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21.
Due to its objective nature, auditory brainstem response (ABR) evoked by complex stimuli has been gaining attention lately. The present study aimed to compare the speech-evoked auditory brainstem response (speech-ABR) results between two ethnic groups: Malay and Chinese. In addition, it was also of interest to compare the speech-ABR outcomes obtained from the present study with the published Caucasian data. Thirty healthy male adults (15 Malay and 15 Chinese) were enrolled in this comparative study. Speech syllable/da/presented at 80 dBnHL was used to record speech-ABR waveforms from the right ear of each subject. Amplitudes and latencies of speech-ABR peaks (V, A, C, D, E, F and O), as well as composite onset measures (V/A duration, V/A amplitude and V/A slope) were computed and analyzed. When the two ethnic groups were compared, all speech-ABR results were not statistically different from each other (p > 0.05). When the data from the present study were compared with the published Caucasian data, most of the statistical analyses were significant (p < 0.05). That is, Asian subjects revealed significantly higher peak amplitudes, earlier peak latencies, higher V/A amplitudes and steeper V/A slopes than that of Caucasians. The speech-ABR results between Malay and Chinese were found to be essentially similar due to anatomical similarities. Nevertheless, specific normative data for Asian adults are required as their speech-ABR results are different from that of Caucasian males. This issue should be addressed before it can be applied holistically in multiracial countries.  相似文献   
22.
Papillary fibroelastoma is a rare primary tumor of the heart valves. This lesion can occur on any of the valves or endothelial surface of the heart and has been detected by echocardiography, by cardiac catheterization, during open heart operations for other conditions, and at autopsy. Because of the potential for comorbidities, this tumor should be removed. We present the case of an elderly man with a diagnosis of severe mitral valve regurgitation and moderate tricuspid valve regurgitation who was suspected to have a tricuspid valve vegetation. Mitral valve replacement, tricuspid valve repair, and excision of the lesion were performed successfully. A histologic examination of the vegetation confirmed it to be a papillary fibroelastoma. We present this case to emphasize the rarity of this tumor and the importance of a correct diagnosis to avoid delaying its prompt and definitive management.  相似文献   
23.
Kazui T  Yamashita K  Washiyama N  Terada H  Bashar AH  Suzuki T  Ohkura K 《The Annals of thoracic surgery》2002,74(5):S1806-9; discussion S1825-32
BACKGROUND: To evaluate the safety and usefulness of antegrade selective cerebral perfusion (SCP) during arch aneurysm or aortic dissection operations. METHODS: Between January 1986 and December 2001, 330 patients underwent aortic arch repair using SCP. Operations were performed with the aid of hypothermic extracorporeal circulation, SCP, and systemic circulatory arrest in most cases. In all, 89 patients (27%) were operated on for acute aortic dissection, 77 (23%) for chronic aortic dissection, and 164 (50%) for degenerative aneurysm. Total arch replacement using a branched graft was performed in 288 patients (94%). Mean SCP time was 86.2 +/- 28.5 minutes. RESULTS: The overall in-hospital mortality rate was 11.2% (falling to 3.2% in the 124 patients operated on between 1997 and 2001). Independent determinants of hospital mortality were pump time, renal/mesenteric ischemia, chronic renal failure, increasing age, period of operation, and nonuse of four-branched arch graft. The overall postoperative incidences of temporary and permanent neurologic dysfunction were 4.2% and 2.4%, respectively. There was no significant correlation between SCP time and in-hospital mortality or neurologic outcome. CONCLUSIONS: Selective cerebral perfusion is a reliable technique for cerebral protection and it facilitates complex and time-consuming total arch replacement.  相似文献   
24.
Thirty-eight patients with mammary gland tuberculosis were evaluated over a 5-year period presenting to the surgical unit of our institution. Unilateral involvement of the breast in a woman presenting at an average age of 29 years was the commonest observation. A lump in the breast with or without discharging sinuses was the most common clinical presentation. Ten (26%) of these patients had breast pain with or without increased breast nodularity. Axillary lymph nodal involvement was evident in 14 (36%) of our patients. Only five patients had associated pulmonary tuberculosis, the rest having an isolated involvement of the breast. Fine-needle aspiration cytology was the most reliable diagnostic modality. Medical therapy with antitubercular drugs ranging from 6 to 9 months was the mainstay of treatment. Surgical intervention was reserved for selected refractory cases.  相似文献   
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Introduction and Hypothesis

The objective of this study was to identify the predictors of postoperative voiding dysfunction in women following extensive vaginal pelvic reconstructive surgery.

Methods

We enrolled 1,425 women who had pelvic organ prolapse of POP-Q stage III or IV and had undergone vaginal pelvic reconstructive surgery with or without transvaginal mesh insertion from January 2006 to December 2014. All subjects were required to complete a 72-h voiding diary, and the IIQ-7, UDI-6, POPDI-6 and PISQ-12 questionnaires. Urodynamic study was performed preoperatively and postoperatively.

