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71.

Background

Diabetic patients are more likely to develop kidney stones than the general population. The underlying mechanisms for this disparity remain to be elucidated. Little is known about the relationship between urine composition and diabetes mellitus in non-stone-forming individuals. We sought to examine the differences in the 24-hour (24-h) urine composition between diabetic and non-diabetic adults who were not stone formers.

Methods

A convenience sample of 538 individuals without a history of nephrolithiasis, gout, hyperparathyroidism, or gastroenteric diseases participated in this study. The 24-h urine profiles of 115 diabetic adults were compared with those of 423 non-diabetic adults. Diabetes was defined by self-reported physician diagnosis or medication use. All participants were non-stone formers confirmed by urinary tract ultrasonography. Participants provided a fasting blood sample and a single 24-h urine collection for stone risk analysis. Student’s t-test was used to compare mean urinary values. Linear regression models were adjusted for age, gender, body mass index, hypertension, fasting serum glucose, serum total cholesterol, estimated creatinine clearance rate and urinary factors.

Results

Univariable analysis showed that the diabetic participants had significantly higher 24-h urine volumes and lower urine calcium and magnesium excretions than non-diabetic participants (all P < 0.05). After multivariate adjustment, no significant differences in 24-h urine composition were observed between diabetic and non-diabetic participants except for a slightly increased 24-h urine volume in diabetic participants (all P > 0.05). The main limitation of this study is that the convenience samples and self-reported data may have been sources of bias.

