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41.
Scedosporium inflatum, an emerging pathogen.   总被引:3,自引:4,他引:3       下载免费PDF全文
The salient morphologic and physiologic characteristics of 18 isolates of Scedosporium inflatum, a newly reported human pathogen, were compared with those of the morphologically similar fungi Scedosporium apiospermum, Scopulariopsis brevicaulis, and Scopulariopsis brumptii. The formation by S. inflatum of annelloconidia in wet clumps at the apices of annellides with swollen bases was found to be the most useful characteristic in differentiating this potential pathogen.  相似文献   
42.
To date the concurrent presence of the fragile-X and the Klinefelter syndromes in the same individual has been found at least 8 times either in the course of screening for the fra(X) condition in mentally retarded males or among the relatives of fra(X) propositi. Given the high frequency of both events in the general population and the heterogeneous approaches with which the above cases were ascertained, it has not been possible to determine unequivocally so far whether the finding is purely coincidental or the expression of some underlying biological relationship. To evaluate the issue, we have screened a large population of institutionalized mentally retarded males for microorchidism, and submitted to a full karyotype analysis and fra(X) testing the patients that were found to have marked bilateral microorchidism. Thus, in a total of 32 microorchidism patients identified among 1115 mentally retarded males, we found 6 to have a 47,XXY chromosome complement in all (or in most) of their cells, with one of them having also the fra(X) marker in 9% of the metaphases examined. In addition, another bearer of the fra(X) marker (but only in 4% of his metaphases) was found among 26 47,XXY mentally normal males ascertained throughout routine cytogenetic analysis of males with microorchidism referred to our genetic counseling unit during the last 10 years. In our laboratory the fra(X) marker has never been observed with such a frequency in a total of several hundred normal XY males and XX females studied as control cases in the course of previously reported family and population studies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
43.
We have reported 7 new cases of Bipolaris infection and 2 of Exserohilum infection, which demonstrate the capability of these 2 genera to cause invasive as well as "allergic" disease. As noted previously, it is likely that all of the cases of "Helminthosporium" and Drechslera infections reported in the literature were caused by Bipolaris or Exserohilum. Infections due to these 2 genera are probably more common than previously recognized. They should be included in the differential diagnosis of central nervous system and disseminated fungal disease, sinusitis, keratitis, peritonitis associated with continuous ambulatory peritoneal dialysis, and allergic bronchopulmonary disease. These various entities have distinct histopathologic characteristics. With disseminated disease in the immunocompromised patient, the most frequent findings are acute inflammation with prominent vascular invasion, thrombosis, and infarction. In contrast, granulomatous inflammation and leukocytoclastic vasculitis are seen in meningoencephalitis caused by these fungi. The histologic features of allergic bronchopulmonary disease and sinusitis are similar. A chronic inflammatory infiltrate of lymphocytes, plasma cells and eosinophils within edematous granulation tissue is found in addition to squamous metaplasia and thickening of the basement membrane. Infections caused by Bipolaris/Exserohilum and Aspergillus show many clinical and pathologic similarities despite the lack of taxonomic relationship between these fungi. Both cause disseminated disease in immunocompromised patients that is characterized by tissue necrosis and vascular invasion. Both cause central nervous system disease, osteomyelitis, and sinusitis and are associated with allergic bronchopulmonary disease. Sinusitis, the most common form of disease caused by Bipolaris and Exserohilum, occurs in otherwise healthy patients with nasal polyposis and allergic rhinitis. Although pathologic evidence of bone invasion may not be found, there frequently is radiographic evidence of invasive disease. Most patients who are treated initially with surgical debridement and amphotericin B have apparently been cured. However, longer follow-up will be necessary in these patients. Amphotericin B appears to be the treatment of choice for invasive infections caused by Bipolaris/Exserohilum species. Ketoconazole and other imidazole derivatives may also be effective in certain of the disease entities caused by these black moulds; however, their role has yet to be defined.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
44.
Maternal and Child Health Journal - The aim of this study was to estimate the association between individual and contextual characteristics related to maternal work and exclusive breastfeeding...  相似文献   
45.
Monkeypox is a rare zoonotic disease caused by infection with the monkeypox virus. The disease can result in flu-like symptoms, fever, and a persistent rash. The disease is currently spreading throughout the world and prevention and treatment efforts are being intensified. Although there is no treatment that has been specifically approved for monkeypox virus infection, infected patients may benefit from using certain antiviral medications that are typically prescribed for the treatment of smallpox. The drugs are tecovirimat, brincidofovir, and cidofovir, all of which are currently in short supply due to the spread of the monkeypox virus. Resistance is also a concern, as widespread replication of the monkeypox virus can lead to mutations that produce monkeypox viruses that are resistant to the currently available treatments. This article discusses monkeypox disease, potential drug targets, and management strategies to overcome monkeypox disease. With the discovery of new drugs, it is hoped that the problem of insufficient drugs will be resolved, and it is not anticipated that drug resistance will become a major issue in the near future.  相似文献   
46.
Two patients with the syndrome of proper name anomia were investigated. Both patients were only able to produce around 50% of the names of contemporary celebrities, but performed significantly better on a task calling for naming of historical figures. The names of relatives and friends were spared in one patient, while the other retrieved names of people known since childhood much better than those of people familiar to him since the age of 25. Geographical names, names of monuments and masterpieces were preserved. The above dissociations are taken to imply that in moderately impaired patients, a temporal gradient effect concurs to modulate the severity of the naming block.

A similar impairment was found in both patients when they attempted to retrieve or relearn familiar telephone numbers. This finding suggests that the core of the disorder resides in the inability to gain access to words used to identify a single entity, regardless of whether they belong to the class of proper or common names.  相似文献   

47.
