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81.
The aim of the research was to show our diagnostic and therapeutic experience with antiphospholipid syndrome (APS) in pregnant women. 36 pregnant women suspect on APS were included in the study: 32 with primary antiphospholipd syndrome (PAPS) and 4 with secondary antiphospholipid syndrome (SAPS). All pregnant women received low-molecular-weight-heparin (LMWH) and low dose aspirin (LDA) therapy. Control group represented 26 women with SAPS and previous bad reproductive anamnesis. Average pregnancy lasted 37.06 +/- 0.707 weeks. LMWH and LDA therapy was successful in 97.22%. Lupus anticoagulant (LA) was found to be more frequent in PAPS group (71.87%). Anticardiolipin antibodies (aCL) were found to be more frequent in SAPS (26.66%). For three patients (3.37%), PAPS was diagnosed due to a fact that they had positive antibeta2-glycoproteinl (antibeta-GP1). To make APS diagnosis, it is of great importance to search for all antiphospholipid antibodies. LMWH and low dose of acetylsalicylic acid should be the first choice therapy.  相似文献   
82.
Little information is available regarding distribution of HPV types in different histological subtypes of adenocarcinoma (AC). Thus, in this study we examined the frequency of high-risk (hr) HPV types in AC, adenocarcinoma in situ (AIS) and adenosquamous carcinoma (ADSQ). A total of 102 cases of primary cervical adenocarcinoma (26 AIS and 76 invasive AC) obtained from pathology files from 1995-2006 were histologically subtyped. Our results demonstrated that endocervical type occupied the major subtype of AC (22/66) followed by ADSQ (17/66) where as in the group of AIS endocervical type (12/23) was followed by intestinal type of AIS (7/23). Successful DNA extraction was obtained in 89 samples; 81 out of 89 (91.0%) tested positive for HPV DNA. The prevalence of HPV DNA in AIS, AC and ADSQ was 91.3% (21/23), 90.9% (60/66) and 94.1% (16/17), respectively. We found HPV 18 type to be the most predominant type in AIS (11/21) and AC (17/60) followed by HPVof undeternmined type in AIS (3/21) and HPV 16 in AC (9/60) as the sole viral type. HPV 18 was most frequently detected type in all histological subtypes of AIS and AC. We have detected HPV DNA in all 5 samples of clear cell carcinoma (CCC), although other studies have reported a highly variable prevalence of HPVDNA in CCC. The most prevalent HPV type in ADSQ was HPV-16 followed by HPV 33 as single type. The observed overall predominance of HPV 18 in AIS (chi(2) = 6.109, p< or = 0.025) and AC (chi(2) = 8.927, p< or =0.01) as well as of HPV 16 in ADSQ (chi(2) = 10.164, p < or = 0.01) was statistically significant. Our data revealed statistically significant predominance of single hrHPV infections in AIS (16/21; chi(2) = 11.523, p < 0.001) and AC (37/60; X2 = 6.533, p < 0.025) whereas multiple hrHPV infections were more abundant in AC comparing to AIS (23/81and 5/81, respectively; chi(2) = 13.989, p< or =0.001).  相似文献   
83.
Melanoma patients are subject to different degrees of psychosocial distress. The emotional impact of malignant melanoma can be long lasting and profound, with the most common reactions to melanoma being depression, anxiety and deterioration in quality of life. Coping styles have been shown to have a significant influence on patients' quality of life and their emotional reaction to the illness. The aim of this paper was to investigate the quality of life, emotional status and coping styles in patients with melanoma. 31 patients suffering from malignant melanoma were included in the study. Results of this study show that melanoma has a medium influence on patients' psychological status and quality of life. The most "constructive" coping style--problem focused coping is the mostly used style by the patients, which might be one of the reasons why the illness didn't have a more severe influence on patients' psychological status.  相似文献   
84.
