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91.
Dural repair using acellular human dermis: experience with 200 cases: technique assessment 总被引:47,自引:0,他引:47
Warren WL Medary MB Dureza CD Bellotte JB Flannagan PP Oh MY Fukushima T 《Neurosurgery》2000,46(6):1391-1396
OBJECTIVE: Many craniotomies require a watertight dural closure. When primary dural repair is not possible, a graft is necessary. Autograft material is not always easily accessible or available, necessitating the use of other material. We performed 200 craniotomies using an acellular human dermal graft (AlloDerm; LifeCell Corp., The Woodlands, TX) to determine its suitability as a dural substitute. METHODS: From June 1996 through March 1998, all patients at Allegheny General Hospital who required a dural substitute graft and in whom autograft harvest was impractical or impossible received the acellular dermal autograft. The running suture technique was used to form a watertight seal. RESULTS: After follow-up for a minimum of 1 year, seven patients have required subsequent surgery. Three patients developed cerebrospinal fluid leaks that were repaired without removing the dermal graft. Four patients developed wound infections that required debridement. In each patient, the graft seemed to be uninvolved in the infectious process and was left in place. The patients were administered antibiotics postoperatively, and there have been no recurrent infections. No adhesion formation or scarring was noted around or underneath the graft in any patient. CONCLUSION: AlloDerm is a reasonable alternative to the available dural graft materials. Its handling characteristics are similar to those of dura, it is biologically inert, and it does not produce adhesion formation. 相似文献
92.
Glenn Liu David R Gandara Primo N Lara Derek Raghavan James H Doroshow Przemyslaw Twardowski Philip Kantoff William Oh KyungMann Kim George Wilding 《Clinical cancer research》2004,10(3):924-928
PURPOSE: Flavopiridol is a cyclin-dependent kinase inhibitor with preclinical activity against prostate cancer cell lines. A Phase II trial was conducted to determine the activity of flavopiridol in patients with metastatic hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: A total of 36 patients was enrolled from several institutions and treated with a 72-h continuous infusion of flavopiridol every 14 days at the eventual starting dose of 40 mg/m(2)/day. Dose escalation up to 60 mg/m(2)/day was permitted if no significant toxicity was observed. Responses were assessed every 12 weeks. Only those patients completing four courses of the 72-h infusion were considered evaluable for response because the primary objective was to determine progression-free survival at 6 months given the cytostatic nature of the agent. RESULTS: This study was conducted in a two-stage fashion. During the first stage, at least 20 evaluable patients needed to be enrolled to assess response. There were 22 of 36 patients evaluable for response. No objective responses were observed. Only 4 patients had stable disease for 16, 26, 29, and 48 weeks, respectively, stopping the trial by design as only 3 of 22 (14%) of the patients met the 6-month progression-free survival end point. The most common toxicities were diarrhea (grade 1 and 2) and nausea, although some grade 3 and 4 diarrhea (11 and 6%, respectively) were evident. CONCLUSIONS: Flavopiridol has disappointing single-agent activity in hormone-refractory prostate cancer when administered at this dose and schedule. Its use in prostate cancer should be reserved for evaluation in combination therapies or alternative schedules. 相似文献
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96.
Proliferative lesions of oviduct and uterus in CD-1 mice exposed prenatally to tamoxifen 总被引:1,自引:3,他引:1
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after
surgery and as a chemopreventive agent in women of child-bearing age.
However, TAM therapy has been shown to result in an increased incidence of
endometrial carcinoma in women. The present study was designed to
investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g.
to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their
female offspring. Progressive proliferative hyperplasia of the oviduct was
frequently seen in TAM-exposed offspring, reaching 100% incidence by 52
weeks in both treatment groups. These females also developed progressive
proliferative uterine lesions, including moderate/severe cystic endometrial
hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78
weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while
leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell
tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest
a strong association between transplacental TAM and reproductive tract
abnormalities in female CD-1 mice.
相似文献
97.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
98.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
99.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective. 相似文献
100.