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排序方式: 共有4694条查询结果,搜索用时 12 毫秒
1.
Devagi Kanakaraju Nurfatyha Rusydah bt Mohamad Shahdad Ying-Chin Lim Andrea Pace 《Sustainable Chemistry and Pharmacy》2019
The use of multifunctional materials for water remediation is a modern approach where adsorption phenomena and heterogeneous photocatalysis can be applied for the removal of pollutants. Since the ideal remediation system should be able to remove both organic and inorganic pollutants, a crucial aspect to consider is the knowledge of operational parameters affecting the removal process, especially when heavy metal ions are present in concoction as in real systems. Given the proven efficiency of multifunctional TiO2/Alg/FeNPs magnetic beads for the removal of model organic pollutants, this study investigated the possibility to exploit such system also for the removal of mixed heavy metals (MHM), specifically Cr(III), Cu(II), and Pb(II) ions, under ultraviolet irradiation at a wavelength of 254 nm. After a preliminary screening on the optimal catalyst loading, operating parameters such as the initial concentration of metal ions, contact and irradiation time, and pH were investigated to optimize the removal of metal ions using response surface methodology (RSM) via Box–Behnken design. Starting from a MHM solution containing 44 ppm of each metal ion, the removal of Pb(II), Cr(III), and Cu(II) ions in the aqueous solution was nearly completed (>98.4%) for all three ions within 72 min of irradiation at almost neutral pH (pH = 6.8). The stability of TiO2/Alg/FeNPs was confirmed by retrieving and reusing the beads in three consecutive cycles of heavy metals removal without observing significant changes in catalyst efficiency. 相似文献
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3.
Hisham Abdel Ghani Ahmed El-Naggar Mohamad Hegazy Atef Hanna Yehia Tarraf Samia Temtamy 《Journal of children's orthopaedics》2007,1(5):313-322
Purpose Congenital clasped thumb is a deformity that is associated with heterogeneous congenital anomalies and it has been addressed
in many congenital syndromes. The aim of this study was to diagnose and evaluate cases of clasped thumb as regards the associated
congenital anomalies and syndromes, and evaluation of the results of treatment of such cases.
Methods A prospective study on 40 patients with 73 clasped thumbs was done. All the patients’ data regarding their personal, family,
pregnancy and developmental histories were recorded. All the patients were exposed to thorough clinical and radiological examination
and genetic assessment. The cases were classified using the Tsuyuguchi et al. (J Hand Surg [Am] 10:613–618, 1985) classification into three types. Conservative treatment was adopted in ten hands, and surgical treatment was performed for
28 hands in 17 patients, with an average follow-up of 26 months.
Results Positive consanguinity was recorded in 57.5% of cases. Associated anomalies were recorded in 77.5% of cases. Type I was the
most common one, followed by type III and then type II. Conservative treatment is effective in type I cases when presented
early, and all patients were satisfied with the results of surgical treatment.
Conclusions We reported associated anomalies which are to our knowledge have not mentioned before in the literature which include; congenital
blindness, radial deviation of the index finger and ventricular septal defect. We found that 68% of the patients had associated
syndromes, and this has not been mentioned before. In this study, we found that there were no difference between type II and
type III clasped thumb as regards the pathological findings, severity, the operative procedures, the treatment protocol and
the operative results. Properly planned treatment gives satisfactory results. 相似文献
4.
The clinical, biochemical and pathological features of 31 patients with thyroid carcinoma managed at Hospital Universiti Sains Málaysia, Kubang Kerian from 1985 to 1989 were analyzed. There were 25 females and 6 males. The types of carcinoma were: papillary-17 cases; follicular-10 cases; medullary-2 cases and anaplastic-2 cases. For papillary carcinoma the mean age of the patients was 52.9 years. For follicular carcinoma the mean age was 48.3 years, for medullary carcinoma, 48.5 years and for anaplastic, 74.5 years. All patients had pre-existing goitre except for 2 and most presented with advanced disease. The mean duration of symptoms for papillary carcinoma was 3.7 years, follicular carcinoma 1.6 years, medullary carcinoma 13.5 years and anaplastic carcinoma 6 months. 12 patients presented with goitre of increasing size; 9 had compression symptoms; 4 presented with cervical lymph node enlargement and 6 presented with bony pains of whom 2 had paraplegia. None of the patients were ever thyrotoxic or hypothyroid. Treatment in general was unsatisfactory because of patients' non-acceptance of surgery and/or radioactive iodine. 相似文献
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6.
