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51.
A. Al Saadi Joseph F. Juliar John Harm A. Joseph Brough Eugene v. Perrin Harold Chen 《Clinical genetics》1976,9(1):43-50
Two live-born cases, 69,XXY and one stillbirth, 69,XXX are reported. Further evidence is presented to delineate the triploidy syndrome. Common external and internal features which characterize the triploidy syndrome are low-set ears, hypertelorism, colobomata, syndactyly, simian creases, microphallus, undescended testes, scrotal aplasia, anomalous heart and hypoplasia of kidneys and adrenals. The triploidy syndrome encompasses features found in trisomies 13, 18 and 21. We suggest that the abnormal development of the triploidy infants is the result of the mentioned trisomies and their subsequent effect on the remaining genome. 相似文献
52.
Emergence of influenza A H1N2 reassortant viruses in the human population during 2001 总被引:8,自引:0,他引:8
Gregory V Bennett M Orkhan MH Al Hajjar S Varsano N Mendelson E Zambon M Ellis J Hay A Lin YP 《Virology》2002,297(1):1-7
A recombinant vaccinia virus encoding rotavirus protein NSP3 driven by an internal ribosome entry site (IRES) from the encephalomyocarditis (EMC) virus was able to abate protein synthesis in BSC1 cells by 25-fold, with as much as 30% of the remaining protein synthesis being NSP3. Hence NSP3 shuts off host cell protein synthesis down to the level seen during rotavirus infection but is unable to prevent translation from EMC IRES-driven genes. This effect was abolished by deletions in the eIF4G-binding (aa 274-313) and the dimerization (aa 150-206) but not the viral mRNA-binding (aa 83-149) domains, supporting that NSP3 functions in vivo as a dimer. Binding of eIF4G by NSP3 has been implicated in interfering with mRNA 5'-3' circularization, hence such circularization is essential for translation in mammalian cells. 相似文献
53.
STUDY OBJECTIVES: To use near-infrared spectroscopy to investigate the effect of obstructive sleep apnea on cytochrome oxidase, the terminal enzyme of the mitochondrial respiratory chain. DESIGN: Observational study. SETTING: Teaching hospital sleep unit. PATIENTS: Subjects with diagnosed moderate to severe obstructive sleep apnea were recruited from the sleep clinic. INTERVENTIONS: Subjects were invited to attend 2 daytime sleep-study sessions, which included near-infrared monitoring of cerebral oxygenation and cytochrome-oxidase oxidation state. In addition, in study session 1, full polysomnography was performed (8 subjects, 303 apneas), and in study session 2, arterial oxygen saturation, cerebral blood flow velocity, and blood pressure were monitored (7 subjects, 287 apneas). MEASUREMENTS AND RESULTS: In study session 1, mean (+/- SD) cytochrome-oxidase changes ranged from 0.48 +/- 0.08 microM to 0.13 +/- 0.05 microM. The magnitude of cytochrome-oxidase change correlated significantly with the magnitude of change in the cerebral tissue oxygenation index (P < .001). In study session 2, there were significant correlations between arterial oxygen-saturation changes and cytochrome-oxidase redox changes and between Doppler cerebral blood flow velocity changes and cytochrome-oxidase redox changes (P < .001 and P = .001, respectively). CONCLUSIONS: Changes in directly measured cerebral tissue saturation and changes in arterial saturation and cerebral blood flow velocity (the 2 main factors affecting cerebral oxygenation) are associated with changes in cytochrome-oxidase oxidation state. The reduced cerebral oxygenation that occurs during obstructive sleep apnea is associated with changes in the intracellular redox state. 相似文献
54.
