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61.
IntroductionBreast cancer survivors are at increased risk of developing unrelated primary cancers, particularly lung cancer. Evidence indicates that sex hormones as well as a deregulation of DNA-repair pathways may contribute to lung cancer onset. We investigated whether the hormone status and expression of markers involved in DNA repair (BRCA1/2, ERCC1, and P53R2), synthesis (TS and RRM1), and cell division (TUBB3) might be linked to lung cancer risk.Patients and MethodsThirty-seven breast cancer survivors with unrelated lung cancer and 84 control subjects comprising women with breast cancer (42/84) or lung cancer (42/84) were enrolled. Immunohistochemistry on tumor tissue was performed. Geometric mean ratio was used to assess the association of marker levels with patient groups.ResultsEstrogen receptor was expressed in approximately 90% of the breast cancer group but was negative in the majority of the lung cancer group, a result similar to the lung cancer control group. Likewise, ER isoform β was weakly expressed in the lung cancer group. Protein analysis of breast cancer versus control had a significantly lower expression of BRCA1, P53R2, and TUBB3. Likewise, a BRCA1 reduction was observed in the lung cancer group concomitant with a BRCA2 increase. Furthermore, BRCA2 and TUBB3 increased in ipsilateral lung cancer in women who had previously received radiotherapy for breast cancer.ConclusionThe decrease of DNA-repair proteins in breast cancer could make these women more susceptible to therapy-related cancer. The increase of BRCA2 and TUBB3 in lung cancer from patients who previously received radiotherapy for breast cancer might reflect a tissue response to exposure to ionizing radiation.  相似文献   
62.
BACKGROUND: There is a broad need to improve physician continuing medical education (CME) in the management of intimate partner violence (IPV). However, there are only a few examples of successful IPV CME programs, and none of these are suitable for widespread distribution. DESIGN: Randomized controlled trial beginning in September 2003 and ending in November 2004. Data were analyzed in 2005. SETTING/PARTICIPANTS: Fifty-two primary care physicians in small (fewer than eight physicians), community-based medical offices in Arizona and Missouri. INTERVENTION: Twenty-three physicians completed a minimum of 4 hours of an asynchronous, multi-media, interactive, case-based, online CME program that provided them flexibility in constructing their educational experience ("constructivism"). Control physicians received no CME. MAIN OUTCOME MEASURES: Scores on a standardized self-reported survey, composed of ten scales of IPV knowledge, attitudes, beliefs, and self-reported behaviors (KABB) administered before randomization and repeated at 6 and 12 months following the CME program. RESULTS: Use of the online CME program was associated with a significant improvement in eight of ten KABB outcomes, including physician self-efficacy and reported IPV management practices, over the study period. These measures did not improve in the control group. CONCLUSIONS: The Internet-based CME program was clearly effective in improving long-term individual educational outcomes, including self-reported IPV practices. This type of CME may be an effective and less costly alternative to live IPV training sessions and workshops.  相似文献   
63.
Uveal melanoma develops in one of the most capillary-rich tissues of the body and is disseminated hematogenously. Knowledge of the nature and the spatiotemporal expression of angiogenic factors in uveal melanoma is essential to the development of new treatment strategies, especially with regard to improving survival. In this study, we measured the angiogenic potential of several angiogenic factors in different uveal melanoma cell lines, in an in vivo model, and in primary tumor material from patients with melanoma. Most uveal melanoma cell lines expressed vascular endothelial growth factor (VEGF)-A (isoforms 121, 165, 189), VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF) to various extents. The expression of VEGF-A 121 was always higher than that of the other VEGF-A isoforms, suggesting that VEGF-A 121 is the most abundant VEGF-A isoform. All experimentally induced tumors expressed VEGF-A, VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF). Similarly, significant amounts of mRNA for VEGF-B, VEGF-C, VEGF-D, and b-FGF were detected in uveal melanoma material from patients. In contrast, VEGF-A mRNA (121, 165, 189) was low (9/28) or not detectable in the tumor samples. The synthesis of VEGF-A 165 and b-FGF protein by various cell lines was measured by enzyme-linked immunosorbent assay (ELISA). Most uveal melanoma cell lines, but not normal melanocytes, strongly synthesized and secreted VEGF-A 165 and b-FGF during cell culture. Our data suggest that the expression of (lymph) angiogenic factors may play a causal role in the angiogenesis and progression of uveal melanoma and distant metastasis.  相似文献   
64.
