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41.
This study examined the effects of acute and chronic ethanol on cortical somatosensory-evoked potentials (SEPs) of laboratory rats. Evoked potentials were recorded following stimulation of the left hindpaw before and after injection of either saline or ethanol. Animals were then chronically exposed to ethanol in vapor inhalation chambers for five weeks. Recordings of SEPs before and after acute ethanol injection were then obtained 24 h and again seven days after withdrawal from ethanol exposure. The results indicate that acute ethanol produced a dose-dependent reduction in SEP amplitude, but did not alter peak latencies. Chronic ethanol exposure and withdrawal resulted in a significant increase in preinjection baseline response amplitudes when measured at 24 h after withdrawal, but not at seven days, and this treatment did not alter response latency or the effects of acute ethanol administration.  相似文献   
42.
BACKGROUND: Anastomotic stenosis, a common sequela to Roux-en-Y gastric bypass, has a reported incidence of 1.6-27% and recurs in 17-33%. No universal guidelines for optimal treatment exist. The aim of this study was to develop guidelines to treat stenosis that achieve the lowest rate of recurrence while avoiding the complications of excessive dilation. METHODS: This prospective 2-part study enlisted consecutive patients undergoing Roux-en-Y gastric bypass who developed an anastomotic stenosis. In the first part, all patients, regardless of the grade of stenosis, underwent dilation to 12 mm and were followed up for recurrence. In the second part, patients underwent dilation according to the grade of stenosis (12 mm for low, 13.5 mm for medium, 15 mm for high) and were followed up for recurrence. RESULTS: Among 1345 consecutive Roux-en-Y gastric bypass patients, 204 developed an anastomotic stenosis (15.2%). No differences were found in gender, mean age, preoperative body mass index, or weight loss at 1 year. In part 1, the recurrence rate for low-, medium-, and high-grade stenosis was 2.6%, 34.4%, and 35.9%. In part 2, the corresponding rates were 9.7%, 26.3%, and 43.6%. The corresponding mean number of additional dilations per patient with recurrence in part 1 was 1.0, 1.5, and 2.1 and, in part 2, were 1.0, 1.0 and 1.2. CONCLUSION: The results of this study have shown that the stenosis grade can predict the risk of recurrence and determine the optimal balloon size. Definitive treatment was achieved in >90% of patients with low-grade stenosis dilated to 12 mm. Medium- and high-grade stenosis predicted > or =25% recurrence, but increasing the balloon size reduced the number of additional dilations required for patients with recurrence.  相似文献   
43.
Nephrogenic adenoma is an uncommon metaplastic lesion of the lower urinary tract that usually is associated with antecedent inflammation or surgical procedures. We report 10 new cases, 8 of which followed renal transplantation and 1 of which followed partial cystectomy for squamous cell carcinoma of the bladder. No predisposing factors could be identified in 1 patient. The nephrogenic adenomas, all of which were located in the bladder, were treated by either biopsy with fulguration or transurethral resection. The lesion recurred locally in 1 patient.  相似文献   
44.
Rats receiving a single dose of adriamycin (7.5 mg/kg) develop heavy proteinuria and morphological abnormalities similar to those observed in minimal change nephrotic syndrome in humans. A concomitance between enhanced I-a display by resident glomerular macrophages, IL-1-like cytokine secreted by whole isolated rat glomeruli and proteinuria was observed in adriamycin-injected rats during the experimental protocol. In addition, in vitro studies have shown that after stimulation with adriamycin or lipopolysaccharide (LPS) this cytokine is mainly produced by resident glomerular macrophages in culture. Although the precise mechanism of proteinuria in this model needs to be further studied, our results indicate that IL-1-like cytokine could be an important mediator implicated in the structural and functional disturbances occurring at the glomerular capillary wall level in adriamycin nephrosis.  相似文献   
45.
