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91.
Background: Polymerase chain reaction (PCR) is useful for rapid microbial detection in body fluids with low microbial load. It is easier to use universal or broad range primers for the amplification of conserved stretches of DNA common to all bacteria like 16S rRNA gene, followed by restriction fragment length polymorphism (RFLP) of PCR products.  相似文献   
92.
Osteoporosis is prevalent in end‐stage liver disease, but data on long‐term changes in bone mineral density (BMD) and related fracture incidence after orthotopic liver transplantation (OLT) are scarce. We evaluated BMD changes up to 5 years in consecutive recipients of a successful OLT at the Leiden University Medical Centre between 2000 and 2011, in whom sequential BMD data were available. Spinal radiographs were available at time of screening and at 6 and 12 months post‐OLT and were assessed for vertebral fractures by two independent observers using Genant's semiquantitative method. Patients were excluded from the study when started on bisphosphonates. A total of 201 patients (71% men), median age 53 years (range, 18–70 years) were included in the study. Most common liver pathology was viral (27%) or alcoholic liver disease (25%). All patients received prednisone for at least 6 months after transplantation and the majority received either tacrolimus or cyclosporine for immunosuppression. At time of screening for OLT, osteoporosis and osteopenia were found in 18% and 36% of patients at the lumbar spine (LS), respectively, and in 9% and 42% at the femoral neck (FN), respectively. T‐scores declined significantly at both sites 6 months after OLT, but increased thereafter at the LS, reaching pretransplantation values at 2 years and remaining stable thereafter. FN T‐scores remained consistently lower than pretransplantation values. The prevalence of vertebral fractures increased from 56% at screening to 71% at 1 year after OLT, with a fracture incidence of 34%. BMD changes did not predict fracture risk. Osteoporosis, osteopenia, and vertebral fractures are prevalent in patients with end‐stage liver disease. An overall decline in BMD is observed within the first 6 months after OLT, with subsequent recovery to pretransplantation values at the LS, but not at the FN. Vertebral fracture risk is high after OLT regardless of changes in BMD. © 2014 American Society for Bone and Mineral Research.  相似文献   
93.

Objective

To generate life table characteristics for the dengue vector Aedes albopictus (A. albopictus) under uncontrolled conditions, incorporating both the aquatic and the adult stages.

Methods

Ten females derived from wild pupae were allowed to fully blood-feed on restrained mice. 774 eggs were hatched in seasoned water. F1 larvae were followed for development until their F2 counterparts emerged as adults. Some population parameters were monitored (F1) or estimated (F2).

Results

A. albopictus exhibited increased fecundity and egg hatch success. Immature development was quick. Immature survival was high, with lowest rate in the pupal stage. Adult emergence was about 81% and sex ratio was close to 1:1. Generational mortality (K) was about 28%. A high proportion of females completed a reproductive cycle and the obtained parity rate was predicted to lead to higher fecundity in the next generation.