Summary The potencies of several muscarine receptor antagonists in blocking either the autoinhibition of acetylcholine release or the muscarinic contraction of the sphincter muscle upon acetylcholine release were investigated in the guinea-pig iris. The agonist at pre- or postjunctional muscarine receptors was acetylcholine released upon field stimulation (5.5 Hz, 2 min) of the irides preloaded with 14C-choline. The stimulation-evoked 14C-overflow was doubled in the presence of atropine 0.1 mol/l but unaffected by the agonist (±)-methacholine (50 mol/l). Thus, under the present stimulation conditions, the autoinhibition of acetylcholine release on the guinea-pig iris cholinergic nerves was nearly maximally activated. Isotonic contractions of the irides upon field stimulation consisted of a rapid, atropine (0.1 mol/l). peak phase followed by a sustained contraction which involved a cholinergic and a non-cholinergic stimulation of the sphincter muscle. The M2-selective antagonists methoctramine (10 mol/l) and gallamine (100 µmol/l). increased both the 14Goverflow and the peak contractions evoked by field stimulation. In contrast, the M3-selective antagonist hexahydrosiladifenidol (0.1–10 mol/l) failed to affect the evoked 14C-release but concentration-dependently (1–10 mol/l) reduced the iris contractions. Pirenzepine (10 mol/l) enhanced the evoked 14C-overflow and inhibited the peak contractions (0.1–10 mol/l; maximal effect at 10 mol/l). The low potency of the antagonist at both receptor sites indicates that an M1 muscarine receptor is not involved. The results are consistent with the idea of M2 muscarine receptors mediating autoinhibition of acetylcholine release in the guinea-pig iris and M3-like receptors inducing the contraction of the sphincter muscle. Send offprint requests to I. T. Bognar at the above address  相似文献   
65.
66.
δ-subunit containing extrasynaptic GABAA receptors are potential targets for modifying neuronal activity in a range of brain disorders. With the aim of gaining more insight in synaptic and extrasynaptic inhibition, we used a new positive modulator, AA29504, of δ-subunit containing GABAA receptors in mouse neurons in vitro and in vivo. Whole-cell patch-clamp recordings were carried out in the dentate gyrus in mouse brain slices. In granule cells, AA29504 (1 μM) caused a 4.2-fold potentiation of a tonic current induced by THIP (1 μM), while interneurons showed a potentiation of 2.6-fold. Moreover, AA29504 (1 μM) increased the amplitude and prolonged the decay of miniature inhibitory postsynaptic currents (mIPSCs) in granule cells, and this effect was abolished by Zn2+ (15 μM). AA29504 (1 μM) also induced a small tonic current (12.7 ± 3.2 pA) per se, and when evaluated in a nominally GABA-free environment using Ca2+ imaging in cultured neurons, AA29504 showed GABAA receptor agonism in the absence of agonist. Finally, AA29504 exerted dose-dependent stress-reducing and anxiolytic effects in mice in vivo. We propose that AA29504 potentiates δ-containing GABAA receptors to enhance tonic inhibition, and possibly recruits perisynaptic δ-containing receptors to participate in synaptic phasic inhibition in dentate gyrus.  相似文献   
67.
