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991.
Management of juvenile angiofibromata 总被引:3,自引:0,他引:3
J G Spector 《The Laryngoscope》1988,98(9):1016-1026
Twenty-eight angiofibromata, treated between 1971 and 1988, were reviewed according to their patterns of invasion, blood supply, treatment modality, and clinical course. All patients were males, and two patients were black. The average age was 14.8 years. Nasopharyngeal masses, epistaxis, and facial asymmetry were the most common presenting symptoms. Tumors extended along predetermined pathways following the vascularity of the external carotid system. CNS extension arose via the superior orbital fissure or direct extension from the sphenoid sinus. Angiography described the neoplastic vascularity, CT with contrast demonstrated tumor location and extracranial extension, and MRI best demonstrated CNS invasion. All lesions were reclassified according to the American Joint Committee staging system. Twenty-seven patients were operated upon; four with cryotherapy and 23 following embolization. Two tumors recurred and needed additional surgery. One patient with CNS invasion was treated with estrogen and radiotherapy for cure. Tumor staging is not particularly helpful in decision making, because surgery must be individualized according to tumor location and extent. Surgical approaches for specific tumor locations are discussed. 相似文献
992.
Two hundred thirty-one sequential parotid masses seen from January 1982 to July 1986 were reviewed for their clinical presentation, diagnostic evaluation, pathologic findings, and therapeutic approach. The results were compared with the previously reported findings on parotid masses. There were 146 (63.2%) benign tumors, 60 (21.6%) malignancies, and 35 (15.2%) nonmalignant lesions. Tumors were classified according to their histopathologic diagnosis. An asymptomatic mass was the most common presentation. Radiological evaluation was mainly with computed tomography. The primary surgical procedure was parotidectomy with facial nerve preservation. A selected group of patients was referred for radiation therapy. Our study demonstrated that non-neoplastic lesions contribute a significant number of masses in the differential diagnosis of parotid tumors. Metastatic squamous cell carcinoma was the most frequently encountered malignancy. Deep lobe tumors were twice as common as previously reported. 相似文献
993.
994.
The speculation whether juvenile laryngeal papillomatosis may transform into or be associated with epidermoid carcinoma is explored. We document a case of invasive laryngeal carcinoma arising in preexisting juvenile laryngeal papillomatosis. After multiple childhood laryngoscopies and a tracheotomy, a 54-year-old, 30-pack per year smoker, who had never received radiation therapy, developed a florid exophytic transglottic squamous cell carcinoma. Histologically, the invasive epidermoid carcinoma was surrounded by a field of papillomata with varying degrees of atypical changes. After total laryngectomy, isolated papillomata were found in the lower trachea. There were no cervical lymph node metastases. No postoperative radiation therapy was given. Persistent squamous papillomata in the tracheostomy site, the lower trachea, and the posterior pharynx were treated with the CO2 laser. We emphasize the need to maintain a high index of suspicion for malignancy. In addition, we review the problem of benign papillomata in the aerodigestive tract following laryngectomy. 相似文献
995.
The surface or solvent accessibility of certain individual aromatic residues of calf-gamma II crystallin in solution (1 mM) were measured by the dramatic intensity enhancements of NMR lines generated by the interactions of cyclic radical pair formation of the 3-N-carboxymethyl lumiflavin (flavin I) dye excited (488nm) by an argon laser (5 watts) with the protein. This effect is called photo-chemically induced dynamic nuclear polarization: photo-CIDNP. The "light" and "dark" NMR spectra were taken in alternating scans in the pulsed Fourier transform mode on a Bruker 360 MHz instrument. Subtraction results in the photo-CIDNP difference spectrum containing lines of the polarized residues. With flavin dyes only tyrosine, histidine, and tryptophan can be polarized. The respective theoretical static accessibility of these residues based upon van der Waal's contact radii have been calculated from the atomic coordinates and provide a basis for evaluating the dynamic NMR photo-CIDNP results and for assigning the resonances. These results suggest that while the four tryptophan residues are completely buried, His-113 and His-14 of the five histidines; and Tyr-165 and Tyr-62 of the fifteen tyrosines are sufficiently exposed to elicit a photo-CIDNP effect. These results confirm and extend the observations previously obtained with theoretical electrostatic programs and FT-NMR measurements. 相似文献
996.
