全文获取类型
收费全文 | 19550篇 |
免费 | 1265篇 |
国内免费 | 123篇 |
专业分类
耳鼻咽喉 | 207篇 |
儿科学 | 274篇 |
妇产科学 | 270篇 |
基础医学 | 2630篇 |
口腔科学 | 456篇 |
临床医学 | 1791篇 |
内科学 | 3899篇 |
皮肤病学 | 511篇 |
神经病学 | 2232篇 |
特种医学 | 1235篇 |
外科学 | 3665篇 |
综合类 | 112篇 |
一般理论 | 8篇 |
预防医学 | 666篇 |
眼科学 | 213篇 |
药学 | 1231篇 |
中国医学 | 13篇 |
肿瘤学 | 1525篇 |
出版年
2023年 | 172篇 |
2022年 | 273篇 |
2021年 | 506篇 |
2020年 | 344篇 |
2019年 | 457篇 |
2018年 | 523篇 |
2017年 | 433篇 |
2016年 | 523篇 |
2015年 | 651篇 |
2014年 | 789篇 |
2013年 | 890篇 |
2012年 | 1517篇 |
2011年 | 1616篇 |
2010年 | 979篇 |
2009年 | 913篇 |
2008年 | 1362篇 |
2007年 | 1376篇 |
2006年 | 1302篇 |
2005年 | 1220篇 |
2004年 | 1098篇 |
2003年 | 1010篇 |
2002年 | 944篇 |
2001年 | 214篇 |
2000年 | 170篇 |
1999年 | 218篇 |
1998年 | 166篇 |
1997年 | 178篇 |
1996年 | 97篇 |
1995年 | 101篇 |
1994年 | 80篇 |
1993年 | 56篇 |
1992年 | 87篇 |
1991年 | 71篇 |
1990年 | 62篇 |
1989年 | 67篇 |
1988年 | 62篇 |
1987年 | 38篇 |
1986年 | 43篇 |
1985年 | 38篇 |
1984年 | 35篇 |
1983年 | 22篇 |
1982年 | 31篇 |
1981年 | 12篇 |
1980年 | 16篇 |
1979年 | 23篇 |
1978年 | 20篇 |
1977年 | 15篇 |
1975年 | 18篇 |
1974年 | 14篇 |
1973年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Markus Friedrich Wolfram Sterry Khusru Asadullah 《Journal der Deutschen Dermatologischen Gesellschaft》2003,1(1):12-21
The current standard systemic therapeutic modalities for psoriasis have many potential side effects. Progress made in the understanding of the pathophysiology of psoriasis as a T‐cell‐mediated dermatosis provide options for new more precise therapeutic approaches. These immunological therapeutic strategies involve the inhibition/depletion of activated T‐lymphocytes, the inhibition of antigen presentation and thus the regulation of T‐cell activation, the inhibition of adhesion of inflammatory cells, the inhibition of effects of proinflammatory mediators and the administration of antiinflammatory cytokines. This article summarizes these new systemic therapeutic approaches. Clinical results in the early studies have been mixed. In the next years further results of phase II‐ and phase III‐studies may be expected, which should allow better assessment of the potential of those particular approaches. Some of these approaches could lead to the approval of new drugs to treat psoriasis and to enhance or replace already existing therapeutic options. Furthermore results of therapeutic experiments should contribute to a better understanding of the disease. As we learn which mechanisms are more or less important for the disease, we will be better able to plan intervention strategies. 相似文献
42.
H J Wenisch B H Markus G H Herrmann K H Usadel A Encke 《Zentralblatt für Chirurgie》1992,117(6):334-342
Islet cell carcinoma is rare. Even in advanced metastasizing tumors, relatively long survival times were reported. Aim of surgical treatment is complete removal of the tumor mass, if possible. When not, palliative procedures were described to be efficient in some of the cases. In the literature, among the first patients with regional metastasizing intraabdominal malignancies and upper abdominal exenteration, some cases with neuroendocrine tumors were reported. Aim of the following study is to describe the results in 4 patients with metastasizing islet cell carcinomas, which were treated by multi-visceral upper abdominal exenteration and combined orthotopic liver transplantation. 相似文献
43.
