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61.
62.
Aortic stenosis(AS)is the most common valvular disease in the older adults'population,and its prevalence will likely continue to increase with the aging society.[1]Surgical aortic valve replacement(SAVR)for elderly patients is known as a high-risk procedure.[2-4]Transcatheter aortic valve implantation(TAVI)is a reasonable alternative to SAVR for older and inoperable patients with AS,and TAVI significantly improves outcomes in elderly patients with severe AS and serious comorbidities,[5,6]TAVI achieves a 20%relative reduction in mortality compared with SAVR.  相似文献   
63.
Recently, cytoreductive prostatectomy for metastatic prostate cancer (mPCa) has been associated with improved oncological outcomes. This study was aimed at evaluating whether robot-assisted radical prostatectomy (RARP) as a form of cytoreductive prostatectomy can improve oncological outcomes in patients with mPCa. We conducted a retrospective study of twelve patients with mPCa who had undergone neoadjuvant therapy followed by RARP. The endpoints were biochemical recurrence-free survival, treatment-free survival, and de novo metastasis-free survival. At the end of the follow-up period, none of the enrolled patients had died from PCa. The 1- and 2-year biochemical recurrence-free survival rates were 83.3% and 66.7%, respectively, and treatment-free survival rates were 75.0% and 56.3%, respectively. One patient developed de novo bone metastases 6.4 months postoperatively, and castration-resistant prostate cancer 8.9 months postoperatively. After RARP, the median duration of recovery of urinary continence was 5.2 months. One patient had severe incontinence (>2 pads/day) 24 months postoperatively. RARP may be a treatment option in patients with mPCa who have achieved a serum prostate-specific antigen level < 0.2 ng/mL, and present without new lesions on imaging.  相似文献   
64.
Urodele amphibians (newts and salamanders) are important animal models for understanding regeneration mechanisms and genome evolution. We constructed ideograms of BrdU/dT- and C-banded karyotypes in the Japanese fire-belly newt, Cynops pyrrhogaster, which is useful as a model animal with extremely high ability of regeneration. We also established a high-resolution FISH mapping system for newts, and localized satellite DNA sequences, 18S rDNAs, telomeric (TTAGGG)n repeats and seven functional genes, including genes associated with lens regeneration, tyrosinase and two types of gamma crystallins, to chromosomes of the newt. The 18S rDNAs were localized to three chromosomal pairs in males, whereas the chromosomal locations were highly variable in females. No hybridization signals were detected for the telomeric (TTAGGG)n sequence. All three lens regeneration-related genes were mapped on the short arm of chromosome 7, suggesting that the location of the genes in the same linkage group may be correlated with the regulation of gene expression associated with chromatin dynamics in interphase nuclei during regeneration. The chromosomal distribution and nucleotide sequences of pericentric satellite DNA sequences were well conserved between C. pyrrhogaster and European newts; in contrast, there was species specificity of nucleotide sequences for centromere-specific satellite DNAs.  相似文献   
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Background Nectins are Ca2+-independent immunoglobulin (Ig)-like cell-cell-adhesion molecules. We have generated transgenic mice expressing a series of soluble forms of nectin-1, and investigated special effects of each soluble form of nectin-1 in vivo. In the course of generating transgenic mice expressing a soluble form of nectin-1 consisting of the first Ig-like domain of nectin-1 and the Fc portion of human IgG1 (PHveC-VhIg), we found that all of the transgenic founder mice showed a microphthalmia. The purpose of this study is to examine functions of the extracellular domains of nectin-1 in eye development using transgenic technology. Methods Eyes of four different transgenic mouse lines expressing each soluble form of nectin-1 were analyzed histologically. Tissue sections were processed with hematoxylin-eosin staining and indirect immunoperoxidase technique. Results All of five transgenic mouse founders expressing PHveC-VhIg, and of three lines expressing PHveC-VpIg made of the first Ig-like domain fused to porcine Fc portions at 5 weeks showed a microphthalmia, but not all of the transgenic mouse lines expressing PHveCIg or PHveCpIg made of the entire ectodomain fused to human or porcine Fc portions. In the abnormal eyes, the vitreous body was almost absent. In PHveC-VhIg-expressing mice at postnatal day 6, each vitreous space was very small. In the neonatal transgenic mice, the vitreous body was almost the same as that of control mice, and PHveC-VhIg was expressed in the optic nerve, conjunctival epithelium, ciliary body, corneal and lens epithelium. At this stage, nectin-1, -3 and -4 were stained in the optic nerve of control mice as well as in that of the transgenic mice. Nectin-1 is faintly stained in the epithelium of the cornea and lens epithelium, but not in the ciliary body. Conclusion Soluble forms of the first Ig-like domain of nectin-1 (PHveC-VhIg and PHveC-VpIg), but not those of the entire ectodomain (PHveCIg and PHveCpIg), lead to microphthalmia and lack of vitreous body in the transgenic mice. Transgenic mice generating group: Keiko Amagai, Minako Kuramochi, Yuki Watanabe and Shigeto Kouda (Sankyo Labo Service Corporation, Tokyo 132-0023, Japan).  相似文献   
67.