Results

Of the 1,425 women, 54 were excluded due to incomplete data, and 1,017 of the remaining 1,371 (74.2 %) had transvaginal mesh surgery and 247 (18 %) had concurrent midurethral sling insertion. Of 380 women (27.7 %) with preoperative voiding dysfunction, 37 (9.7 %) continued to have voiding dysfunction postoperatively. Of the remaining 991 women (72.3 %) with normal preoperative voiding function, 11 (1.1 %) developed de novo voiding dysfunction postoperatively. The overall incidence of postoperative voiding dysfunction was 3.5 % (48/1,371). Those with concurrent midurethral sling insertion were at higher risk of developing voiding dysfunction postoperatively (OR 3.12, 95 % CI 1.79?–?5.46, p?<?0.001). Diabetes mellitus, preoperative detrusor pressure at maximal flow (Dmax) <10 cm H2O and postvoid residual volume ≥200 ml were significant risk factors for the development of postoperative voiding dysfunction (OR 3.07, 1.84 and 2.15, respectively; 95 % CI 1.69?–?5.60, 1.39?–?2.91 and 1.10?–?3.21, respectively).

Conclusions

Diabetes mellitus, concurrent midurethral sling insertion, preoperative Dmax <10 cm H2O and postvoid residual volume ≥200 ml in patients with advanced pelvic organ prolapse were risk factors for the development of postoperative voiding dysfunction after vaginal pelvic reconstructive surgery. Therefore, counseling is worthwhile before considering vaginal pelvic reconstructive surgery.
  相似文献   
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Objective:To determine the lead bioactive compound in kernel extract of Mangifera pajang and its anti-cancer activity against human breast cancer cell lines with positive estrogen receptor(MCF-7).Methods:The methanolic extract of dried powder kernel of Mangifera pajang was exposed to column chromatography for isolation.The structural elucidation of the isolated compound was characterized using infrared,nuclear magnetic resonance,mass spectrometry.Furthermore,cytotoxicity,morphological changes,flow cytometry and cell cycle arrest analyses were performed to examine the mechanism of anti-proliferation and apoptosis induced by methyl gallate against MCF-7.Results:One compound was isolated from the methanolic extract of Mangifera pajang kernel and identified as methyl gallate.The flow cytometric results demonstrated induction of apoptosis in MCF-7 cells by three concentrations of methyl gallate.The cell cycle arrest showed a significant(P<0.05)decrease in cell progression at G2/M phase of MCF-7 after treatment with 100μM of methyl gallate.The cell percentage of early and late apoptosis was significant at 10 and 100μM of methyl gallate.Also,methyl gallate treatment induced up-regulation of reactive oxygen species levels in MCF-7 cells with a reduction in superoxide dismutase levels.Conclusions:These findings indicate that isolated methyl gallate from Mangifera pajang kernel extracts induces growth inhibition and apoptosis in MCF-7 cells via up-regulating oxidative stress pathway.  相似文献   
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The retinoblastoma tumor suppressor protein pRb restricts cell growth through inhibition of cell cycle progression. Increasing evidence suggests that pRb also promotes differentiation, but the mechanisms are poorly understood, and the key question remains as to how differentiation in tumor cells can be enhanced in order to diminish their aggressive potential. Previously, we identified the histone demethylase KDM5A (lysine [K]-specific demethylase 5A), which demethylates histone H3 on Lys4 (H3K4), as a pRB-interacting protein counteracting pRB''s role in promoting differentiation. Here we show that loss of Kdm5a restores differentiation through increasing mitochondrial respiration. This metabolic effect is both necessary and sufficient to induce the expression of a network of cell type-specific signaling and structural genes. Importantly, the regulatory functions of pRB in the cell cycle and differentiation are distinct because although restoring differentiation requires intact mitochondrial function, it does not necessitate cell cycle exit. Cells lacking Rb1 exhibit defective mitochondria and decreased oxygen consumption. Kdm5a is a direct repressor of metabolic regulatory genes, thus explaining the compensatory role of Kdm5a deletion in restoring mitochondrial function and differentiation. Significantly, activation of mitochondrial function by the mitochondrial biogenesis regulator Pgc-1α (peroxisome proliferator-activated receptor γ-coactivator 1α; also called PPARGC1A) a coactivator of the Kdm5a target genes, is sufficient to override the differentiation block. Overexpression of Pgc-1α, like KDM5A deletion, inhibits cell growth in RB-negative human cancer cell lines. The rescue of differentiation by loss of KDM5A or by activation of mitochondrial biogenesis reveals the switch to oxidative phosphorylation as an essential step in restoring differentiation and a less aggressive cancer phenotype.  相似文献   
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