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851.
Abstract. Background Condyloma acuminata is the most common anorectal lesion in patients infected with human immunodeficiency virus (HIV). Surgical treatment can be challenging in cases where the size and extension into the anal canal make individual excision impossible. These patients require large resections and reconstruction using grafts or local flaps.Methods Six patients were treated for giant perianal condylomas between 1999 and 2001. Four patients were HIV–positive, and were selected for surgical intervention after achieving a T4 count >350 and low viral replication. In 5 cases, the lesions were circularly resected up to the pectinate line and the defect was reconstructed using a bilateral V–Y plasty. In the remaining case, fulguration was possible on one side and a unilateral V–Y plasty was performed.Results There were no infections or healing delays in this series, and the functional and aesthetic results are satisfactory.Conclusion V–Y plasties are a valid method for perianal reconstruction after resection of giant anal condyloma, with good results in selected patients with HIV infection.  相似文献   
852.
BACKGROUND: Cytosolic aldehyde dehydrogenase, or ALDH1A1, functions in ethanol detoxification, metabolism of neurotransmitters, and synthesis of retinoic acid. Because the promoter region of a gene can influence gene expression, the ALDH1A1 promoter regions were studied to identify polymorphism, to assess their functional significance, and to determine whether they were associated with a risk for developing alcoholism. METHODS: Sequence analysis was performed in the promoter region by using Asian, Caucasian, and African American subjects. The resulting polymorphisms were assessed for frequency in Asian, Caucasian, Jewish, and African American populations and tested for associations with alcohol dependence in Asian and African American populations of alcoholics and controls. The functional significance of each polymorphism was determined through in vitro expression analysis by using HeLa and HepG2 cells. RESULTS: Two polymorphisms, a 17 base pair (bp) deletion (-416/-432) and a 3 bp insertion (-524), were discovered in the ALDH1A1 promoter region: ALDH1A1*2 and ALDH1A1*3, respectively. ALDH1A1*2 was observed at frequencies of 0.035, 0.023, 0.023, and 0.012 in the Asian, Caucasian, Jewish, and African American populations, respectively. ALDH1A1*3 was observed only in the African American population, at a frequency of 0.029. By using HeLa and HepG2 cells for in vitro expression, the activity of the luciferase reporter gene was significantly decreased after transient transfection of ALDH1A1*3-luciferase compared with the wild-type construct ALDH1A1*1-luciferase. In an African American population, a trend for higher frequencies of the ALDH1A1*2 and ALDH1A1*3 alleles was observed in a population of alcoholics (p = 0.03 and f = 0.12, respectively) compared with the control population. CONCLUSIONS: ALDH1A1*2 and ALDH1A1*3 may influence ALDH1A1 gene expression. Both ALDH1A1*2 and ALDH1A1*3 produce a trend in an African American population that may be indicative of an association with alcoholism; however, more samples are required to validate this observation. The underlying mechanisms contributing to these trends are still unknown.  相似文献   
853.
Summary The in vitro growth requirements of three human embryonal carcinoma cell lines (H 12.7, 2102 EP, 1428 A) were investigated. The basal medium DME/F12 supplemented with insulin, transferrin, and low-density and high-density lipoproteins was sufficient to support substantial multiplication of all three lines. The most efficient attachment factor was either fibronectin (for 2102 EP and 1428 A) or collagen type I (H 12.7). In a serum-free system the influence of epidermal growth factor (EGF), insulin-like growth factor I, multiplication stimulating activity (MSA), a platelet extract, and the glucocorticoids dexamethasone and hydrocortisone, as determined by the DNA synthesis rate of the cells, was generally minimal. However, the DNA synthesis rate of cell lines H 12.7 and 2102 EP was increased by MSA, and the line with the highest potential to differentiate (H 12.7) was stimulated by EGF. All three cell lines secreted growth factors in a heterologous stimulation assay. Insulin-like growth factors I and II were not part of the growth promoting activity. The inhibitory effect of a monoclonal anti-EGF antibody on the 3H-thymidine incorporation of cell line 2102 EP might indicate autocrine secretion of EGF or an EGF-like factor by this cell line.  相似文献   
854.
Interferon (IFN)-gamma is produced by T cells and natural killer cells and activates monocytes and dendritic cells (DCs). Recently, IFN-gamma has been shown to be produced by mouse DCs following stimulation with interleukin (IL)-12, which is markedly augmented by the addition of IL-18. We here analyzed whether human DCs secrete IFN-gamma in response to IL-12 and/or IL-18. Human immature DCs, generated from cord blood CD14(+) monocytes by treating with granulocyte-macrophage colony-stimulating factor and IL-4, were incubated with IL-12 and/or IL-18 and assayed for IFN-gamma production. IL-12, but not IL-18, weakly induced IFN-gamma production, while IL-12 together with IL-18 induced high levels of IFN-gamma production. Similar results were obtained with mature DCs, although levels of IFN-gamma production were less than those in immature DCs. Also with mature and immature DCs, IL-12 upregulated the expression of IL-18 receptor alpha (Ralpha), and costimulation with IL-12 and IL-18 upregulated CD40 expression. Anti-IL-18Ralpha antibody abrogated both the IFN-gamma induction and the CD40 upregulation by IL-12 plus IL-18. These findings suggest that IL-12 upregulates IL-18Ralpha expression on human DCs and acts synergistically with IL-18 to induce high levels of IFN-gamma, which subsequently enhances CD40 expression on DCs in an autocrine manner.  相似文献   
855.
