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71.
PURPOSE: The purpose of this study was to determine the incidence of human papillomavirus deoxyribonucleic acid (HPV DNA) in anal squamous carcinoma. METHODS: HPV DNA in situ hybridization for HPV Types 6, 11, 16, 18, 31, 33, and 35 was performed on the formalin-fixed, paraffinembedded tissue from 53 perianal and anal squamous carcinomas and 10 controls. RESULTS: HPV DNA sequences were identified in 18 of 53 anal squamous carcinomas (34 percent). All 10 controls were negative for HPV DNA. Of the 18 positive patients, 10 were perianal squamous carcinomas, and 8 were anal canal squamous carcinomas. Six of the perianal carcinomas were positive for HPV Types 6 and 11. The remaining four perianal carcinomas and all eight of the anal canal carcinomas were positive for HPV Types 16 and 18. CONCLUSION: HPV DNA sequences can be identified in anal squamous carcinomas. Anal squamous epithelium is another site where HPV infection may carry a risk for malignant transformation. One-third of anal squamous carcinomas may be associated with prior HPV infection. Patients with anogenital HPV infection should be routinely screened for anal squamous lesions.  相似文献   
72.
Haemophilus influenzae is an important respiratory pathogen. Emergence of resistance to various antibiotics is a major problem in patient management. A total of 90 strains of H. influenzae were characterized from specimens obtained from patients of acute respiratory tract infection; 13 (14.4%) belonged to type beta. On biotyping, 90% strains belonged to biotype II. The frequency of resistance to various antibiotics was as follows: cotrimoxazole 33.3% ampicillin 21.1%, cephalexin 7.8%, chloramphenicol 7.8%, ciprofloxacin 2.5% erythromycin and tetracycline 5% each. All the ampicillin-resistant strains produced beta-lactamase as detected by nitrocefin disc method. None of the strains exhibited resistance to cefaclor and third generation cephalosporins. The present study showed emergence of variable resistance to ampicillin, cotrimoxazole and other antibiotics. It is important for the clinical microbiology laboratory to monitor drug resistant strains for instituting appropriate antibiotic therapy of respiratory infections due to H. influenzae.  相似文献   
73.
Conjugation of ubiquitin to proteins is activated during spermatogenesis. Ubiquitination is mediated by ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzymes (UBCs or E2s), and ubiquitin protein ligases (E3s). Since we previously showed that the activated ubiquitination is UBC4 dependent, we characterized Rat100, a UBC4-dependent E3 expressed in the testis. Analysis of expressed sequence tag sequences and immunoblotting showed that Rat100 is actually a 300-kDa protein expressed mainly in the brain and testis and is similar to the human E3 identified by differential display (EDD) protein and the Drosophila hyperplastic discs gene, mutants of which cause a defect in spermatogenesis. Rat100 is induced during postnatal development of the rat testis, peaking at d 25. It is localized only in germ cells and is highly expressed in spermatocytes, moderately in round and slightly in elongating spermatids. In contrast to UBC4 whose removal from a testis extract abrogates much of the conjugation activity, immmunodepletion of Rat100 from the extracts had little effect. Rat100 therefore has a limited subset of substrates, some of which appear associated with the E3 as the immunoprecipitate containing Rat100 supported incorporation of (125)I-ubiquitin into high molecular weight proteins. Thus, Rat100 is the homolog of human EDD and likely of Drosophila hyperplastic discs. This homology, together with our results, suggests that induction of this E3 results in ubiquitination of specific substrates, some of which are important in male germ cell development.  相似文献   
74.
A Sodhi  K Pai 《Neoplasma》1992,39(4):211-217
The supernatants collected from cisplatin, lipopolysaccharide (LPS), muramyl dipeptide (MDP) or recombinant interferon gamma (rIFN-gamma) treated non-adherent mononuclear cells (with NK cell activity) enhanced thymocyte proliferation by a submitogenic concentration of concanavalin A as compared to untreated nMNC. Supernatants collected from cisplatin or rIFN-gamma treated nMNC also demonstrated enhanced cytotoxicity against actinomycin-D treated L929 cells, suggesting that cisplatin or rIFN-gamma treated nMNC release tumor necrosis factor (TNF) into the culture supernatant. On the other hand, supernatant collected from untreated nMNC showed little TNF activity. Treatment of nMNC with cisplatin, LPS, MDP or rIFN-gamma resulted in enhanced release of lysozyme into the culture medium as compared to untreated nMNC.  相似文献   
75.
Fertilization and gestation are intrafollicular in the guppy (Poecilia reticulata), and ovulation occurs at the end of gestation prior to parturition. In this study, the effects in vivo of the ovarian steroids, progesterone, 17 alpha,20 beta-dihydroxy-4-pregnen-3-one (17 alpha,20 beta-P), cortisol and estradiol-17 beta, the antiprogestin RU 486, and aromatase inhibitor, 4-hydroxyandrost-4-ene-3,17-dione (4-HAD), on gestation and parturition were studied in the guppy. Progesterone (0.05 and 0.10 micrograms/ml of water), 17 alpha,20 beta-P (0.01 micrograms/ml and greater), cortisol (0.10 micrograms/ml) and 4-HAD (0.10 micrograms/ml) all prolonged gestation presumably by inhibiting ovulation. 17 alpha,20 beta-P was most effective in inhibiting ovulation and parturition for up to 36 days postpartum. This inhibition was reversed when fish were transferred to steroid-free water. Besides extending gestation, 17 alpha,20 beta-P and 4-HAD also inhibited development of vitellogenic oocytes. Estradiol-17 beta (0.05 and 0.10 micrograms/ml) and RU 486 (10 micrograms/g body weight) both induced premature parturition presumably by accelerating onset of ovulation. These results, together with our previous observations on the steroid profile in the guppy, strongly suggest roles for estradiol-17 beta and cortisol in regulating ovulation and parturition.  相似文献   
76.
Objective: Folate metabolism involves absorption, transport, modifications and interconversions of folates. The reduced folate carrier does not participate directly in folate metabolism but plays a major role in intracellular transport of metabolically active 5-methyltetrahydrofolate and maintains the intracellular concentrations of folate. The purpose of this study was to identify the prevalence of reduced folate carrier 1 (RFC1) A80G polymorphism and to further delineate its association with non-syndromic cleft lip and palate (NSCLP) in a south Indian population.

Methods: In the present case-control study, we studied RFC1 gene A80G polymorphism to evaluate its impact on NSCLP risk in south Indian population. Blood samples of 142 cases with NSCLP and 141 controls were collected and genotyped using PCR-RFLP.

Results: The genotype distribution in the control group followed Hardy–Weinberg equilibrium (p?=?0.633). The G allele frequency of cases was 64.8% (184/284) and was significantly lower than that found in the control group 56.4% (160/282). The genotype distributions between NSCLP cases and controls was not significantly different (p?=?0.131). The allelic model significantly increased the risk of NSCLP (G versus A; OR?=?1.40; 95% CI: 1.00–1.97; p?=?0.050). In subgroup analysis, the A80G variant showed significant association for the CLP group in dominant and allelic models.

Conclusions: Altogether, our findings support the hypothesis that RFC1 A80G variant may contribute to NSCLP susceptibility in a south Indian population.  相似文献   

77.
After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.  相似文献   
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