Misuse of zopiclone and convulsions during withdrawal. 总被引:3,自引:0,他引:3
It has been documented that benzodiazepines have the potential to cause dependence and withdrawal reactions, including convulsions. However, the available data concerning zopiclone, a nonbenzodiazepine hypnotic, are insufficient. The present study describes the case of a 36-year-old man who repeatedly misused zopiclone, in daily doses of 60-90 mg. Furthermore, the patient suffered from convulsion on two occasions following abrupt withdrawal of zopiclone. The concomitant use of alcohol, trimipramine, and promazine may have contributed to the development of convulsions. It is concluded that zopiclone may cause problems associated with misuse and withdrawal reactions similar to those of benzodiazepines. 相似文献
44.
Mauri J. Marttunen Hillevi M. Aro Markus M. Henriksson Jouko K. Lönnqvist 《European child & adolescent psychiatry》1994,3(2):101-110
Detailed characteristics of adolescent suicides (aged 13–19 years) with adjustment disorders (AD) (N=11) or no psychiatric diagnosis (N=3) in a nationwide adolescent suicide population (N=53) from Finland are presented. The data were collected in a psychological autopsy study of all suicides in Finland (N=1397) during a 12-month period in 1987–1988. Data collection included thorough interviews with the victims' family members and professionals, and information from official records. All the suicides with AD or no diagnosis were males. Most of these victims used highly lethal suicide methods. Previous psychiatric treatment and previous suicide attempts were rare. They were seldom under the influence of alcohol when committing suicide. The process leading to suicide seemed to be of relatively short duration. According to informant reports, withdrawn or narcissistic individual characteristics predominated in many cases. Psychosocial stressors preceding suicide often involved interpersonal losses or conflicts. Talking of suicidal intentions prior to the act was common, indicating the need to take seriously all adolescents' expressions of intended suicide, even in the absence of explicit psychopathology.
Zusammenfassung Es werden detaiilierte Beschreibungen von Selbst-morden im Jugendalter, verbunden mit Anpassungsstörungen (N=11) oder keiner psychiatrischen Diagnose (N=3) vorgestellt. Diese stammten aus der Gesamtheit aller jugendlichen Selbstmörder (N=53) aus Finnland. Die Daten wurden in einer psychologischen Obduktionsstudie aller Selbstmörder Finnlands (N=1397) während eines einjährigen Zeitraumes zwischen 1987 und 1988 gesammelt. Die Datenerhebung umfaßte ausgiebige Interviews mit den Familienmitgliedern, beteiligten Fachkräften und Informationen von offizieller Seite. Die Selbstmörder mit Anpassungstörungen oder keiner Diagnose waren alle männlich. Die meisten dieser Opfer benützten sehr letale Suizidmethoden. Vorangegangene psychiatrische Behandlungen und Selbstmordversuche waren selten. Sie standen nur selten unter dem Enfluß von Alkohol, als der Selbstmord vollzogen wurde. Der Prozeß, der zu dem Suizid führte, schien von relativ kurzer Dauer zu sein. Entsprechend den Angaben der Informanden prädominierten in vielen Fällen zurückgezogene oder narzißtische Persönlichkeitsmerkmale. Psychosoziale Stressoren, die dem Suizid vorangingen, umfaßten interpersonelle Verluste oder Konflikte. Häufig wurde über die Suizidabsichten vor der Tat gesprochen. Dies verdeutlicht die Notwendigkeit, alle Suizidäußerungen von Jugendlichen ernstzunehmen, selbst dann, wenn eine explizite Psychopathologie fehlt.
Résumé Les caractéristiques détaillées de suicides d'adolescents (âgés de 13 à 19 ans) avec troubles avec l'adaptation (AD) (N=11) ou l'absence de diagnostic psychiatrique (N=3) sur une population de suicides d'adolescents s'étendant sur l'ensemble du pays (N=53), la Finlande sont présentées. Les faits ont été collectés dans le cadre d'une étude d'autopsie psychologique de tous les suicides en Finlande (N=1397) pendant une période de 12 mois 1987–1988. Le recueil des faits incluait des interviews avec les membres de la famille des victimes et les professionels ainsi que les informations provenant de documents officiels. Tous les suicides avec un trouble de l'adaptation ou sans diagnostic étaient masculins. La plupart de ces victimes utilisait des méthodes hautement mortelles. Les traitements psychiatriques précédents et les tentatives précédentes de suicides étaient rares. Ils étaient rarement sous l'influence de l'alcool quand ils ont commis les suicides. Le processus conduisant au suicide semblait être de durée relativement brève. Selon les rapports d'information, une attitude de retrait ou des caractéristiques individuelles de retrait prédominaient dans la majorité des cas. Les facteurs de stress psycho-sociaux précédent le suicide impliquaient souvent des pertes inter-personnelles ou des conflits. Parler du désir du suicide devant le passage à l'acte était habituel indiquant la nécessité de prendre au sérieux tous les adolescents exprimant le désir de suicide, même en l'absence d'une psychopathologie explicite.相似文献
45.
