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21.
In total, 269 methicillin-resistant Staphylococcus aureus (MRSA) and 434 methicillin-susceptible S. aureus (MSSA) isolates were investigated to determine their macrolide-lincosamide-streptogramin B (MLS(B)) resistance phenotypes and genotypes. The constitutive phenotype (61.3% in MRSA, 1.3% in MSSA) and erm(A) gene predominated among the 261 erythromycin-resistant MRSA isolates, while the inducible phenotype (38.7% in MRSA, 94.0% in MSSA) and erm(C) gene were more prevalent among the 150 erythromycin-resistant MSSA isolates. There was a higher incidence of the MLS(B) inducible phenotype compared with other countries, perhaps because MLS(B) antibiotics are not recommended as first-line agents against S. aureus in Japan.  相似文献   
22.
Neuropathological findings in two siblings with familial erythrophagocytic lymphohistiocytosis (FEL) are reported. Case 1 showed the typical neuropathological findings of FEL with lymphohistiocytic infiltration of the leptomeninges and perivascular spaces. A characteristic erythrophagocytosis was detected in inguinal lymph nodes, lung and bone marrow. Case 2 revealed calcification and necrotic lesions in the brain. In the necrotic areas, parenchymal calcification, vascular medial calcification, and occlusion of many vessels due to subendothelial fibrosis were detected. The areas of necrosis correlated with the distribution of occluded vessels. These changes were most prominent in putamen, internal capsule, thalamus and dentate nucleus. Hypercytokinemia is suspected to be the underlying mechanism for the clinical and laboratory findings in patients with FEL, although the relationship to the vascular pathology is unclear.  相似文献   
23.
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.  相似文献   
24.
H Kuwano  H Takano  K Sugimachi 《Endoscopy》1989,21(4):188-190
We treated a male teenager with a solitary gastric Peutz-Jeghers type (hamartomatous) polyp showing neither mucocutaneous pigmentation nor inheritance. X-ray studies of the upper gastro-intestinal tract, small intestine and barium enema revealed a solitary thumb tip-sized polypoid mass in the posterior wall of the gastric body, with no evidence of any associated lesion. Histologically, the polypoid mass showed typical features of a Peutz-Jeghers type (hamartomatous) polyp. This may be the first documentation of a "solitary" gastric Peutz-Jeghers type polyp, in the absence of familial polyposis coli and mucocutaneous pigmentation.  相似文献   
25.
Recent data have shown the existence of specific changes in mRNAs in thyroid carcinomas. It has not been clarified, however, why these changes clearly distinguish benign tissues from carcinomas, while genomic alternation such as mutations in the RAS or P53 genes do not. Further, the widely believed hypothesis, multi-step carcinogenesis, does not explain some clinical and experimental evidence of thyroid carcinomas. Considering these facts, we propose a new idea for thyroid carcinogenesis called "germ-cell carcinogenesis", in which cancer cells are derived from the remnant of fetal thyroid germ cells(thyroblasts) instead of normal thyroid follicular cells. Utilizing such mRNAs, we have established a new method for preoperative molecular-based diagnosis of thyroid carcinomas, Aspiration Biopsy Nucleic Acid Diagnosis(ABND). ABND allows us to perform preoperative nucleic acid analyses of the tumors by extracting RNAs or DNAs from tumor cells obtained by fine needle aspiration biopsies(FNABs). Pathological diagnosis of thyroid follicular carcinoma is quite difficult, and the establishment of preoperative molecular-based diagnosis of follicular carcinoma has been long expected. We found that quantification of the trefoil factor 3(TFF3)/galectin-3 mRNA ratio in thyroid tumor cells is a useful tool for distinction between follicular adenomas and carcinomas. Because ABND can be performed without any severe invasion to the patients, in the near future, when more reliable systems of quantitative RNA analysis have been developed, ABND will probably become one of the standard tests for preoperative diagnosis of thyroid carcinoma.  相似文献   
26.
27.
An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis.  相似文献   
28.
Summary Various doses of tetanus toxin were injected into three hind leg and two fore leg muscles of the rat. The neuromuscular transmission was tested by recording the mass action potential of the muscles elicited by a single electrical stimulus to the motor nerve after strong symptoms of local tetanus had developed. The muscle responses were depressed and blocked at lower toxin doses in the fast tibialis anterior than in the mixed gastrocnemius latemlis, while blocking of the slow soleus required the highest dose. The extensor carpi radialis and the flexor carpi ulnaris muscles showed medium sensitivity. In all five muscles the contraction time was measured and correlated with its individual minimal blocking dose. The more phasic (i.e., the faster) the muscle, the more sensitive its neuromuscular transmission was to tetanus toxin. The proportional distribution of red, white, and intermediate fibres, which are associated with specific end-plate types, was evaluated for the five muscles. The percentage of white fibres in the muscles displayed a very good negative correlation with the blocking dose. The relation between structures of end-plates and effects of tetanus toxin were analysed and it is suggested that the differences in sensitivity to tetanus toxin in the neuromuscular transmission in the five muscles is determined by a differential distribution of endplates with varying sensitivities to this toxin due to structural properties.This study is a part of a doctoral dissertation submitted by one of the authors (H.K.) to the Faculty of Medicine, University of Göttingen. Some of the results were presented at the 48th and 49th Congr. of German Physiol. Soc. (Kretzschmar et al., 1977, 1978) and at the 5th Internat. Conf. on Tetanus (Kretzschmar et al., 1979)  相似文献   
29.
A survey of AFM1 residues in 58 commercial milk powder samples was carried out using an enzyme‐linked immunosorbent assay (ELISA) based on a monoclonal antibody against aflatoxin M1 (AFM1). The samples were collected from the USA (10), China (28), Italy (14), New Zealand (3) and Poland (3). The ELISA was performed without the need for clean‐up procedures. The data revealed that 4 (US), 21 (Chinese) and 1 (Polish) samples were positive for AFM1, with an average of 95.5, 102.8 and 85.0 pg g‐1 of the AFM1respectively.  相似文献   
30.
Monoclonal antibody 303 (mAb 303) reacts with the high molecular weight agglutinin present in human saliva. Its reactivity is periodate sensitive, and it has been shown to recognize the Y epitope. Immunogold labeling of thin sections of human parotid and submandibular glands with mAb 303 showed reactivity in secretory granules of serous acinar, intercalated and striated duct cells (Takano et al., 1988). We now report that the apical and basolateral membranes of salivary acinar and duct cells are labeled by mAb 303, but not myoepithelial cells, endothelial cells and other mesenchymal cells. Gold particles were confined to acinar and duct cell membranes even when myoepithelial cells were directly adjacent, suggesting that the epitope resides on a membrane glycoprotein and that the label does not represent secreted agglutinin bound to the cell surface. Although myoepithelial cells are thought to differentiate from epithelial stem cells, the present results indicate that substantial compositional differences exist between the membranes of myoepithelial cells and other salivary parenchymal cells. Earlier studies also showed that mAb 303 labels normal pancreatic acinar cells and certain salivary (pleomorphic adenoma) and mammary (lactating adenoma) tumors (Bogert et al., 1988). This antibody thus may be a useful reagent for characterizing the origin of exocrine gland-derived cell cultures and neoplastic cells. Further, localization studies may provide insight into the role of the Lewis blood group-related epitope in secretory cells.  相似文献   
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