The aim of this research was to assess the clinical and biochemical efficacy of the octreotide in the treatment of patients with various functional gastroenteropancreatic neuroendocrine tumors (GEP-NETs). The study included 14 patients treated with octreotide for 6 months. They were diagnosed with VIPoma, glucagonoma, gastrinoma, medullary thyroid carcinoma (solitary and as a part of MEN-II syndrome), pancreatic carcinoids (solitary and as a part of multiple endocrine neoplasia type-1 syndrome-MEN-1 syndrome) and midgut carcinoids. The patients presented with Verner-Morrison, glucagonoma, Zollinger Ellison and carcinoid syndrome respectively. All had a metastatic disease at the time of diagnosis and a positive octreoscan finding. Initially elevated chromogranin A (CgA) levels were detected in 11 (78.6%) and elevated 5-hydroxyindolacetic acid (5-HIAA) levels in 8 (57.1%) patients. Symptomatic efficacy assessments were made by diarrhea reductions during treatment course, and laboratory efficacy was assessed through changes in 5-HIAA and CgA levels. Assessments were made initially and following 6 months of therapy. Median urinary 5-HIAA and the number of stools decreased significantly (p = 0.016 and p = 0.009 respectively, p < 0.05) while CgA levels had the decreasing tendency but not statistically significant (p = 0.14). There was a positive correlation between the 5-HIAA reduction and the decrease in stool number at baseline and during treatment course (p < 0.05). No correlation was observed between 5-HIAA and CgA levels and also there was no correlation between CgA reduction and symptomatic improvement. The results prove octreotide to be effective in reducing symptoms and biochemical markers associated with hypersecretory syndromes of GEP-NETs.  相似文献   
85.
The aim of this prospective study was to determine the prevalence and localization of stenotic atherosclerotic lesions of supra-aortic arteries in diabetic patients according to age and sex. Angiograms obtained by digital subtraction angiography were analyzed in 150 diabetic patients (study group) and 150 non-diabetic patients (control group) with symptoms of cerebral ischemia. Diabetic patients were found to have a significantly higher prevalence of stenotic atherosclerotic lesions of the internal carotid artery. Lesions of the large supra-aortic arteries were significantly more common in the left than in the right side of the neck (p < 0.001), but the difference between the diabetic and the non-diabetic group did not reach statistical significance. Hemodynamic conditions were found to be more important than diabetes for the occurrence of atherosclerotic lesions in these arteries. Changes in the proximal segment of the left common carotid artery were the most common finding in diabetic patients, hence attention should be paid to this localization on control examinations.  相似文献   
86.
Cerebral hyperammonemia is a hallmark of hepatic encephalopathy, a debilitating condition arising secondary to liver disease. Pyruvate oxidation including tricarboxylic acid (TCA) cycle metabolism has been suggested to be inhibited by hyperammonemia at the pyruvate and -ketoglutarate dehydrogenase steps. Catabolism of the branched-chain amino acid isoleucine provides both acetyl-CoA and succinyl-CoA, thus by-passing both the pyruvate dehydrogenase and the -ketoglutarate dehydrogenase steps. Potentially, this will enable the TCA cycle to work in the face of ammonium-induced inhibition. In addition, this will provide the -ketoglutarate carbon skeleton for glutamate and glutamine synthesis by glutamate dehydrogenase and glutamine synthetase (astrocytes only), respectively, both reactions fixing ammonium. Cultured cerebellar neurons (primarily glutamatergic) or astrocytes were incubated in the presence of either [U-13C]glucose (2.5 mM) and isoleucine (1 mM) or [U-13C]isoleucine and glucose. Cell cultures were treated with an acute ammonium chloride load of 2 (astrocytes) or 5 mM (neurons and astrocytes) and incorporation of 13C-label into glutamate, aspartate, glutamine and alanine was determined employing mass spectrometry. Labeling from [U-13C]glucose in glutamate and aspartate increased as a result of ammonium-treatment in both neurons and astrocytes, suggesting that the TCA cycle was not inhibited. Labeling in alanine increased in neurons but not in astrocytes, indicating elevated glycolysis in neurons. For both neurons and astrocytes, labeling from [U-13C]isoleucine entered glutamate and aspartate albeit to a lower extent than from [U-13C]glucose. Labeling in glutamate and aspartate from [U-13C]isoleucine was decreased by ammonium treatment in neurons but not in astrocytes, the former probably reflecting increased metabolism of unlabeled glucose. In astrocytes, ammonia treatment resulted in glutamine production and release to the medium, partially supported by catabolism of [U-13C]isoleucine. In conclusion, i) neuronal and astrocytic TCA cycle metabolism was not inhibited by ammonium and ii) isoleucine may provide the carbon skeleton for synthesis of glutamate/glutamine in the detoxification of ammonium.  相似文献   
87.
