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Background: The single big cryoballon technique for pulmonary vein isolation (PVI) has been limited by the need for two transseptal punctures (TP). We therefore investigated feasibility and safety of a simplified approach using a single TP and a novel circumferential mapping catheter (CMC). Methods: Patients underwent 28‐mm cryoballoon PVI using a single TP. The CMC (Achieve© Medtronic Inc., Minneapolis, MN, USA) served as (1) guidewire and (2) as a PV mapping tool. Primary endpoint was PVI without switching to a regular guidewire. Secondary endpoints included: (1) PV signal quality during freezing, (2) time to PVI, (3) classification of successful ablation technique, (4) complications, and (5) procedural data. Results: A total of 32 patients (126 PVs) were studied (mean age: 62 ± 11 years, 24 males, left atrium: 40 ± 4 mm). The primary endpoint was achieved in 29/32 patients (91%) and 123/126 PVs (98%) with a procedure and fluoroscopy time of 126 ± 26 minutes and 18.9 ± 7.5 minutes, respectively. Real‐time visualization of PVI could be observed in 61/126 (48%) PVs. Time to sustained PVI versus nonsustained PVI was 66 ± 56 seconds versus 129 ± 76 seconds (P < 0.001). One phrenic nerve palsy was observed. After a follow‐up of 250 ± 84 days 23/32 patients (72%) remained in sinus rhythm. Conclusion: The “simplified single big cryoballoon” PVI strategy appears to be safe and feasible. However, real‐time PV recording was achieved in <50% of PVs. Therefore, further catheter refinements are warranted. (PACE 2012; 35:1304–1311)  相似文献   
94.
AIM:To molecularly characterize hepatitis B virus(HBV)isolates from Kerala and to relate them to the clinical manifestation of infection.METHODS:Sera and clinical data were collected from91 patients diagnosed with chronic HBV infection and HBV-related hepatocellular carcinoma(HCC).HBV from44 HCC,22 cirrhotic and 25 chronic hepatitis patients were genotyped by sequencing of the complete S region or by restriction fragment length polymorphism assays.The basic core promoter/precore region was sequenced.The complete surface DNA sequences were assembled and aligned manually,and then compared with the sequences of HBV of genotypes(A-J)from GenBank.The evolutionary history was inferred using the Neighbor-Joining method and the evolutionary distances computed using the Kimura 2-parameter method.Bootstrapping was performed using 1000 replicates.The TaqMan BS-1 probe was used to quantify HBV DNA at a lower detection limit of approximately20 IU/mL.Continuous variables were compared using an independent Student’s t test.Theχ2test or Fisher’s exact test was used to compare categorical variables.The differences were considered statistically significant at P<0.05.RESULTS:Irrespective of disease status,the predominant genotype was A(72%);95%belonging to subgenotype A1,followed by genotypes D(27%)and C(1%).HCC patients infected with subgenotype A1were significantly younger than those infected with D.Mutation A1762T/G1764A was significantly associated with HCC in both genotypes A and D.Mutation G1862T was more frequent in subgenotype A1(P<0.0001),and in combination with A1762T/G1764A,it was significantly associated with HBV from HCC patients.Mutation C1766T/T1768A was significantly associated with genotype A(P=0.05)and HCC(P=0.03).The preS2start codon M1T/I mutation was unique to genotype A strains(15.6%)from all disease groups and occurred at a higher frequency in isolates from HCC patients(P=0.076).A higher frequency of preS deletion mutants(33.3%)was observed in genotype A from HCC compared with non-HCC patients,but  相似文献   
95.
More than 69 million Indians are suffering from diabetes, of which a substantial proportion of the population are currently holding or will seek in the future the license to drive. Driving essentially requires multitasking with visuospatial skills at the same time and thus the management of diabetes in individuals which should demonstrate a proper detection and treatment of diabetes-related hypoglycemia will predict the capacity of driving any motor vehicle. Repeated hypoglycemia-related neuroglycopenia causes increased risk of neurocognitive dysfunction leading to visuospatial skills deficiency. Eight percent of dementia may be attributed to diabetes. Potential causes of driving impairment associated with diabetes are acute hypoglycemia, and its unawareness, retinopathy, neuropathy related to foot that affects ability to use pedals, IHD, cerebrovascular disease, somnolence and sleep disorder associated with obesity, use of pain relieving medications and antidepressant, and cognitive dysfunction and thus should be reviewed properly before issuing a driving license. Medical evaluation and documentation of acute and chronic complications of drivers by a registered medical practitioner at pre-determined intervals may be considered as a legal necessity to identify at-risk drivers. Secretagogues have a higher incidence of hypoglycemia compared to someone who is on metformin alone. On the other hand, hypoglycemia is more frequent in an insulin-treated patient of both type 1 and type 2 diabetes. In many countries as well as in European Union (EU), it is necessary to review medical fitness in every 3 years by the authority; a person should not have any severe hypoglycemic event in preceding 12 months and a driver must have awareness of hypoglycemia and its management. According to Canadian diabetes association consensus statement, review should be done every 2 years; a person should not have any severe hypoglycemic event in preceding 6 months, and according to ADA position statement evaluation should be done every 2–5 years. Medical fitness certificate should be reviewed at frequent intervals; the authorities should enforce strict regulation on suspension and revocation of driving license. Information to the authorities should be promptly done by doctors or patients. Decision should be based on medical evaluation, but hypoglycemia that occurs due to medication change and during sleep does not warrant for disqualification as it may be corrected with proper dietary changes and dose adjustments. Any driver with suspended license should be re-assessed in the next 6 months for their medical fitness and hypoglycemic profile and if found suitable, the license can be revoked. Physicians should participate and should assess patient’s physical and mental status, medical condition and treatment, list of medications which may impair driving performance, and any disease-related complication that lead to impaired driving or dangerous driving. Patient education is the most important factor to prevent any motor accident related to their medical condition and should be trained to prevent acute and chronic complications of diabetes.  相似文献   
96.