In ovarian neoplasms, BRAF, but not KRAS, mutations are restricted to low-grade serous tumours 总被引:7,自引:0,他引:7
Sieben NL Macropoulos P Roemen GM Kolkman-Uljee SM Jan Fleuren G Houmadi R Diss T Warren B Al Adnani M De Goeij AP Krausz T Flanagan AM 《The Journal of pathology》2004,202(3):336-340
Genes of the RAF family, which mediate cellular responses to growth signals, encode kinases that are regulated by RAS and participate in the RAS/RAF/MEK/ERK/MAP-kinase pathway. Activating mutations in BRAF have recently been identified in melanomas, colorectal cancers, and thyroid and ovarian tumours. In the present study, an extensive characterization of BRAF and KRAS mutations has been performed in 264 epithelial and non-epithelial ovarian neoplasms. The epithelial tumours ranged from adenomas and borderline neoplasms to invasive carcinomas including serous, mucinous, clear cell, and endometrioid lesions. It is shown that BRAF mutations in ovarian tumours occur exclusively in low-grade serous neoplasms (33 of 91, 36%); these included serous borderline tumours (typical and micropapillary variants), an invasive micropapillary carcinoma and a psammocarcinoma. KRAS mutations were identified in 26 of 91 (29.5%) low-grade serous tumours, 7 of 49 (12%) high-grade serous carcinomas, 2 of 6 mucinous adenomas, 22 of 28 mucinous borderline tumours, and 10 of 18 mucinous carcinomas. Of note, two serous borderline tumours were found to harbour both BRAF and KRAS mutations. The finding that at least 60% of serous borderline tumours harbour mutations in two members of the ERK-MAP-kinase pathway (BRAF 36%, KRAS 30%) compared with 12% of high-grade serous carcinomas (BRAF 0%, KRAS 12%) indicates that the majority of serous borderline tumours do not progress to serous carcinomas. Furthermore, no BRAF mutations were detected in the other 173 ovarian tumours in this study. 相似文献
55.
Aléssio AC Annichino-Bizzacchi JM Bydlowski SP Eberlin MN Vellasco AP Höehr NF 《American journal of medical genetics. Part A》2004,(3):256-260
Hyperhomocysteinemia is a risk factor for thrombosis, and methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) polymorphisms, folate, and B12 levels could contribute to plasma homocysteine (Hcy) variation. Although well established in adults, few studies have been performed in childhood. In this study, we investigated association of polymorphisms C677T and A1298C in the MTHFR gene and A66G in the MTRR gene with Hcy levels in children. These polymorphisms, as well as Hcy, folate, and vitamin B12 levels were investigated in 220 normal children with ages ranging from 1 to 8 years. Plasma Hcy, folate, and vitamin B12 levels were normal in all children. None of the polymorphisms could be considered an independent risk factor for hyperhomocysteinemia during childhood. The median Hcy levels in 37 children (17%) doubly heterozygous for C677T and A1298C mutations in the MTHFR gene were not different from the other genotypes. However, the association of the different genotypes with Hcy, folate, and vitamin B12 levels demonstrated significant P-values. The folate levels demonstrated a statistically significant decrease (P = 0.0477) from the C677T mutation in the MTHFR gene (TT genotype) when compared to the other groups. Folate was the only independent risk factor for hyperhomocysteinemia. Thus, monitoring the concentrations of folate would be more helpful for evaluating hyperhomocysteinemia and for preventing cardiovascular disease. 相似文献
56.
Haseeb Khan Ahmad Saleh Al Deeb Khalaf Al Moutaery Mohammad Tariq 《Experimental and toxicologic pathology》2003,55(2-3):181-186
A direct association between aging and drug-induced dyskinesia has been reported by several investigators. Iminiodipropionitrile (IDPN), a prototype nitrile compound produces a motor syndrome in rodents, which resembles neuroleptic drug induced dyskinesia. In this investigation attempt has been made to study the effect of age on IDPN induced vestibular hair cell degeneration and resulting dyskinetic syndrome. Male Wistar rats aged 3, 6 and 12 weeks received IDPN in the doses of 0, 200 and 400 mg/kg, intraperitoneally for 3 consecutive days. IDPN-induced dyskinesia was assessed using a behavioral testing battery on days 3, 4, 5, 6, 7, 14, 21 and 28. The rats were sacrificed on day 28; temporal bones were excised for vestibular histopathology and sera were collected for measuring the indices of oxidative stress (glutathione and conjugated dienes). IDPN in the dose of 200 mg/kg produced dyskinesia in 12 weeks old rats, but failed to do so in 3 and 6 weeks old rats. The high dose of IDPN (400 mg/kg) caused dyskinesia in all age groups, however, its onset and severity were age-dependent. Older rats showed an early onset and significantly high incidence of dyskinesia as compared to younger rats. The susceptibility of rats to IDPN-induced behavioral deficits was proportional to oxidative stress and degeneration of sensory hair cells in the crista ampullaris. 相似文献
57.