Mohamed Eid Fawzy Mohamed Shoukri Walid Hassan Vijayaraghavan Nambiar Miltiadis Stefadouros Charles C Canver 《Catheterization and cardiovascular interventions》2007,69(1):40-46
BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献
7.
Suhair S Eid 《Clinical laboratory science》2002,15(4):196-199
Hereditary thrombophilia is caused by various inherited disorders. Most lead to a familial tendency to recurrent venous, not arterial, thrombosis, usually at a young age, and with spontaneous onset. Most of the genetic defects known today affect the function of natural anticoagulant pathways, in particular, the protein C system. In this study, 602 (265 female, 337 male) patients with suspected thrombosis, arterial or venous, were referred to King Hussein Medical Center in Amman, Jordan. The prevalence of hereditary deficiencies of antithrombin (AT), protein S (PS), and protein C (PC) were studied over a seven-year period (1993-2000). Activated protein C (APC-R) resistance subjects were studied over four years (1996-2000). The mean age was 30 years in females and 42 years in males. A diagnosis was established in 22.4% (n = 135) of the subjects (20.3% venous, 2.1% arterial). Protein C deficiency was found in 3.8%, protein S deficiency in 2.3% and antithrombin deficiency in 1.4% of our sample group. An APC-R problem was seen in 23.0% (n = 89) of the surveyed population. Out of the APC-R patients, 75.0% had the DNA analysis of a factor V Leiden mutation present. Of the subjects found to have the mutation 87.0% were heterozygous and 13.0% were homozygous. These results confirm that APC-R, as a result of factor V Leiden mutation, is the most prevalent cause of thrombosis, and thrombophilia is related to venous, not arterial, thrombosis. 相似文献
8.
R Steimlé G Jacquet J Godard C Billerey R el Mohamad 《Chirurgie; mémoires de l'Académie de chirurgie》1992,118(8):464-8; discussion 469
One case of a cervical osteoid osteoma is presented and compared with infrequent similar cases from the literature. The authors recall the diagnosis difficulties, facing a long standing not explained neck pain due to poor neurological and current radiological informations. The interest of the bone scintigraphy, CT scan and M.R.I. are emphasized. Like in other cases, the pain disappeared after surgical removal of the tumor. The eventually associated scoliosis often rectify too. 相似文献
9.
Newly hatched White Leghorn male chicks were used in this study. Different doses of T3 (O.1 or 1 ppm) or TRH (1 or 5 ppm) were administered in the feed for an 8-week period. Chicken growth hormone (cGH) (10 μg/kg BW) was injected (i.v.) into a different group of chicks twice daily for 1 week starting at 7 weeks of age. A different group received both T3 (0.1 and 1 ppm) and cGH. Serum concentrations of T4, T3 and GH, antibody production against sheep red blood cells (SRBC) and Brucella Abortus (BA), and in vitro proliferative response of both T- and B-lymphocytes to mitogenic stimulation were measured. Supplementation of T3 (1 ppm) significantly lowered T4 and increased T3 concentrations. No effect of any hormone treatment on antibody production was observed. T3 supplementation and cGH injection alone or with T3 (0.1 ppm) significantly increased blastogenic response of lymphocytes to either Con-A or LPS mitogenic stimulation. It was concluded that T3 and GH are involved in lymphocyte activity of chickens. 相似文献
10.
OBJECTIVE: To evaluate beta-endorphin secretion in euprolactinemic cases of luteal phase defect (LPD). DESIGN: Serial blood samples from the 18th to the 26th day of the menstrual cycle were assayed for beta-endorphin, progesterone (P), estradiol (E2), and prolactin (PRL) in cases of LPD and controls. Diagnosis of LPD was based on determinations of serum P and premenstrual endometrial biopsy. SETTING: From Cairo University Hospitals. PATIENT, PARTICIPANTS: Twenty-six women with LPD and 8 normal fertile women (controls) were chosen. INTERVENTIONS: None. MAIN OUTCOME MEASURES: beta-Endorphin, P, E2, and PRL concentrations were determined by the corresponding 125I radioimmunoassay. RESULTS: Plasma beta-endorphin level in cases of LPD varied from 2.58 to 9.14 pmol/L, whereas the level of controls varied from 2.41 to 5.57 pmol/L. The mean value of plasma beta-endorphin in cases of LPD was significantly higher than that of controls by 146% (P less than 0.0005). In spite of the significant decrease of serum P in cases of LPD, serum E2 level did not differ significantly from that of controls. CONCLUSION: The possible sources of beta-endorphin rise and its implication in the etiology of LPD are explained. 相似文献