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21.
The extracellular matrix is essential for brain development, lamination, and synaptogenesis. In particular, the basement membrane below the pial meninx (pBM) is required for correct cortical development. The last step in the catabolism of the most abundant protein in pBM, collagen Type IV, requires prolidase, an exopeptidase cleaving the imidodipeptides containing pro or hyp at the C-terminal end. Mutations impairing prolidase activity lead in humans to the rare disease prolidase deficiency characterized by severe skin ulcers and mental impairment. Thus, the dark-like (dal) mouse, in which the prolidase is knocked-out, was used to investigate whether the deficiency of prolidase affects the neuronal maturation during development of a brain cortex area. Focusing on the cerebellar cortex, thinner collagen fibers and disorganized pBM were found. Aberrant cortical granule cell proliferation and migration occurred, associated to defects in brain lamination, and in particular in maturation of Purkinje neurons and formation of synaptic contacts. This study deeply elucidates a link between prolidase activity and neuronal maturation shedding new light on the molecular basis of functional aspects in the prolidase deficiency.  相似文献   
22.
Endometriosis is the most common cause of chronic pelvic pain in adolescent girls (50-70%), unresponsive to treatment of oral contraceptives and non-steroidal anti-inflammatory drugs. The most common symptoms of the disease are: acquired or progressive dysmenorrhea, acyclic and cyclic pain, dyspareunia (in sexually active girls), urological symptoms and gastrointestinal complaints. When evaluating an adolescent with suspected endometriosis, a gynecological examination (rectal or vaginal examination) and imaging studies (ultrasonography, magnetic resonance) should be performed. Moreover, in diagnostic process laparoscopy should be carried out in all girls and teenagers with chronic pelvic pain unresponsive to medical treatment. Initial therapy of endometriosis in adolescent girls involves: surgical methods (laparoscopy/laparotomy), hormonal pharmacotherapy (combined contraceptives, progestin-only protocols), GnRH agonists (adolescents over 16 years of age), non-steroidal anti-inflammatory drugs, alternative pain therapies and psychotherapy. Early diagnosis and treatment during adolescence may decrease disease progression and prevent subsequent infertility.  相似文献   
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The aim of the presented work was to evaluate whether short subcutaneous (s.c.) administration of TNFalpha-inducer-Tolpa Peat Preparation (TPP or TPP batch 0210) modulates the process of ischemic remodeling and spontaneous angiogenesis after experimental myocardial infarction (MI) in rats in vivo. The results obtained using three complementary and correlative methods: histological studies, Proliferating Cell Nuclear Antigen (PCNA) reaction and Lymphocytes Induced Angiogenesis (LIA) test showed a clear pro-angiogenic and cardioprotective effect of TPP administration after experimental MI. TPP batch 0210 should be considered as an angiogenesis stimulating factor and consecutively as a cardioprotective preventing development of ischemic cardiomyopathy after MI in rats. It might possibly be used as an adjunct to conventional therapy of coronary artery disease, including late phase after myocardial infarction or ischemic cardiomyopathy.  相似文献   
25.
Kósa E  Csákváry V 《Orvosi hetilap》2004,145(9):473-478
PURPOSE: Analysis of neurofibromatosis type I in children with special respect to ophthalmological symptoms. METHODS: It was performed a retrospective review of 18 children in period 1986-2002. The authors analysed the clinical, especially ophthalmological data, and the treatment of ophthalmological signs. RESULTS: The most frequent were the skin symptoms. All of the 18 patients had cafe au lait spots; 4 children had cutane neurofibroma; In 3 patients plexiform neurofibroma were observed. Ocular symptoms were: cutane neurofibroma in the left upper eye lid: 1 case; Lisch nodules in the iris: 5 cases; bilateral optic pathway glioma: 3 cases. One child's bilateral gliomas were inoperable, because of the intracranial progression. One child underwent surgical treatment because of the extreme exophthalmus in the right eye. Her left eye's glioma and the third case bilateral glioma needed only observation because of the loss of clinical signs, and slow progression. Family examinations were also performed: 12 children had signs in the II., III. and IV. generations, there were no symptoms in 6 family, they were new mutations. CONCLUSIONS: The most serious cases had ophthalmological symptoms, namely bilateral visual pathway gliomas that could lead to blindness. The treatment needed individually medical decision.  相似文献   
26.