Background:  The effects of ethanol on brain function are thought to be partly because of altered activity of ion channels that regulate synaptic activity. Results from previous studies from this lab and others have shown that ethanol inhibits the function of the N -methyl- d -aspartate (NMDA) receptors, a calcium-permeable ion channel activated by the neurotransmitter glutamate. Factors that influence the acute sensitivity of NMDA receptors to ethanol may be critical in determining how neurons and neuronal networks respond to the presence of ethanol. In this study, we have examined the effect of physiologically relevant concentrations of magnesium on the ethanol sensitivity of recombinant NMDA receptors and how ethanol inhibition under these conditions is influenced by the NR3A subunit.
Methods:  Recombinant cDNAs encoding NMDA receptor subunits were expressed in human embryonic kidney 293 cells. Whole-cell patch-clamp electrophysiology was used to measure currents induced by rapid application of glutamate in the absence and presence of ethanol.
Results:  In magnesium-free recording solution, ethanol inhibited glutamate-mediated currents in cells transfected with NMDA receptor subunits. The magnitude of ethanol inhibition was significantly enhanced when recordings were carried out in media containing 1 mM magnesium. This effect was reversible and required magnesium-sensitive receptors. Magnesium did not enhance ethanol inhibition of glycine-activated NR1/NR3A/NR3B receptors. However, NR3A co-expression prevented the enhancement of ethanol's inhibitory effect on receptors composed of NR2A but not NR2B subunits.
Conclusions:  These results suggest that under physiological conditions, NR3A may be an important regulator of the acute ethanol sensitivity of brain NMDA receptors.  相似文献   
856.
PURPOSE This study was designed to identify the location of the lateral ligaments of the rectum and to reveal its contents. METHODS From 18 human soft cadavers (9 males), 18 pelves were sagittally sectioned into 36 hemipelvic specimens affording good anatomic view of the lateral aspect of the rectum. All of them were dissected and mobilized by using sharp technique under direct vision by one surgeon to avoid confounding factor. The lateral ligaments of the rectum were identified and the distances from the center of its pelvic attachment to the promontory of sacrum and coccyx were measured. After measurement, they were transected and brought for histologic examination. RESULTS In 36 hemipelvic specimens, 18 lateral ligaments of the rectum were found on the right side of the rectum and 18 were found on the left side. One cadaver had no lateral ligament on the right side and another had two lateral ligaments on the right side 3-cm apart. The location of the lateral ligaments was posterolateral to the rectum. The distance from the lateral ligament to sacral promontory on right side was 8.14 ± 1.82 cm (mean ± standard deviation) and 8.14 ± 1.22 cm on left side. The distances from the lateral ligament to coccyx on the right and left sides were 5.12 ± 1.4 cm and 4.88 ± 1.29 cm, respectively. The content of the lateral ligaments of the rectum consisted of loose connective tissue with cluster of small nerves. No artery was detected in all specimens. The small arterioles and venules were discovered in only four specimens. CONCLUSIONS The lateral ligaments of the rectum were located at posterolateral side of the rectum. They were closer to the coccyx than to the sacral promontory. Its component was loose connective tissue containing multiple small nerves. There was no artery found in any lateral ligaments by histologic study. Small arterioles and venules were detected 11 percent. Presented at the meeting of The American Society of Colon and Rectal Surgeons, Dallas, Texas, May 8 to 13, 2004.  相似文献   
857.
人群蠕形螨寄生生态的观察   总被引:22,自引:2,他引:22  
目的:为了探讨蠕形螨的有关生态问题。方法:对正常体温和高于正常体温的不同人群作了人体蠕形螨检出率的比较。结果:毛囊蠕形螨多数寄生在毛囊内,颚体朝向毛囊底,少数朝向毛囊侧壁及毛囊口;皮脂蠕形螨皮表分布与毛囊蠕形螨大致相同,只是寄生毛囊内的皮脂蠕形螨的颚体仅见出或入皮脂腺方向。蠕形螨检出率夜间(74%)比白天(52%)高,体温增高(体温≥38℃)者(91.1%)比正常体温(66.7%)高,浴后(60.9%)比浴前(29.9%)高,环境温度0±1℃、10±1℃、20±1℃、30±1℃的检出率依次为28%、52%、62%和76%。各组间差别均具有显著意义(P<0.01)。结论:宿主体温及环境温度的变化对蠕形螨检出率有直接影响。夜间检出率增高似与温度或/和蠕形螨夜间爬到毛囊口或皮脂腺口交配有关。  相似文献   
858.
