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41.
AIMS: To study the effect of a conditioning stimulus on an external urethral sphincter (EUS)contraction evoked by a magnetic stimulation at different time intervals. METHODS: Seven healthy male volunteers underwent EUS pressure measurement. At baseline, magnetic stimulation of the lumbosacral spinal cord above the motor threshold was performed and evoked EUS pressure responses were recorded. The lumbosacral magnetic stimulation was repeated with same intensity, while a selective electrical dorsal penile nerve stimulation below the bulbocavernosus reflex (BCR) threshold was preceding at five different intervals (10, 20, 30, 50, 100 msec). The protocol was performed with empty and full bladder (BLA), and baseline responses were statistically compared to those with combined stimulation. RESULTS: When the dorsal penile nerve electrical stimulation preceded the lumbosacral magnetic stimulation by 20 msec (P=0.0048), 50 msec (P=0.0039), or 100 msec (P=0.0002), the amplitudes of the EUS pressure response with empty BLA were significantly reduced compared to lumbosacral magnetic stimulation alone. With a filled BLA, the amplitudes of the EUS were significantly reduced only at an interval of 50 msec (P<0.0001). CONCLUSIONS: A conditional sensory pudendal stimulation seems to have the capacity to inhibit the external urethral sphincter contraction induced by a magnetic stimulation. The inhibitory effect seems to depend on the latency between the peripheral and lumbosacral stimulation as well as on the degree of BLA filling. It remains to be proved if the neuromodulative effect of the conditional stimulus occurs at a spinal or supraspinal level.  相似文献   
42.
PURPOSE: The problem of late relapse of testicular germ cell tumor (GCT) is poorly understood. No more than approximately 300 cases have been reported to date. It appears that late relapse (L/R) of GCT involves a more aggressive biology than virginal GCT. In the present study we increased the understanding of L/R by analyzing these events in a large patient sample. MATERIALS AND METHODS: Late relapse was defined as recurrence of disease more than 2 years after completion of primary treatment. A total of 122 patients (50 with pure seminoma and 72 with nonseminoma) were retrospectively studied. Several parameters were analyzed including age, clinical stage, treatment at primary presentation, occurrence of prior early relapse, interval to L/R, tumor markers, site of relapse, and mode and outcome of L/R treatment. Possible effects of various clinical parameters on treatment results were studied by multivariate statistical analysis. RESULTS: Median age at first presentation was 34 years and 26.5 years in patients with seminoma and nonseminoma, respectively. The intervals to L/R were 42 months (range 25 to 276) in seminoma and 64.5 months (range 28 to 216) in nonseminoma. A total of 75% of nonseminomas but only 20% of seminomas had disseminated disease at first presentation, while 51 patients with nonseminoma had initially received chemotherapy. alpha-Fetoprotein was increased in 45 patients (of 59 eligible) with nonseminoma at L/R, human chorionic gonadotropin in 12 cases. alpha-Fetoprotein levels greater than 100 U/l indicated poor prognosis. Topographically relapses were mainly confined to lymph nodes of the abdomen, chest and neck. Of 72 patients with nonseminoma cure failed in 37 in contrast to only 6 patients with seminoma (of 48 eligible). Inclusion of surgery increased the chance of cure (RR 4.0, 95% confidence interval 0.9-18.5). CONCLUSIONS: Late relapses of GCT are biologically and clinically distinct from virginal GCT. These events occur in nonseminoma and seminoma, but clinical features are quite different in the 2 groups. Increase of alpha-fetoprotein is typical in late relapsing nonseminoma and levels of more than 100 U/l appear to indicate poor prognosis. Anatomically L/R presents as lymphadenopathy of abdomen, chest or neck. Treatment should include surgery in nonseminoma. Seminomas and otherwise chemotherapy naive cases might respond to chemotherapy only. Particular risk groups for late relapse are nonseminoma with prior early relapse, patients receiving chemotherapy for disseminated disease at first presentation and those with pure teratoma. These latter subgroups should be followed with annual health examinations for at least 10 years.  相似文献   
43.
