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91.
Four of 391 Ni-Vanuatu women were infected with variants of human T-cell leukemia virus type 1 (HTLV-1) Melanesian subtype C. These strains had env nucleotide sequences approximately 99% similar to each other and diverging from the main molecular subtypes of HTLV-1 by 6% to 9%. These strains were likely introduced during ancient human population movements in Melanesia.  相似文献   
92.
A nuclear morphometic assay for preosteoblasts is introduced as a cell-kinetic technique, applicable to routine histological preparations of mineralized tissue. Because this method is a morphological marker for osteoblast precursor cell differentiation, it provides a new dimension for determining the mechanism of osteoblast histogenesis. Osteoblast precursors of the periodontal ligament are a mixed population of progenitors, kinetically separable into two distinct groups according to nuclear size. Preosteoblasts, the immediate proliferating precursors of osteoblasts, have large nuclei (>170 μm3) and are derived from relatively undifferentiated fibroblastlike cells, which have smaller nuclei (<80 μm3). Increase in nuclear volume, during G 1 phase of the cell cycle, is apparently a morphological manifestation of change in genomic expression. This key event in preosteoblast differentiation is related to mechanical stress/strain and may be an important rate-limiting step in osteoblast histogenesis.  相似文献   
93.
94.
OBJECTIVE: Regulatory CD4 T cells that express high levels of CD25 play a vital role in the maintenance of tolerance to self antigens and are required for the induction of nonresponsiveness to alloantigens. The long-term CD4+CD25high T-cell reconstitution after allogeneic stem cell transplantation is unknown. Here, we evaluated whether recovery of this T-cell subset might be linked to the establishment of full donor/recipient tolerance. METHODS: The frequency of CD4+CD25high T cells was determined by Fluorescence Activated Cell Sorter (FACS) analysis in 31 patients, with a mean follow-up of more than 31 months posttransplant. The expression levels of Foxp3 mRNA were assessed by quantitative real-time polymerase chain reaction (RT-PCR). RESULTS: Patients with or without graft-versus-host disease (GvHD) had significant and persistent CD4 T-cell lymphopenia. The relative frequency of CD25high cells and the expression levels of FoxP3 mRNA within this subset were similar between all patients and healthy controls. No significant difference was found in the number of Foxp3-expressing CD4+CD25high T cells in patients with or without GvHD. Finally, younger age and absence of previous GvHD were significantly linked to CD4+CD25high T-cell recovery. CONCLUSION: The low number of Foxp3-expressing CD4+CD25high T cells in grafted patients is not a specific default of this compartment but a consequence of global CD4 T-cell lymphopenia after allogeneic stem cell transplantation. Moreover, levels of Foxp3 mRNA in the CD25+ T-cell compartment do not allow predicting the development of GvHD in the long term.  相似文献   
95.
BACKGROUND: The spectrum of alcohol use disorders covers hazardous use, alcohol abuse, and alcohol dependence. The present study evaluated the performance of asialotransferrin, a newly proposed biomarker for alcohol use disorders, in detecting alcohol abuse and alcohol dependence. METHOD: A 4-month trial was conducted in three groups of participants: alcohol abusers and alcohol-dependent patients, as defined in DSM-IV, and a control group. Asialotransferrin was assayed by capillary zone electrophoresis. RESULTS: Asialotransferrin demonstrated a sensitivity of 0.34 and a specificity of 1.00 for alcohol abuse. The sensitivity of asialotransferrin increased to 0.57 in alcohol-dependent patients. CONCLUSION: Despite the high specificity of asialotransferrin in alcohol use disorders, its sensitivity is too low to make it a useful marker of alcohol abuse.  相似文献   
96.
The virucidal and antiviral photoactivities of three compounds, hypericin, tetrabromohypericin and gymnochrome B, were evaluated against dengue viruses. All the three products were active, and both the virucidal and antiviral activities were enhanced by light. Gymnochrome B was more potent than hypericin and tetrabromohypericin. The presence of the side chains on the hypericin core of gymnochromes appears to be beneficial for both virucidal and antiviral activities. This enhanced activity is likely to be linked to a complementary mechanism independent of photoactivation.  相似文献   
97.
BACKGROUND: In newly diagnosed apnoeic patients without a history of hypertension, clinical hypertension is underdiagnosed in at least 40% of the cases. An increase in diastolic blood pressure is the most frequent pattern encountered. OBJECTIVE: To assess clinic and 24-h blood pressure, baroreflex sensitivity and left ventricular mass for identifying the prevalence, the type and the consequences of hypertension in newly diagnosed apnoeic patients. PATIENTS AND METHODS: Fifty-nine unselected patients (age = 48 +/- 12 years, body mass index = 28.1 +/- 4.5 kg/m2) referred to a university hospital sleep laboratory for symptoms suggesting obstructive sleep apnoea were included. Diagnosis of apnoea was accepted when respiratory disturbance index was > or = 15/h of sleep. Blood pressure was considered as normal by their general practitioner and all of them were free of any medication for hypertension. Echocardiography, 24-hour ambulatory blood pressure monitoring and assessment of the baroreflex sensitivity were performed. RESULTS: Forty-two percent of the apnoeic patients demonstrated a clinical hypertension, 34 subjects (58%) had a daytime hypertension, and 45 patients (76%) had a night-time hypertension, using 24-h monitoring. All the daytime hypertensives also had night-time hypertension. Forty-seven of the 59 patients (80%) were hypertensive either in the clinic or using 24-h recording. Diastolic and systolo-diastolic hypertension were the prominent types of hypertension observed both by clinic or ambulatory measurements. Respiratory disturbance index was significantly higher in apnoeic patients suffering isolated diastolic hypertension than in the normotensives (50.9 +/- 26.5/h versus 36.0 +/- 12.3/h, respectively; P = 0.02). The prevalence rate of left ventricular hypertrophy was high (between 15 and 20%) and occurred independently of associated hypertension. Baroreflex sensitivity was altered whatever the type of hypertension and decreased with the severity of obstructive sleep apnoea. CONCLUSION: Hypertension is hugely underdiagnosed in apnoeic patients unknown to be hypertensive. Use of 24-h blood pressure monitoring allowed the diagnosis of twice as much hypertension than did clinical measurement. Even at the beginning of their history of hypertension, apnoeic patients exhibited chronic adaptations of their cardiovascular system, as shown by early changes in baroreflex sensitivity and an increased prevalence of left ventricular hypertrophy.  相似文献   
98.
