全文获取类型
收费全文 | 16111篇 |
免费 | 1235篇 |
国内免费 | 431篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 98篇 |
妇产科学 | 3639篇 |
基础医学 | 2107篇 |
口腔科学 | 71篇 |
临床医学 | 1154篇 |
内科学 | 559篇 |
皮肤病学 | 63篇 |
神经病学 | 201篇 |
特种医学 | 250篇 |
外国民族医学 | 16篇 |
外科学 | 673篇 |
综合类 | 2763篇 |
现状与发展 | 2篇 |
预防医学 | 772篇 |
眼科学 | 14篇 |
药学 | 1269篇 |
7篇 | |
中国医学 | 783篇 |
肿瘤学 | 3322篇 |
出版年
2024年 | 40篇 |
2023年 | 221篇 |
2022年 | 464篇 |
2021年 | 712篇 |
2020年 | 522篇 |
2019年 | 500篇 |
2018年 | 502篇 |
2017年 | 646篇 |
2016年 | 655篇 |
2015年 | 656篇 |
2014年 | 1109篇 |
2013年 | 1241篇 |
2012年 | 907篇 |
2011年 | 998篇 |
2010年 | 756篇 |
2009年 | 764篇 |
2008年 | 843篇 |
2007年 | 805篇 |
2006年 | 793篇 |
2005年 | 697篇 |
2004年 | 560篇 |
2003年 | 535篇 |
2002年 | 434篇 |
2001年 | 376篇 |
2000年 | 332篇 |
1999年 | 240篇 |
1998年 | 179篇 |
1997年 | 167篇 |
1996年 | 187篇 |
1995年 | 158篇 |
1994年 | 128篇 |
1993年 | 98篇 |
1992年 | 93篇 |
1991年 | 70篇 |
1990年 | 56篇 |
1989年 | 51篇 |
1988年 | 37篇 |
1987年 | 38篇 |
1986年 | 25篇 |
1985年 | 22篇 |
1984年 | 40篇 |
1983年 | 26篇 |
1982年 | 18篇 |
1981年 | 14篇 |
1980年 | 12篇 |
1979年 | 14篇 |
1978年 | 7篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1973年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Eight patients who developed severe ovarian hyperstimulation syndrome (OHSS) were identified among 1302 patients undergoing in-vitro fertilization (IVF) over a 1 year period (prevalence of 0.6%); 63% had ultrasonically diagnosed polycystic ovaries (PCO) and 75% were undergoing their first attempt at IVF. Pretreatment with a superactive luteinizing hormone-releasing hormone (LHRH) analogue significantly increased the prevalence of severe OHSS (1.1% versus 0.2%, P less than 0.05) compared with ovarian stimulation with clomiphene citrate and human menopausal gonadotrophin (HMG). The mean serum oestradiol concentration on the day of human chorionic gonadotrophin (HCG) administration was 8200 +/- 2300 pmol/l. A mean of 19.6 +/- 6.8 follicles had been aspirated and 13.1 +/- 7.7 oocytes recovered at transvaginal ultrasound-directed oocyte recovery. All patients had an embryo transfer and luteal support in the form of HCG. The clinical pregnancy rate was 88%, multiple pregnancy rate 71% and implantation rate 63.5 +/- 41.3%. In a group of seven patients who were hospitalized for moderate OHSS during the same period, peak oestradiol levels were significantly lower than in those with severe OHSS (P less than 0.05). Of the group with moderate OHSS, 57% had PCO, the clinical pregnancy rate was 100% and multiple pregnancy rate 43%. Patients with ultrasound-diagnosed PCO have an increased risk of developing OHSS and the dose of HMG administered to them should be minimized. In patients at risk of developing OHSS, progesterone instead of HCG should be used for luteal support. Transfer of a maximum of two embryos or freezing all embryos for transfer in a subsequent cycle may reduce the likelihood of multiple pregnancy. 相似文献
12.
Karen G. Louie Thomas C. Hamilton Robert H. Shoemaker Robert C. Young Robert F. Ozols 《Investigational new drugs》1992,10(2):73-78
Summary Five compounds which were identified as potential new anticancer drugs inin vitro screening with the human tumor colony forming assay were selected for further evaluation usingin vitro andin vivo models of human ovarian cancer. Three of five compounds were found to inhibitin vitro colony formation of ovarian cancer cell lines derived from both untreated and combination chemotherapy refractory patients. One compound was also found to prolong survival in a human ovarian carcinoma xenograft model system. This compound, chloroquinoxaline sulfonamide, was selected for development and has shown preliminary indication of activity in phase I clinical testing. 相似文献
13.
Timo Laatikainen Henri Kurunmäki Aarne Koskimies 《Journal of assisted reproduction and genetics》1988,5(1):14-17
Of 70 cycles stimulated with clomiphene and human menopausal gonadotropin (hMG) for an in vitro fertilization-embryo transfer (IVF-ET) program, a short luteal phase of 11 days or less was found in 18. In this group the mean estradiol and progesterone levels were elevated in the early luteal phase. Despite the elevated initial values, progesterone levels fell rapidly at the mid luteal phase as a sign of premature luteolysis. The mean total amount of gonadotropin administered and the mean number of follicles punctured and of oocytes recovered did not show any significant difference between the groups of normal and short luteal phases. The present findings support the theory that hyperestrogenism in the early luteal phase may initiate the premature luteolysis observed in clomiphene-menopausal gonadotropin-stimulated cycles. 相似文献
14.
