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91.
Protein kinase casein kinase 1 (CK1) phosphorylates Ser-45 of beta-catenin, "priming" the subsequent phosphorylation by glycogen synthase-3 of residues 41, 37, and 33. This concerted phosphorylation of beta-catenin signals its degradation and prevents its function in triggering cell division. The sequence around Ser-45 does not conform to the canonical consensus for CK1 substrates, which prescribes either phosphoamino acids or acidic residues in position n-3 from the target serine. However, the beta-catenin sequence downstream from Ser-45 is very similar to a sequence recognized by CK1 in nuclear factor for activated T cells 4. The common features include an SLS motif followed two to five residues downstream by a cluster of acidic residues. Synthetic peptides reproducing residues 38-65 of beta-catenin were assayed with purified rat liver CK1 or recombinant CK1 alpha and CK1 alpha L from zebrafish. The results demonstrate that SLS and acidic cluster motifs are crucial for CK1 recognition. Pro-44 and Pro-52 are also important for efficient phosphorylation. Similar results were obtained with the different isoforms of CK1. Phosphorylation of mutants of full-length recombinant beta-catenin from zebrafish confirmed the importance of the SLS and acidic cluster motifs. A search for proteins with similar motifs yielded, among other proteins, adenomatous polyposis coli, previously found to be phosphorylated by CK1. There is a strong correlation of beta-catenin mutations found in thyroid tumors with the motifs recognized by CK1 in this protein.  相似文献   
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93.
Breast cancer is a rare, but frequently hidden pathology. A woman, 36 years old, during the early months of pregnancy found a little tumor in her right breast. A fine needle biopsy was negative for cancer. Despite this, the tumor rose and two months after delivery (the patient breast-fed her daughter for a month), she had pain in the right axillary region and the tumors involved all superior dials of the right breast. A Madden mastectomy was performed. The histopathological report was: ductal invasive breast cancer 3 of 19 lymph nodes involved, stage IIIA, TNM pT3N2M0, ER -, PgR +--. Chemotherapeutic regimens were: at first ADM 75 mg/m2 for 5 cycles, and after CMF 1-8 for 6 cycles. After six months the woman had a cutaneous recurrence in the scar of mastectomy, treated with surgery and RT. Thirteen months after, she had lung MTS and then brain MTS. The patient died thirty months after the mastectomy. The surgeons have to discover the women high-risk for the breast cancer before and during the pregnancy. Excisional biopsy is the diagnostic procedure of choice for breast lump during pregnancy. When a breast cancer develops during a pregnancy, the surgeon has to operate immediately the tumors. Chemotherapeutic regimens should be delayed until the second o third trimester or after delivery.  相似文献   
94.
There are cases in which resection of cervico-mediastinal goitres requires additional thoracic access as an adjunct to standard transverse cervicotomy, and typically this takes the form of sternotomy or thoracotomy. The authors propose transclavicular access as an alternative to thoracotomy or sternotomy access for the removal of such goitres. This technical variant is performed by means of resection of the middle third of the clavicle and extraperiosteal disarticulation. They report a case of cervicomediastinal or "plunged" goitre associated with mediastinal metastasis from a follicular thyroid carcinoma in a 77-year-old woman, in whom this technical variant was used. They conclude by stressing the greater effectiveness, ease of execution and relatively limited "aggressiveness" of the technique in comparison with other ways of reaching the mediastinum. The variant proves effective in solving a number of technical, functional and aesthetic problems.  相似文献   
95.