ObjectiveTo develop transfersomal formulation integrated with piperine intended for vitiligo.MethodsFilm hydration technique was employed in the preparation of transfersomes. Modified diffusion cell, consistency tester were fabricated for ex vivo diffusion studies and spreadability studies respectively while tape stripping method was integrated with tissue extraction in the determination of tissue drug concentration.ResultsWhen film hydration technique was used for, ultradeformable vesicles (transfersomes) of piperine in soabean phosphatidylcholine was formed with (67.11±0.22) to (70.55±3.62) and (60.12±1.04) to (80.43±0.14) mean size (μ) and entrapment efficiency (%) respectively. Transfersomes are capable of crossing the pores in permeability barriers extremely efficient even if the transfersome radius (tr) is much greater than the pore size (rpore) ie., tr/rpore? 0.25 the driven flux rate depends on the transdermal osmotic gradient. The vesicles describes elasto-mechanical character of vesicles while penetrating through the pores. The proviso is that the vesicular membrane elasticity is dynamically to the local stress by the external. Diffusion and Spreadability studies showed maximum diffusion when the lipid was kept minimum. Tape stripping and tissue extraction method for the tissue drug retention showed that (75.25±1.72)% drug was retained in the dermis.ConclusionSpan 80 was preferred over tween 80 in terms of dermal retention. Size and encapsulation was slightly altered by phosphatidylcholine concentration. The kinetics, efficiency and the transfersome mediated transport can be tailored for trans-epidermal, deep tissues and systemic depending on the vesicular composition, dose and form. Thus we have offered a successful drug delivery of piperine targeting the deep epidermis.  相似文献   
97.
ObjectiveTo evaluate the wound healing potency of aqueous extract of Aerva monsoniae (A. monsoniae) by in vitro method using fertilized eggs, in vivo analgesic and anti inflammatory activity in rodents and the anti bacterial activity on the bacterial strains that infect the wound.MethodsThe whole plant of A. monsoniae was extracted with water and then subjected to preliminary chemical screening. It was then evaluated for in ova angiogenesis on fertilized white leg horn eggs using the concentrations of 200-600 μ g/mL. The analgesic activity was evaluated in mice using the dose 100 and 250 mg/kg. The anti inflammatory activity was evaluated in rats using the dose 250 mg/kg and 500 mg/kg. In both the parameters water was used as the control and diclofenac was used the standard. The anti bacterial activity on Staphylococcus aureus and Pseudomonas aerugenosa was performed.ResultsThe phytochemical screening revealed the presence of tannins, flavonoids and saponins. The in ova angiogenesis revealed a dose dependent activity which proves the wound healing claim of the plant as more number of blood capillaries were formed at the site of the drug. The plant proved to be a potent analgesic and anti inflammatory agent at doses 100 mg/kg and 250 mg/kg. The anti bacterial activity was present but at higher doses.ConclusionsThe parameters studied in the present investigation proved that the plant is a potent wound healer. Further in vivo wound healing studies on animal model is desired. As the extract showed potent analgesic, anti inflammatory and anti bacterial properties, it can be considered that when formulated into suitable formulation, and it can reduce the pain, inflammation and infections related to wound very well.  相似文献   
98.