Conclusion

Our data showed that there were no differences in 24-h urine composition between diabetic and non-diabetic adults who are not stone formers. The reason for it might be the improved glycemic control in diabetic individuals in our study. Therefore, a tighter glycemic control might reduce stone formation in diabetic adults.  相似文献   
72.
Abelmoschus manihot has drawn much attention recently due to its potential beneficial health effects after oral administration. However, the metabolic fate of A. manihot in intestinal flora is not well understood. In this paper, we describe a strategy using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS) with automated data analysis software (MetaboLynx?) for fast analysis of the metabolic profile of flavonoids from A. manihot in intestinal flora. The human and rat incubated samples collected 72 h in the anaerobic incubator were analyzed by UPLC-Q-TOF MS within 10 min. A total of 14 metabolites were identified in human and rat incubated solution compared with blank samples. The results indicated that hydrolysis, hydroxylation and acetylation were the major metabolic pathways of flavonoids in A. manihot extract in vitro. MS(E) was used for simultaneous acquisition of precursor ion information and fragment ion data at high and low collision energy in one analytical run, which facilitated the fast structural characterization of metabolites. This work demonstrated the potential of the UPLC-Q-TOF MS approach using Metabolynx for fast and automated identification of metabolites of natural product in intestinal flora.  相似文献   
73.
Alcoholic liver disease (ALD) is a serious fiver problem in western countries. Our previous study has demonstrated that vitamin C plays a protective role in ALD. The vitamin C homeostasis is tightly regulated by sodium-dependent vitamin C transporters (SVCTs) 1 and 2. But the role of two SVCTs in ALD is less understood. In this study, we exam- ined the expression patterns of two SVCTs in mice after alcohol consumption. Our results suggested that alcohol con- sumption obviously increased the expression of two SVCTs in liver and SVCT1 in kidney and intestine, which is important for vitamin C absorption. Vitamin C supplement increased the sera vitamin C content and ameliorated the symptom of ALD. Intestinal absorption and renal re-absorption mediated by SVCTI are key factors to increase the sera vitamin C content after alcohol consumption. We proposed that both reactive oxygen species and low vitamin C concentration regulate the expression of SVCTs, and the protective role of vitamin C is mediated by suppressing the stability of hypoxia-inducible factor-loL. Thus, our study is significant for the understanding of vitamin C homeostasis in ALD and for better use of other antioxidants in ALD therapy.  相似文献   
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75.
AimsThis retrospective study was carried out to compare the outcomes between elderly (≥70 years of age) and nonelderly patients (<70 years of age) with advanced hepatocellular carcinoma (HCC) who received sorafenib combined with transarterial chemoembolization (TACE).Methods88 patients with a confirmed diagnosis of advanced HCC were enrolled in this study. Of these, 24 elderly patients were matched with 48 nonelderly patients at a 1:2 ratio using propensity score matching to minimize selection bias. The related adverse events and survival benefits were compared between the two groups.ResultsSorafenib combined with TACE was equally well tolerated in both age groups, and grade 3 or 4 adverse events were similarly observed in 54.2% of elderly and 50.0% of nonelderly patients (P = 0.739). There were no significant differences in survival time between the elderly and nonelderly patients (P = 0.876). Significant prognostic factors for overall survival as identified by multivariate analysis were the Child–Pugh score and portal vein invasion.ConclusionsSorafenib combined with TACE may be well tolerated and effective in elderly patients with advanced HCC. Age alone is not a parameter for the treatment of advanced HCC patients.  相似文献   
76.
Ovarian cancer and malignant mesothelioma frequently express both mesothelin and CA125 (also known as MUC16) at high levels on the cell surface. The interaction between mesothelin and CA125 may facilitate the implantation and peritoneal spread of tumors by cell adhesion, whereas the detailed nature of this interaction is still unknown. Here, we used truncated mutagenesis and alanine replacement techniques to identify a binding site on mesothelin for CA125. We examined the molecular interaction by Western blot overlay assays and further quantitatively analyzed by enzyme-linked immunosorbent assay. We also evaluated the binding on cancer cells by flow cytometry. We identified the region (296–359) consisting of 64 amino acids at the N-terminal of cell surface mesothelin as the minimum fragment for complete binding activity to CA125. We found that substitution of tyrosine 318 with an alanine abolished CA125 binding. Replacement of tryptophan 321 and glutamic acid 324 with alanine could partially decrease binding to CA125, whereas mutation of histidine 354 had no effect. These results indicate that a conformation-sensitive structure of the region (296–359) is required and sufficient for the binding of mesothelin to CA125. In addition, we have shown that a single chain monoclonal antibody (SS1) recognizes this CA125-binding domain and blocks the mesothelin-CA125 interaction on cancer cells. The identified CA125-binding domain significantly inhibits cancer cell adhesion and merits evaluation as a new therapeutic agent for preventing or treating peritoneal malignant tumors.Ovarian cancer largely is confined to the peritoneal cavity for much of its natural history (1). Peritoneal mesothelioma is a highly invasive tumor originating from the mesothelial linings of the peritoneum (2). The development of effective drug regimens against ovarian cancer and mesothelioma has proven extremely difficult.Mesothelin was first identified in 1992 by the monoclonal antibody (mAb)2 K1 that was generated by the immunization of mice with human ovarian carcinoma (OVCAR-3) cells (3). The mesothelin gene encodes a 71-kDa precursor protein that is processed to a 40-kDa protein termed mesothelin, which is a glycosylphosphatidylinositol (GPI)-anchored glycoprotein present on the cell surface (4). Mesothelin is a differentiation antigen that is present on a restricted set of normal adult tissues such as the mesothelium. In contrast, it is overexpressed in a variety of cancers including mesothelioma, ovarian cancer, and pancreatic cancer (5). In addition, mesothelin is also expressed on the surface of non-small cell lung cancer cells (6, 7), especially most lung adenocarcinomas (8).We and others have shown that mesothelin is shed from tumor cells (9, 10), and antibodies specific for mesothelin are elevated in the sera of patients with mesothelioma and ovarian