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91.
We describe herein a case of inflammatory malignant fibrous histiocytoma (IMFH) of the gallbladder that subsequently metastasized to the ascending colon and later to the stomach. A 70-year-old Japanese man with a palpable mass in the right upper quadrant of the abdomen was referred to our hospital for investigation and treatment. Laboratory data showed severe leukocytosis and elevated serum granulocyte colony-stimulating factor (G-CSF) concentrations. A laparotomy was performed, and the tumor was excised en bloc with the gallbladder and part of the liver bed. Histopathologically, the tumor was composed of ordinary malignant fibrous histiocytoma (MFH) components characterized by pleomorphic tumor cells, bizarre giant cells, and conventional spindle cells in a storiform growth pattern, as well as a xanthogranulomatous component, including inflammatory cells, foamy histiocytes, and plasma cells. Immunohistochemical study revealed that the pleomorphic tumor cells and bizarre giant cells were positive for antibodies against α1-antitrypsin and α1-antichymotrypsin. The final pathologic diagnosis was IMFH. The tumor cells were diffusely positive for anti-G-CSF monoclonal antibody, and the inflammatory reaction subsided immediately after tumor resection, strongly suggesting that the primary tumor cells produced G-CSF. This patient is still alive with no signs of recurrence more than 3 years after his primary operation, which to our knowledge is the longest survival period ever reported. Therefore, visceral IMFH is manageable in some cases by resecting the primary and isolated metastatic lesions. Received: October 11, 2000 / Accepted: May 15, 2001  相似文献   
92.
PURPOSE: To elucidate the diurnal variation of human corneal curvature with regard to gender and menstrual cycle. METHODS: Changes in corneal curvature and intraocular pressure (IOP) were measured over 24 hours in 14 young adults using corneal topography and a non-contact tonometer. In study 1, seven males and seven females (after menses) were measured. In study 2, four females out of the seven volunteers who participated in study 1 were measured again during menses. RESULTS: The females after menses showed a remarkable diurnal variation throughout 24 hours. A significant difference between the light-wake periods and dark-sleep periods of 0.83 +/- 0.15 D was found (P < .01). Corneal curvature was significantly flatter during menses than after menses in the light-wake period (P < .05). In the males, no significant diurnal change (0.21 +/- 0.12 D) was measured in corneal curvature. CONCLUSIONS: Diurnal variation of corneal curvature was significant, approximately 0.83 D in young females after menses, and corneal curvature became flatter during menses in young females. Diurnal variation of corneal curvature is an important parameter for planning refractive surgery and contact lens wear.  相似文献   
93.
94.
Recently, it has been suggested that neural stem cells and neural progenitor cells exist in the ependyma that forms the central canal of the spinal cord. In this study, we produced various degrees of thoracic cord injury in adult rats using an NYU-weight-drop device, assessed the degree of recovery of lower limb motor function based on a locomotor rating scale, and analyzed the kinetics of ependymal cell proliferation and differentiation by proliferating cell nuclear antigen (PCNA), nestin, glial fibrillary acidic protein (GFAP), or GAP-43 immunostaining. The results showed that the time course of the ependymal cell proliferation and differentiation reactions differed according to the severity of injury, and that the responses occurred not only in the neighborhood of the injury but in the entire spinal cord. An increase in the locomotor rating score was related to an increase in the number of PCNA-positive cells, and the differentiation of ependymal cells into reactive astrocytes was involved in injury repair. No apoptotic cells in the ependyma were detectable by the TUNEL method. These results indicate that the ependymal cells of the spinal central canal are themselves multipotent, can divide and proliferate according to the severity of injury, and differentiate into reactive astrocytes within the ependyma without undergoing apoptosis or cell death.  相似文献   
95.
96.
Cardiac lymphangioma is uncommon and constitutes one of the rare forms of cardiac diseases. A 6-year-old girl had an abnormal electrocardiogram in a screening test on admission to an elementary school. Echocardiogram, computed tomogram, and magnetic resonance imaging showed a mediastinal multicystic mass that was adjacent to the left ventricle of the heart. The tumor was found to be originated in myocardium by left thoracotomy and pericadiotomy. A partial resection of tumor and a pericardial window were done. This case, to the authors' knowledge, represents the sixth reported case of cardiac lymphangioma. J Pediatr Surg 37:E32.  相似文献   
97.