OBJECTIVE: To evaluate the association between high-risk human papillomavirus (HPV) DNA detection and histological diagnosis in women referred for atypical glandular cells (AGC) or adenocarcinoma in situ (AIS) at Pap smear. METHODS: In this cross-sectional study, 146 women referred for AGC (124), AGC with high-grade squamous intraepithelial lesion (HSIL) (15), or AIS (7) were tested for HPV DNA using Hybrid Capture II (HC II). All women underwent colposcopic examination, and cervical biopsy was performed for 95 patients. Fifty-one women referred due to AGC with normal colposcopy and normal second Pap smear were scheduled for control visits every 4 months. RESULTS: The overall prevalence of HPV DNA was 38%. HPV DNA was detected in 93% of the women with HSIL associated with AGC and in 71% of women with AIS Pap smear, being significantly higher when compared with the prevalence (29%) in women with AGC alone. Forty-five women (30.8%) had clinically significant histological lesions (CIN 2 or worse). High-risk HPV DNA was detected in only 16% of the women without significant abnormalities in biopsy, in contrast to 96% of those who had CIN 2 or CIN 3 and 75% of women with AIS. Eighty-five percent of women with invasive cervical carcinoma (squamous or adenocarcinoma) tested positive for HPV DNA. HPV DNA detection was significantly associated with histological diagnosis of CIN 2 or worse, with an odds ratio (OR) = 51.8 (95% CI 14.3-199.9). CONCLUSION: HPV DNA detection was strongly associated with the severity of cervical lesion (CIN 2 or worse) in women referred for AGC or AIS in their Pap smear. These data implicate the use of HPV testing in triage of women with AGC Pap smears.  相似文献   
99.
BACKGROUND: Monitoring of Epstein-Barr virus (EBV) reactivation after allogeneic hematopoietic stem-cell transplantation markedly improved with quantitative real-time polymerase chain reaction amplification of EBV DNA and visualization of EBV-specific CD8+ T cells with peptide-human leukocyte antigen (HLA) class I tetramers. We decided to combine these methods to evaluate posttransplant EBV reactivation and rituximab therapy. METHODS: We followed 56 patients treated with an HLA-genoidentical sibling (n=32), an HLA-matched unrelated donor (MUD, n=19), or an unrelated cord-blood transplant (n=5). EBV DNA was quantified in plasma and in peripheral blood mononuclear cells (PBMC). Patient CD8+ T cells were stained with a panel of eight tetramers. RESULTS: EBV DNA was detected in half of the patients, mainly in the MUD group (17/19). In 19 patients, viral DNA was detected only in the cellular compartment. All patients who controlled reactivation without rituximab and despite a viral load of greater than 500 genome equivalents (gEq)/150,000 PBMC mounted an EBV-specific CD8+ T-cell response in greater than 1.4% of CD3+CD8+ T cells. Plasmatic EBV genome was found in nine patients preceded by a high cellular viral load. Three of these patients controlled the reactivation before or without the introduction of rituximab, and they all developed a significant and increasing EBV-specific T-cell response. Patients with EBV-specific T cells at the onset of reactivation controlled viral reactivation without rituximab. CONCLUSION: This study emphasizes the benefit of an early and close monitoring of EBV reactivation and CD8+-specific immune responses to initiate rituximab only when necessary and before the immune response becomes overwhelmed by the viral burden.  相似文献   
100.
In this paper the association between smoking history, beverage consumption, diet and bladder cancer incidence is systematically reviewed. A rating system has been used to summarise the level of scientific evidence (i.e. convincing, probable, possible, and no evidence) and the level of association (i.e. substantially increased, (RR2.5), moderately increased (1.5RR<2.5), slightly increased (1.2RR<1.5), no association (0.8RR<1.2), slightly decreased (0.7RR<0.8), moderately decreased (0.4RR<0.7), and substantially decreased (RR<0.4)). There is convincing evidence that cigarette smoking status, frequency and duration substantially increase the risk of bladder cancer. However, the evidence is not clear for other forms of smoking. A small increased risk for cigar, pipe, and environmental smoking is only possible. There is possible evidence that total fluid intake is not associated with bladder cancer. Although there is convincing evidence for a positive association between alcohol consumption and bladder cancer risk in men, the risk is small and not clinically relevant. Coffee and tea consumption are probably not associated with bladder cancer. The authors conclude that total fruit consumption is probably associated with a small decrease in risk. There is probably no association between total vegetable intake, vitamin A intake, vitamin C intake and bladder cancer and a possibly moderate inverse association with vitamin E intake. Folate is possibly not associated with bladder cancer. There probably is a moderate inverse association between selenium intake and bladder cancer risk.  相似文献   
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