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991.
We explored the relationship between the cytogenetic/biologic characteristics of B-chronic lymphocytic leukemia (B-CLL) cells and their tendency to undergo spontaneous or fludarabine-induced apoptosis in vitro. B cells from 36 B-CLL patients were incubated with or without fludarabine for 48 h. Apoptosis was determined by two assays: annexin V staining and DNA staining. Fluorescence in situ hybridization was used for detection of trisomy 12, 11q deletion, and 17p deletion. Bcl-2 and CD38 expressions were determined by flow cytometry. Five patients had 17p deletion, 6 had trisomy 12, and another 6 had 11q deletion. B-CLL cells with 17p deletion had significant resistance to apoptosis induced by fludarabine and a slight spontaneous resistance to apoptosis. Bcl-2 and CD38 were not associated with in vitro spontaneous and fludarabine-induced apoptosis. In conclusion, 17p deletion, which causes loss of p53 gene, is associated with resistance to fludarabine-induced apoptosis in vitro. New treatment modalities should be tried in B-CLL patients with 17p deletion.  相似文献   
992.
Last decade, there have been important improvements about tuberculosis (Tbc) in the world. Today, 32% of world populations are infected by Tbc basil's, every year about 9 million people have been catching Tbc. We have purposed to determine the incidence of Tbc and the factors affect it, using rate of bacteriology in diagnosis, rate of treatment completion and to constitute an idea for innovation. Diyarbakir, standard monthly data forms used for informing of Tbc in tuberculosis control dispensary are investigated retrospectively among 1996-2004. The mean incidence of yearly Tbc is 37.77/100.000 and pulmonary Tbc is 30.11/100.000. In this period have been determined 3724 new Tbc patient; 2969 (79.7%) are pulmonary Tbc and 755 (20.3%) extrapulmonary Tbc. 842 patient (22.6%) of pulmonary Tbc are smear positive. Tbc pleurisy is the most common type of extrapulmonary Tbc in our series. 3354 (90.1%) of whole patients and 2624 (88.4%) with pulmonary Tbc had completed treatment. There is no data about the rate of cure. This is the most common problem Tbc control system. In 2005, cure rates will have been determined by the way of new form. 162 (4.4%) patient had abandoned treatment. Incidence of Tbc is higher than the incidence of Turkey. It was considered that at the first place highly growing population, the crowded family pattern sharing the same house and bad socioeconomic factors have been playing a major role. Furthermore, it was found that the rate of bacteriological diagnosis was low. In order to increasing of this rates should be carried out necessary studies, should be tried to diagnose all patients with bacteriological methods. End of the treatment cure should be tried to demonstrate by way of examination of sputum. The treatment process should be pursued by directly observed treatment strategy.  相似文献   
993.
CONTEXT: Fetal supply of maternally derived fatty acids requires lipase-mediated hydrolysis of lipoprotein-borne triglycerides and phospholipids at the placental surface. OBJECTIVE: The objective of the study was to test the hypothesis that members of the triglyceride lipase gene (TLG) family are expressed in the human placenta at the maternoplacental (syncytiotrophoblast) and fetoplacental (endothelial cells) interface and that their expression is altered in pregnancy pathologies. DESIGN AND SETTING: Expression of TLG family members in primary placental cells (trophoblast and endothelial cells) and tissues of first-trimester and term human placenta was analyzed by microarrays, RT-PCR, Western blotting, and immunohistochemistry. Their expression was compared between normal pregnancies and those complicated with intrauterine growth restriction (IUGR). PARTICIPANTS: Participants included women with uncomplicated pregnancies and pregnancies complicated by IUGR. RESULTS: Endothelial lipase (EL) and lipoprotein lipase (LPL) were the only lipases among the TLG family expressed in key cells of the human placenta. In first trimester, EL and LPL were expressed in trophoblasts. At term, EL was detected in trophoblasts and endothelial cells, whereas LPL was absent in these cells. Both lipases were found at placental blood vessels, EL in vascular endothelial cells and LPL in the surrounding smooth muscle cells. In total placental tissue EL expression prevails in first trimester and at term. Compared with normal placentas, EL mRNA was decreased (30%; P < 0.02), whereas LPL mRNA expression was increased (2.4-fold; P < 0.015) in IUGR. CONCLUSION: EL is the predominant TLG family member in the human placenta present at both interfaces. EL and LPL are dysregulated in IUGR.  相似文献   
994.
