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1.
The use of the monoclonal antibody Ki-67 in the identification of proliferating cells: application to surgical neuropathology 总被引:6,自引:0,他引:6
In order to test its potential application to surgical neuropathology, the monoclonal antibody Ki-67 was used to demonstrate immunohistochemically the proliferating cells in 40 neoplasms of the nervous system. The antibody, which reacts with a nuclear protein expressed in the G1, G2, S, and M phases of the cell cycle, was demonstrated in frozen sections of all lesions. The highest incidence of stained nuclei was found in a metastatic carcinoma (57%). The percentage of stained cells in gliomas was in general agreement with the histologic grade and known biologic behavior of the lesions, ranging from 0.6% in a pilocytic astrocytoma to 12.4% in a glioblastoma multiforme. In the fibrillary astrocytic neoplasms of low cellularity, there were good correlations between the percentages of stained cells and the degrees of nuclear pleomorphism and chromatin density. In meningiomas, schwannomas, and a cerebellar hemangioblastoma, the fractions of labeled nuclei were less than 1%. The percentage of stained cells in pituitary adenomas showed considerable variation among the four cases (0.2-1.5%), the biologic significance of which is unknown. In four of the above cases, Ki-67 staining was performed on air-dried squash preparations with excellent visualization of immunoreactive nuclei. In one case, a hemangioblastoma, no stained nuclei were seen. The results confirm that Ki-67 staining is technically suitable as a diagnostic method, with good correlations between frozen sections and smear preparations. Determination of the replicating cell fraction could become an important additional criterion to predict the biologic behavior of nervous system neoplasms. 相似文献
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A. M. Raschke A. E. C. Burger 《Archives of environmental contamination and toxicology》1997,32(1):42-49
A preliminary study undertaken by the CSIR in July 1993
on the health effects of aerial crop spraying of pesticides in the Vaalharts
irrigation area in South Africa indicated that potential health risks could
exist for the inhabitants of this area. An extensive scientific health risk
assessment and epidemiological study to determine the actual health risks, is
very expensive and requires medical and financial justification. The aim of
this study was to develop a theoretical health risk model, which could be
used as a predictive tool to determine as accurately as possible from the
data available if a complete scientific health risk assessment study is
justified. The actual amounts of pesticides sold in the Vaalharts area by two
major pesticide manufacturers were used to perform a theoretical health risk
assessment. The risks were assessed by making use of RISK*ASSISTANT, a
computer modeling system and chemical database. The United States
Environmental Protection Agency's (EPA) health risk model was applied to
the data to identify the hazards, assess the exposures and dose response, and
characterize the risks. Three exposure scenarios, namely, the ingestion of
food and water and the inhalation of air were evaluated. The method used to
calculate the risks varied according to the type of health hazard and the
results were characterized accordingly. The acute health effects due to
exposure to pesticides are well known and the risks are easy to determine.
However, the risks associated with chronic health hazards were more difficult
to calculate. For this reason a ranking model was developed which made use of
a point scoring system. This model highlights those pesticides which have the
greatest possibility of causing chronic health effects. From the results it
can be concluded that very large amounts of pesticides are used in the
Vaalharts area and that the community might be at risk to chronic health
effects. Although the theoretical health risk assessment model was
successfully used in this study, its effectiveness as a predictive tool still
has to be proven by a complete scientific study.
Received: April 1996/Revised: 21 July 1996 相似文献
5.
M J Coppes M F Tournade J Lemerle S Weitzman A Rey D Burger M Carli P A Vo?te 《Cancer》1992,69(11):2721-2725
The International Society of Pediatric Oncology (SIOP) recommends preoperative treatment in the management of eligible patients with Wilms' tumor. Until 1980, children younger than 12 months of age (infants) at diagnosis had been excluded from the SIOP trials. SIOP 6, conducted from 1980 to 1987, was the first SIOP study to include infants older than 6 months of age. This retrospective analysis of 145 infants registered to SIOP 6 demonstrates that in infants older than 6 months and having favorable histology (FH), a two-drug preoperative chemotherapy (CT) regimen of 4 weeks significantly ameliorated stage distribution as determined at delayed surgery but did not affect a good outcome. However, the CT dose utilized in SIOP 6 resulted in an unacceptable toxicity in this age group, and SIOP 9, the new SIOP study of Wilms' tumor, recommends a reduced dose of CT in infants. Preoperative CT is not recommended in infants younger than 6 months of age. Specifically, the high incidence (29%) of mesoblastic nephroma in this age group does not justify such an approach. Histopathologic diagnosis should be obtained in these patients before any treatment. 相似文献
6.
