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91.
Summary Immunoelectron microscopic localization of the nervous system specific protein S-100 in the cultured rat glioma cells was successfully conducted by an unique immunocytochemical technique using peroxidase-labeled antigen binding Fab' fragments.The intensely electron dense reaction product for S-100 protein was localized mainly at ribosome granules associated with endoplasmic reticulum membranes and at free ribosome granules. S-100 protein was also associated to some extent with the cytoplasmic and nuclear membranes. A positive reaction was localized at the nuclear pores as if it were being prevented from entering into the nucleus. No activity was found in the nucleoplasm except for a slightly positive reaction product associated with nucleolus. The possible role for S-100 protein in neural cells was discussed in relation to the nuclear acidic proteins involved in genomic regulation. 相似文献
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BACKGROUND AND OBJECTIVES: To investigate whether endogenous opioids might be involved in the mechanisms that underlie hemorrhagic shock-induced analgesia, formalin tests were performed after hemorrhage and reinfusion in naloxone pretreated and untreated rats. METHODS: Twenty-four adult male Sprague-Dawley rats were divided into control (n = 6), saline (n = 6), naloxone 10 mg/kg (n = 6), and naloxone 100 mg/kg (n = 6) groups. The mean blood pressure (mBP) was kept at 50 to 60 mm Hg for 30 minutes by draining arterial blood in the saline group and the naloxone groups. After 15 minutes of returning mBP to normal levels by reinfusion of the drained shed blood, 10% formalin (3.7% formaldehyde solution, 0.1 mL) was injected into the left rear paw. Nociceptive behaviors were observed for 1 hour after the formalin injection. RESULTS: Nociceptive behaviors of the posthemorrhagic shock groups were significantly lower than those of the control group. No significant difference was seen in nociceptive behaviors among the saline and naloxone groups. CONCLUSION: Naloxone did not reverse the hemorrhagic shock-induced analgesia, which suggests that endogenous opioids might not be a major factor that governs stress-induced analgesia (SIA) after hemorrhagic shock. 相似文献
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Matsuura H Inoue T Ogasawara K Sasaki M Konno H Kuzu Y Nishimoto H Ogawa A 《Neurologia medico-chirurgica》2005,45(8):395-8; discussion 398-9
Magnetic resonance (MR) imaging is an important diagnostic tool for neurosurgical diseases but susceptibility artifacts caused by biomaterial instrumentation frequently causes difficulty in visualizing postoperative changes. The susceptibility artifacts caused by neurosurgical biomaterials were compared quantitatively by 0.5, 1.5, and 3.0 Tesla MR imaging. MR imaging of uniform size and shape of pieces ceramic (zirconia), pure titanium, titanium alloy, and cobalt-based alloy was performed at 0.5, 1.5, and 3.0 Tesla. A linear region of interest was defined across the center of the biomaterial in the transverse direction, and the susceptibility artifact diameter was calculated. Susceptibility artifacts developed around all biomaterials at all magnetic field strengths. The artifact diameters caused by pure titanium, titanium alloy, and cobalt-based alloy increased in the order of 0.5, 1.5, to 3.0 Tesla magnetic fields. The artifact diameter of ceramic was not influenced by magnetic field strength, and was the smallest of all biomaterials at all magnetic field strengths. The artifacts caused by biomaterials except ceramic increase with the magnetic field strength. Ceramic instrumentation will minimize artifacts in all magnetic fields. 相似文献
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Masumoto K Nishimoto Y Taguchi T Tsutsumi Y Kanemitsu S Hara T Suita S 《Pediatric nephrology (Berlin, Germany)》2005,20(10):1496-1499
Shiga toxin-producing Escherichia coli (E. coli) is known to be one of the main causes of hemolytic uremic syndrome (HUS). Of the secondary complications of HUS, colonic stricture is relatively rare. We herein report on a Japanese girl that demonstrated sigmoid colon stricture secondary to HUS caused by an infection of E. coli O-157. Severe HUS occurred after the E. coli O-157 infection, so hemodialysis was performed due to renal failure. However, 1 month after recovery from HUS, abdominal symptoms occurred. A contrast study in the colon revealed a sigmoid colon stricture. The stricture was operatively resected. Thereafter, her postoperative course was uneventful. We also review the occurrence of this complication secondary to HUS in the literature. 相似文献
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A case of sebaceous epithelioma on the scalp of a 50 year old female was reported. Using an electron microscope, cells from the tumor were classified into 5 stages according to their development. Furtheremore, our investigation indicate that lipid synthesis was activated in sebaceous epithelioma cells rather than in normal sebaceous cells, and can apparently be distinguished from lipid-droplet formation by degradation. These sebaceous epithelioma cells also possessed the ability to secrete which suggests that these tumor cells originated from germinative cells of the sebaceous gland rather than epidermal basal cells. 相似文献
100.
Yamada M Chiba T Sasabe J Nawa M Tajima H Niikura T Terashita K Aiso S Kita Y Matsuoka M Nishimoto I 《Behavioural brain research》2005,164(2):139-146
Amyloid beta (Abeta) is closely related to the onset of Alzheimer's disease (AD). To construct AD animal models, a bolus administration of a large dose of toxic Abeta into the cerebral ventricles of rodents has been performed in earlier studies. In parallel, a continuous infusion system via an osmotic pump into the cerebral ventricle has been developed to make a rat AD model. In this study, we developed a mouse AD model by repetitive administration of Abeta25-35 via a cannula implanted into the cerebral ventricle. Using this administration system, we reproducibly constructed a mouse with impaired spatial working memory. In accordance with the occurrence of the abnormal mouse behavior, we found that the number of choline acetyltransferase (ChAT)-positive neurons was reduced in paraventricular regions of brains of Abeta25-35-administered mice in a dose-dependent manner. Considering that the repetitive administration of a small dose of toxic Abeta via an implanted cannula leads to a brain status more resembling that of the AD patients than a bolus injection of a large dose of Abeta, and therapeutic as well as toxic agents are able to be repeatedly and reliably administered via an implanted cannula, we concluded that the implanted cannula-bearing AD mouse model is useful for development of new AD therapy. 相似文献