Alamawi S Abutaleb A Qasem L Masoud S Memish Z Al Khairy K Kheir O Bernvil S Hajeer AH 《British journal of biomedical science》2003,60(2):102-104
HIV-1 p24 antigen testing was introduced to increase sensitivity in the early detection of HIV infection in blood donors. Since the introduction of HIV-1 p24 antigen testing in Saudi Arabia, we have failed to detect a single positive case. Over a three-year period, only four indeterminates were detected out of 24,654 blood donors. All four proved negative by confirmatory testing. Based on this experience, we believe that resources would be better directed to pooled nucleic acid testing and that p24 serological testing should be abandoned. 相似文献
58.
Hira Shakoor Jack Feehan Vasso Apostolopoulos Carine Platat Ayesha Salem Al Dhaheri Habiba I. Ali Leila Cheikh Ismail Marijan Bosevski Lily Stojanovska 《Nutrients》2021,13(3)
Functional and nutraceutical foods provide an alternative way to improve immune function to aid in the management of various diseases. Traditionally, many medicinal products have been derived from natural compounds with healing properties. With the development of research into nutraceuticals, it is becoming apparent that many of the beneficial properties of these compounds are at least partly due to the presence of polyphenols. There is evidence that dietary polyphenols can influence dendritic cells, have an immunomodulatory effect on macrophages, increase proliferation of B cells, T cells and suppress Type 1 T helper (Th1), Th2, Th17 and Th9 cells. Polyphenols reduce inflammation by suppressing the pro-inflammatory cytokines in inflammatory bowel disease by inducing Treg cells in the intestine, inhibition of tumor necrosis factor-alpha (TNF-α) and induction of apoptosis, decreasing DNA damage. Polyphenols have a potential role in prevention/treatment of auto-immune diseases like type 1 diabetes, rheumatoid arthritis and multiple sclerosis by regulating signaling pathways, suppressing inflammation and limiting demyelination. In addition, polyphenols cause immunomodulatory effects against allergic reaction and autoimmune disease by inhibition of autoimmune T cell proliferation and downregulation of pro-inflammatory cytokines (interleukin-6 (IL-6), IL-1, interferon-γ (IFN-γ)). Herein, we summarize the immunomodulatory effects of polyphenols and the underlying mechanisms involved in the stimulation of immune responses. 相似文献
59.
60.
Haitham Elbardisi Ahmad Majzoub Christiana Daniel Fadwa Al.Ali Mohamed Elesnawi Kareim Khalafalla Ashok Agarwal Ralf Henkel Alia Alattar Ibrahim Al-Emadi Mohamed Arafa 《Andrologia》2021,53(8):e14135
In this study, we investigated the prevalence of sexual dysfunction among males with advanced chronic kidney disease and the effect of treating hyperprolactinemia among these patients. In this prospective study, patients were assessed with history, physical examination, hormonal assessment, and two questionnaires, IIEF and AIPE. Patients with hyperprolactinemia received treatment with cabergoline 0.5 mg once per week for 6 months and were re-evaluated. A total of 102 patients were included in this study, 75 (73.53%) were on hemodialysis, 13 (12.75%) on peritoneal dialysis and 14 (13.73%) on medical treatment alone. Ninety (88.24%) patients had premature ejaculation, 85 (83.33%) had anything from mild-to-moderate-to-severe erectile dysfunction. The incidence of hypogonadism and hyperprolactinemia was 34.4%. Patients treated with cabergoline (n = 26) showed a significant increase in LH levels (p = .003) and a significant decrease in prolactin levels (p = .003). Testosterone levels and the incidence of erectile dysfunction or premature ejaculation did not improve significantly. There is a high incidence of sexual dysfunction among patients. Treatment of hyperprolactinemia is effective in correcting prolactin levels, but does not improve erectile dysfunction or premature ejaculation. Therefore, treating hyperprolactinemia is not an overall effective treatment for erectile dysfunction in these patients. 相似文献