TGF-beta1 as a marker of delayed fracture healing   总被引:4,自引:0,他引:4  
Mitogens of the TGF-beta superfamily have been shown to be crucial local and systemic regulatory molecules involved in fracture healing. However, there exists only little information about systemic regulation of bone regeneration by growth factors and no reports comparing serum levels of bone growth factors between normal and failed fracture healing have been published so far. We hypothesized that quality of fracture healing might be reflected by systemic alterations of key regulatory growth factors involved in bone formation and remodeling. Therefore, the aim of this study was to evaluate possible differences in serum levels of BMP-2, BMP-4, and TGF-beta1 in patients with normal and delayed fracture healing. 103 patients with diaphyseal fractures of long bones were recruited prospectively. Peripheral blood samples were collected over a period of 6 months following a standardized time schedule. At the end of the individual investigation period, growth factor serum levels were measured using commercially available enzyme immunoassays. For the elimination of disturbing influences, patients in both groups were matched by gender, age, fracture type, and localization as well as applied technique of osteosynthesis. During a study period of 1 year, 10 patients with an atrophic type of delayed union could be retrieved and matched to 10 patients with normal fracture healing. The diagnosis of delayed union was assumed in case of failed consolidation 4 months after trauma. We found an increase of TGF-beta1 serum levels up to 2 weeks after fracture in both groups with a following return to the reference value within 6 weeks after trauma. However, decline of serum concentration occurred earlier in patients with delayed fracture healing. At 4 weeks after trauma, serum levels of TGF-beta1 were significantly lower in patients of the delayed union group. Serum levels of BMP-2 and BMP-4 were below detection level in all patients, respectively. These findings support the critical role of TGF-beta1 in fracture healing. Events during the consolidation phase seem to be dependent on sufficient availability of TGF-beta1.  相似文献   
44.
We have examined serial sera from 17 juvenile patients with nasopharyngeal carcinoma (NPC) for their capacity to neutralize the activity of Epstein-Barr virus (EBV)-specific DNase. The results revealed that NPC patients who became long-term survivors (LTS) without evidence of the disease either never possessed significant levels of antibodies to the enzyme or showed a gradual decline in the number of EBV DNase units neutralized from an elevated level at diagnosis to an insignificant figure several years later. All the 10 LTS neutralized less than 4, and some neutralized less than 2 units of the enzyme 3 or more years after the initial diagnosis. In contrast, serial sera from juvenile patients who died of NPC neutralized over 10 and as many as 25 units of EBV DNase either persistently until death occurred or with transient declines during unmaintained remissions. Rises and declines in the neutralizing activity were, with few exceptions, accompanied by corresponding changes in the titers of IgA and IgG antibodies to EB viral capsid antigen and to the diffuse component of the early antigens. Although the number of juvenile NPC cases available for study was small, the observations suggest that the EBV DNase neutralization test may serve to provide information on the prognosis of the patients.  相似文献   
45.
The Epstein-Barr virus (EBV)-specific leukocyte migration inhibition (LMI) reaction was used to detect EBV antigens in human tumor biopsies in parallel with nuclei acid hybridization for EBV DNA. None of six EBV DNA-negative tumors gave any significant LMI reaction. Fourteen of 17 EBV DNA-positive tumors gave a significant difference between the migration of leukocytes from EBV-seropositive versus -seronegative donors. One tumor gave a borderline reaction. The two-LMI-negatives in this group had only a marginal EBV DNA content. It is suggested that the EBV-specific LMI test may be useful for detecting EBV genomes in tissue and tumor extracts.  相似文献   
46.
47.
Body experience of 34 patients was investigated two years after the end of treatment with Concentrative Movement Therapy (KBT) in an in-patient integrative psychotherapy. Change in body experience at the end of treatment and after the two year period was compared to symptomatic strain and the amount of interpersonal problems. Body experience was rather restricted in the beginning of treatment. The improvement of body experience during treatment showed to be stable after two years, as did the symptomatic strain. Interpersonal problems were not reduced as much during treatment but in the follow-up period. Patients with benefit from KBT treatment through a better approach to their body, felt more bodily self-confident at the end of treatment. They also had less feelings of insecurity and apprehension concerning their body than those who could profit little from KBT. In both groups a reduction of symptomatic strain was found. Patients with little profit from KBT had higher symptomatic and interpersonal strain and more feelings of insecurity concerning their body in the beginning of the treatment. Their improvement at the time of follow-up was low. Results are discussed regarding the relevance of different elements of integrative in-patient therapy and the possibility of differential indications for body-oriented psychotherapy.  相似文献   
48.
