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71.
Unusual Metastatic Spread of Follicular Thyroid Carcinoma: Report of a Case   总被引:1,自引:0,他引:1  
Concurrent skull and liver metastases from follicular thyroid carcinoma is a very rare event. We herein present the case of a 72-year-old woman who initially presented with a swelling in the right supraorbital region that proved to be metastasis from a well-differentiated follicular thyroid carcinoma of clear-cell type. The metastatic workup disclosed a huge liver metastasis and an additional metastasis in the left iliac fossa. The treatment of this patient included a total thyroidectomy, an excision of the skull lesion, and the administration of radioiodine therapy, as well as thyroid-stimulating hormone (TSH) suppression therapy. However, the course of her disease was relentless. Although well-differentiated thyroid carcinoma tends to show an excellent course, the presence of metastatic disease leads to a very dismal prognosis.An erratum to this article can be found at  相似文献   
72.
In this phase of structure-affinity relationship study of VL-0395, a new anthranilic acid based CCK1 selective antagonist, we propose a series of unnatural aminoacidic derivatives. The result of this work is the identification of a new CCK ligand, which possesses an affinity (IC50 = 35 nm) one order of magnitude greater than the lead and, as a general rule, it points out how the hypothesized receptorial pocket which accommodates the Phe residue allows much more structural modification than that interacting with the N-terminal group. Hence, the modification of the C-terminal pharmacophoric group of our lead VL-0395 can not only enhance the affinity of anthranilic acid derivatives but can modulate the selectivity for one CCK receptor subtype or afford mixed antagonists.  相似文献   
73.
In this study, the expression of cyclins D1 and D3, as well as cyclin-dependent kinase inhibitor p27 in thymic epithelial tumors (thymomas) is examined. Histological specimens from 24 patients (11 males and 13 females) were submitted to classification according to WHO criteria. Staining for cyclins D1, D3 and p27 was applied and evaluation was performed for expression of D1, D3 and p27. Eighteen patients presented low-grade thymomas (nine B1, predominantly cortical; three B2, cortical; six B3, well-differentiated thymic carcinoma) and six patients benign thymomas (four A-medullary, two AB-mixed). The p27 expression in patients with benign thymomas was 42+/-26%, whereas in patients with low-grade thymoma, it was 11+/-13%. The expression of cyclins D1 and D3 was 2.8+/-2.7 and 10+/-6% for benign as well as 8.3+/-9.6 and 12+/-10% for low-grade thymomas, respectively. A statistically significant difference was revealed regarding the p27 expression through different grades (analysis of variance P-value 0.00076) and histopathological types of thymomas (P=0.0047). This finding of greater p27 expression in benign thymomas with progressive reduction in higher grades is compatible with observations on other soft tissue and solid tumors suggesting that p27 level decreases during tumor development and progression.  相似文献   
74.
In most Balkan countries, with the exception of Greece, transplantation is very rare and equality of access does not exist. In 2003, a Balkan partnership was established called SETNET (South-Eastern European Transplantation Network) for the promotion of transplantation. The objectives are to bring about the diffusion of transplantation techniques and practices in the Balkans, to increase public support for and participation in transplantation, and to eliminate the disparities in access to good health-care. SETNET is already beginning to generate data for an analysis of transplantation-related needs in the Balkans and to accelerate cross-border data exchange in transplantation-related emergencies. In the next few years, a regional training programme will be introduced for all health-care staff involved in transplantation. A regional organ procurement and transplantation network will be set up to utilize the existing telemedicine infrastructure. If successful, it will also prove that telemedicine infrastructures, however modest, can be the backbone for other, far-reaching human networks.  相似文献   
75.
BRAF mutations result in constitutively active BRAF kinase activity and increased extracellular signal-regulated kinase (ERK) signaling and cell proliferation. Initial studies have shown that BRAF mutations occur at a high frequency in melanocytic nevi and metastatic lesions, but recent data have revealed much lower incidence of these mutations in early-stage melanoma, implying that other factors may contribute to melanoma pathogenesis in a wild-type (WT) BRAF context. To identify such contributing factors, we used microarray gene expression profiling to screen for differences in gene expression between a panel of melanocytic and melanoma cell lines with WT BRAF and a group of melanoma cell lines with the V599E BRAF mutation. We found that SPRY2, an inhibitor homologous to SPRY4, which was previously shown to suppress Ras/ERK signaling via direct binding to Raf-1, had reduced expression in WT BRAF cells. Using small interfering RNA-mediated SPRY2 knockdown, we showed that SPRY2 acts as an inhibitor of ERK signaling in melanocytes and WT BRAF melanoma cells, but not in cell lines with the V599E mutation. We also show that SPRY2 and SPRY4 directly bind WT BRAF but not the V599E and other exon 15 BRAF mutants. These data suggest that SPRY2, an inhibitor of ERK signaling, may be bypassed in melanoma cells either by down-regulation of its expression in WT BRAF cells, or by the presence of the BRAF mutation.  相似文献   
76.
77.
