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91.
Kearns-Sayre syndrome (KSS) is a multisystem mitochondrial disorder characterized by the invariant triad: onset before 20, progressive external ophthalmoplegia and pigmentary retinal degeneration, plus at least one of the following: complete (or not) heart block, cereberal dysfunction and CSF protein above 100 mg/dl. Autopsies from patients with KSS revealed widespread tissue distribution mtDNA deletions. These deletions result in significantly lower activities of the enzymes of the respiratory chain. The same deletion of mitochondrial DNA present in skeletal muscle is found in myocardial tissue. An 18-year-old girl diagnosed with the KSS was admitted to our hospital because of an upper respiratory tract infection and dysphagia. ECG showed cardiac conduction defects. The patient had no history of syncope. At her surface ECG there was a complete RBBB (QRS duration approximately 130 ms), a clockwise rotation with an axis of approximately 90 degrees and a slight QT prolongation (420 ms). Echocardiography showed prolapse with thickening and degeneration of both mitral valve leaflets but without mitral regurgitation. The patient was started on a diet rich in potassium and pharmaceutical therapy with magnesium oxide (240 mg of elemental Mg p.o. per day), 1 g of calcium carbonate t.i.d., vitamin D (calcitriol 0.25 microg p.o. per day) and coenzyme Q(10) 100 mg daily and discharged 6 days later with slightly improved biochemical profile but apparent clinical improvement. Urgent pacemaker implantation was decided but unfortunately the patient died due to acute cardiac arrest 10 days later.  相似文献   
92.
We evaluated the medium-term results of combined Chiari pelvic and femoral osteotomies performed at the Manchester Children’s Hospitals between the years 1985 and 1994. The indications for these osteotomies were either hip dislocation or subluxation in children with neuromuscular disease. We clinically and radiologically evaluated 20 hips in 18 patients treated for hip subluxation and dislocation with Chiari osteotomy. The average post-operative clinical follow-up period was 11.32 years (range 10.1–12.9). The mean age at the time of surgery was 7.3 years (range 3.1–13.2 years). Clinically, 9 hips had a ‘Good’ outcome, 10 were “Fair” and 1 was “Poor” according to Osterkamp criteria. At last follow-up, radiologically the mean Sharp’s angle improved from 51° to 44° (p = 0.09), the mean Centre-Edge angle improved from −16° to 18° (p = 0.067), the mean Migration Index improved from 59 to 29 % (p = 0.011), the mean femoral neck-shaft angle from 160° to 117° (p < 0.0001) and the Severin criteria improved from an average grade of 4.5–2.9 (p < 0.0001). Our results compared to previous studies confirm that combined femoral and Chiari osteotomies provide a favourable outcome both clinically and radiologically at least 10 years following surgery. Accepting that the numbers are small, we report no statistical difference in the mean age at the time of operation when comparing the children with an eventual ‘good’ outcome and those with an eventual ‘fair’ or ‘poor’ outcome.  相似文献   
93.
During bone marrow engraftment following BMT there is a re-establishment of fetal erythropoiesis, expressed by the increase of F-cells. This seems to depend on several factors such as underlying disease, conditioning before therapy and other mechanisms concerning both the donor and the recipient bone marrow. The aim of this work was to study the factors influencing F-cell production during bone marrow engraftment following transplantation. We studied 28 patients who underwent allogeneic bone marrow transplantation, for various hematological malignancies (CML, AML, ALL, CMML and SAA). F-cells were estimated on peripheral blood smears by indirect immunofluorescence. Overall, there was an F-cell increase after BMT in comparison with values before BMT; this increase was significant on days 15–50 (p <.01). F-cell on days 18, 25, 32 and 40 following transplantation were significantly higher (p <.01) in patients who have had increased F-cell numbers post-chemotherapy before BMT, compared with the patients who did not show any increase of the F-cell number post chemotherapy. During the first month following transplantation (day 7 to day 40) patients who were transplanted from high F-cell donors failed to show any significant differences in their F-cell numbers in comparison to those transplanted from low F-cell donors. However, the F-cell increase became significantly higher in the former group between days 50 and 120. This observation implies that the stressed erythropoiesis of the initial phase does not allow revealing the varying F-cell production of the capacities donor bone marrow, while later, when the graft has settled, the high F-cell donors reveal this property of the host.  相似文献   
94.
95.

Introduction

HIV transmission risk is highest during acute HIV infection (AHI). We evaluated HIV RNA in the anogenital compartment in men who have sex with men (MSM) during AHI and compared time to undetectable HIV RNA after three-drug versus five-drug antiretroviral therapy (ART) to understand risk for onward HIV transmission.

Methods

MSM with AHI (n=54) had blood, seminal plasma and anal lavage collected for HIV RNA at baseline, days 3 and 7, and weeks 2, 4, 12 and 24. Data were compared between AHI stages: 1 (fourth-generation antigen-antibody combo immunoassay [IA]–, third-generation IA–, n=15), 2 (fourth-generation IA+, third-generation IA–, n=9) and 3 (fourth-generation IA+, third-generation IA+, western blot–/indeterminate, n=30) by randomization to five-drug (tenofovir+emtricitabine+efavirenz+raltegravir+maraviroc, n=18) versus three-drug (tenofovir+emtricitabine+efavirenz, n=18) regimens.