AIMS: In human atrial myocytes (HuAM) two beta-adrenergic receptors (beta-AR) and four splicing-variants of the serotonin 5-HT(4) receptor are present. Multiple coupling with G stimulatory (G(s)) and G inhibitory (G(i)) proteins has been proposed for both beta(2)-AR and 5-HT((4b)) subtypes, but no functional data exist in HuAM. Serotonin (5-HT) and catecholamines are able to trigger arrhythmias in human atrium, but the underlying cellular mechanisms are not completely understood. The pacemaker current (I(f)) is an inward Na(+)/K(+) current, constitutively present in HuAM and directly modulated by cAMP; I(f) could play a role in triggering human atrial arrhythmias. This study evaluated the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors by assessing the modulation of I(f) by selective stimuli. METHODS: HuAM were isolated from right atrial appendages and utilized for patch-clamp recording. The coupling of receptor subtypes with G(i) proteins was tested by incubating HuAM in pertussis toxin (PTX). RESULTS: Beta(1)-AR stimulation (Isoprenaline [ISO] + ICI 118,551), and 5-HT caused a concentration-dependent significant shift of the half activation potential of I(f) activation curve (DeltaV(h)), P < 0.01. beta(2)-AR stimulation (ISO 1 microM + CGP 20712A) also significantly shifted V(h) (P < 0.0001), but with DeltaV(h)[beta(2)-AR] significantly smaller than the effect caused by 1 microM beta(1)-AR stimulation (P < 0.05). Pre-treatment of HuAM with PTX did not alter the effect of beta(1)-AR stimulation (both 0.1 and 1 microM) and 1 microM 5-HT on I(f), but significantly increased the effect in response to beta(2)-AR stimulation and 0.1 microM 5-HT (P < 0.05 for both), thus suggesting a G(i) protein coupling of these receptors. CONCLUSIONS: Our results provide the first functional evidence of the different G protein coupling of beta(1)-AR, beta(2)-AR and 5-HT(4) receptors in HuAM. Further they support the view that I(f) current might play an important role in triggering catecholamines and serotonin-induced atrial arrhythmias.  相似文献   
859.
Summary Biopsies from 318 cases with squamous cell carcinoma of the uterine cervix, 48 with cervical and vulvar condylomata, 14 with cervical intraepithelial neoplasia (CIN), 34 with chronic cervicitis and 24 with normal cervical epithelium were collected from different geographic regions with different cervical cancer mortalities. The DNA · DNA dot-blot and Southern blot hybridization results show that there is a close relationship between HPV-16 and the uterine cervical squamous cell carcinoma in China. One very interesting observation is that the finding of HPV-16-homologous DNA differs significantly among five geographic regions, and corresponds with the mortalities from cervical cancer of these five regions. HPV-11 was found mainly in benign lesions. The rate of detection of HPV-16 in Chinese women increased from 8.3% in normal cervical epithelium to 20% in chronic cervicitis, 28% in cervical condyloma, 50% in CIN and 60.4% in cervical cancer. It is suggested that HPV-16 infection may be an etiological factor in the development of human cervical carcinoma. From the results of Southern blot hybridization, it appeared that HPV-16 DNA had been integrated into the genome of the host cell in cervical cancer. Whereas the HPV-16 DNA sequence was only present as an episome in normal cervical epithelium and cervical benign lesions. The rate of occurence of E6-E7 genes is the highest (88.9%) compared with that of other subgenomic fragments of HPV-16 in specimens of human cervical cancer in China. This implies that E6 and E7 may be the oncogenic genes of HPV-16 and play an important role in the carcinogenesis of human cervical epithelial cells. The amplification and rearrangement of the c-myc protooncogene are closely associated with the occurrence of cervical cancer. The results presented here revealed that the activated c-myc oncogene may cooperate with HPV-16 in the carcinogenic processes.Abbreviations HPV Human papillomavirus - CIN cervical intraepithelial neoplasia - SSC standard saline citrate  相似文献   
860.
BACKGROUND/AIMS: Liver failure is a life threatening condition currently treated by palliative measures and, when applicable, organ transplantation. The use of a bioartificial organ capable of fulfilling the main functions of the liver would represent an attractive alternative. However, the shortage of suitable donor cells, and their limited growth ability have impeded the development of this strategy. We investigated whether lentiviral vectors allow for conditional immortalization of human hepatocytes and whether these immortalized hepatocytes could reverse lethal acute liver failure. METHODS: We exposed primary human hepatocytes to Cre-excisable lentiviral vectors coding for SV40T Antigen, telomerase, and/or Bmi-1 and tested the functionality of the resulting cell lines. Therapeutic potential of immortalized hepatocytes were tested in a murine model of acetaminophen-induced hepatic injury. RESULTS: The immortalized hepatocytes grew continuously yet were non-tumorigenic, stopped proliferating when exposed to Cre recombinase, and conserved defining properties of primary hepatocytes, including the ability to secrete liver-specific proteins and to detoxify drugs. The implantation of encapsulated immortalized human hepatocytes rescued mice from lethal doses of acetaminophen. CONCLUSIONS: Lentiviral vectors represent tools of choice for immortalization of non-dividing primary cells, and lentivirally immortalized human hepatocytes are promising reagents for cell-based therapy of acute liver failure.  相似文献   
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