The methods we used to produce a carcinoma in the extrahepatic bile duct and gallbladder in hamsters are described along with the characteristics of the induced tumors. Female Syrian golden hamsters were first subjected to Cholecystoduodenostomy with dissection of the extrahepatic bile duct on the distal end of the common duct (CDDB) and were, 4 weeks later, treated with weekly subcutaneous injections of N-nitrosobis(2-oxopropyl)amine (BOP) at a dose of 10 mg/kg body weight for 9 weeks. The animals were killed at the 12th, 16th and 20th week after the initiation of BOP treatment. Extrahepatic bile duct carcinoma developed in 16%, 24% and 41% and gallbladder carcinoma occurred in 58%, 81% and 82% of the hamsters, respectively, at the corresponding times of killing. The incidences were significantly higher than those in sham-operated controls ( P <0.01). The induced extrahepatic bile duct carcinomas were predominantly of the polypoid type and gallbladder carcinomas were of the papillary type in growth form, being morphologically similar to early stage biliary carcinoma in humans. Immunohistochemical staining using bromodeoxynridine and anti-bromo-deoxyuridine monoclonal antibody demonstrated that the CDDB procedure greatly accelerated the cell kinetic activity of the biliary epithelium, and this was considered to be a major factor promoting the development of biliary carcinomas in this hamster model. In conclusion, this new model provides a high incidence of tumor development at the extrahepatic biliary tract and is expected to be useful for clarifying the characteristics of this highly malignant tumor.  相似文献   
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A case of mixed bacterial meningitis with congenital spinal epidermoid is reported. E. coli and S. faecalis were isolated simultaneously from the cerebrospinal fluid of a 14-month-old girl who had a continuing fever for 5 days. The clinical response was very poor, whereas bacteria detected showed high sensitivity in vitro to the antibiotics used clinically. Thus a myelography and a CT scanning of the lumbosacral region were performed one month after admission, when a spinal epidermoid was forced, containing an abscess connected to a thin dermal sinus which could not be recognized macroscopically. The patient recovered completely after surgical treatment.  相似文献   
70.
The aim of this study was to examine whether the type of bilioenterostomyenhances biliary carcinogenesis in the hamster model. Syrianhamsters were divided into the following groups; simple laparotomy(control group), cholecystoduodenostomy with dissection of theextrahepatic bile duct on the distal end of the common duct(CDDB group) and cholecystoileostomy with dissection of theextrahepatic bile duct on the distal end of the common duct(CIDB group). Following these procedures, all hamsters receivedN-nitrosobis(2-oxopropyl)amine. The diameter of the extrahepaticbile duct and plasma levels of cholecystokinin (CCK) were measuredand the number of neoplastic lesions was counted microscopically.Proliferative effect of the procedures on the biliary epitheliumwas examined by proliferative cell nuclear antigen. In the CDDBgroup the extrahepatic bile duct was significantly dilated andcarcinogenesis of the gall-bladder and extrahepatic bile ductswas enhanced. In the CIDB group the CCK bioactivity was stimulatedand intrahepatic biliary duct, but not gall bladder and extrahepaticbile duct, carcinogenesis was promoted more than that observedin the CDDB group. Proliferation of the biliary duct epitheliumwas enhanced in both the CDDB and CIDB groups. Cholecystoduodenostomyenhanced intra- and extrahepatic bile duct carcinoma, whereascholecystoileostomy promoted only intrahepatic bile duct carcinoma.Some factors in the intestinal juice seem to play a role inthe promotion of biliary tract carcinoma.  相似文献   
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