The Ellman method for assaying thiols is widely used for cholinesterase activity measurement. Cholinesterase activity is measured indirectly by quantifying the concentration of 5-thio-2-nitrobenzoic acid (TNB) ion formed in the reaction between the thiol reagent 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) and thiocholine, a product of substrate (i.e., acetylthiocholine [ATCh]) hydrolysis by the cholinesterase. Oximes, reactivators of inhibited cholinesterase, are nucleophiles that also react with ATCh (oximolysis), producing thiocholine and (indirectly) TNB ion. The aim of this study was to characterize ATCh oximolysis. Therefore, we measured the oximolysis between oximes (K027 and HI-6) and ATCh in the presence of DTNB at different pH values, taking into account the final concentration of a product that is thiocholine. To confirm oximate ion involvement in the nucleophilic attack, we also determined the reaction rate between the oximes and ATCh, without DTNB, at different pH values by measuring the decrease in oximate ion absorption over time. The oximate ion of K027 reacted 14 times faster with ATCh (306M(-1)min(-1)) than the oximate ion of HI-6 (22M(-1)min(-1)). However, the rate constants obtained with the Ellman method were 84M(-1)min(-1) for K027 and 22M(-1)min(-1) for HI-6. Our results confirmed that the rate obtained with K027 using the Ellman method is actually the rate of the Ellman reaction itself. This suggests that the Ellman method cannot be used uncritically to evaluate oxime reaction with choline esters, in particular when oximolysis is faster than the Ellman reaction itself at a given pH.  相似文献   
88.
Human ATP-binding cassette (ABC) transporters comprise a family of 48 membrane-spanning transport proteins, many of which are associated with genetic diseases or multidrug resistance of cancers. In this study, we present a comprehensive approach for the cloning, expression, and purification of human ABC transporters in the yeast Pichia pastoris. We analyzed the expression of 25 proteins and demonstrate that 11 transporters, including ABCC3, ABCB6, ABCD1, ABCG1, ABCG4, ABCG5, ABCG8, ABCE1, ABCF1, ABCF2, and ABCF3, were expressed at high levels comparable to that of ABCB1 (P-glycoprotein). As an example of the purification strategy via tandem affinity chromatography, we purified ABCC3 (MRP3) whose role in the transport of anticancer drugs, bile acids, and glucuronides has been controversial. The yield of ABCC3 was 3.5 mg/100 g of cells in six independent purifications. Purified ABCC3, activated with PC lipids, exhibited significant ATPase activity with a Vmax of 82 +/- 32 nmol min-1 mg-1. The ATPase activity was stimulated by bile acids and glucuronide conjugates, reaching 170 +/- 28 nmol min-1 mg-1, but was not stimulated by a variety of anticancer drugs. The glucuronide conjugates ethinylestradiol-3-glucuronide and 17beta-estradiol-17-glucuronide stimulated the ATPase with relatively high affinities (apparent Km values of 2 and 3 microM, respectively) in contrast to bile acids (apparent Km values of >130 microM), suggesting that glucuronides are the preferred substrates for this transporter. Overall, the availability of a purification system for the production of large quantities of active transporters presents a major step not only toward understanding the role of ABCC3 but also toward future structure-function analysis of other human ABC transporters.  相似文献   
89.
Mitochondrial NADH:ubiquinone oxidoreductase is the largest and most complicated proton pump of the respiratory chain. Here we report the preparation and characterization of a subcomplex of complex I selectively lacking the flavoprotein part of the N-module. Removing the 51-kDa and the 24-kDa subunit resulted in loss of catalytic activity. The redox centers of the subcomplex could be reduced neither by NADH nor NADPH demonstrating that physiological electron input into complex I occurred exclusively via the N-module and that the NADPH binding site in the 39-kDa subunit and further potential nucleotide binding sites are isolated from the electron transfer pathway within the enzyme. Taking advantage of the selective removal of two of the eight iron-sulfur clusters of complex I and providing additional evidence by redox titration and site-directed mutagenesis, we could for the first time unambiguously assign cluster N1 of fungal complex I to mammalian cluster N1b.  相似文献   
90.
OPA1, a dynamin-related guanosine triphosphatase mutated in dominant optic atrophy, is required for the fusion of mitochondria. Proteolytic cleavage by the mitochondrial processing peptidase generates long isoforms from eight messenger RNA (mRNA) splice forms, whereas further cleavages at protease sites S1 and S2 generate short forms. Using OPA1-null cells, we developed a cellular system to study how individual OPA1 splice forms function in mitochondrial fusion. Only mRNA splice forms that generate a long isoform in addition to one or more short isoforms support substantial mitochondrial fusion activity. On their own, long and short OPA1 isoforms have little activity, but, when coexpressed, they functionally complement each other. Loss of mitochondrial membrane potential destabilizes the long isoforms and enhances the cleavage of OPA1 at S1 but not S2. Cleavage at S2 is regulated by the i-AAA protease Yme1L. Our results suggest that mammalian cells have multiple pathways to control mitochondrial fusion through regulation of the spectrum of OPA1 isoforms.  相似文献   
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