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1.
To relate technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-MIBI) uptake to regional myocardial blood flow (rMBF), 99mTc-MIBI single photon emission tomography (SPET) and H2(15)O positron emission tomography (PET) scans were obtained at rest and after dipyridamole infusion in six patients with single vessel coronary artery disease. 99mTc-MIBI and H2(15)O data sets were created for each segment perfused by the stenotic vessel and for a normal reference area, assigning regions on the SPET tomograms to comparable regions on the PET by similar transaxial image reconstructions. All patients demonstrated post-dipyridamole 99mTc-MIBI perfusion defects in the territories supplied by the stenotic arteries. Resting rMBF in these regions was slightly lower than that in the normal areas (0.82 +/- 0.05 vs 0.90 +/- 0.09 ml/g/min, P = NS). A 43% +/- 14% reduction in 99mTc-MIBI activity in the area at risk was coupled with on average a 60% +/- 9% reduction in post-dipyridamole rMBF compared with control regions (0.98 +/- 0.08 vs 2.52 +/- 0.51 ml/g/min, P < 0.001). Thus, SPET assessment of 99mTc-MIBI uptake tends to underestimate the perfusion contrast between areas with normal and areas with low coronary vasodilatory reserve when compared to PET. However, these findings may still not affect the clinical usefulness of 99mTc-MIBI and more extensive studies are required to confirm these results in the clinical environment.  相似文献   
2.
Intestinal malabsorption by jejunoileal bypass has been used to treat morbid obesity. Although the procedure is considered safe, several long‐term neurological complications have been described. A 47‐year‐old man was evaluated because of increasing gait difficulties five years after jejunoileal bypass at age 42. Neurological examination showed upper, lower extremities proximal weakness, distal sensory loss for touch, pin‐prick, vibration and position. Deep jerks were absent. Electrophysiology was consistent with axonal neuropathy. Blood tests revealed microcitic anemia (Hb 9 g/dl), normal thyroid function, tumor marker titer, and viral screenings. Vitamin A was 1.12 umol/l (n.v. 0.56–4.25) and vitamin E was 10.7 umol/l (n.v. 11.5–31). B12, folate levels were within normal range. A 42‐year‐old obese man had a similar surgery. Two years later he developed an acute episode of confusion and unsteadiness due to lactic acidosis, from which he recovered. He was first evaluated neurologically fifteen years after jejunoileostomy because of muscle cramps, paraesthesias, and progressive imbalance. On examination there were trunk, extremity ataxia, proximal and distal muscle weakness, distal atrophy, loss of reflexes, and severe loss of all sensory modalities. Electrophysiology confirmed a sensorimotor neuropathy. Blood tests showed macrocitic anemia, low free calcium (3.7 mEq/l, n.v. 4–5), increased PTH (75 pg/ml, n.v. 10–65), and low serum level of vitamins A and E. Brachial biceps biopsy showed neurogenic changes. General conditions progressively deteriorated because of repeated episodes of dehydration leading to terminal uremia within 27 years.  相似文献   
3.
Intracerebral (i.c.) Junin virus (JV) infection of adult BALB/c mice is characterized by the absence of morbidity and a low mortality (barely 8-10%). In contrast, the suckling mouse model exhibits almost 100% mortality following central nervous system (CNS) alterations consistent with a delayed-type hypersensitivity (DTH)-like immune response. Besides, JV infection of adult (resistant) mice leads to immunosuppression of DTH to unrelated antigens. Here we present evidence demonstrating that such suppression is mediated by JV-induced cells present in spleen from 24 hr to 24 days post-infection, bearing the Thy-1+, Ly-1+2- phenotype and reactive to an unrelated antigen such as sheep red blood cells (SRBC). No evidence of suppressor factors was found. A relatively low number of total splenic cells (5 x 10(6) cells/mouse) was enough to transfer suppression. Therefore, this cell population may be involved in adult mouse survival to JV infection.  相似文献   
4.
Wilson's disease is characterized by accumulation of copper and D-penicillamine favors its elimination. However, penicillamine binds to precursors of intermolecular crosslinks both in collagen and elastin, and could lead to alterations of these two fibrous proteins. In the present report skin biopsies from patients with Wilson's disease, treated with 900 mg/day of D-penicillamine, for 5, 9, 58 and 60 months, were studied by electron microscopy and compared with findings obtained from skin biopsies of age-matched normal subjects. Clinically, the elasticity and consistency of the skin of Wilson's patients was not modified by D-penicillamine treatment. The ultrastructural organization of collagen fibrils appeared normal in the adults treated with D-penicillamine for 5-9 months. In a 15-year-old girl, treated for 48 months, a high number of collagen fibrils were swollen and unreeved. Elastin fibers were altered in all patients. The alterations were mostly pronounced in the reticular dermis, were proportional to the time of treatment, and consisted of polymorphous aggregates of elastin connected to apparently normal elastin fibers. A stereological analysis, on EM pictures from the patient treated for 60 months, and from an age-matched control, showed a significant decrease in the percentage of collagen and of the mean area occupied by each collagen bundle in the reticular dermis of the patient compared to control; on the contrary, the number of elastin fibers per unit area increased significantly, and the mean area of each elastin fiber decreased. The volume density of elastin was similar to control. The results indicate that prolonged administration of penicillamine to humans induces alterations in the deposition of dermal collagen and elastin.  相似文献   
5.