PURPOSE: To compare keratocyte loss in the corneal stroma after laser-assisted subepithelial keratectomy (LASEK) and photorefractive keratectomy (PRK) in rabbits. SETTING: Department of Ophthalmology, University of Essen, Essen, and the Institute of Anatomy, University of Bochum, Bochum, Germany. METHODS: Laser-assisted subepithelial keratectomy and PRK were performed in rabbits and studied 1, 3, 10, and 20 days after surgery. Excimer photoablation was done unilaterally with a 6.0 mm ablation zone and an 80 microm depth, equivalent to -6.0 diopters. Keratocyte death was analyzed using DNA fragmentation-detecting terminal deoxynucleotidyl transferase deoxy-UTR-nick end labeling (TUNEL) assay and transmission electron microscopy. RESULTS: Numerous TUNEL-positive keratocytes occurred 1 day after PRK; the number decreased significantly after 3 days. After LASEK, significantly fewer TUNEL-positive keratocytes were noted at the early time points (P<.001 at 1 day; P< or =.05 at 3 days). At 10 days, the number of TUNEL-positive keratocytes decreased in both groups but remained significantly higher after PRK than after LASEK (P<.001). Twenty days after both procedures, no significant signs of keratocyte death were found in the corneal stroma. Transmission electron microscopy revealed few apoptotic keratocytes after LASEK. After PRK, apoptotic keratocytes, characterized by chromatin condensation, apoptotic bodies, and cell shrinkage, were scattered in the stroma. The ultrastructural findings confirmed the results obtained with the TUNEL assay. CONCLUSIONS: Laser-assisted subepithelial keratectomy induced significantly less apoptotic keratocyte death than PRK and promoted wound healing in the acute phase after photoablation. This procedure may offer the possibility of treating higher myopia with a decreased risk for developing wound healing-related complications known to occur after PRK.  相似文献   
49.
Panic disorder is an anxiety disorder with an estimated heritability of up to 48%. Pharmacological and genetic studies suggest that genes coding for proteins involved in the catecholaminergic system might be relevant for the pathogenesis of the disease. In the present study, we genotyped a single nucleotide polymorphism (472G/A=V158M) in the coding region of the catechol-O-methyl-transferase (COMT) gene in 115 patients with panic disorder and age- and sex-matched controls. Association analysis revealed a significant excess of the more active COMT allele (472G=V158) in patients with panic disorder (p=0.04), particularly in female patients (p=0.01), but not in male patients (p=1.0). The assessment of a possible interaction of the COMT polymorphism with a previously reported functional 30-bp VNTR in the monoamine oxidase A promoter (MAOALPR) in female patients did not yield significant results. Our data support a role of the 472G/A (V158M) COMT polymorphism or a nearby locus in the pathogenesis of panic disorder in women.  相似文献   
50.
Helicobacter pylori colonizes the stomach of almost half the world population and is a causative agent of gastric carcinomas and duodenal ulcers. Only a small fraction of infected people will develop these severe illnesses and a predictive test to identify people at high risk would greatly benefit disease management. Our study aimed to identify conserved bacterial antigens that may be useful for the development of such a diagnostic test. High-resolution immunoproteomics by 2-dimensional electrophoresis of H. pylori 26695 proteins was carried out with sera from infected patients with either duodenal ulcer (n=30) or gastric carcinoma (n=30), 2 clinically divergent conditions. According to their antigen recognition patterns clear groups of patients were identified. Although this classification did not correspond to the clinical status, it may be correlated to other bacterial or host factors that influence the outcome of infection. In general antigen recognition patterns were found to be highly variable, however by utilizing powerful image analysis and statistical tests the recognition of 14 antigenic protein species was found to differ significantly (p<0.01) between both diseases. Particular protein species of GroEL, HyuA, GroES and AtpA appear to be useful surrogate markers for gastric carcinoma detection and consequently should be considered for further prospective studies to assess their predictive value. For one protein species of AtpA, evidence was found that different post-translational modifications may confer different immunogenicities.  相似文献   
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