BACKGROUND AND OBJECTIVES: We investigated the mechanism and characteristics of porcine myocardium tissue ablation in vitro with nanosecond 1,064- and 532-nm pulsed lasers at laser intensities up to approximately 5.0 GW/cm(2). Particular attention was paid to study the influence of the laser-induced plasma on the ablation characteristics. The applicability of these two lasers to transmyocardial laser revascularization (TMLR) was discussed. STUDY DESIGN/MATERIALS AND METHODS: Porcine myocardium tissue samples were irradiated with 1,064- and 532-nm, Q-switched Nd:YAG laser pulses, and the ablation depths were measured. The temporal profiles of the laser-induced optical emissions were measured with a biplanar phototube. For the ablated tissue samples, histological analysis was performed with an optical microscope and a polarization microscope. RESULTS: The ablation efficiency at 1,064 nm was higher than that at 532 nm. The ablation threshold at 1,064 nm (approximately 0.8 GW/cm(2)) was lower than that at 532 nm (approximately 1.6 GW/cm(2)), in spite of the lower absorption coefficient being expected at 1,064 nm. For the 1,064-nm laser-ablated tissues, thermal damage was very limited, while damage presumably caused by the mechanical effect was observed in most of the cases. For the 1,064-nm laser ablation, the ablation threshold was equal to the threshold of the laser-induced optical emission (approximately 0.8 GW/cm(2)), while for the 532-nm laser ablation, the optical emission threshold ( approximately 2.4 GW/cm(2)) was higher than the ablation threshold. CONCLUSIONS: We considered that for the 1,064-nm laser ablation, the tissue removal was achieved through a photodisruption process at laser intensities of > approximately 0.8 GW/cm(2). At laser intensities of > 3.0 GW/cm(2), however, the ablation efficiency decreased; this can be attributed to the absorption of incoming laser pulses by the plasma. For the 532-nm laser ablation, the tissue removal was achieved through a photothermal process at laser intensities of > approximately 1.6 GW/cm(2). At laser intensities of > 2.4 GW/cm(2), a photodisruption process may also contribute to the tissue removal, in addition to a photothermal process. With regard to the ablation rates, the 1,064-nm laser was more suitable for TMLR than the 532-nm laser. We concluded that the 1,064-nm Q-switched Nd:YAG laser would be a potential candidate for a laser source for TMLR because of possible fiber-based beam delivery, its compact structure, cost effectiveness, and easy maintenance. Animal trials, however, have to be carried out to evaluate the influence of the tissue damage.  相似文献   
98.
Japan's first commercial nuclear fuel cycling facilities, including a spent nuclear fuel reprocessing plant, are now under construction in Rokkasho, Aomori Prefecture (prefecture--an area of administration similar to a county in the U.S.). The reprocessing plant is due to be completed by 2004. We surveyed indoor and outdoor environmental gamma-ray dose rates throughout Aomori Prefecture from 1992 to 1996 to get background data before operation of the plant. Glass dosimeters were used to measure cumulative gamma-ray dose rate. The outdoor gamma-ray dose rates were measured at 109 locations in the prefecture. The indoor gamma-ray dose rates were measured at 81 locations, which were generally in a dwelling near the location of an outdoor measurement. The contribution of radionuclides in the ground to the outdoor dose rate was estimated by using in-situ gamma-ray spectrometry with a germanium detector. The spectra were measured at 20 locations used for the glass dosimeter measurements. The outdoor gamma-ray dose rate was higher in the Tsugaru area (western part of the prefecture) than in the Nanbu area (eastern part). Means of the dose rate were 28, 31, and 25 nGy h(-1) for the whole prefecture and Tsugaru and Nanbu areas, respectively. The dose rates in winter were lower than those in the other seasons due to the shielding effect of snow on the ground. Mean contributions of uranium series, thorium series and 40K to the dose rates were 7.7, 8.2, and 9.3 nGy h(-1), respectively. The indoor dose rate was generally higher than the outdoor one, and the mean ratio of indoor to outdoor dose rates was 1.42. Means of indoor gamma-ray dose rate were 41, 37, and 43 nGy h(-1) for the whole prefecture and Tsugaru and Nanbu areas, respectively. The average effective dose rate to people in the prefecture was estimated to be 0.24 mSv y(-1).  相似文献   
99.
PURPOSE: To translate the UCLA Prostate Cancer Index (UCLA PCI), which is designed to measure Quality of Life (QOL) of patients with prostate cancer, and to adapt it as needed for use in Japan. METHODS: We translated the original English version into a preliminary Japanese version in a multi-stage procedure according to established guidelines. Then, we tested the preliminary Japanese version on 6 patients with prostate cancer, and we revised the Japanese version based on the findings of the pilot test. RESULTS: The back-translation of the preliminary Japanese version was reviewed by its original developer, and some wordings were revised. In the pilot testing, the average time required to complete the questionnaire was 5.5 minutes. Four of the 20 items frequently had missing data (> 15%). This is believed to have been due to inappropriate wording of the response choices, which were revised accordingly. CONCLUSION: We conducted translation and cross-cultural adaptation of the Japanese version of UCLA PCI. Pilot testing proved to be useful in refining items and response choices.  相似文献   
100.
Surgically implanted ports have been used in continuous or repetitive intra-arterial (IA) chemotherapeutic infusions for patients with multiple liver metastases from colorectal cancer. Recently, a percutaneous implantation procedure was developed, facilitating safe and less invasive IA infusions in the treatment of various disease conditions. This article focuses on the interventional techniques for percutaneous implantation of a vascular access device, consisting of an indwelling catheter and an implantable port, to perform IA infusions. Additionally, we describe details of the alteration of blood flow by coil-embolization that can be performed to obtain selective drug distribution to the target area and to avoid side effects caused by the administration of the chemotherapeutic agent into nontarget areas.  相似文献   
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