CONTEXT: Uterine leiomyomata are common tumors that cause irregular uterine bleeding and pregnancy loss and depend on estrogen for growth. Aromatase catalyzes the conversion of androgens to estrogens. Aromatase expression is regulated via alternatively used promoters in the placenta (I.1 and I.2a), fat (I.4, I.3, and II), bone (I.6), and gonads (II). A prostaglandin E(2)/cAMP-dependent pathway regulates coordinately the proximal promoters I.3/II, whereas glucocorticoids and cytokines regulate the distal promoter I.4. Use of each promoter gives rise to a population of aromatase mRNA species with unique 5'-untranslated regions (5'-UTRs). Uterine leiomyoma tissue, but not normal myometrium, overexpresses aromatase leading to estrogen-stimulated cell proliferation. Aromatase inhibitor treatment shrank uterine leiomyomata in a few women. OBJECTIVE AND DESIGN: Promoter I.4 was reported to regulate aromatase expression in uterine leiomyomata from a group of Japanese women. Here, we used two independent techniques to identify the promoters that regulate aromatase expression in uterine leiomyomata (n = 30) from 23 African-American, Hispanic, and white women. RESULTS: Rapid amplification of 5'-cDNA ends of aromatase mRNA species revealed the following distribution of promoter usage in leiomyomata: promoters I.3/II, 61.5%; I.2a, 15.4%; I.6, 15.4%; and I.4, 7.7%. Real-time PCR, which quantifies mRNA species with promoter-specific 5'-UTRs, revealed the following distribution for each 5'-UTR as a fraction of total aromatase mRNA: I.3/II, 69.6%; I.4, 7.3%; and other promoters, 23.1%. CONCLUSIONS: The primary in vivo aromatase promoter in leiomyoma tissues in non-Asian U.S. women is the prostaglandin E(2)/cAMP-responsive I.3/II region. Alternative signals may stimulate aromatase expression that is a common biological phenotype in uterine leiomyomata.  相似文献   
995.
Our objective was to develop a bioadhesive vaginal tablet formulation of ornidazole by using different polymer mixtures, to evaluate the bioadhesive tablet properties, and to investigate the irritation potential of the formulations to the rat vaginal tissue. Vaginal tablets of ornidazole were directly compressed with bioadhesive and swellable polymer mixtures as release-controlled agents. Carbopol 934 (Cp), pectin (Pc), hydroxypropylmethylcellulose (HPMC), sodium carboxymethylcellulose (Na CMC), and guar gum (GG) were used in different ratios. Bioadhesive properties, swelling capacity, release studies, and histological studies of the formulations were carried out. The bioadhesive strength between bovine vagina and surface of the tablets was determined by tensile experiments, and it was found to be dependent on Cp content. The release mechanism was described and found to be non-Fickian for all formulations. Dissolution data were evaluated statistically. No histological damage was found except one formulation containing high amount of guar gum.  相似文献   
996.
The new mefenamic acid-alginate bead formulation prepared by ionotropic gelation method using 3 × 22 factorial design has shown adequate controlled release properties in vitro. In the present study, the irritation effects of mefenamic acid (MA), a prominent non-steroidal anti-inflammatory (NSAI) drug, were evaluated on rat gastric and duodenal mucosa when suspended in 0.5% (w/v) sodiumcarboxymethylcellulose (NaCMC) solution and loaded in alginate beads. Wistar albino rats weighing 200 ± 50 g were used during in vivo animal studies. In this work, biodegradable controlled release MA beads and free MA were evaluated according to the degree of gastric or duodenal damage following oral administration in rats. The gastric and duodenal mucosa was examined for any haemorrhagic changes. Formulation code A10 showing both Case II transport and zero order drug release and t50 % value of 5.22 h was chosen for in vivo animal studies. For in vivo trials, free MA (100 mgkg?1), blank and MA (100 mgkg?1) loaded alginate beads (formulation code A10) were suspended in 0.5% (w/v) NaCMC solution and each group was given to six rats orally by gavage. NaCMC solution was used as a control in experimental studies. In vivo data showed that the administration of MA in alginate beads prevented the gastric lesions.  相似文献   
997.

Introduction  

The benefits of higher positive end expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) have been modest, but few studies have fully tested the "open-lung hypothesis". This hypothesis states that most of the collapsed lung tissue observed in ARDS can be reversed at an acceptable clinical cost, potentially resulting in better lung protection, but requiring more intensive maneuvers. The short-/middle-term efficacy of a maximum recruitment strategy (MRS) was recently described in a small physiological study. The present study extends those results, describing a case-series of non-selected patients with early, severe ARDS submitted to MRS and followed until hospital discharge or death.  相似文献   
998.
999.
1000.
We investigated the presence of anti-neutrophil cytoplasmic antibodies (ANCA) in the serum and bronchoalveolar lavage fluid (BALF) of 21 cystic fibrosis (CF), 7 idiopathic bronchiectasis (IBR), and 11 control children and the relation between ANCA and any bacteria grown in BALF. Six of the CFs, but none of the IBRs or controls had positive serum cytoplasmic or perinuclear-ANCA (c-ANCA, p-ANCA). Serum autoantibodies against bactericidal/permeability increasing protein (BPI-ANCA) were positive in 2 CFs, 1 IBR and 1 control. While none of the CFs, IBRs or controls had positive BALF (c- or p-ANCA), 1 CF, 1 IBR and none of the controls had positive BALF BPI-ANCA. Pseudomonas aeruginosa was not grown in the specimens of any of the subjects. As the number of the patients in our study was very limited, further longitudinal and well-designed studies are necessary to show whether or not the presence of ANCA in serum or BALF relates to the presence of P. aeruginosa infection in the airways of CF and IBR patients.  相似文献   
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