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排序方式: 共有416条查询结果,搜索用时 32 毫秒
1.
Effective prevention of recurrent urinary tract infections (UTIs) and possible acute pyelonephritis is of major importance during pregnancy. During 39 pregnancies, 33 women with a history of recurrent UTIs (and, in some instances, pyelonephritis) received postcoital prophylaxis consisting of a single oral dose of either cephalexin (250 mg) or nitrofurantoin macrocrystals (50 mg). While 130 UTIs occurred during a mean observation period of 7 months before prophylaxis, only a single UTI occurred during pregnancy after prophylaxis; this difference was highly significant. Thus the use of one of these effective regimens is strongly recommended for any pregnant woman with a history of recurrent UTIs. The treatment's effectiveness can be explained by two features of the two antibacterial agents involved: both reach high bactericidal concentrations in the urinary tract and induce no (or minimal) resistance in the introital gram-negative bacterial flora. 相似文献
2.
Infected renal stones can be treated by extracorporeal shock wave lithotripsy but it still is not clear whether successful stone fragmentation and the disappearance of all macroscopic stone fragments guarantee eradication of the infection. Therefore, a prospective study was done in 135 patients with renal or upper ureteral stones associated with persistent urinary tract infection. The urinary infection was localized in each patient by bilateral ureteral catheterization. Upper tract infection in the kidney containing the stone was found in 75.6 per cent of the cases. A total of 94 patients completed treatment with extracorporeal shock wave lithotripsy and were followed for 3 to 16 months (mean followup 6.4 months). A marked correlation between the incidence of residual macroscopic stone fragments and the presence of persistent infection was noted. Of the 51 patients who became free of stones 48 (94 per cent) had sterile urine. Only 3 of the 51 patients had persistent infection in the treated kidney despite complete disappearance of the stones. In 45 of the 59 patients with stones smaller than 2 cm. (76 per cent) the infection was eradicated, whereas of the 35 with larger stones the urine became sterile in only 13 (37 per cent). We conclude that extracorporeal shock wave lithotripsy can be endorsed for treatment of small infected stones but it is inadequate for treatment of stones larger than 2 cm. unless combined with percutaneous nephrolithotripsy or chemical dissolution of the residual infected fragments. 相似文献
3.
Arenaviruses: Cellular Response to Long-Term In Vitro Infection with Parana and Lymphocytic Choriomeningitis Viruses 总被引:4,自引:2,他引:4
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L. D. Staneck R. S. Trowbridge R. M. Welsh E. A. Wright C. J. Pfau 《Infection and immunity》1972,6(4):444-450
Persistent infections were established in suspension cultures of BHK21/13S cells with both Parana and lymphocytic choriomeningitis viruses. Four generations after infection with either virus, more than 90% of the cells scored as infective centers, with concomitant peaks in extracellular virus yields. In both cultures the synthesis of detectable plaque-forming units (PFU) ceased about the 50th generation postinfection, and this condition was maintained until the 350th cell generation when the cultures were discontinued. The generation time of each culture was identical to that of uninfected parent controls, and at no time were cytopathic effects evident. In spite of the absence of infectivity, over 90% of the cells sampled at various times contained viral antigen demonstrable by immunofluorescence. When either of these persistently infected cell lines was substituted for normal cells in the standard plaque assay, very low efficiencies of plating were observed for homotypic and heterotypic viruses. Plaque formation by several heterologous viruses was virtually unaffected. The mechanism of homotypic plaque exclusion in both cell lines was shown to occur beyond the virion adsorption stage. The original infecting virus genome persisted in both cell lines after standard virus was no longer detectable. This was shown with the lymphocytic choriomeningitis virus-infected cells after storage in liquid nitrogen. After thawing, such cells were found to synthesize standard virus for a brief period. Although the Parana virus-infected cells did not behave this way, the growth medium from these cells would initiate PFU synthesis in normal cells within 36 hr after infection. 相似文献
4.
Schwärzler P Zech H Auer M Pfau K Göbel G Vanderzwalmen P Zech N 《Human reproduction (Oxford, England)》2004,19(9):2097-2102
BACKGROUND: Retrospective cohort study to evaluate differences in outcome when embryo transfer was performed either on day 2-3 (cleavage stage, CS-group) or on day 4-5 (blastocyst stage, BS-group). METHODS: A total of 1259 consecutive cycles yielding 500 live born babies performed at a single centre in Bregenz, Austria, were included. Main outcome measures were implantation and (multiple) pregnancy rates and neonatal outcome including birth defects. RESULTS: Total Pregnancy rate was 44% vs 28% (P < 0.001) and the total 'take home baby rate' was 37% vs 22% in the BS-group and the CS-group, respectively. Rate of multiple gestations (34% vs 17%, P = 0.001) was significantly higher among the BS-group, resulting in a higher rate of preterm deliveries < 36 weeks (26% vs 17%, P = 0.045). Female factor causing infertility (40% vs 21%, P < 0.001) was significantly higher among the BS-group. For the CS-group, rate of singleton pregnancies (83% vs 66%, P = 0.001) and idiopathic cause of infertility (34% vs 22%, P = 0.012) were significantly higher. No statistically significant differences were found in sex, Caesarean section rate, Apgar score and umbilical artery pH-values, total mean birth weight, admission rate to intensive care unit, days of hospitalization and number of minor and major birth defects. CONCLUSIONS: Our data suggest that blastocyst transfer may lead to a higher pregnancy rate with an overall better take-home baby rate (THBR) at the cost of higher rates of multiples and preterm deliveries. 相似文献
5.