cancer (11). Shed serum mesothelin has been approved by the United States Food and Drug Administration (FDA) as a new diagnostic biomarker in mesothelioma. In a Phase I clinical study of an intrapleural interferon-β gene transfer using an adenoviral vector in patients with mesotheliomas, we found that antitumor immune responses targeting mesothelin were elicited in several patients (12). A recent study indicated that anti-mesothelin antibodies and circulating mesothelin relate to the clinical state in ovarian cancer patients (13). Pastan and colleagues (14) developed an immunotoxin (SS1P) with a Fv for mesothelin. Two Phase I clinical trials were completed at the National Cancer Institute (National Institutes of Health, Bethesda, MD) and there was sufficient antitumor activity of SS1P to justify a Phase II trial. A chimeric antibody containing the mouse SS1 Fv for mesothelin was also developed and is currently examined in a Phase I clinical trial for ovarian cancer, mesothelioma, pancreatic cancer, and non-small cell lung cancer (15).Mucins are heavily glycosylated proteins found in the mucus layer or at the cell surface of many epitheliums (16). There are two structurally distinct families of mucins, secreted and membrane-bound forms. CA125 (also known as MUC16) was first identified in 1981 by OC125, a mAb that had been developed from mice immunized with human ovarian cancer cells (17). The first cDNA clones were reported in 2001 (18, 19). CA125 is a very large membrane-bound cell surface mucin, with an average molecular mass between 2.5 and 5 million daltons. It is also heavily glycosylated with both O-linked and N-linked oligosaccharides (20). The peptide backbone of CA125 is composed of the N-terminal region, extensive Ser/Thr/Pro-rich tandem repeats (TR) with 156 amino acids each with both N- and O-glycosylations, a SEA domain with high levels of O-glycosylation and a C-terminal region with a short cytoplasmic tail (19). The SEA domain was first identified as a module commonly found in sea urchin sperm protein, enterokinase and agrin (21, 22). The significance of the SEA domain in CA125 is not clear.CA125 was originally used as a biomarker in ovarian cancer due to its high expression in ovarian carcinomas and that it is shed into the serum (23). A majority (88%) of mesotheliomas are also CA125 positive on the cell membrane (24). It was shown that 25% of peritoneal mesotheliomas have high CA125 expression (25). The intensity of CA125 membranous expression is indistinguishable between ovarian carcinomas and peritoneal mesotheliomas. Gene expression analysis using the SAGE tag data base has shown that mesothelioma has the second highest co-expression of CA125 and mesothelin after ovarian cancer (26). Rump and colleagues (26) have shown that mesothelin binds to CA125 and that this interaction may mediate cell adhesion. Scholler et al. (27) recently showed that CA125/mesothelin-dependent cell attachment could be blocked with anti-CA125 antibodies. Because mesothelin is present on peritoneal mesothelium, there may be an important role for the mesothelin-CA125 interaction in the tumorigenesis of ovarian cancer and mesothelioma in the peritoneal cavity. The mesothelin binding site on CA125 may lie within the 156-amino acid TR units, indicating multimeric binding of mesothelin to CA125. It has been found that the extraordinarily abundant N-glycans on CA125, presumably in the TR region, are required for binding to both glycosylated and non-glycosylated mesothelin (28).Here, we identified the binding site of CA125 on mesothelin by use of truncated mutagenesis and alanine replacement approaches. We measured binding qualitatively by Western blot overlay assays and quantitatively by enzyme-linked immunosorbent assay (ELISA). We also evaluated the interaction of CA125 and mesothelin on cancer cells by flow cytometry. Furthermore, we have shown that a single chain mAb (SS1) recognized the CA125-binding domain and blocked the mesothelin-CA125 interaction on cancer cells. The identified CA125-binding domain-Fc fusion protein also significantly inhibited cancer cell adhesion. Our results suggest that conformation-sensitive structures of the region (296–359) are required and sufficient for specific binding of mesothelin to CA125. The domain proteins or the antibodies that block the mesothelin-CA125 interaction merit evaluation as new therapeutic agents in treating peritoneal malignant tumors.  相似文献   
77.
Fungi were isolated from Meloidogyne spp. eggs and females on 102 field-collected root samples in China. Of the 235 fungi isolated (representing 18 genera and 26 species), the predominant fungi were Fusarium spp. (42.1% of the isolates collected), Fusarium oxysporum (13.2%), Paecilomyces lilacinus (12.8%), and Pochonia chlamydosporia (8.5%). The isolates were screened for their ability to parasitise Meloidogyne incognita eggs in 24-well tissue culture plates in two different tests. The percentage of eggs parasitised by the fungi, the numbers of unhatched eggs and alive and dead juveniles were counted at 4 and 7 days after inoculation. The most promising fungi included five Paecilomyces isolates, 10 Fusarium isolates, 10 Pochonia isolates and one Acremonium isolate in test 1 or test 2. Paecilomyces lilacinus YES-2 and P. chlamydosporia HDZ-9 selected from the in vitro tests were formulated in alginate pellets and evaluated for M. incognita control on tomato in a greenhouse by adding them into a soil with sand mixture at rates of 0.2, 0.4, 0.8 and 1.6% (w/w). P. lilacinus pellets at the highest rate (1.6%) reduced root galling by 66.7%. P. chlamydosporia pellets at the highest rate reduced the final nematode density by 90%. The results indicate that P. lilacinus and P. chlamydosporia as pellet formulation can effectively control root-knot nematodes.  相似文献   
78.
79.
A study was made to observe the effect of cobalt-60 irradiation on the viability of Paragonimus westermani metacercariae in Sinopotamon chekiangense crabs. The crabs were collected in mountain regions of the Zhejiang Province of China in which paragonimiasis is endemic. Adult cats and albino mice were infected with metacercariae irradiated at different doses. Dissection of the host animals was conducted 90 or 30 days, respectively, after infection for recovery of lung flukes. Anti-metacercariae antibody in infected mice was measured by enzyme-linked immunosorbent assay (ELISA). Results showed that metacercariae were unable to grow into adult worms in cats after exposure to gamma irradiation at a dose of 0.10 kGray. However, a small number of metacercariae exposed to a dose of 2.0 kGray excysted and survived in 1 mouse for 30 days. No worm was recovered from mice when the metacercariae were irradiated at a dose of 2.5 kGray. Seropositive results by ELISA were obtained when the mice were infected with metacercariae irradiated at doses ranging from 2.0 to 3.5 kGray.  相似文献   
80.
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