In contrast to lymphocytic choriomeningitis virus, another arenavirus, Junin virus (JV), the etiologic agent of Argentine hemorrhagic fever, when inoculated into suckling mice, induces lethal meningoencephalitis characterized by a delayed-type hypersensitivity (DTH)-like immune response. However, the adult BALB/c mouse is resistant to infection and no DTH reaction can be seen. This different viral sensitivity may be related to the development of an antigen non-specific DTH-suppressor cell pathway at work in the adult mouse. When the resistant mice are treated with cyclophosphamide (Cy) (50 mg/kg each dose) given at days -1,+1,+4 (zero: infection day), animals become susceptible and develop DTH reaction in brain that leads to death. We analyze the influence of the timing of Cy administration on the suppressor system developing after infection. It was found that Cy depletes the previously described JV-induced suppressor populations (Tsv) but a new suppressor cell (Tsv*) is disclosed bearing the Thy 1+ Ly1+2- phenotype which is unable to depress DTH in Cy-treated animals. With only two doses of Cy corresponding to days -1 and +1, the target of Tsv* cells is depleted but the third dose is still required to achieve full depletion of Tsv cells which are able to employ the Cy-resistant antigen-specific suppressor cells as targets. Since the Cy treatment is able to deplete the Tsv population together with the target of Tsv* cells, animals became unable to regulate lethal DTH reaction. Thus, a cellular explanation for an empirically established Cy schedule able to abrogate the adult mouse resistance to JV is proposed.  相似文献   
6.
Two females mother and daughter, were affected by a neuromuscular disorder, characterized by slow progression, humeroperoneal weakness and wasting, limited neck flexion, elbow and ankle joint contractures, cardiopathy and myopathic pattern on EMG. Muscle histology and histochemistry showed type I fiber atrophy and predominance in both. Cardiac abnormalities, in the first case, were suggestive of a hypertrophic cardiomyopathy while in the second hypotension and chronic bradycardia were present.Neurological signs, EMG and morphology seemed to point to a genetic variant of the form of dystrophy named Emergy-Dreifuss disease.The mode of transmission and cardiac abnormalities, however, raise the problem of variability even in this well-defined, usually X-linked, disorder.
Sommario Questa è la prima descrizione di madre e figlia affette da una infrequente malattia muscolare, caratterizzata da progressione lenta, ipostenia con atrofia a distribuzione omero-peroneale, presenza di contratture articolari, cardiopatia e pattern miopatico dell'EMG.Istologia e istochimica muscolare hanno mostrato in entrambi i soggetti atrofia e predominanza delle fibre del I tipo. Le anormalità cardiologiche rilevate nel 1° caso, erano a favore di una cardiomiopatia ipertrofica, mentre nel secondo caso erano presenti ipotensione e bradicardia.Segni neurologici, elettromiografici, reperti istologici ed istochimici sembrano configurare nelle nostre pazienti una variante genetica della forma di distrofia muscolare chiamata Emery-Dreifuss disease. Tuttavia, la modalità di trasmissione e il tipo delle anormalità cardiologiche, diverse nelle due pazienti, sollevano il problema di variabilità fenotipiche, anche in entità clinico-genetiche usualmente ben definite quali la malattia di Emery-Dreifuss.
  相似文献   
7.
The authors report the results of 18 hemiarthroplasties of the shoulder performed between 1990 and 1994 using the Neer II monoblock prosthesis, emphasizing the technical and surgical problems encountered. The patients treated numbered 13 for traumatic pathology (acute fractures: 7; sequelae of fracture of the proximal epiphysis of the humerus: 6), and 5 for degenerative lesions (arthrosis: 3; rheumatoid arthritis: 2). An evaluation of the results was based on the Constant method and isokinetic testing. Results based on follow-up obtained after 2 to 6 years were satisfactory in 83% of the cases.  相似文献   
8.
PURPOSE: To determine whether tamoxifen or anastrozole prevents gynecomastia and breast pain caused by bicalutamide (150 mg) without compromising efficacy, safety, or sexual functioning. PATIENTS AND METHODS: A double-blind, placebo-controlled trial was performed in patients with localized, locally advanced, or biochemically recurrent prostate cancer. Patients (N = 114) were randomly assigned to either bicalutamide (150 mg/d) plus placebo or in combination with tamoxifen (20 mg/d) or anastrozole (1 mg/d) for 48 weeks. Gynecomastia, breast pain, prostate-specific antigen (PSA), sexual functioning, and serum levels of hormones were assessed. RESULTS: Gynecomastia developed in 73% of patients in the bicalutamide group, 10% of patients in the bicalutamide-tamoxifen group, and 51% of patients in the bicalutamide-anastrozole group (P < .001); breast pain developed in 39%, 6%, and 27% of patients, respectively (P = .006). Baseline PSA level decreased by > or = 50% in 97%, 97%, and 83% of patients in the bicalutamide, bicalutamide-tamoxifen, and bicalutamide-anastrozole groups, respectively (P = .07); and adverse events were reported in 37%, 35%, and 69% of patients, respectively (P = .004). There were no major differences among treatments in sexual functioning parameters from baseline to month 6. Elevated testosterone levels occurred in each group; however, free testosterone levels remained unchanged in the bicalutamide-tamoxifen group because of increased sex hormone-binding globulin levels. CONCLUSION: Anastrozole did not significantly reduce the incidence of bicalutamide-induced gynecomastia and breast pain. In contrast, tamoxifen was effective, without increasing adverse events, at least in the short-term follow-up. These data support the need for a larger study to determine any effect on mortality.  相似文献   
9.
We report possibly the oldest evidence of gynecomastia in mummified human remains. Computed tomography was performed on the mummified remains of an early 17th century Northern Finnish vicar. The examination of the scans revealed large bilateral subareolar irregular masses resembling female mammary glands. The nearly septuagenarian vicar appears to have had gynecomastia, as it is a common condition in elderly men, and is sometimes associated with obesity. Gynecomastia is the most likely explanation for these findings. Clin. Anat. 31:641–644, 2018. © 2018 Wiley Periodicals, Inc.  相似文献   
10.
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