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91.
A 56-year-old woman was referred to our hospital for airway compromise. Relapsing polychondritis was diagnosed by bronchial cartilage biopsy. Bronchoscopy showed tracheobronchial malacia due to the disappearance of bronchial cartilage as a result of chondritis. Stent insertion using a Dynamic stent (Rüsch; Kernen, Germany), Ultraflex stent (Boston Scientific International, Colombes, France) and TM stent (Fuji Systems Corp, Tokyo, Japan) was repeated for more than 7 years. Dramatic improvement of dyspnea was obtained each time. The patient survived during this period without oxygen inhalation or mechanical ventilation before she suddenly died due to suffocation caused by difficulty of sputum discharge.  相似文献   
92.
Arterial connection between the left and right kidneys is extremely rare. Only eight cases of such anomalous conditions have been reported in the world literature and all were confirmed by invasive angiography or dissection. We report a patient with this vascular anomaly clearly demonstrated by 16-slice multidetector computed tomography.  相似文献   
93.
Liver receptor homologue-1 (LRH-1) belongs to a class of nuclear orphan receptor. We examined immunolocalization of LRH-1 in 106 breast carcinomas. LRH-1 immunoreactivity was detected in 43% of the invasive ductal carcinoma. It was negatively correlated with clinical stage, histological grade and HER2 status, and positively associated with sex-steroid receptors, steroidogenic acute regulatory protein, P450 side-chain cleavage, and 3beta-hydroxysteroid dehydrogenase. LRH-1 immunoreactivity was also detected in 28% of the ductal carcinoma in situ. These results suggest that LRH-1 is frequently detected in breast carcinoma tissues, and plays important roles including the regulation of in situ steroidogenesis.  相似文献   
94.
Optical coherence tomography (OCT) is an evolving imaging modality that combines interferometry with low-coherence light to produce high-resolution tissue imaging. Cross-sectional in vivo images were obtained using an OCT device consisting of a Michelson interferometer, 1.3-microm broadband light source, and a handheld fiberoptic imaging probe. Image pixel resolution approached 10 microm. The mucosa of the oral cavity and oropharynx were examined in 41 patients during operative endoscopy. Optical coherence tomographic imaging was combined with endoscopic photography for gross and histologic image correlation. Optical coherence tomographic images of the oral cavity and oropharynx provided microanatomical information on the epithelium, basement membrane (BM), and supporting lamina propria (LP) of the mucosa. Normal microstructures identified in these tissues included an overlying keratin layer, papillae, ducts, glands, and blood vessels. Regions of pathologic features studied included mature scar, granulation tissue, mucous cysts, leukoplakia, and invasive cancer. Optical coherence tomographic imaging showed distinct zones of normal, altered, and ablated tissue microstructures for each pathologic process studied. Abnormal findings were directly compared with regions of normal tissue or conventional histopathologic features when tissue for analysis was available. This study provides a composite series of in vivo OCT images of the oral cavity and oropharynx in a variety of normal regions and pathologic states as well as outline future applications of OCT technology.  相似文献   
95.
BACKGROUND: Optical coherence tomography (OCT) is an emerging imaging modality that uses light to produce in vivo high-resolution cross-sectional images (7 microm) of tissues to depths of up to 3 mm. OCT is analogous to ultrasound, but relies on interferometry and low-coherence optical sources to produce images of tissue structure at the histological level. METHODS: In this study, OCT was used to image the mucosa overlying structures in the nasal cavity to obtain information regarding normative in vivo tissue microstructure. An OCT system using a Michaelson interferometer and a 1.3-microm broadband light source was incorporated into a fiber-optic imaging device that was inserted into the nasal cavity. Cross-sectional tomographic images of the anterior and posterior nasal septum, turbinates, and vestibule were acquired in 44 patients in either the office or the operating room during surgical endoscopy. RESULTS: OCT images of the nasal mucosa identified the distinct boundaries between the epithelium, lamina propria, and underlying bone/cartilaginous tissue. Within the lamina propria, features consistent with glands, ducts, and blood vessels were clearly identified. In patients who underwent decongestant therapy, before and after images showed distinct morphological changes in the mucosa. The thickness of the epithelium was tabulated, as well. CONCLUSION: This study establishes the potential of using OCT to produce high-resolution images of the nasal mucosa. As an in vivo tissue microstructural imaging modality, OCT may be valuable in studying the impact of allergic and infectious disease on the nasal mucosa and monitoring its response to pharmacologic therapy.  相似文献   
96.