6.
Käsmann-Kellner B Weindler J Pfau B Ruprecht KW 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》1999,213(3):200-205
BACKGROUND: The mucopolysaccharidoses (MPS) are an inhomogeneous group of disorders of errors in the carbohydrate metabolism with severe ocular involvement (corneal opacification, retinal degeneration, optic atrophy). PATIENT PRESENTATION: We report on a boy aged 12 years, with Morquio A (MPS IV A) syndrome. Ocular findings: progressive pseudoexophthalmus due to shallow orbits, increasing corneal stromal clouding, intermittent dissociated manifest nystagmus of the left eye, nyctalopia. Visual acuity OD cc = 0.16, OS cc = 0.05. Electrophysiology: changes suggesting a symptomatic tapetoretinal degeneration and optic atrophy. TREATMENT AND COURSE OF DISEASE: OS: perforating keratoplasty. Postoperative improvement of visual acuity to 0.25 for nearly a year, followed by progressive reopacification of the corneal graft. Both eyes: progressive signs of tapetoretinal degeneration and optic atrophy. Visual acuity now reduced to OD 0.05, OS 0.1. CONCLUSIONS: Success of a keratoplasty is limited by (1) reopacification of the cornea, (2) visual impairment due to (a) retinal degeneration and (b) optic atrophy. The indication for perforating keratoplasty has to be thought about very carefully in these multimorbid patients. In our patient, beside progressive visual impairment there is a progressive deafness which dominates his social and school life. Attending school is severely complicated by the double handicap. Perforating keratoplasty enabled the boy to attend a school for physically handicapped without a special low-vision care for another year. Progressive visual loss without further treatment options now renders optical and electronic low-vision aids necessary. Although the time of improved visual acuity lasted less than a year, we think patients with a life expectancy of less than 20 years should have every possible improvement of their situation - even if it does not last permanently. We therefore propose perforating keratoplasty in spite of insufficient long-term results. 相似文献
7.
Carcinogenicity and DNA adduct formation observed in ACI rats after long-term treatment with madder root, Rubia tinctorum L 总被引:1,自引:0,他引:1
Madder root, Rubia tinctorum L., is a traditional herbal medicine used
against kidney stones. Recently we reported that lucidin, a
hydroxyanthraquinone derivative present in this plant, is mutagenic in
bacteria and mammalian cells. We also demonstrated the formation of DNA
adducts in tissue culture and mice after treatment with this compound. To
elucidate the possible carcinogenicity of madder root, three groups of male
and female ACI rats received either a normal diet or a diet supplemented
with 1 or 10% drug for a total period of 780 days. Weight gain and
morbidity were not different among the three groups. Non- neoplastic
lesions related to the treatment were evident in the liver and kidneys of
both sexes. Moreover, dose-dependent increases in benign and malignant
tumour formation were observed in the liver and kidneys of treated animals.
32P-post-labelling analysis showed an increase in the overall level of DNA
adducts observed in the liver, kidney and colon of rats treated with 10%
madder root in the diet for 2 weeks. HPLC analysis of 32P-labelled DNA
adducts revealed a peak co-migrating with an adduct obtained after in vitro
treatment of deoxyguanosine-3'- phosphate with lucidin. These observations
suggest that the use of madder root for medicinal purposes is associated
with a carcinogenic risk.
相似文献
8.
The Center for Environmental Health Sciences (CEHS) Conference entitled “Directions and Needs in Asbestos Research: New Insights” was held at the University of Montana in Missoula on July 28 and 29, 2005. Researchers, physicians, health care workers, and federal agency representatives from around the country met for a cross-disciplinary exploration of many issues related to asbestos research. Topics included community and psychosocial issues in biomedical research, asbestos exposure assessment, assessment and mechanisms of asbestos-related diseases, and new research directions. This meeting report is a summary of the conference presentations, and of the topics identified for future research directions. This conference was a follow-up to one hosted by the CEHS in June 2002, and continued to take advantage of opportunities to work with a unique population in Libby, MT, where significant asbestos exposures have occurred due to the mining of asbestos-contaminated vermiculite. The goals of this conference were to bring together experts from diverse fields to identify progress made since the last conference and to develop new research avenues that would allow us to address the research needs in emerging asbestos-exposed populations. Participants indicated that these objectives were met, and expressed enthusiasm for follow-up conferences, tentatively planned for the summer of 2007, to maintain the dialog that has been established regarding directions and needs in asbestos research. Selected papers from the conference are presented in this issue of Inhalation Toxicology. 相似文献
9.
Manuelle Medizin - Der Begriff „funktionell“ wird einerseits in der inneren Medizin für Störungen in den Bereichen Gastrointestinaltrakt, Atmungssystem, Herz-Kreislauf-System... 相似文献
10.