Medulloblastoma (MB) represents approximately 4% of adult brain tumours, and as such is a poorly studied disease. Although many adult MB are treated using paediatric MB protocols, the reported outcomes are inferior to those observed in children. It remains unclear whether biologic differences underlie these clinical observations. We investigated the molecular characteristics of 31 adult MB. Twelve and 19 adult MB were respectively examined using Affymetrix-HG-U133-plus-2.0-genechips and immunohistochemical analyses. 26/31 (84%) of adult MB examined by gene expression and/or immunohistochemical analysis showed evidence of sonic hedgehog (SHH) pathway activation. A comparison of adult and paediatric MB showed that most adult tumours cluster within the SHH-active subgroup of paediatric MB. The preponderance of SHH activity in adult MB tumours was also shown by positive SFRP1 immunostaining in 16/19 adult paraffin-embedded adult MB tumour blocks. A smaller proportion of adult tumours exhibited evidence of WNT pathway activation, as confirmed by nuclear β-catenin staining (9.7%; 3/31). Notably, we found PTCH1 gene mutation in 4/8 samples tested. Similar to children, adult MB has abnormalities in developmental signalling pathways including SHH and WNT. Importantly, we found a preponderance of SHH pathway activation amongst MB tumours in adults. This SHH signature does not appear to correlate with a long-term favourable outcome. Differences in molecular profiles exist between adult and paediatric SHH-driven MB and further investigations are needed to better characterize age-related molecular profiles in this subgroup.  相似文献   
68.
INTRODUCTION: Refractory sprue is characterised by distinctive morphologic alterations and the emergence of clonal intraepithelial lymphocytes. Aim: In this case report the authors emphasize the importance of histopathology in the diagnosis of refractory sprue. METHODS: The sequential biopsies from this patient have been investigated with routine histology, immunohistochemistry and molecular genetics for T-cell clonality analysis. RESULTS: The severely cachectic patient presenting with malabsorption syndrome has been diagnosed with celiac disease through a duodenal biopsy, and the CD8 negativity of the intraepithelial lymphocytes suggested the possible diagnosis of refractory sprue. Azathioprine and glucocorticoid therapy was administered due to the failed jejunal feeding and gluten-free diet, resulting in clinically complete, morphologically partial remission. Intestinal T-cell lymphoma developed in the ileocecal region within two years after the first clinical presentation. DISCUSSION: Refractory sprue and the enteropathy-type T-cell lymphoma constitute a disease spectrum. The reported case shows how a simple method can provide crucial information in the diagnosis of refractory sprue.  相似文献   
69.
Purpose: The aim of this study was to analyse the factors associated with caesarean section (CS) at the Department of Obstetrics and Gynaecology, University of Szeged, Hungary.

Study design: Data collection was based on self-administered questionnaire and medical records related to the deliveries in the year of 2014. Maternal age, education level, marital status, pre-gestational body mass index (BMI), infertility treatment, previous CS, gestational diabetes mellitus (GDM), pre-pregnancy hypertension and pregnancy-induced hypertension (HT/PIH) were examined. The participation rate was 67.3%, multiple pregnancies and questionnaires with missing data were excluded (n?=?1493). Univariate and multivariate comparisons were performed.

Results: There were 1125 (45.4%) CSs out of 2479 deliveries. CS rate: 40.0%. Underweight 109 (7.1%), normal 921 (60.2%), overweight 320 (20.9%) obese 181 (11.8%). HT/PIH: 7.6% (n?=?117), GDM: 10.1% (n?=?155). The odds of CS were significantly higher among obese mothers (OR: 1.81) compared with the normal weight group. Increasing maternal age (OR: 0.97) and being underweight (OR: 0.59) significantly decreased, previous CS (OR: 12.19), infertility treatment (OR: 1.91) and HT/PIH (OR: 1.87) significantly increased the probability of CS.

Conclusions: Pre-gestational obesity, infertility treatment, previous CS and HT/PIH had significant effect on the mode of delivery.  相似文献   
70.
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