic ketoacidosis. DESIGN: Observational case report. METHODS: A 44-year-old male presented with gradual bilateral blindness that developed within a 24-hour period. He suffered from ethanol-induced severe ketoacidosis and shock and was resuscitated with epinephrine and sodium bicarbonate. RESULTS: The treatment of acidosis led to a rapid resolution of the patient's blindness. CONCLUSIONS: It is important to understand the role of severe acidosis as the sole causative factor of reversible bilateral blindness. 相似文献
887.
Oshige M Kuramochi K Ohta K Ogawa A Kuriyama H Sugawara F Kobayashi S Sakaguchi K 《Journal of medicinal chemistry》2004,47(20):4971-4974
The triterpenoid structure is a promising motif for the molecular design of DNA polymerase inhibitors.(1) In this study, 2-(cholesteryloxy)acetic acid (3), 2-(cholestanyl)acetic acid (7), and 2-(stigmasteryl)acetic acid (11) were found to selectively affect only DNA polymerase alpha (pol.alpha). The presence of a carboxyl group at position 28 appears to be essential for the inhibition of the pol.alpha activity. With pol.alpha, these compounds acted by competing with the template-primer DNA and noncompetitively with the substrate. 相似文献
888.
Human ATP-binding cassette transporter ABCC10: expression profile and p53-dependent upregulation 总被引:1,自引:0,他引:1
Takayanagi S Kataoka T Ohara O Oishi M Kuo MT Ishikawa T 《Journal of experimental therapeutics & oncology》2004,4(3):239-246
Human ATP-binding cassette (ABC) transporter genes are classified into seven sub-families, where "C" subfamily comprises a total of 13 gene members. The ABCC10 cDNA was cloned in the human full-length cDNA project at the Kazusa DNA Research Institute. However, current information is limited regarding its physiological function and gene expression. In the present study, we have investigated the expression of the ABCC10 gene to gain insight into its biological nature. By quantitative PCR, ABCC10 gene expression is demonstrated to be highest in pancreas among the adult and fetal tissues and tumors presently tested. Decreased expression was observed when resting T- and B-cells were activated. Furthermore, when we examined its expression under apoptotic conditions, we found that ABCC10 mRNA levels remarkably increased in doxorubicin-treated MCF7 cells, whereas its up-regulation was suppressed in p53-dominant-negative MCF7 cells. These results suggest that expression of the ABCC10 gene is regulated in a p53-dependent manner during DNA-damage-related apoptosis. 相似文献
889.
Evidence is accumulating to strongly suggest that drug transporters are one of the determining factors governing the pharmacokinetic profile of drugs. To date, a variety of drug transporters have been cloned and classified as solute carriers and ATP-binding cassette transporters. Such drug transporters are expressed in various tissues such as the intestine, brain, liver, and kidney, and play critical roles in the absorption, distribution and excretion of drugs. However, at the present time, information is limited regarding the genetic polymorphism of drug transporters and its impact on their function. In this context, we have undertaken the functional analyses of the polymorphisms identified in drug transporter genes. This article aims to provide an overview on the functional aspects of the non-synonymous polymorphisms of drug transporters and to present standard methods for the evaluation of the effect of polymorphisms on their function. 相似文献
890.
Osteosarcomas after the Age of 50: A Clinicopathologic Study of 64 Cases—an Experience in Northern Japan 总被引:3,自引:0,他引:3
Okada K Hasegawa T Nishida J Ogose A Tajino T Osanai T Yanagisawa M Hatori M 《Annals of surgical oncology》2004,11(11):998-1004
Background: The clinicopathologic profile and prognostic factors of osteosarcomas after the age of 50 years have been obscure.Methods: Clinicopathologic features were analyzed in 645 patients with osteosarcoma who were registered at the Tohoku Musculoskeletal Tumor Society and National Cancer Center in Tokyo between 1972 and 2002.Results: Sixty-four patients (9.9%; 34 men and 30 women) were more than 50 years old. The most common location was the distal femur (n = 13), followed by the pelvis (n = 10), proximal femur (n = 9), and proximal fibula (n = 6). Seven (11%) patients had lung metastasis at initial presentation. On radiographs, an osteolytic appearance without periosteal reactions was a common and characteristic feature. Forty-eight tumors (75%) were classified as conventional osteosarcomas. Fourteen cases (22%) were secondary; postradiation osteosarcoma was most common in these patients, but there was no Pagets sarcoma. At the initial presentation, misdiagnoses without biopsy were made in 15 (23%) of the 64 cases. Preoperative chemotherapy was given to 22 patients, but the effect was poor in 18 cases (82%). Fifty-four patients underwent surgery, whereas the other 10 patients were treated without surgery because of systemic or inoperable local conditions. The overall survival rate at 5 years was 55.5%. Multivariate analysis showed initial pulmonary metastasis, axial tumor location, and larger tumors as significant prognostic factors.Conclusions: In northern Japan, most patients with osteosarcoma after the age of 50 had primary osteosarcoma. Careful radiological examination and biopsy are mandatory for correct diagnosis. Current systemic chemotherapy is not effective for this age group. Alternative treatment strategies should be considered. 相似文献