Purpose To investigate the pharmacokinetics of polyethylene glycol-coated liposomal doxorubicin (PLD, Caelyx) when given as a single agent and in combination with the taxanes paclitaxel or docetaxel in humans.Methods The plasma kinetics of PLD were studied in 19 cancer patients treated with PLD every 4 weeks combined with either paclitaxel (on a weekly basis in seven and as a single infusion in three patients) or docetaxel (weekly in seven and as a single infusion in two). Plasma concentrations of PLD were quantified in two sets of samples per patient to compare the same pharmacokinetic parameters in each subject when treated with single-agent PLD and again with the combination. Total doxorubicin concentrations in plasma were quantified by HPLC. Pharmacokinetics were evaluated by noncompartmental analysis and the data obtained were compared for differences by a matched-pairs nonparametric test.Results Coadministration of paclitaxel produced a median/mean 54/80% increase in PLD AUCinf (95% confidence interval 23% to 136%, P=0.002). The observed increase was consistent among all subjects. PLD clearance was also decelerated in the presence of paclitaxel (P=0.013) while other pharmacokinetic parameters were affected modestly. A small increase in the AUC of PLD was observed in the docetaxel/PLD arm (mean increase 12%, P=0.039) while PLD clearance decreased marginally and other pharmacokinetic parameters remained unaffected. AUC extrapolated to infinity was below 8% in both arms.Conclusions This study showed the presence of a pharmacokinetic interaction that led to higher plasma concentrations of PLD when combined with paclitaxel and to a minor extent when combined with docetaxel. This pharmacokinetic information may be of value when planning combination therapies of PLD with taxanes.  相似文献   
78.
Progression of progenitor cells towards neuronal differentiation is tightly linked with cell cycle control and the switch from proliferative to neuron-generating divisions. We have previously shown that the neuronal protein BM88 drives neuroblastoma cells towards exit from the cell cycle and differentiation into a neuronal phenotype in vitro. Here, we explored the role of BM88 during neuronal birth, cell cycle exit and the initiation of differentiation in vivo. By double- and triple-labelling with the S-phase marker BrdU or the late G2 and M-phase marker cyclin B1, antibodies to BM88 and markers of the neuronal or glial cell lineages, we demonstrate that in the rodent forebrain, BM88 is expressed in multipotential progenitor cells before terminal mitosis and in their neuronal progeny during the neurogenic interval, as well as in the adult. Further, we defined at E16 a cohort of proliferative progenitors that exit S phase in synchrony, and by following their fate for 24 h we show that BM88 is associated with the dynamics of neuron-generating divisions. Expression of BM88 was also evident in cycling cortical radial glial cells, which constitute the main neurogenic population in the cerebral cortex. In agreement, BM88 expression was markedly reduced and restricted to a smaller percentage of cells in the cerebral cortex of the Small eye mutant mice, which lack functional Pax6 and exhibit severe neurogenesis defects. Our data show an interesting correlation between BM88 expression and the progression of progenitor cells towards neuronal differentiation during the neurogenic interval.  相似文献   
79.
We evaluated the predictive value of several parameters, including the International Staging System (ISS) for myeloma, in patients with advanced disease treated with thalidomide-based regimens (TBR). We analyzed 119 patients, from 3 phase II studies. Patients with pretreatment beta2 microglobulin<3.5 mg/l and albumin 3.5 g/dl were scored ISS stage 1, patients with beta2 microglobulin<3.5 mg/l and albumin<3.5 g/dl or beta2 microglobulin 3.5-5.5 mg/l regardless of albumin levels were scored ISS stage 2, patients with beta2 microglobulin>5.5 mg/l ISS stage 3. ISS stage was 1, 2 and 3 in 45, 32 and 23% of patients respectively. Seventy-four patients (62%) achieved at least partial response. Median progression-free and overall survival were 8 months and 19.5 months respectively. ISS stage, serum LDH and performance status were independent predictive factors for survival. Based on these 3 variables a scoring system was developed with survival times of 38.1, 28.8 and 5.8 months for scores 0, 1 and 2 respectively. The ISS staging system was highly predictive for overall survival of patients with advanced myeloma treated with TBR. With the addition of performance status and serum LDH, a simple scoring system was developed which may help select patients likely to benefit from TBR.  相似文献   
80.
OBJECTIVES: To determine the impact of adenotonsillectomy on quality of life (QOL) in children with obstructive sleep disorders (OSDs) before and after surgery. DESIGN: Prospective, observational, before-and-after trial. SETTING: Seven tertiary pediatric otolaryngology practices. PATIENTS: Convenience sample of 101 children (mean age, 6.2 years) with adenotonsillar hypertrophy and OSD scheduled for adenotonsillectomy. INTERVENTION: Adenotonsillectomy was performed in children for OSDs. Quality of life was assessed using the Obstructive Sleep Disorders-6 survey, a validated instrument for detecting QOL change in children with OSDs. Surveys were completed at the initial office visit (visit 1), the day of surgery (visit 2), and at the postoperative office visit (visit 3). Physical characteristics were assessed using tonsillar and orocraniofacial scales (visit 1). Satisfaction with health care decisions was assessed using the Satisfaction With Decision and Satisfaction With Office Visit scales (visit 1). MAIN OUTCOME MEASURES: Short-term changes in QOL before (visits 1 and 2) and after (visits 2 and 3) surgery. RESULTS: Changes in QOL before surgery were trivial or small, and smaller than changes after surgery (mean change score, 0.18 vs 2.3; P<.001). Large, moderate, and small improvements in QOL were seen in 74.5%, 6.1%, and 7.1% of children, respectively. Sleep disturbance, caregiver concern, and physical suffering were the most improved domains, although significant changes also occurred for speech and swallowing problems, emotional disturbance, and activity limitations. Five percent of children had poorer QOL after surgery, but no predictive factors were identified. CONCLUSION: Adenotonsillectomy produces large improvements in at least short-term QOL in most children with OSDs.  相似文献   
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