Conclusions

It can be concluded that natural A. albopictus populations in Penang seem largely determined by quick development in combination with low immature loss and increased oviposition.  相似文献   
94.
Objective To study the abortifacient activity of aqueous extract of Senna alata leaves in female Wistar rats.Methods Pregnant rats weighing 143.65 ± 13.11 g were completely randomized into 5 groups(A-E).Rats in group A(negative control) were orally administered,once daily with 0.5 ml of distilled water on days 10-18 post-coitum while those in groups B,C,D,and E were treated exactly like the negative control except they received the same volume containing 2.85 mg/kg body weight of mifepristone(group B,reference drug),250,500 and 1 000 mg/kg body weight of the extract respectively(groups C-E).Results Phytochemical screening of the extract showed positive results for saponins(1.22%),flavonoids(1.06%),cardiac glycosides(0.20%),cardenolides and dienolides(0.18%),phenolics(0.44%) and alkaloids(0.52%).Respiratory distress,salivation,diarrhoea,changes in the appearance of hair as well as maternal mortality were not observed at any time during the exposure period except in the mifepristone-treated animals where there was episode of diarrhoea and tiredness.The extract significantly reduced(P〈0.05) the number of life foetus,weight and survival ratio of the foetus,numbers of implantations and Corpora lutea,implantation index,progesterone,prolactin,estradiol,follicle stimulating and luteinizing hormones whereas the number of dead foetus,number and percentage of rats that aborted,percentage vaginal opening,resorption index,pre-and post-implantation losses increased significantly.In addition,mifepristone-treated animals produced resorption index that compared well with the distilled water control.There was also no dead or life foetus and serum progesterone concentration was increased in the animals treated with mifepristone.All cases of abortion were accompanied with vaginal bleeding.Although,the final weight of the rats increased significantly,the feed and water intake were not significantly altered in all the treatment groups.The weight of the uterus,uterine-body weight ratio,length of the right uterus horn and uterine cholesterol decreased significantly in all the treatment groups.The uterine alkaline phosphatase activity and glucose concentration increased in only the extract-treated animals whereas mifepristone decreased the uterine alkaline phosphatase activity and glucose content of the animals.Conclusion This study has provided evidence to the age-long claim of S.alata leaves in "washing the uterus".The abortifacient properties were most pronounced at 500 and 1 000 mg/kg body weight of the extract and were similar to the animals treated with 2.85 mg/kg body weight of mifepristone.Hormonal influence,changes in implantation site,estrogenicity and uterogenicity are suggested as possible mechanism of abortifacient activity of aqueous extract of S.alata leaves.Overall,the extract may be used as an abortifacient especially at 500 and 1 000 mg/kg body weight and therefore not safe for consumption as oral remedy during pregnancy.  相似文献   
95.
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97.
Cellular DNA content distributions of propidium-iodide-stained bone marrow blasts were determined by flow cytometry (FCM) for 225 untreated children with acute leukemia and were correlated with leukemia cell phenotype and karyotype. Aneuploidy of the primary malignant stem line was detected in 54 cases (24%): 51 hyperdiploid and 3 hypodiploid. A second stem line with approximately twice the DNA content of the primary stem line was recognized by FCM in 28 cases (23 ALL, 5 ANLL) and may be an important source of leukemia cell heterogeneity. The degree of DNA content abnormality detected by FCM was highly correlated (r = 0.98) with the number of whole chromosome gains or losses in the leukemia karyotype. Aneuploidy detectable by FCM was more frequent in acute lymphoblastic leukemia (ALL) (52 of 173, 30.1%) than in acute nonlymphoblastic leukemia (2 of 52, 3.8%) (p less than 0.001). In the ALL group, aneuploidy was significantly correlated with the cell surface expression of common ALL antigen: 46 of 127 antigen-positive cases were aneuploid compared to 6 of 46 antigen-negative cases (p less than 0.003). Only 2 of 21 cases of T-cell ALL without common ALL antigen had detectable aneuploidy, which was significantly less than in the common ALL group (p = 0.02). The median percentage of cells in S- phase was significantly greater for B-cell and erythrocyte rosette- positive T-cell ALL, than for the other phenotypic subgroups. We conclude that aneuploidy and S-phase cell percentage are correlated with the state of leukemia cell differentiation. The biologic basis for the correlation is not established, but may be linked to the process of malignant transformation.  相似文献   
98.
Chronic knee pain assessed by SPECT: comparison with other modalities   总被引:3,自引:0,他引:3  
Twenty-seven patients with chronic knee pain were examined prospectively using conventional radiography, radionuclide angiography, planar bone scintigraphy, and single-photon emission computed tomographic (SPECT) bone scintigraphy. When the results of subsequent arthroscopic examination of all three compartments of the knee were correlated with those of the noninvasive methods, SPECT bone scintigraphy was found to be most sensitive for evaluating the extent of osteoarthritis. Differences in detection sensitivity for articular cartilage damage and synovitis were greatest in the patellofemoral compartment. The frequency with which hyperemia was present in association with cartilage damage and synovitis indicates that osteoarthritis of the knee is capable of producing hyperemia and further implies that increased perfusion cannot be used to distinguish with confidence between osteoarthritis and septic processes involving the knee. SPECT (1.00) and planar (0.91) bone scintigraphy were highly sensitive indicators of torn menisci in a subgroup of 14 patients, each having a prearthroscopic clinical diagnosis of a torn meniscus. This result suggests that for patients with chronic knee pain and clinical suggestion of a torn meniscus, bone scintigraphy has significant potential as a high-sensitivity, prearthroscopic screening examination.  相似文献   
99.
100.
ObjectiveTo estimate the timing of key events in the natural history of Zika virus infection.MethodsIn February 2016, we searched PubMed, Scopus and the Web of Science for publications containing the term Zika. By pooling data, we estimated the incubation period, the time to seroconversion and the duration of viral shedding. We estimated the risk of Zika virus contaminated blood donations.FindingsWe identified 20 articles on 25 patients with Zika virus infection. The median incubation period for the infection was estimated to be 5.9 days (95% credible interval, CrI: 4.4–7.6), with 95% of people who developed symptoms doing so within 11.2 days (95% CrI: 7.6–18.0) after infection. On average, seroconversion occurred 9.1 days (95% CrI: 7.0–11.6) after infection. The virus was detectable in blood for 9.9 days (95% CrI: 6.9–21.4) on average. Without screening, the estimated risk that a blood donation would come from an infected individual increased by approximately 1 in 10 000 for every 1 per 100 000 person–days increase in the incidence of Zika virus infection. Symptom-based screening may reduce this rate by 7% (relative risk, RR: 0.93; 95% CrI: 0.89–0.99) and antibody screening, by 29% (RR: 0.71; 95% CrI: 0.28–0.88).ConclusionNeither symptom- nor antibody-based screening for Zika virus infection substantially reduced the risk that blood donations would be contaminated by the virus. Polymerase chain reaction testing should be considered for identifying blood safe for use in pregnant women in high-incidence areas.  相似文献   
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