On the basis of observations of the course taken by 5 patients with so-called Locked-in Syndrome (LIS), the level of functional performance that can be achieved by long-term rehabilitation notwithstanding very severe initial symptoms is set out. The priority measures in the early phases of the condition and the particular problems of long-term rehabilitation are summarized in a checklist. Technical aids to ameliorate communication are dealt with in some detail. Special importance is attributed to patient-centered psychotherapeutic support and to family involvement. 相似文献
46.
Anne F. Mannion Barbara R. Weber Jiri Dvorak Dieter Grob Markus Müntener 《Journal of orthopaedic research》1997,15(6):881-887
A knowledge of the alteration in the fibre type profile of paraspinal muscle associated with low back pain is essential for the design of successful rehabilitation programmes. In attempting to compare the muscles of patients with low back pain with those of controls, few previous studies have considered factors such as gender, age, and size of the subjects, each of which can potentially confound interpretation of the results. We obtained samples of lumbar paraspinal muscle during spinal surgery from 21 patients with low back pain and, using the percutaneous biopsy technique, from 21 control volunteers matched for gender, age, and body mass. The samples were subject to routine histochemicsl typcal analysis to determine characteristics of muscle fibre type. Compared with controls, the muscle of the patients had a significantly higher proportion of type-IIB (fast-twitch glycolytic) fibres than type- I (slow oxidatve) fibres. The mean size of a given fibre type did not differ between the patients and the controls. Consequently, the relative area of the muscle iccupied by type-IIB fibres was higher and that by type-I fibres Was lower in the patients. The patients had a greater number of muscle samples with more than 1% type-IIC fibres, and abnormalities that could be described as pathological were more marked in the patients than in the controls. In conclusion, the paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue. 相似文献
47.
Markus Dietlein Klemens Scheidhauer Eberhard Voth Peter Theissen Harald Schicha 《European journal of nuclear medicine and molecular imaging》1997,24(11):1342-1348
Metastases of differentiated thyroid cancer may show different uptake patterns for fluorine-18 fluorodeoxyglucose and [131I]NaI. FDG positron emission tomography (PET), iodine-131 whole-body scintigraphy (131I WBS) and magnetic resonance imaging were performed in 58 unselected patients, and spiral computed tomography (CT) of the
lung in 25 patients. Thirty-eight patients presented with papillary carcinomas, 15 patients with follicular carcinomas and
five patients with variants of follicular carcinoma. Primary tumour stage (pT) was pT1 in 3, pT2 in 19, pT3 in 11 and pT4
in 25 cases. For the detection of metastases, FDG PET was found to have a sensitivity of 50%, 131I WBS a sensitivity of 61%, and the two methods combined a sensitivity of 86%. When FDG PET was limited to patients with elevated
thyroglobulin (Tg) levels and negative 131I WBS, the sensitivity of this algorithm was 82%. Of the 21 patients with lymph node metastases, seven presented with FDG
uptake but no iodine uptake. In four of them, a second FDG hot spot appeared in a lymph node metastasis of normal size. Five
of the seven patients underwent surgery. None of the eight patients with pulmonary metastases smaller than 1 cm exhibited
FDG uptake, while five of them had iodine uptake. All had positive results on spiral CT. In conclusion, FDG PET cannot be
substituted for 131I WBS. If the Tg level is elevated and 131I WBS is negative, FDG PET can be used to detect lymph node metastases and complements anatomical imaging. A spiral CT of
the lung is useful to exclude pulmonary metastases before planning a dissection of iodine-negative lymph node metastases.