Among neurodegenerative diseases, Alzheimer's disease (AD) is a leading cause of death in elderly individuals. AD is characterized, among other clinical findings, by unexplained weight loss, cachexia and altered immune function. To explore whether any relationship between gender and circulating levels of several eating-controlling metabolites exist, we evaluated leptin, tumor necrosis factor (TNF)-alpha, triiodothyronine (T(3)), free (F) thyroxine (T(4)), TSH, PRL, insulin (INS), and cortisol in 15 AD-treated patients (age range 55-82 years): 9 postmenopausal females (without hormone replacement therapy) and 6 males. The results (mean +/- SEM) indicated that circulating leptin levels were significantly (p < 0.05) higher in female AD (40.34 +/- 11.1 ng/ml) than in male AD (6.07 +/- 1.39 ng/ml) patients. The difference found in circulating leptin levels was noticed regardless of BMI (26.75 +/- 1.77 and 24.55 +/- 1.93 kg/m(2), in females and males, respectively) and waist:hip ratios (0.91 +/- 0.03 and 0.94 +/- 0.02, in females and males, respectively). Moreover, serum TNF-alpha concentrations were also significantly (p < 0.02) higher in AD females (12.24 +/- 1.47 pg/ml) than in AD males (6.62 +/- 1.44 pg/ml), regardless of TNF-alpha:BMI ratios (0.50 +/- 0.09 and 0.28 +/- 0.08, in females and males, respectively; p > 0.05). Finally, no differences were observed between gender (in female and male AD patients, respectively) in circulating levels of T(3) (151.33 +/- 9.91 vs. 116 +/- 17.04 ng/dl), FT(4) (1.26 +/- 0.08 vs. 1.24 +/- 0.06 ng/dl), TSH (1.28 +/- 0.16 vs. 2.46 +/- 0.67 microIU/ml), PRL (10.53 +/- 2.47 vs. 12.61 +/- 2.37 ng/ml), INS (11.76 +/- 1.95 vs. 8.59 +/- 1.34 microIU/ml) and cortisol (15.71 +/- 1.23 vs. 12.63 +/- 1.47 microg/dl). These results indicate that our AD group of patients, with normal corticoadrenal and thyroid functions and normoprolactinemia, displayed a gender-related characteristic in the circulating levels of two very important anorectic signals, leptin and TNF-alpha, being both higher in female than in male AD patients, regardless of BMI. Our study suggests that increased circulating levels of both anorexigenic adipokines may contribute to the metabolic changes observed in AD females.  相似文献   
96.
OBJECTIVE: Knowledge of alimentary habits among populations permits a better definition of appropriate public health interventions. We designed the epidemiological project "Ventimiglia di Sicilia" to characterize the risk profile in a rural village with low total cholesterol levels and low early cardiovascular mortality but with a large prevalence of overweight and obesity, which previously have been significantly associated with total mortality. METHODS: 488 individuals of age 20 to 69 years were included in the dietary survey conducted by a seven-day food record. RESULTS: Alimentary habits were characterized by high consumption of total and complex carbohydrates (respectively 52.5 +/- 7.6% and 46.6 +/- 8.2% of daily energy) and by a low cholesterol intake (92.5 +/- 35.0 mg/1000 kcal/day). Fat intake was 34.7 +/- 7.7% of daily energy due to a higher consumption of monounsaturated fats in respect to saturated fats (respectively 20.5 +/- 5.1% and 10.2 +/- 2.9% of daily energy). In particular, in this population there was a large consumption of bread, pasta, fresh vegetables, olive oil and fruits. We also observed an excess of total calories (about 2900 kcal/day in men and 2100 kcal/day in women) not balanced by a high degree of physical activity levels. Furthermore we found a significant higher total and saturated fat consumption in the youngest individuals and in people with higher educational levels. CONCLUSIONS: Dietary habits of Ventimiglia di Sicilia still follow the nutritional characteristics typical of the Mediterranean diet. The high total calorie intake indicates a quantitative more than qualitative problem, which may account the large prevalence of overweight and obesity and may represent a public health issue that needs to be corrected in such a rural population.  相似文献   
97.
The vascular adventitia is activated in a variety of cardiovascular disease states and has recently been shown to be a barrier to nitric oxide bioactivity. Vascular fibroblasts produce substantial amounts of NAD(P)H oxidase-derived reactive oxygen species (ROS) that appear to be involved in fibroblast proliferation, connective tissue deposition, and perhaps vascular tone. However, the physiological and pathophysiological roles of the adventitia have not been extensively studied, possibly because of its location in large blood vessels remote from the vascular endothelium. In recent years, substantial information has been gathered on pathways leading to oxidase activation in smooth muscle cells and fibroblasts and the downstream signaling pathways leading to hypertrophy and proliferation. A clearer understanding of the molecular mechanisms involved will likely lead to therapeutic strategies aimed at preventing vascular dysfunction in diseases such as atherosclerosis, in which these pathways are activated.  相似文献   
98.
99.
Insulin receptors are known to be located on nerve cells in mammalian brain. The binding of insulin to dimerized receptors stimulates specialized transporter proteins that mediate the facilitated influx of glucose. However, neurons possess other mechanisms by which they obtain glucose, including transporters that are not insulin-dependent. Further, insulin receptors are unevenly distributed throughout the brain (with particularly high density in choroid plexus, olfactory bulb and regions of the striatum and cerebral cortex). Such factors imply that insulin, and insulin receptors, might have functions within the central nervous system in addition to those related to the supply of glucose. Indeed, invertebrate insulin-related peptides are synthesized in brain and serve as neurotransmitters or neuromodulators. The present review summarizes the structure, distribution and function of mammalian brain insulin receptors and the possible implications for central nervous system disorders. It is proposed that this is an under-studied subject of investigation.  相似文献   
100.
Glutathione (GSH)-driven lipid peroxidation (LPO) in vitro wascatalyzed by  相似文献   
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