Gianaroli L.; Ferraretti A.P.; Feliciani E.; Tabanelli C.; Magli C.; Fortini D. 《Human reproduction (Oxford, England)》1994,9(2):220-225
In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation. 相似文献
15.
S Lipitz Z Ben-Rafael D Bider J Shalev S Mashiach 《Human reproduction (Oxford, England)》1991,6(10):1478-1479
A patient who suffered from polycystic ovarian disease and anovulation, was treated with pure follicle stimulating hormone for induction of ovulation. The treatment was stopped and human chorionic gonadotrophin was not administered because of high serum oestradiol levels and multiple follicular development. Ovulation occurred 11 days after pure follicle stimulating hormone was discontinued, the patient developed third-degree ovarian hyperstimulation syndrome and conceived with a quintuplet pregnancy. 相似文献
16.
17.
Morris R.S.; Paulson R.J.; Sauer M.V.; Lobo R.A. 《Human reproduction (Oxford, England)》1995,10(4):811-814
Ovarian hyperstimulation syndrome (OHSS) is a serious complicationof gonadotrophin usage but it is difficult to accurately predictits occurrence. Previous investigators have identified the combinationof high oestradiol concentrations and oocyte number as beingpredictive in 80% of cases. In this study we sought to identifythe incidence of severe OHSS in patients with high oestradiolconcentrations and large numbers of oocytes and to evaluatethe importance of pregnancy in the development of OHSS. Between1990 and 1993, we studied 139 cycles using two assisted reproductivetechniques [oocyte donor, n =72; in-vitro fertilization (IVF),n = 67] in which either oestradiol (>4000 pg/ml), oocytenumber (>25), or both were elevated. OHSS was diagnosed bystandard criteria. There were no cases of severe OHSS in theoocyte donor group and six in the IVF group. Among 10 patientswith oestradiol concentration >6000 pg/ml and >30 oocytes,only one had OHSS (10%). The relative risk of OHSS with pregnancywas 12 (confidence interval 2.1866.14). We conclude thatthe risk of OHSS even at high levels of stimulation is lowerthan previously believed. Secondly, donors have a very low riskof OHSS, probably because of the absence of pregnancy. As such,cryopreservation of all oocytes in IVF cycles is a reasonablealternative to cycle cancellation or use of adjunctive medication. 相似文献
18.
Ng Esther; Leader Arthur; Claman Paul; Domingo Minerva; Spence John E.H. 《Human reproduction (Oxford, England)》1995,10(4):807-810
A cohort study was undertaken to compare the effect at the timeof oocyte retrieval of the i.v. administration of either 1000ml of lactated Ringer' solution or 1000 ml of a 5% solutionof human albumin on in-vitro fertilization patients at riskfor severe ovarian hyperstimulation syndrome (OHSS). A totalof 207 patients with an oestradiol concentration > 10 000pmol/l and/or > 15 follicles (>10 mm diameter) on theday of human chorionic gonadotrophin (HCG) injection were reviewed.Of these, 158 women received 500 ml of lactated Ringerssolution both before and after egg retrieval, and 49 women receivedtwo infusions of 500 ml of 5% human albumin in normal salineat the time of egg retrieval. Severe OHSS developed in two patientswho received human albumin and in 10 women who did not receivethe albumin. This difference was not statistically significant.There were no differences between the two groups in terms ofage, number of follicles punctured at transvaginal oocyte retrievalor oestradiol concentration at the time of HCG injection. Theadministration of a 5% human albumin solution does not preventthe development of severe OHSS in at risk patients. It doesappear to blunt the severity of the condition. 相似文献
19.
Giovanni Scambia MD Elvira Foti MD Gabriella Ferrrandina MD Francesco P. Leone MD Angiolo Gadducci MD Pierluigi Benedetti-Panici MD Salvatore Mancuso MD 《American journal of obstetrics and gynecology》1996,175(6):1606-1610
OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ2 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.) 相似文献
20.
Arlene S. King William J. Threlfall Pierre R. Band Richard P. Gallagher 《American journal of industrial medicine》1994,26(1):125-132
The mortality profile of female nurses and teachers in British Columbia (BC) was examined using age-standardized proportional mortality ratios (PMRs) calculated for the period 1950–1984. Lowered overall mortality among nurses was seen for degenerative heart disease and for cerebrovascular accidents. Significantly elevated PMR values were observed for cancer of the breast and ovary in nurses of age 20–65 years. PMRs were significantly elevated for cancer of the pancreas and leukemia among those age 20 years and older. Elevated values were also observed for motor vehicle accidents and suicide among nurses in both age groups. Lower than expected mortality from degenerative heart disease and cerebrovascular accidents was seen in working age teachers (age 20–65 years). However, elevated PMRs were detected for carcinoma of the colon, breast, endometrium, brain, and melanoma. Among those 20 years and over, significantly elevated PMRs were also observed for cancers of the ovary and other digestive organs. Elevated PMRs were found for motor vehicle and aircraft accidents. Mortality from cirrhosis of the liver was lower than anticipated in both teachers and nurses. A number of significant PMRs declined when deaths of “homemakers” were withdrawn from the comparison group used to generate PMR values, suggesting that risk of death from various causes among women working outside the home differ from those seen in women who are predominantly in the home. 相似文献