Judith A. MacNaughton Mohan L. Bangah' Philip I. McCloudt Henry G. Burger 《Clinical endocrinology》1991,35(4):341-346
OBJECTIVE: Normal elderly men are reported to have decreased testicular function despite elevated gonadotrophin levels. We wished therefore to determine if changes in testicular function occur over the age range 19-60 years. DESIGN: Single fasting blood samples were obtained between 0800 and 0900 h. PATIENTS: Working men in a large industrial company between the ages of 19 and 60 years participated in the study. MEASUREMENTS: FSH, serum immunoreactive inhibin and total testosterone were measured, the latter two as measurements of Sertoli and Leydig cell function respectively. RESULTS: The mean baseline serum immunoreactive inhibin level was significantly lower in men from the older age groups, 31-40 years (479 U/l), 41-50 years (439 U/l) and 51-60 years (415 U/l) than in men from the youngest age group, 21-30 years (613 U/l) while serum FSH was higher in men from the older age groups, 41-50 years (3.7 IU/l) and 51-60 years (6.1 IU/l) than in men from the youngest age group, 21-30 years (2.6 IU/l). There appears to be a change in both FSH and inhibin production, consistent with a primary decline in testicular function. There was no significant difference in testosterone levels between the older age group, age 51-60 years and the younger age group, age 21-30 years. However, testosterone levels were significantly lower in the 41-50 year age group, when compared with the 21-30 year, this significance levelling out at about age 45 years. CONCLUSION: The data are consistent with the hypothesis that immunoreactive inhibin reflects inhibin bioactivity, and that inhibin plays a role in the feedback control of FSH secretion in men. 相似文献
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A S Alberts L Schoeman W Burger F Greef G Falkson 《American journal of clinical oncology》1992,15(1):35-36
Thirty-five patients with advanced epidermoid carcinoma of the esophagus were treated with 5-fluorouracil (5-FU) 425 mg/m2 and leucovorin 20 mg/m2, day 1-5 every 28 days. Six patients had a partial response (95% confidence limit, 7-35%) with a median response duration of 32 weeks. The median survival time of the patients on study was 14 weeks. The toxicity was acceptable, with only two patients experiencing severe hematologic toxicity and one patient experiencing severe nausea and vomiting. The addition of leucovorin at this dose level in this population of patients with advanced disease does not appear to enhance the activity of 5-FU for patients with squamous cell cancer of the esophagus. Since only a small percentage of patients experienced significant toxicity, a higher response rate could be achieved in patients treated with the maximally tolerated dose. 相似文献
9.
Improved cytosolic free calcium mobilization and superoxide production in bicarbonate-based peritoneal dialysis solution 总被引:1,自引:0,他引:1
Dobos G; Burger M; Kuhlmann J; Passlick-Deetjen J; Schollmeyer P; Bohler J 《Nephrology, dialysis, transplantation》1997,12(5):973-977
Background. Intraperitoneal phagocytes play an
important role in local host defence to prevent CAPD peritonitis. The
intracellular calcium [Ca2+]i is thought to be
involved in the regulation of various cell functions. This study therefore
investigates the effect of lactate-based dialysis solution (LBDS) and
bicarbonate-based dialysis solution (BBDS) on cytosolic free calcium
mobilization and superoxide production (SP) as important steps in signal
transduction and bacterial killing. Methods. We
studied changes in [Ca2+]i and SP following
stimulation with N-formyl-methionyl-leucyl-phenylalanine (fMLP) in
polymorphonuclear neutrophils (PMNs) incubated in either LBDS-pH 5.2, LBDS
adjusted to pH 7.4, 1:10 diluted spent and fresh LBDS or BBDS-pH 7.4 with
different glucose concentrations, comparing the data with cells treated
with Hanks buffer (HBSS) pH 7.4 as control. To elucidate the effect of
glucose and lactate PMNs were additionally incubated in HBSS-pH 7.4,
containing glucose (HBSS-Glu-pH 7.4) or lactate (HBSS-Lact-pH 7.4) in the
same concentrations as contained in CAPD solutions and tested as above.
PMNs were isolated from healthy blood donors and incubated with dialysis
solution 10 min prior to stimulation with fMLP.
Results. [Ca2+]i mobilization
and SP were completely inhibited in PMNs incubated in LBDS pH 5.2. pH
adjustment of LBDS to 7.4 and 1:10 dilution of spent and fresh LBDS
corrected some of the suppression of the calcium influx and superoxide
production. BBDS pH 7.4, however, preserved physiological cell function
significantly better at low (1.5 and 2.3%) glucose concentrations.
Conclusion. In comparison to conventional
lactate-based dialysis solution, pH adjusted and 1:10 diluted LBDS,
bicarbonate-based dialysis solution is more biocompatible since it
preserves significantly better neutrophil cell functions. 相似文献
10.
(B10.A x A/WySn)F1 mice, infected with the Friend virus (FV) complex, were used as a predictive therapeutic model for AIDS. These infected mice exhibit many of the viral and immunologic manifestations of AIDS. Bropirimine (2-amino-5-bromo-6-phenyl-4[3H]pyrimidinone, ABPP) is an immunomodulating compound which has been shown to inhibit other viral infections. Oral (per os treatment) dosages of ABPP ranging from 50 to 400 mg/kg/day for 3 days resulted in increased numbers of infectious centers in the infected mice and increased splenomegaly and percentage of Ig+ (B cells) in spleens of infected and uninfected mice. Decreased percentages of total Thy-1.2+ (total T) cells and L3T4+ (T-helper) cells were seen in both uninfected and infected mice and a slightly decreased percentage of Ly-2+ (T-suppressor/cytotoxic) cells was observed in spleens of the infected mice. No effect on Ly2+ cells in spleens of uninfected mice was found. Intraperitoneal injection, single or multiple, of 20-200 mg/kg ABPP prior to FV injection resulted in increased spleen weights but had no effect on numbers of infectious centers in the spleens or on FV antibody titers in the plasma. Intraperitoneal treatment of uninfected mice with ABPP resulted in slight or no changes in percentages of Thy-1.2+, L3T4+ and Ly-2+ cells. Mice receiving multiple exposures of ABPP had an increase in percentage of splenic B cells and a depressed response to the T cell mitogen PHA. Treatment with ABPP induced the production of interferon (IFN); however, a state of hyporesponsive IFN production was seen following multiple administrations of ABPP. These data suggest that the immunomodulator ABPP may have an enhancing effect on this retroviral disease. 相似文献