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Eclampsia is characterized by generalized convulsions in pregnant women with hypertension and proteinuria. Little is known about what triggers the convulsions in this syndrome. The prevailing view is that convulsions are caused by cerebral vasospasm and cerebral edema. However, many important clinical findings argue against cerebral edema or hypertensive encephalopathy as the sole causes of convulsions in eclampsia. The utero-placental ischemia causes the release of certain molecules such as neurokinin B, inflammatory cytokines, endothelins, and tissue plasminogen activator. These molecules stimulate excitatory neuronal receptors and alter neuronal excitability, synaptic transmission, and neuronal survival independent of any vascular effects. Highlighting the neuromodulatory and the convulsive effects of each of these molecules which are elevated in pre-eclampsia, offers a new perspective on the mechanisms of convulsions in eclampsia.  相似文献   
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Familial adenomatous polyposis (FAP) is an autosomal dominant disorder which typically presents with colorectal cancer in early adult life, secondary to extensive adenomatous polyps of the colon. In addition to the colonic manifestations, the syndrome presents several extracolonic features including, congenital hypertrophy of the retinal pigment, osteomata and desmoid tumors. In this study, we aimed to investigate the clinical and genetic features in a Tunisian family with FAP. Sequence of the APC gene (Adenomatous Polyposis Coli) revealed a novel mutation (c.2016-2017 del TA) in exon 15, present in all affected individuals in an heterozygous state. The frameshift mutation generates a premature stop codon at amino acid 677 of the APC protein (p. H672Qfs X5). The unaffected family members did not harbor this mutation, however, a first degree relative of the patient aged of 32 year-old was phenotypically normal but carries the c.2016-2017 del TA mutation. This discrepancy can be explained by the effect of modifier gene which can affect the expressivity of the disease.  相似文献   
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BackgroundThe standard treatment for women with endometrial cancer is total abdominal hysterectomy and pelvic lymphadenectomy for surgical staging. Total laparoscopic radical hysterectomy (TLH) is an alternative approach providing surgical and patient related advantages to laparoscopy.MethodsTwenty female patients with early stage endometrial cancer were operated upon by TLH and pelvic lymphadenectomy, aiming to assess the safety and efficacy of TLH.ResultsThe mean operative time was 296.8 min conversion to laparotomy was done in one patient due to bleeding from the uterine vessels. The mean blood loss was 517.5 cc. The uterus was removed transvaginally in 18 patients (90%) and via a small Pfannenstiel incision in two patients (10%). The mean number of pelvic lymph nodes retrieval was 21.2. Postoperative bleeding occurred in one patient (5%) which necessitated exploration. One patient (5%) suffered a pulmonary embolism. Four patients (20%) developed pyrexia, and one patient (5%) suffered from a chest infection. One patient (5%) had wound infection. The mean hospital stay was 4.5 days (range 3–10).ConclusionTLH with pelvic lymphadenectomy is a safe and effective approach in the treatment of early endometrial carcinoma.  相似文献   
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AbouZid S  Orihara Y 《Planta medica》2007,73(12):1327-1329
Thiophene A and thiophene A diol are the major polyacetylenes isolated from the hairy roots of Ambrosia maritima (Asteraceae) cultured under continuous light irradiation. The biosynthesis of thiophene A was studied using [1-(13)C]-, [2-(13)C]-, [1,2-(13)C]-acetates. The biosynthesis of thiarubrine A, produced by hairy roots cultured in the dark, was studied using [1,2-(13)C]-acetates and [18-(13)C]-linoleic acid. Our results suggest a catabolic pathway for polyacetylenes biosynthesis from linoleic acid in hairy roots of Ambrosia maritima.  相似文献   
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This work proposes an alternative green and selective biocatalytic route for Glycerin Monostearate (α-monostearin) production. The conventional method of production uses an elevated temperature. Apart from the high energy consumption, such high temperatures darken the final product's color, lead to random reactions, and produce high orders of diglycerides and triglycerides instead of monoglycerides. The proposed production process was performed by esterifying stearic acid with glycerin in an organic medium using Candida antarctica lipase (Novozym 435) at a mild temperature. The reaction conditions were optimized using the response surface methodology (RSM): optimum conditions were a temperature of 60 °C, glycerin to stearic acid molar ratio of 8:1, and Novozym 435 amount of 6% w/w. The solvent addition remarkably improved the α-monostearin yield to nearly 80% without the need for the energy-intensive distillation step. The conventional autocatalytic esterification (AUT) process was also performed to investigate the comparative monoglyceride yield, and it was found to be 22.5%. Proton nuclear magnetic resonance and gas-chromatography confirmed that α-monostearin could be produced with the highest purity using the proposed enzymatic method (ENZ). Economic and environmental analyses were also conducted for the proposed ENZ process, and the results were compared with those of the AUT process. The total capital investment of α-monostearin production, considering a projected capacity of 4950 t year?1 and 11% interest for the proposed ENZ process, was favorably 2.5 times lower than that of the AUT process, suggesting a promising investment opportunity. However, the total production costs showed unfavorable negative net present value (NPV) and return on investment (ROI) for the ENZ process and favorable positive NPV and ROI for the AUT process, indicating that the proposed venture is not profitable for α-monostearin production. However, the process can be profitable at improved operational stability of Novozym 435 up to 1 kg per 3-ton product. The carbon footprint was calculated on the basis of the given capacity and conditions of 50 and 656 t CO2 eq./year for the ENZ and AUT processes, respectively. The synthesis of α-monostearin using the proposed route can be considered a building block toward a cleaner large-scale production of α-monoglycerides.  相似文献   
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OBJECTIVE: The aim of this work was to focus on the development and validation of the use of topical fluorescein in the intraoperative localization of cerebrospinal fluid (CSF) fistulas, and to screen its use in preoperative diagnosis of CSF rhinorrhea as well as postoperative detection of a recurrence. MATERIALS AND METHODS: Twenty-five patients with CSF rhinorrhea were treated with an endoscopic endonasal technique. Topical intranasal 5% fluorescein was used for preoperative diagnosis and intraoperative localization of the site of the leak. A change in the color of the fluorescein from yellow to green fluorescence and sometimes streaming the fluorescein over the nasal mucosa and blood denoted the presence of CSF, and the site of the leak could be traced. RESULTS: The cause of the leak was accidental trauma in 11 patients, spontaneous in 9 patients, and iatrogenic in 5 patients. The ethmoidal roof was the most common site of leak (52%) followed by the cribriform plate (40%) and then the sphenoid sinus (8%). We have achieved 100% success rate in sealing the CSF fistulas in our 25 patients with no recurrence detected during the follow-up period (mean, 19+/-10 months). The preoperative use of fluorescein-soaked cotton pledgets was 100% accurate in diagnosing CSF rhinorrhea when compared with B2 transferrin testing. The intraoperative use of topical intranasal fluorescein was also 100% accurate in locating the site of the CSF fistula when compared with the surgical findings. No major complications have been reported. CONCLUSION: In the presence of a clinically diagnosed CSF leakage, topical fluorescein is a very easy, sensitive, safe, and highly accurate tool in the intraoperative localization of the site and extent of CSF fistulas, and should be considered a viable noninvasive alternative to intrathecal fluorescein. We also recommend its use as a simple and quick outpatient clinic test for preoperative diagnosis of CSF rhinorrhea. It can be used postoperatively as well when there is a doubt of recurrence of the CSF leak.  相似文献   
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