Pheochromocytomas and functioning paragangliomas are rare tumors arising from the primitive neural crest, and found in the adrenal medulla or elsewhere within the sympathetic paraganglion axis. Clinical symptoms are related to catecholamine production or less frequently to dopamine or other neuropeptides secretion. Malignant pheochromocytomas are very rare tumors comprising between 5-35%, but this value is uncertain because the usual criteria for malignancy, such as mitotic activity, nuclear pleomorphism, are not suitable to discern benign from malignant pheochromocytomas. A specific diagnosis of malignancy requires evidence of invasion of the adjacent organs and the occurrence of metastases. Personal experience is presented with 92 patients affected by: adrenal pheochromocytomas (51 cases), cervical paragangliomas (32 cases), and extra-adrenal paragangliomas (9 cases). Malignant forms were observed in a 23-year-old young woman affected by malignant pheochromocytoma with lymphatic para-aortic metastases (1.9%), and in 2 patients affected by cervical paragangliomas (1 CBT, 1 VBT) with lymph nodal metastases. Careful follow-up of all patients with measurement of the urinary catecholamine is necessary to detect metachronous neoplasm and later metastases, identified with RMN and 131I-MIBG scintiscan.  相似文献   
48.
Clinical pharmacokinetics of tacrolimus in heart transplant recipients   总被引:6,自引:0,他引:6  
We report pharmacokinetic data on tacrolimus in 14 heart transplant patients (2 women, 12 men). The median age and the median body weight were 55.5 years (range, 23-61 years) and 67.0 kg (55-79 kg), respectively. All patients were maintained on a triple-drug protocol (tacrolimus, azathioprine, and prednisone), with a 7-day antithymocyte globuline induction. The first tacrolimus dose, administered orally 1 to 5 days posttransplant, ranged from 0.03 to 0.4 mg/kg (median = 0.052 mg/kg). The maintenance dose ranged from 0.03 to 0.13 mg/kg/day (administered in two equal doses) to achieve blood levels of 5 of 20 ng/ml, as determined by a microparticle enzyme immunoassay (MEIA). Whole blood samples were drawn just before, at 0.5 hour, and at 1, 2, 3, 4, 6, 8, 10, and 12 hours after the administration of the first dose; trough levels were measured thereafter.The mean oral clearance (CL/F) and apparent volume of distribution (Vd/F) averaged 0.21+/-0.08 L/hour/kg and 2.4+/-0.8 L/kg while the half-life averaged 8.7+/-3.5 hours. Tacrolimus accumulation index during chronic therapy (Rac = Cmin(steady state)/Cmin(first dose) normalized to the same dose) averaged 1.3. Eighty-eight percent of the trough blood levels measured in our patients were within 5 and 20 ng/ml. The incidence of rejection in the study population was extremely low: a prevalence of grade 2 rejection or more, of 0.4+/-0.8 episodes/ patient was observed after a follow-up period of 8.8+/-2.2 months. Only one patient experienced severe renal toxicity, probably because of his preoperative precarious hemodynamic status. Pharmacokinetic data suggest that maintenance tacrolimus daily dose should be equal to 0.1 mg/kg/day to obtain trough blood concentrations of approximately 10 ng/ml. Inter- and intra-patient variability of tacrolimus blood concentration should be expected and justify careful monitoring.  相似文献   
49.
Fifty-three inoperable lung cancer patients were treated with radiotherapy combined with immunostimulation with BCG. A good response was obtained in 30 patients (56%); the results were not significantly different than those obtained with a control group of 50 lung cancer patients matched by age, sex and stage of the disease (24 out of 50 equals 46%). These short-term results were compared with the immunologic "status" of patients evaluated before treatment by the parameters monitoring in vivo and in vitro delayed type hypersensitivity. The good response to therapy was documented in a higher percentage of patients with positive skin tests to recall and standard antigens and with normal values of lymphocyte transformation with PHA and Rosette E-forming cells, in comparison with patients with low levels of immunocompetence. An impairment of the cell-mediated immune response was found after combined therapy, presumably due to radiotherapy. BCG was not able to restore the patient's immunocompetence, no effect on host's immune reactivity was demonstrated. As regards humoral immunity, the patients with low levels of IgG before treatment (12/14) showed a good response.  相似文献   
50.
High circulating concentration of insulin-like growth factor-I (IGF-I) and low circulating concentration of IGF binding protein-3 (IGFBP-3) have been associated with increased risk for breast, prostate, and colorectal cancers. Building on previous work in the Multiethnic Cohort (MEC) showing significant differences in IGF-I levels across racial/ethnic groups, we investigated which lifestyle and dietary factors are associated with levels of IGF-I and IGFBP-3 in a random sample of 1,000 MEC participants, which included Native Hawaiian, African American, Japanese, Latino, and White men and women. Crude analyses confirmed the existence of differences in protein levels with race/ethnicity, sex, age, and body size. Reproductive, physical activity, smoking, and diet variables had less consistent effects. In multivariate analyses, IGF-I levels were lower and IGFBP-3 were higher in females versus males. IGF-I and IGFBP-3 declined with increasing age in both genders. Women in the highest quartile of body mass index showed depressed IGF-I and IGFBP-3 levels; in men, height was significantly positively associated with both proteins. In women, alcohol was directly associated with IGFBP-3. Both proteins were lowest among female Latinos. IGF-I was highest among female African Americans. In men, IGFBP-3 was lowest among African Americans. Overall, although these factors were statistically significant determinants of IGF-related protein levels, they did not explain much of the variation in these levels. A positive correlation was found between IGF-I levels (ng/mL) and colon cancer incidence rates (per 100,000) within the MEC by race/ethnicity for both sexes but not for either breast or prostate cancer.  相似文献   
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