The suppression of lymphopoiesis and immune competence during the maintenance phase in children with acute lymphoblastic leukemia (ALL) and the occurrence of infectious complications remain an unexplored area. In this study we assessed lymphocyte subpopulation disturbances during maintenance for childhood ALL along with the incidence, type, and severity of infections that occur during that period in the absence of neutropenia. Twenty-eight children (13 boys, 15 girls) with ALL aged 3-14 years (median 7 years) and treated according to the ALL-BFM 90/95 protocol were studied during maintenance for ALL. Complete white blood cell (WBC) counts and peripheral blood lymphocyte (PBL) analyses were performed. Major lymphocyte subsets (CD19+, CD3+CD4+, CD3-CD8+, CD3-CD16+CD56+, CD45RA-, CD45RO+) and markers of T-cell activation (CD25, CD38, CD69, HLA-DR) were analyzed with flow cytometry. Serum immunoglobulin G (IgG), IgA, and IgM levels were measured by a nephelometric assay. All infectious episodes during the study period were recorded in detail. Additionally, 41 age-matched immunocompetent children were used as controls. Absolute WBC counts (median, 3627/microL) and PBL counts (median, 1206/microL) were significantly below the age-adjusted control values (7400/microL and 2673/microL, respectively; P < .0001). B-lymphocyte, total CD4+, and memory CD4+ (CD4+CD45RO+) subsets were also significantly decreased (33/microL versus 377/microL [P < .0001], 531/microL versus 1045/microL [P < .01], and 80/microL versus 299/microL [P < .001], respectively). Significantly lower immunoglobulin levels were found in all patients. Twenty-two of the 28 patients presented with 74 episodes of a variety o minor infections (mostly respiratory viral [39], skin [7], and gastrointestinal [3]), none demanding prolonged hospital treat ment. Our findings demonstrate a profound immunosuppression throughout maintenance therapy in children with ALL tha has no major clinical impact in terms of increased incidence or severity of systemic infections.  相似文献   
27.
It has recently been proposed that endothelin-1 (ET-1) is an important activator of natriuretic peptide [atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP)] release in the heart and may mediate ANP and BNP deliberation to myocardial stretch and ischemia. The close inter-relationship between ET-1 and natriuretic peptide release was indicated mainly by the results of in vitro studies. In vivo, the local alterations of ANP and BNP levels in the myocardial interstitium can be well characterized by the changes of their pericardial fluid concentrations. The effect of the intrapericardially administered ET-1 on natriuretic peptide concentrations was studied on the in situ dog heart (n = 8). Control and three consecutive infusate samples were removed from the pericardial sac following ET-1 administration (150 pmol/kg) and parallel peripheral blood samples were taken to determine the ANP and BNP concentrations (enzyme-linked immunosorbent assay). Standard hemodynamic parameters were recorded continuously. In our results the intrapericardial ET-1 increased pericardial ANP but not BNP concentrations significantly (control versus ANPmax, 37 +/- 5 ng/mL versus 94 +/- 12 ng/mL; P < 0.02). ET-1 elicited significant ST elevations without changes of the hemodynamic values and the natriuretic peptide levels in the arterial plasma samples. In conclusion, intrapericardial ET-1 effectively stimulated the myocardial ANP release, which was reflected as elevation in the pericardial ANP level. The results also support the hypothesis that important regulatory mechanisms might be activated from the pericardium.  相似文献   
28.