Results

Mean age was 29 years and mean duration since HIV exposure was 15.4 days. Mean baseline HIV RNA was 5.5 in blood, 3.9 in seminal plasma and 2.6 log10 copies/ml in anal lavage (p<0.001). Blood and seminal plasma HIV RNA were higher in AHI Stage 3 compared to Stage 1 (p<0.01). Median time from ART initiation to HIV RNA <50 copies/ml was 60 days in blood, 15 days in seminal plasma and three days in anal lavage. Compared with the three-drug ART, the five-drug ART had a shorter time to HIV RNA <1500 copies/ml in blood (15 vs. 29 days, p=0.005) and <50 copies/ml in seminal plasma (13 vs. 24 days, p=0.048).

Conclusions

Among MSM with AHI, HIV RNA was highest in blood, followed by seminal plasma and anal lavage. ART rapidly reduced HIV RNA in all compartments, with regimen intensified by raltegravir and maraviroc showing faster HIV RNA reductions in blood and seminal plasma.  相似文献   
96.
OBJECT: Anterior sacral meningocele (ASM) is a rare congenital malformation. Often while still asymptomatic, ASM may achieve a considerably size, to the extent of exerting a mass effect on the pelvic structures. Spontaneous rupture with subsequent septic meningitis is the most frequent and dangerous complication. The meningocelic sac is usually isolated by a surgical procedure that requires a sacral laminectomy or a transabdominal approach. Recently an alternative surgical technique, the posterior sagittal approach, has been proposed. METHODS: We report on a 15-year-old girl with a long clinical history of constipation and sporadic cystitis. Radiological examinations showed progressive enlargement of a presacral lipomeningocele, which grew to 12x14 cm. A posterior sagittal approach was performed; the stalk was ligated, the sac totally excised and a small associated tumour removed. No intra-/post-operative complications were observed. CONCLUSION: The posterior sagittal approach is an easy and safe surgical technique for the treatment of ASM, as it allows a complete isolation of the lesion and the removal of associated tumors without significant morbidity.  相似文献   
97.
Approximately 2154 regional blood centers and hospital-based blood banks and transfusion services responded to the 1991 American Association of Blood Banks Institutional Membership Questionnaire that elicited data from 1990. Information from 2144 institutions was considered valid. Questionnaire topics were donor blood collections, hemapheresis, perioperative cell salvage, component usage, and transfusion-associated diseases. Institutional members reported collecting 9.3 million units, of which 90.9 percent were for allogeneic use in the community, 6.0 percent were for autologous use, and 3.1 percent were directed donations. The percentage of directed-donor units that were crossed over for allogeneic use (51%) was greater than the percentage of units transfused to the designated patient (49%). Only 12.5 percent of institutions reported obtaining specific consent for transfusion. Of the 15.4 million transfused blood components, 8.5 million were red cells, 4.1 million were platelets, 1.8 million were fresh-frozen plasma, and 0.9 million were cryoprecipitate. There were 1263 reported cases of transfusion-associated hepatitis. Approximately 44 percent of the patients who were tested proved positive for hepatitis B surface antigen, and 80 percent of the patients who were tested proved positive for antibody to hepatitis C. The questionnaire's aggregate results can be used to assess current patterns of blood donation and transfusion activities.  相似文献   
98.
Jennings  LK; Phillips  DR; Walker  WS 《Blood》1985,65(5):1112-1119
Hybridomas secreting monoclonal antibodies (MoAbs) to human platelet membrane glycoprotein IIb (GPIIb) were prepared by fusing cells of a mouse myeloma line to spleen cells from a BALB/c mouse immunized with purified GPIIb. Six of the hybridomas secreted MoAbs that recognized epitopes on the 23,000-dalton, disulfide-linked subunit of GPIIb, GPIIb beta. All six of these MoAbs agglutinated platelets in the absence of calcium. The agglutination titers of three of the MoAbs, however, were enhanced between 2 and 6 log2 dilutions when titrated in the presence of mmol/L of calcium. The enhancement in titer was the result of MoAb- induced platelet activation followed by platelet aggregation, a reaction that could also be initiated by the monovalent Fab fragments prepared from one of the MoAbs. The MoAbs did not significantly agglutinate platelets from patients with Glanzmann's thrombasthenia, confirming biochemical evidence that there is a paucity of GPIIb beta in the membranes of these cells. Our results show that MoAbs to epitopes on GPIIb beta initiate distinct platelet responses; therefore, they should be useful for studying the ways in which regions of surface glycoproteins are involved in platelet-platelet interactions. In addition, these reagents may prove of value in diagnosing and typing patients with Glanzmann's thrombasthenia.  相似文献   
99.
The consultation is the core of medicine. Consultations makeup more than two-thirds of the workload of a family doctor,but the number of books on the topic is surprisingly small.Those who have read these authors' first book  相似文献   
100.
Gastric angiodysplasia   总被引:1,自引:0,他引:1  
Roberts  LK; Gold  RE; Routt  WE 《Radiology》1981,139(2):355
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