Two new cases of prostatic blue nevus are studied with routine histological, immunohistochemical and ultrastructural methods. Both cases showed a chronic lower urinary tract obstruction due to a benign prostatic hyperplasia with spindle-shaped stromal cells loaded with melanin pigment. These cells were positive for S-100 and negative for HMB-45 antibodies, being, to the best of our knowledge, the first time that this antibody has been tested in prostatic pigmented lesions. The electron-microscopy study was performed in the first case, confirming the nature of these pigmented cells as melanocytes derived from the neural crest showing melanosomes in all the stages of differentiation and without complete basal cell membrane. The histogenesis of pigmented lesions of the prostate and the differences between blue nevus and melanosis are discussed, and the literature is reviewed.  相似文献   
46.
Migraine is a common, disabling disorder associated with considerable personal and societal burden. Current guidelines recommend triptans for the acute treatment of migraine unlikely to respond to less effective therapies. Rizatriptan is a second-generation triptan available in tablet or orally disintegrating tablet (wafer) formulations that offers several advantages over other members of its class. Rizatriptan is rapidly absorbed from the gastrointestinal tract and achieves maximum plasma concentrations more quickly than other triptans, providing rapid pain relief. Clinical trials have shown that rizatriptan is at least as effective or superior to other oral migraine-specific agents in the acute treatment of migraine, and has more consistent long-term efficacy across multiple migraine attacks. Rizatriptan has a favorable tolerability profile, and patients have reported greater satisfaction and a preference for rizatriptan over other migraine-specific agents. Improvements in quality of life reported with rizatriptan are consistent with its favorable efficacy and tolerability profiles. Notably, multi-attribute decision models that combine clinical data with patient- and physician-reported treatment preferences have identified rizatriptan as one of three triptans closest to a hypothetical “ideal”. The efficacy and tolerability of rizatriptan for the acute treatment of migraine have thus been well established.  相似文献   
47.
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema.  相似文献   
48.
Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is frustrating for both clinicians and patients. The prostate is not scientifically proven to cause the symptoms of CP/CPPS, yet the prostate continues to be the diagnosis of convenience in this complex syndrome in men. However, if the pain is not of prostatic origin, what causes it? A heterogeneous group of insults can result in a common neurogenic pain response, resulting in recurring pain and voiding or sexual dysfunction. To add to this dilemma, certain life-threatening diagnoses, such as carcinoma-in-situ, are in the differential diagnosis and must be excluded. Urodynamics may be useful in evaluating and treating patients whose voiding symptoms predominate, such as those with concomitant overactive bladder symptoms. However, many patients with CP/CPPS will not have measurable abnormalities by conventional methods and likely suffer from a functional somatic syndrome that is best treated with a multimodality approach.  相似文献   
49.
50.
Participation of human epididymal sperm coating antigens in fertilization   总被引:1,自引:0,他引:1  
A polyclonal antiserum directed against human sperm coating proteins of epididymal origin (anti-KCl) was tested for its ability to alter sperm function. Spermatozoa from normal ejaculates were selected by swim-up separation and capacitated by overnight incubation at room temperature. Exposure of these cells to anti-KCl (0.39 mg protein/ml), prior to their use in the hamster ova penetration test, reduced the penetration of denuded oocytes by 65% (P less than 0.005). Significant inhibitions of lesser magnitude were observed at lower serum concentrations (to 0.098 mg/ml). In an effort to understand the mechanism of this inhibition, other sperm function parameters thought to be related to oocyte penetration were studied. The inhibitory effect was exerted without noticeable changes in sperm motility (determined by the percentage of motile cells and their linear velocity), and in the absence of major sperm agglutination. Anti-KCl did not inhibit the occurrence of spontaneous or induced (by human follicular fluid) acrosome reaction in capacitated spermatozoa. In contrast, exposure to anti-KCl reduced the ability of capacitated spermatozoa to bind tightly to the hamster oolemma. None of these effects were elicited by a control preparation obtained from pre-immune rabbit sera. Exposure of zona-free oocytes to the antiserum did not alter their penetrability by normal sperm. These results suggest that the antigens recognized by anti-KCl participate in some specific step of the sperm-ovum interaction.  相似文献   
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