997.
Leucocyte suspensions from some cases of acute myelogenous leukaemia produced large numbers of macrophages when cultured in vitro. The macrophages increased steadily in number during the first 1-2 wk of culture. The increase was partly derived from division of the macrophages themselves, partly from augmentation from supernatant cells not adherent to the surface of the culture flask. This augmentation occurred mostly in the first 24 hr of culture. The leukaemic macrophages had many features of normal macrophages as regards light microscopy, surface receptors, phagocytic activity and cytochemistry. Under the electron microscope, however, they had many abnormal characteristics, all of which have been recorded previously as features of malignant transformation. Cultures containing the abnormal macrophages and their precursor cells caused local solid tumours when injected into immune-deprived mice. The tumours were composed of rather uniform cells many of which resembled neoplastic reticulum cells. It is concluded that human leukaemic monocytes or promonocytes can develop into macrophages with ultrastructural features of malignancy. This appears to be the first demonstration of the development of neoplastic macrophages. It is suggested that some lymph node tumours of man may be composed of similar neoplastic macrophages and their precursor cells. 相似文献
998.
999.
Maternal smoking during pregnancy and conduct problems in high-risk youth: a developmental framework
Smoking during pregnancy is associated with adverse consequences for children. Most recently, it has been established as a risk factor for developmental psychopathology, specifically Conduct Disorder (CD). Although this association has been shown to be robust, developmental pathways from exposure to CD have not been established. We examined how prenatal exposure to cigarettes interacts with child and family factors to increase risk of CD symptoms in a longitudinal study of 10-year-old urban, African-American youth (N = 77). The effects of prenatal exposure at school age were moderated by child sex. Boys whose mothers smoked during pregnancy were significantly more likely to develop CD symptoms, but exposure did not increase risk in girls. A similar trend was found during infancy: prenatal smoking was associated with low sociability/negative emotionality only for boys. The effects of smoking during pregnancy were also moderated by the quality of the early caregiving environment. Exposed boys whose mothers were unresponsive during infancy were at increased risk of CD symptoms, but exposed boys with early responsive mothers were not. Prospective studies, with developmentally based measures of behavior across time, are critical for further elucidating pathways from prenatal exposure to cigarettes to the development of clinical disorder. The identification of a potentially modifiable, prenatal risk factor for early onset developmental psychopathology has important implications for prevention. 相似文献
1000.
V Cuneyt Kalfa Sheldon L Spector Tomas Ganz Alexander M Cole 《Annals of allergy, asthma & immunology》2004,93(3):288-292
BACKGROUND: The association of perennial allergic rhinitis (PAR) with recurrent sinusitis (RS) is well recognized. Anatomic abnormalities at the osteomeatal complex or ciliary dysfunction may play a significant role in some patients. However, for most patients with allergy, the determinants of RS are unknown. OBJECTIVE: To determine whether altered concentrations of antimicrobial peptides and proteins, such as lysozyme, lactoferrin, human beta-defensin-2 (HBD-2), and human neutrophil peptides 1 to 3 (HNP-1 to 3), contribute to the development of RS in patients with PAR. METHODS: Nasal secretions were collected by vacuum aspiration from 15 individuals with PAR+RS, 16 with PAR alone, and 16 controls. Lysozyme and lactoferrin levels were determined in nasal secretions by using quantitative enzyme-linked immunosorbent assay, and HBD-2 and HNP-1 to 3 levels were determined in nasal secretions by using semiquantitative Western blot analysis. Eosinophil-derived neurotoxin (EDN) levels were measured by using enzyme-linked immunosorbent assay as a marker of nasal eosinophilia in all 3 groups. RESULTS: Levels of EDN were elevated significantly in patients with PAR+RS compared with controls. Lysozyme levels were decreased significantly in patients with PAR+RS compared with PAR alone or controls. Mean lysozyme levels were significantly lower in patients with EDN levels greater than 1,000 ng/mL vs those with levels of 1,000 ng/mL or less in the PAR+RS group. There were no statistically significant differences in lactoferrin, HBD-2, and HNP-1 to 3 levels among the 3 groups. CONCLUSIONS: The presence of eosinophils and their products and reduced lysozyme concentrations may be critical factors that predispose the airways of patients with PAR to RS. 相似文献