OBJECTIVES: Optical coherence tomography (OCT) is a high-resolution optical imaging technique that produces cross-sectional images of living tissues using light in a manner similar to ultrasound. This prospective study evaluated the ability of OCT to identify the characteristics of laryngeal cancer and measure changes in the basement membrane, tissue microstructure, and the transition zone at the edge of tumors. MATERIALS AND METHODS: One hundred thirty-three patients underwent OCT examination during surgical endoscopy of the head and neck. Twenty-two patients with laryngeal cancer or a history of laryngeal cancer were imaged with a fiberoptic OCT system. Tumor and adjacent transition zones were imaged along with uninvolved subsites. OCT images were correlated with histopathology. RESULTS: Twenty-six OCT examinations were performed in 22 patients. Basement membrane disruption was seen in 18 subjects, all of whom had histology showing classic features of cancer. A transition zone to uninvolved epithelium at the tumor periphery was also often observed. In six studies, benign or premalignant processes were histologically confirmed. In three thin, superficial lesions, an intact basement membrane was observed. The basement membrane could not be identified in three other bulky exophytic, premalignant lesions, primarily because of increased superficial signal backscattering observed in pathologic tissues. CONCLUSIONS: OCT clearly identifies basement membrane violation from laryngeal cancer and can identify transition zones at the cancer margin. In bulky exophytic lesions, OCT signal may not penetrate deeply enough to show the basement membrane, but for many suspicious lesions that require exclusion of cancer, OCT shows potential for assisting in diagnostic assessment.  相似文献   
97.
PURPOSE: To report a man with markedly increased intraocular pressure in a unilateral exfoliated eye during hemodialysis. METHOD: Case report. RESULTS: A 75-year-old man with unilateral exfoliative glaucoma complained of blurred vision in his right eye during hemodialysis. The blurred vision always occurred during hemodialysis, and the intraocular pressure was increased during hemodialysis. The average increase in intraocular pressure during hemodialysis in the right eye was 22.5 mm Hg, and the intraocular pressure in the left eye remained in the normal range during hemodialysis. Argon laser trabeculoplasty was performed on the right eye, and a decrease in intraocular pressure was attained. CONCLUSION: Physicians must be alert to intraocular pressure increases in these eyes during hemodialysis.  相似文献   
98.
99.
BACKGROUND: Recent laboratory studies have suggested that cadmium is an estrogenic compound and may be a potential risk factor for breast cancer. METHODS: We investigated the relationship between urinary cadmium concentrations and serum concentrations of estrone, testosterone, and dehydroepiandrosterone sulfate in 164 postmenopausal Japanese women. RESULTS: There was a significant positive association between the urinary cadmium and serum testosterone levels after controlling for age and body mass index. The mean testosterone level was 28% higher in women with high urinary cadmium (> or = 3.00 microg/g creatinine) than in those with low urinary cadmium (< 2.00 microg/g creatinine). Urinary cadmium was not significantly associated with serum estrone and dehydroepiandrosterone sulfate levels. Additional adjustment for smoking, alcohol and reproductive factors including known risk factors for breast cancer did not substantially alter the results. CONCLUSION: Data suggested that cadmium exposure is associated with increased testosterone levels. As high testosterone levels have been associated with the risk of breast cancer, the involvement of cadmium exposure in breast cancer risk should be evaluated in future studies.  相似文献   
100.
The effects of i.c.v. administration of orexin/hypocretin on plasma ACTH, corticosterone and c-fos mRNA in the paraventricular nucleus (PVN) of the rat were examined. Plasma ACTH levels were markedly increased at 30 min after i.c.v. administration of orexin-A. Plasma corticosterone levels were significantly increased in a dose-related manner 30 min after i.c.v. administration of orexin-A and orexin-B. In situ hybridization histochemistry revealed that the induction of the c-fos mRNA in the parvocellular division of the PVN was increased in a dose-related manner 30 min after i.c.v. administration of orexin-A and orexin-B. These results suggest that central orexin/hypocretin activates hypothalamo-pituitary-adrenal (HPA) axis and may be involved in stress-induced activation of the HPA axis.  相似文献   
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