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171.
172.
Edward W. Lipkin M.D. Ph.D. Susan M. Ott Gordon L. Klein Leonard J. Deftos 《Calcified tissue international》1990,47(2):75-81
Summary Bone gamma-carboxyglutamic acid containing protein (BGP) has been utilized effectively as a serum marker of bone turnover
in healthy normals and in individuals with a variety of metabolic bone disorders including postmenopausal osteoporosis and
Paget's disease. The utility of this serum marker in other bone disorders, including that associated with the maintenance
of patients on long-term parenteral nutrition, still requires definition. Because of our interest in this clinical syndrome
and the availability of serum and of bone formation rates (BFR) measured directly from double tetracycline labeling in 11
long-term parenteral nutrition patients, we measured BGP levels in these patients and attempted to correlate this measure
with BFR. Serum vitamin D metabolites, immunoreactive parathyroid hormone (PTH), and alkaline phosphatase (alk phos) were
also measured. Serum BGP was only weakly and not significantly correlated (r=0.24, p=NS) with bone formation rate for the
group as a whole. However, in a subgroup of 10 patients without hyperparathyroidism, there was strong and significant correlation
(r=0.81,P<0.01) between BGP and BFR. There was also a strong correlation between bone formation rate and serum 1,25 dihydroxyvitamin
D [1,25(OH)2D] levels (r=0.89,P<0.01, n=11). The mechanism of this association could not be established. A correlation of borderline significance was observed
between bone formation rate and serum alk phos (r=0.60,P=0.05, n=11). The current data suggest that additional studies may help to more fully define the utility of serum measurements
in quantifying bone dynamics in parenteral nutrition patients, and that measures of vitamin D metabolites, BGP, and alk phos
may prove useful. 相似文献
173.
Christine A. Ellis Susan F. Brooks Gavin Brooks A. Tudor Evans Nicholas Morrice Fred. J. Evans Alastair Aitken 《Phytotherapy research : PTR》1987,1(4):187-190
The sapintoxins are a series of naturally occurring fluorescent phorbol esters with a range of selective biological activities (e.g. pro-inflammatory but non-tumour promoting). Their ability to activate protein kinase C (PKC) in vitro has been studied. Both tumour promoting and non-promoting phorbol derivatives activate the enzyme in vitro at low concentrations. 12-deoxyphorbol-13-phenylacetate-20 acetate (DOPPA) acts as a partial agonist in the activation of protein kinase C. Structurally distinct phorbol esters may therefore preferentially activate different forms of protein kinase C. α-sapinine, a biologically inactive compound, binds to protein kinase C without stimulating the enzyme and prevents subsequent activation by phorbol esters such as 12-O-tetradecanoyl phorbol-13-acetate (TPA). 相似文献
174.
175.
176.
177.
Susan K. Hummel DDS Victoria Marker PhD Larry Pace DDS Michael Goldfogle DDS 《The Journal of prosthetic dentistry》1997,77(6):568-572
Statement of problem. Controversy surrounds the use of hydrofluoric acid to prepare precementation surfaces of indirect composites.Purpose. This study was conducted to compare effects of combining hydrofluoric or orthophosphoric acid with microetching as precementation treatments.Material and methods. Nine specimens of three composite materials were prepared to simulate heat-cured indirect restorations. The specimen surfaces were prepared with one of three treatments. Adhesive Bond II and Twinlook cements were used to bond a phosphoric acid-etched disk of P50 to the treated surface. Analysis of variance and Scheffé tests were used to assess the bond strength data. Scanning electron microscopy and microscopic analysis of the fractured and treated surfaces were also performed.Results. Bond strengths for all surface treatments did not significantly differ. Hybrids had a higher bond strength with etching than microfills, and mechanical roughening produced the greatest bond strengths with microfills. Microetching with orthophosphoric acid produced higher bond strengths than microetching with hydrofluoric acid on hybrids.Conclusions. Acid etching alone is not sufficient to produce effective bond strengths, and hydrofluoric acid treatments are detrimental to the resin composite. (J Prosthet Dent 1997;77:568-72.) 相似文献
178.
Salvatore J. A. Sclafani M.D. Michael Herskowitz M.D. Susan Rachlin M.D. Stanley Z. Trooskin M.D. 《Emergency radiology》1995,2(6):380-383
Traumatic communications between the hepatic artery or its branches and the portal vein or its tributaries usually are clinically
occult until the late sequelae of portal hypertension, such as esophageal and mesenteric varices, ascites, or congestive heart
failure, become manifest. The authors describe the early diagnosis of such a lesion by computed tomography. The CT findings
included a hepatic hematoma and, more significantly, diffuse thickening of the small and large bowel wall. This thickening
represents vascular congestion of the bowel caused by acute portal hypertension prior to the development of decompressing
portal collateral circuits.
When this CT finding is not associated with other signs of intestinal ischemia or infarction, it should suggest portal hypertension
and lead to arteriography for diagnosis and therapy of arterioportal fistula. 相似文献
179.
Theresa Widrich M.D. Alexander W. Kennedy M.D. Teresa M. Myers M.D. William R. Hart M.D. Susan Wirth B.S.N. 《Gynecologic oncology》1996,61(3):304-308
Objective: To retrospectively review the management of adenocarcinomain situof the uterine cervix, to determine the outcome of conization versus hysterectomy, and to compare the results achieved by different methods of conization. Methods: We performed a retrospective pathology and chart review of 46 patients with cervical adenocarcinomain situfrom January 1980 to October 1994. Results: Nine patients were managed during the first half of the study period and 37 were managed in the second half. The mean age of patients was 38.4 years (range 25–72). Forty-five of 46 patients were diagnosed as a result of an abnormal Pap smear, although only 19 smears indicated adenocarcinomain situor other glandular abnormalities. Cold knife conization resulted in a 33% rate of positive margins for adenocarcinomain situcompared to 50% for large loop excision of the transformation zone (LLETZ). Among 24 conservatively managed patients with negative conization margins, there have been 2 (8.3%) recurrences of adenocarcinomain situ.Among patients not undergoing hysterectomy as definitive treatment, 1 of 18 (6%) patients undergoing cold knife conization recurred, compared to 4 of 14 (29%) managed with LLETZ, despite a 63.4-month shorter mean follow-up interval for the LLETZ patients. Conclusions: Cold knife conization is associated with a lower rate of recurrence of cervical adenocarcinomain situcompared to LLETZ. We recommend cold knife conization for patients who are not treated with hysterectomy. 相似文献
180.
Metin Taskin M.D. Bel Barker M.D. Anthony Calanog M.D. Susan Jormark M.D. 《Gynecologic oncology》1996,62(3):400-404
A 58-year-old postmenopausal woman with primary ovarian serous carcinoma presented with the syndrome of inappropriate antidiuresis (SIAD). Preoperative workup showed serum sodium level of 110 mEq/liter and antidiuretic hormone level of 3.3 pg/ml. The serum and urine osmolarity were 239 and 371, respectively. Antidiuretic hormone was demonstrated in tumor cells by immunohistochemistry. To the best of the authors’ knowledge, this represents the first case of SIAD due to primary ovarian tumor. 相似文献