Received 2 May and in revised form 8 July 1997 相似文献
48.
Markus Kohler Hans M. Eppenberger Imogen Cordt-Riehle Christian Michel 《Acta oncologica (Stockholm, Sweden)》1992,31(6):673-677
Urination frequency and cystic pressure resistance have been used as end-points to assess x-ray-induced changes of bladder function. Whole or half bladders of adult male rabbits were irradiated, caudally or cranially. The absorbed dose was 33 Gy, 36 Gy or 39 Gy, given in 5 daily fractions. Animals which received a whole bladder dose of 39 Gy or 36 Gy showed increased urination frequency and enhanced bladder pressure resistance during the whole follow-up time of 100 weeks, compared with the sham-irradiated controls. At half bladder irradiation, only the highest doses (39 Gy to the cranial part of the bladder and 39 Gy or 36 Gy to the caudal part) gave rise to a slight increase in frequency at about 20 weeks after exposure. 相似文献
49.
Yuji Baba Markus M. Lerch David D. Stark Akihiro Tanimoto Burkhard P. Kreft Longhai Zhao Ashok K. Saluja Mutsumasa Takahashi 《Journal of magnetic resonance imaging : JMRI》1994,4(5):647-651
Previously unreported effects of tissue storage were recently observed in the authors' experimental magnetic resonance (MR) studies. To evaluate the effect of elapsed time after excision and storage temperature on tissue relaxation time measurements, tissue samples from the liver, pancreas, kidney, testis, spleen, and brain were obtained in rats. T1 and T2 were first measured within 5 minutes of excision, and between subsequent measurements, tubes were kept in a water bath at 40°C, at room temperature (28°C), or in an ice bath (4°C). Cellular and organellar integrity was assessed with electron microscopy and correlated with the MR findings. At 40°C (20-MHz spectrometer), the T1 of liver decreased from 280 msec ± 8 to 212 msec ± 10 during the first 60 minutes; the T1 of pancreas decreased from 276 msec ± 3 to 208 msec ± 2. Other tissues showed less than a 5% decrease in T1. T2 changes were smaller than T1 changes in all tissues. Electron microscopy of pancreatic acinar cells showed postmortem changes in mitochondria evolving over the first 60 minutes after death. Manganese loading experiments implicated mitochondrial manganese stores in the observed enhanced postmortem decrease in T1. This study calls into question reported relaxation time data for liver and pancreas. MR studies of excised tissues must account for time and temperature to prevent systematic experimental errors. 相似文献
50.
Markus Kohlhaas Olaf Stahlhut Joachim Tholuck Gisbert Richard 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1997,94(7):515-518
Ziel der vorliegenden Untersuchung war es, das Ausma? der Hornhautsch?digung durch eine Kataraktextraktion im Hinblick auf
das Hornhautendothel und die Hornhautdicke zu untersuchen.
Patienten und Methode: In einer prospektiven Untersuchung wurde die Entwicklung der Hornhautdicke und der Endothelzelldichte
an 48 Patienten untersucht. Die Patienten wurden mittels Phakoemulsifikation operiert. Die Hornhautdicke wurde dabei mit einem
Ultraschallpachymeter bei 12 Uhr und im Hornhautzentrum und die Endothelzelldichte mit einer Endothelzellkamera an den gleichen
Me?punkten pr?operativ sowie 4 Wochen, 4 Monate und 1 Jahr postoperativ bestimmt.
Ergebnisse: Ein Jahr postoperativ nahm die Hornhautdicke nach Phakoemulsifikation an der 12-Uhr-Position um ca. 9% und im
Hornhautzentrum um ca. 12% im Vergleich zum pr?operativen Wert zu. Die Endothelzelldichte war 1 Jahr postoperativ an der 12-Uhr-Position
um ca. 27% und im Zentrum um ca. 18% reduziert. Das Patientenalter korrelierte signifikant mit dem Zellverlust an beiden Me?punkten.
Bezüglich der Dickenzunahme ist keine signifikante Korrelation festzustellen.
Schlu?folgerung: Nach einer Kataraktextraktion ist der Hornhautstoffwechsel reduziert. Als Indikator k?nnen der Verlauf der
Endothelzelldichte und der Dicke herangezogen werden.
相似文献