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11.
OBJECTIVE: We constructed a passive cigarette-smoking model with rats to investigate the molecular mechanism of intervertebral disc degeneration, and found by gene expression analysis that passive cigarette smoking stimulated the stress-responsive signal pathway and inhibited the apoptotic pathway. In this study, to clarify that these changes were derived from either nucleus pulposus (NP) or annulus fibrosus (AF), we separately collected NP and AF and quantitatively analyzed gene expression. METHODS: Total RNA was extracted from NP and AF of the lumbar intervertebral discs from rats which were kept in a smoking box for 4 and 8 weeks. Gene expression was measured by real-time PCR of cDNA synthesized from the total RNA. RESULTS: Stress-responsive protein, heat shock protein 70, was expressed similarly in NP and AF, and was upregulated to the same degree after 8 weeks of passive cigarette smoking. The protein tyrosine phosphatase gene was expressed more strongly in AF than in NP, and was upregulated after 8 weeks of smoking in both tissue parts. The type II collagen and aggrecan genes were predominantly expressed in AF and NP, respectively. CONCLUSION: These results indicate that passive cigarette smoking stimulates both NP and AF, and induces the stress-responsible genes such as heat shock protein 70 and protein tyrosine phosphatase in both.  相似文献   
12.
 Langerhans cell histiocytosis (LCH) has been thought to be a disorder of immune regulation, and increasingly, evidence showing that the tissue damage in LCH involves lymphokines and pro-inflammatory cytokines is reported. We detected human cytomegalovirus (HCMV)-DNA in LCH cells in the foci of LCH lesions by immunohistochemistry, in situ hybridization and PCR. HCMV was detected in the nuclei and/or cytoplasm of LCH cells in 9 of 27 LCH cases by immunostaining. HCMV was probably an early antigen. In situ hybridization revealed signals for HCMV-DNA only in the nuclei of LCH cells in 10 of the 27 LCH cases. PCR analysis was performed in 20 of the LCH cases, and HCMV-DNA was detected in 7 of these. All 7 positive cases were also positive for HCMV by ISH and IHC. These findings suggested that early phase infection or reactivation of HCMV occurred in the LCH lesions. HCMV infection may be accompanied by impaired cytokine production. Our study also suggested a relationship between HCMV infection and expression of TNFα. In tissues affected by LCH, dermatopathic lymphadenopathy or malignant fibrous histiocytoma and in normal tissues no signals for Epstein-Barr virus-RNA were detected. These findings suggest that in some cases LCH is associated with HCMV infection. Received: 24 November 1998 / Accepted: 24 April 1998  相似文献   
13.
14.
The cationic copolymerization of 1,3-dioxolane ( 1 ) with 5-methyl-2,3-dihydro-2-furanone ( 2 ) which has two functional groups, a carbon-carbon double bond and a lactone ring, was carried out with three triethyloxonium salts (Et3O+Y?, Y?: BF, FeCl and SbCl), with the boron trifluoride ethyl ether complex, and with tin tetrachloride in nitrobenzene, dichloromethane, and toluene at 0°C. On the basis of the NMR analysis of the microstructure of the copolymer, it was revealed that the growing species of 1 attacked exclusively the carbon-carbon double bond of 2 in the cross-propagation from 1 to 2 , regardless of the solvents and initiators used, except when triethyloxonium hexachloroantimonate was used as initiator. With the latter initiator, the ring opening reaction of 2 by the attack of the growing species of 1 occurred competitively with the usual vinyl addition, although the latter mode of reaction was predominant. The ring opening reaction of 2 with this initiator is probably caused by some specific interaction of monomer 2 with the counter anion.  相似文献   
15.
The copolymerization of 1,3-dioxolane ( 1 ) with 5-methyl-2,3-dihydro-2-furanone ( 2 ) was carried out in dichloromethane and nitrobenzene by use of triethyloxonium hexachloroantimonate, triethyloxonium hexafluoroantimonate, antimony pentachloride, antimony trichloride, and tin tetrachloride as initiators. The microstructures of the copolymers were analysed by means of 1H-NMR, showing that monomer 2 was incorporated into the copolymer chain by the ring-opening reaction as well as by the ?normal”? vinyl addition, when triethyloxonium hexachloroantimonate, triethyloxonium hexafluoroantimonate, and antimony pentachloride were used. On the basis of NMR and IR studies on the complexation of Lewis acids with γ-lactones, it was concluded that the prominent effect of the initiators observed in the copolymerization of 1 with 2 was mainly attributable to the coordination between the initiator and the γ-lactone ring of monomer 2 .  相似文献   
16.