Immunocompetent cells in bone marrow allografts have been associated with a graft-versus-leukemia (GVL) effect. To further characterize effector mechanisms that may be involved in this GVL phenomenon, we have previously established an in vitro model to identify allogeneic T- cell clones that selectively mediate cytotoxicity against a patient's leukemic cells, but not against nonleukemic lymphocytes from the same patient. We have modified this in vitro model to test whether the Ph1 chromosome and the P210 fusion protein it controls have a detectable role in leukemia-specific recognition by allogeneic T-cell clones. In this report, T-cell lines reactive with allogeneic Ph1 chromosome- bearing (Ph1+) chronic myeloid leukemia (CML) cell lines were derived and selected to be minimally reactive with Ph1 negative (Ph1-) lymphoid lines from the same patient. However, after prolonged culture, these same T-cell lines also mediated significant destruction of the Ph1- target cells from the same patients. These T-cell lines specifically recognized cells from the allogeneic CML patient to which they were sensitized, and were not contaminated by an outgrowth of natural killer cells. Furthermore, subclones could be derived from these T-cell lines, and some of these subclones again showed selective killing of the allogeneic Ph1+ leukemia cell lines, and not of the Ph1- cell line from the same patient. Analyses of T-cell receptor (TCR) genes showed the alloreactive T-cell lines and the Ph1+ selective subclones derived from them to be of the same clonal origin. This suggests that the same T cells reacting with antigens expressed on the nonleukemic Ph1- targets can at times selectively and preferentially kill the allogeneic Ph1+ cells. As the same TCR that recognizes Ph1+ cells also can recognize the Ph1- targets, it appears that the Ph1+ chromosome does not play a detectable role in recognition by these allogeneic T-cell clones. This in vitro observation may provide a model for evaluating the relationship between GVL and graft-versus-host disease effects.  相似文献   
99.
ABSTRACT

Background

. Oral administration of bovine antibodies active against enterotoxigenic Escherichia coli (ETEC) have demonstrated safety and efficacy against diarrhea in human challenge trials. The efficacy of bovine serum immunoglobulins (BSIgG) against recombinant colonization factor CS6 or whole cell ETEC strain B7A was assessed against challenge with the CS6-expressing B7A.  相似文献   
100.
Attempts to maintain or expand primitive hematopoietic stem cells in vitro without the concomitant loss of their differentiative and proliferative potential in vivo have largely been unsuccessful. To investigate this problem, we compared the ability of three cloned bone marrow (BM) stromal cell lines to support the growth of primitive Thy- 1lo Sca-1+H-2Khi cells isolated by fluorescence-activated cell sorting from the BM of Ly-5.2 mice treated 1 day previously with 5-fluo- rouracil. Sorted cells were highly enriched in cobblestone area-forming cells (CAFC), but their frequency was dependent on the stromal cell lines used in this assay (1 per 45 cells on SyS-1; 1 per 97 cells on PA6). In the presence of recombinant leukemia inhibitory factor (LIF), CAFC cloning efficiency was increased to 1 per 8 cells on SyS-1 and 1 per 11 cells on PA6, thus showing the high clonogenicity of this primitive stem cell population. More primitive stem cells with competitive repopulating potential were measured by injecting the sorted cells into lethally irradiated Ly-5.1 mice together with 10(5) radioprotective Ly-5.1 BM cells whose long-term repopulating ability has been "compromised" by two previous cycles of marrow transplantation and regeneration. Donor-derived lymphocytes and granulocytes were detected in 66% of animals injected with 50 sorted cells. To quantitate the maintenance of competitive repopulating units (CRU) by stromal cells, sorted cells were transplanted at limiting dilution before and after being cultured for 2 weeks on adherent layers of SyS-1, PA6, or S17 cells. CRU represented 1 per 55 freshly sorted cells. CRU could be recovered from cocultures supported by all three stromal cell lines, but their numbers were approximately-sevenfold less than on day 0. In contrast, the addition of LIF to stromal cultures improved CRU survival by 2.5-fold on S17 and PA6 cells (approximately two-fold to threefold decline), and enabled their maintenance on SyS-1. LIF appeared to act indirectly, because alone it did not support the proliferation of Thy- 1lo Sca-1+H-2Khi cells in stroma-free cultures. Polymerase chain reaction (RT-PCR) analysis revealed that Interleukin-1beta (IL-1 beta) IL-2, IL-6, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, transforming growth factors, LIF, and Steel Factor (SLF) mRNAs were upregulated in SyS-1 within 1 to 6 hours of LIF-stimulation. To determine if increased expression of SLF by LIF-stimulated SyS-1 cells could account for their capacity to support stem cells, sorted calls were cocultured on simian CV-E cells that were transfected with an expression vector encoding membrane-bound SLF, or supplemented with soluble SLF. In both cases, SLF synergized with IL-6 produced endogenously by CV-E cells enabling CAFC growth equivalent to that on LIF-stimulated SyS-1. CAFC development on LIF- stimulated SyS-1 could also be completely abrogated by an anti-SLF antibody. These data provide evidence for a role of LIF in the support of long-term repopulating stem cells by indirectly promoting cytokine expression by BM stroma. Furthermore, we have used quantitative assays to show a maintenance of CRU numbers, with retention of in vivo function following ex vivo culture.  相似文献   
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