Naturally occurring phenolics, protocatechuic and tannic acids have been reported to be inhibitors of chemical mutagenesis and carcinogenesis in experimental models. Here, we have studied the effect of pretreatment with these compounds on MC-induced cytochrome P450 and phase II enzymes in rats. The male Wistar rats were treated intraperitoneally with protocatechuic acid and tannic acid in the dose of 50mg/kg every 3 days for 2 weeks. MC was administered at the 12th day of phenolics treatment. The activities of EROD (CYP1A1), MROD (CYP1A2), PROD (CYP2B), PNPH (CYP2E1), GST, UDPGT, NQO1 were measured in the liver and kidney. Protocatechuic acid treatment minimally reduced the MC-induced EROD and MROD, but the observed differences were statistically significant. This compound was also a weak inhibitor of hepatic PNPH. Moreover, Western blot analysis with CYP1A1/1A2- and CYP2E1-specific antibodies showed the same effect in the levels of hepatic CYP1A1/1A2 and CYP2E1. Minimal decrease of renal constitutive (by 23%) and more significant reduction of induced form (by 66%) of PNPH was found as result of treatment with protocatechuic acid. Tannic acid alone had no effect on cytochrome P450 enzymes while in combination with MC this polyphenol minimally enhanced the MC induction of MROD and in greater extent PNPH in liver. The treatment with protocatechuic acid alone enhanced slightly the activities of all three phase II enzymes in liver. The pretreatment with this phenolic of the MC-induced rats however significantly increased the activities of hepatic GST and NQO1 in comparison with MC-treated group. In kidney MC-induced activity of NQO1 was reduced (about 43%) to the control level by tannic acid pretreatment. The results of our present study indicate that in rat the prolonged treatment with protocatechuic acid affects differently the activities of CYP and phase II enzyme when compared to tannic acid. Moreover, the effect of this polyphenols significantly depends on the method of treatment.  相似文献   
29.
We describe the case of a patient treated with 2-chloro-2'-deoxyadenosine, CdA or Cladribine for hairy cell leukemia who subsequently developed an Epstein Barr virus (EBV)-positive polymorphous large B-cell lymphoma (p-LBCL). The time interval between Cladribine therapy and development of p-BCL was 11 months and morphologically resembled an EBV-positive post transplant lymphoproliferative disorder (PTLD). Molecular genetic studies for EBV-clonality by Southern blot hybridization showed a clonal population of infected cells, implying that this was an EBV induced lesion. The chronology of events suggest that Cladribine, a purine analog which has been previously described to induce long-lasting immunodeficiency, can, in some cases, weaken the host defense mechanism to a level at which an innocuous EBV infection may transform the normal lymphoid cells into an aggressive neoplasm. Unlike most methotrexate-related lymphoproliferative disorders (LPDs), which undergo spontaneous remission after discontinuation of therapy, LPDs secondary to purine analogs often fails to resolve after discontinuation of therapy and requires additional therapy. Our patient was treated with rituximab following the diagnosis of p-LBCL, with the goal of improving the pancytopenia to permit chemotherapy. However, the patient failed to show any dramatic improvements in counts, developed systemic symptoms and progressive ascites. He expired 3 weeks after a second dose of rituximab. Cladribine is a potent immunosuppressive agent and should be included with the list of immunosuppressive agents that may be associated with EBV-related B-cell lymphoproliferative disorders.  相似文献   
30.
The ultrastructure of the interaction between the lysosomal compartment and the Mycobacterium tuberculosis-containing phagosomes in human resident alveolar macrophages has been analyzed in detail. Our findings confirm the widely accepted notion that the parasitophore vacuole is made nonfusogenic by the microorganism; however, the association between the lysosomal compartment and the phagosomes does not seem to be impaired as the organelles were shown to spread around the ingested pathogen. Furthermore, interruptions in the phagosome membrane that connect the bacterial surface with the cytosol were observed.  相似文献   
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