Despite a multitude of reports on the classification and distribution of anterior pituitary cells, no previous study has attempted to obtain the three-dimensional (3D) and computer-graphic distribution pattern of each cell type in the whole pituitary. Therefore, we mapped the anterior pituitary cells of the house musk shrew ( Suncus murinus) and found a distinct cellular distribution pattern. Serial horizontal sections of whole shrew pituitaries were stained immunohistochemically for prolactin (PRL), growth hormone (GH), and adrenocorticotropic hormone (ACTH) cells. The contours of positive cells and the anterior, intermediate, and posterior lobes in each section were digitized for 3D visualization by a volume rendering method. The reconstructed images and virtual frontal and sagittal slices were examined in detail. On the 3D reconstructed images, the PRL and GH cells had similar distribution patterns, although the former were concentrated in the dorsolateral and ventrocentral portions, and the latter in the dorsocentral portions of the anterior lobe. On both sides of the pituitary stalk, there lay portions that were conspicuous by scarcity of PRL and GH cells. ACTH cells were widely scattered throughout the whole anterior lobe, but they were very few in the above portions and the dorsocentral portions where GH cells were concentrated. No sex difference in the distribution patterns of each cell type was observed. However, PRL cells in females were more numerous than in males, whereas the opposite was true for GH and ACTH cells. We discuss the relationship between the formation of the spatial distribution patterns and anterior pituitary ontogeny.  相似文献   
17.
18.
To investigate the correlation between argyrophilic nucleolar organizer regions (Ag-NORs)and the malignant potential of breast tumors, we analyzed Ag-NORs of cytological specimens obtained from 190 patients with various types of breast disease by preoperative aspiration biopsy. The average number of Ag-NORs per nucleus was defined as the Ag-NOR score. The Ag-NOR score was 5.7 +/- 1.7 in the group of women with breast carcinoma (n =70), 2.6= 0.4 in the group with fibroadenoma (n= 54) and 2.9= 0.6 in the group with mastopathy (n= 66). The level was significantly higher in breast carcinoma than in each benign disease(P < 0.001 in both cases). The score was 6.5 +/- 2.3 in the group with four or more metastatic lymph nodes (n = 21), 5.2+/- 1.2 in the group with one to three metastatic lymph node (n= 10) and 5.1+/- 1.1 in that with no metastatic lymph node (n = 39);the score was significantly (P < 0.05) higher in the groups with four or more metastatic lymph modes than in the other groups, respectively. Thus, a correlaton was observed between the Ag-NOR score and lymph node status. These data suggest that a higher Ag-NOR score reflects high-grade malignancy.  相似文献   
19.
Treatment of Lethal Midline Granuloma Type Nasal T-Cell Lymphoma   总被引:7,自引:0,他引:7  
Nasal T-cell lymphoma of the LMG type (LMG-NTL) is characterized by progressive, unrelenting ulceration, and necrosis of the nasal cavity and midline facial tissues. The clinical behavior of this tumor in 16 patients is compared with that of a nasal lymphoma of non-LMG-NTL type (non-LMG-NTL) in 8 patients and a paranasal sinus lymphoma (PSL) in 6 patients. All patients had stage I or II disease. Fourteen of the 16 patients with LMG-NTL received chemotherapy before and/or after radiotherapy. Cause-specific 5-year survival rates for patients with LMG-NTL, non-LMG-NTL, and PSL were 22%, 75%, and 67%, respectively. Seven patients with LMG-NTL, had complete response, although 3 recurred, whereas it was incomplete in 9 patients. The data indicates that it is desirable to deliver 50 Gy or more to achieve in-field control of LMG-NTL.  相似文献   
20.
Objective: To evaluate the effect of prednisolone plus low-dose aspirin (PSL/LDA) in women with autoimmune conditions who were enrolled in an IVF-ET program.

Design: A retrospective clinical study.

Setting: In vitro fertilization unit, Niigata University Hospital, Niigata, Japan.

Patient(s): Three hundred seven women who underwent IVF-ET between January 1996 and December 1997.

Intervention(s): Prednisolone (10 mg/d) and aspirin (81 mg/d) were administered to the women with autoantibodies who chose to participate.

Main Outcome Measure(s): Pregnancy and implantation rates with IVF-ET.

Result(s): Women undergoing IVF who had positive antinuclear antibodies, with or without antiphospholipid antibodies, had significantly lower pregnancy and implantation rates than did women without autoantibodies (14.8% versus 21.7% and 6.8% versus 10.4%, respectively). The administration of PSL/LDA to women with antinuclear antibodies significantly improved the outcome of IVF-ET (40.6% pregnancy rate and 20.3% implantation rate).

Conclusion(s): A high proportion of women who are undergoing IVF-ET have autoantibodies, which are associated with poor IVF outcomes. The administration of PSL/LDA to these women may improve their implantation rate.  相似文献   

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